<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE article  PUBLIC "-//NLM//DTD Journal Publishing DTD v3.0 20080202//EN" "http://dtd.nlm.nih.gov/publishing/3.0/journalpublishing3.dtd"><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" dtd-version="3.0" xml:lang="en" article-type="research article"><front><journal-meta><journal-id journal-id-type="publisher-id">IJAA</journal-id><journal-title-group><journal-title>International Journal of Astronomy and Astrophysics</journal-title></journal-title-group><issn pub-type="epub">2161-4717</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/ijaa.2012.21002</article-id><article-id pub-id-type="publisher-id">IJAA-18173</article-id><article-categories><subj-group subj-group-type="heading"><subject>Articles</subject></subj-group><subj-group subj-group-type="Discipline-v2"><subject>Physics&amp;Mathematics</subject></subj-group></article-categories><title-group><article-title>
 
 
  Revised Newtonian Formula of Gravity and Equation of Cosmology in Flat Space-Time Transformed from Schwarzschild Solution
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Xiaochun</surname><given-names>Mei</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>Ping</surname><given-names>Yu</given-names></name><xref ref-type="aff" rid="aff1"><sup>1</sup></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib></contrib-group><aff id="aff1"><addr-line>Institute of Innovative Physics in Fuzhou, Department of Physics, Fuzhou University, Fuzhou, China</addr-line></aff><author-notes><corresp id="cor1">* E-mail:<email>ycwlyjs@yeah.net(XM)</email>;<email>yupingpingyu@yahoo.com(PY)</email>;</corresp></author-notes><pub-date pub-type="epub"><day>28</day><month>03</month><year>2012</year></pub-date><volume>02</volume><issue>01</issue><fpage>6</fpage><lpage>18</lpage><history><date date-type="received"><day>January</day>	<month>3,</month>	<year>2012</year></date><date date-type="rev-recd"><day>February</day>	<month>7,</month>	<year>2012</year>	</date><date date-type="accepted"><day>February</day>	<month>16,</month>	<year>2012</year></date></history><permissions><copyright-statement>&#169; Copyright  2014 by authors and Scientific Research Publishing Inc. </copyright-statement><copyright-year>2014</copyright-year><license><license-p>This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/</license-p></license></permissions><abstract><p>
 
 
  By transforming the geodesic equation of the Schwarzschild solution of the Einstein’s equation of gravity field to flat space-time for description, the revised Newtonian formula of gravity is obtained. The formula can also describe the motion of object with mass in gravity field such as the perihelion precession of the Mercury. The space-time singularity in the Einstein’s theory of gravity becomes the original point r = 0 in the Newtonian formula of gravity. The singularity problem of gravity in curved space-time is eliminated thoroughly. When the formula is used to describe the expansive universe, the revised Friedmann equation of cosmology is obtained. Based on it, the high red-shift of Ia supernova can be explained well. We do not need the hypotheses of the universe accelerating expansion and dark energy again. It is also unnecessary for us to assume that non-baryon dark material is 5 - 6 times more than normal baryon material in the universe if they really exist. The problem of the universal age can also be solved well. The theory of gravity returns to the traditional form of dynamic description and becomes normal one. The revised equation can be taken as the foundation of more rational cosmology.
 
</p></abstract><kwd-group><kwd>General Relativity; Schwarzschild Metric; Cosmology; Friedmann Equation; Newtonian Gravity;Supernova; Hubble Constant; Dark Material; Dark Energy; Universe Accelerating Expansion;Universe Age</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>1. Introduction</title><p>Established on the foundation of curved space-time, Einstein’s theory of gravity is the dominate theory at present. However, Einstein’s theory has some difficulties hard to be overcome such as the problems of normalization, singu- larity and uniqueness of gravity field’s energy and so on. In addition, it is difficulty to solve the non-linear Einstein’s equation of gravity field. It is always attractive to reestablish the theory of gravity in flat space-time without these troubles. Since the 1940’s, many people has tried and many theories had been proposed [1,2]. These theories are consistent with Einstein’s one under the condition of weak fields, but are different in strong fields. Meanwhile, these theories also have some problems hard to be overcome.</p><p>The standard theory of cosmology faces many principle difficulties at present. As is proved below, the problems originate from the Friedmann equation which is unsuitable to describe the high speed expansion of the universe. The reason is that two simplified and improper conditions were used in the deduction of the Friedmann equation. They are the R-W metric and static energy momentum tensor. At present, the R-W metric is considered with</p><p>constant spatial curvature. However, the author had proved that strictly based on the curvature formula of the Riemannian geometry, when the scalar factor R(t) changes with time, the R-W metric has no constant curvature [<xref ref-type="bibr" rid="scirp.18173-ref3">3</xref>]. The common understanding about the spatial curvature of the R-W metric is wrong. This idea would impose great influence on cosmology. Due to this result, many conclusions in the cosmology such as the densities of dark material and dark energy should be re-estimated.</p><p>It is proved further in this paper that the R-W metric leads to the Galileo’s transformation of light’s velocity, instead of the Einstein’s transformation. So the R-W metric is not relativity metric and unsuitable to be taken as the basic space-time framework of modern cosmology.</p><p>Meanwhile, because relative velocities exist between materials and observers in the expansive universe, the equation of cosmology should use dynamic energy momentum tensor, rather than static one as commonly used in the current cosmology.</p><p>In fact, E. A. Milne pointed out in 1943 that the Friedmann equation of cosmology could be deduced based on the Newtonian formula of gravity [<xref ref-type="bibr" rid="scirp.18173-ref4">4</xref>]. It means that the Friedmann equation is equivalent to the Newtonian theory actually. It is only suitable for describing the process of low speed expansion of the universe, but not for the process of high speed expansion.</p><p>However, it is proved in this paper that if dynamic energy momentum tensor is used, the equation of cosmology would become very complex, so that it can not be solved actually. The pioneer of cosmology must have considered this problem and had to use static energy momentum tensor. In the early stage of cosmology, the Friedmann equation seemed to be appreciable because the expansive speed observed was low. When cosmology develops to present level, we observe the high speed expansion. In this case, the Friedmann equation becomes unsuitable for the problems such as the high red-shift of supernova. We have to find more precise method to describe them.</p><p>It is proved in this paper that by transforming the geodesic equation of the Schwarzschild solution of the Einstein’s equation of gravity field to flat space-time, the re- vised Newtonian formula of gravity can be obtained. The formula can well describe the perihelion precession of the Mercury. The space-time singularities in the Einstein’s theory of gravity become the point r = 0 in the revised New- tonian formula of gravity. We have no the trouble of singularities again.</p><p>When the revised formula is used to describe the expansive universe, we obtain the revised Friedmann equation. Based on it, the high red-shift of supernova can be explained well without the hypotheses of the universal accelerating expansion and dark energy. Many problems in- cluding the universe age to be too small can also be resolved well. In this way, we can get rid of the current puzzle situation of cosmology completely.</p></sec><sec id="s2"><title>2. Revised Newtonian Formula of Gravity Based on the Schwarzschild</title><sec id="s2_1"><title>2.1. Revised Newtonian Formula of Gravity</title><p>According to general relativity, the Schwarzschild metric (external solution) is</p><disp-formula id="scirp.18173-formula1148"><label>(1)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x1.png"  xlink:type="simple"/></disp-formula><p>Here<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x2.png" xlink:type="simple"/></inline-formula>. Let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x3.png" xlink:type="simple"/></inline-formula> and substitute (1) into the equation of geodetic line, we have the integrals</p><disp-formula id="scirp.18173-formula1149"><label>(2)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x4.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x5.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x6.png" xlink:type="simple"/></inline-formula> are constants. By cancelling <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x7.png" xlink:type="simple"/></inline-formula> from the formulas, we can obtain</p><disp-formula id="scirp.18173-formula1150"><label>(3)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x8.png"  xlink:type="simple"/></disp-formula><p>We define</p><disp-formula id="scirp.18173-formula1151"><label>(4)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x9.png"  xlink:type="simple"/></disp-formula><p>In which <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x10.png" xlink:type="simple"/></inline-formula> is eigen time, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x11.png" xlink:type="simple"/></inline-formula>is coordinate time. Then, let<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x12.png" xlink:type="simple"/></inline-formula>, we have from (2)</p><disp-formula id="scirp.18173-formula1152"><label>(5)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x13.png"  xlink:type="simple"/></disp-formula><p>Then, (3) becomes</p><disp-formula id="scirp.18173-formula1153"><label>(6)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x14.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x15.png" xlink:type="simple"/></inline-formula> is the angular momentum of unit mass. (6) is just the conservation formula of angel momentum.</p><p>We only discuss the motion of particles with mass in gravitational field. By considering (6), we write (1) as</p><disp-formula id="scirp.18173-formula1154"><label>(7)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x16.png"  xlink:type="simple"/></disp-formula><p>By considering (4) and (6), the formula above can be written as</p><disp-formula id="scirp.18173-formula1155"><label>(8)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x17.png"  xlink:type="simple"/></disp-formula><p>Taking the differential of (8) about<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x18.png" xlink:type="simple"/></inline-formula>, we get</p><disp-formula id="scirp.18173-formula1156"><label>(9)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x19.png"  xlink:type="simple"/></disp-formula><p>Note that all quantities in (9) are defined in curved space-time. According to the theory of the non-Euclidean geometry, although we can not transform whole metric of curved space-time into that of flat space-time in general, we can always transform the geodetic line described in curved space-time into that in flat space. Let<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x20.png" xlink:type="simple"/></inline-formula>, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x21.png" xlink:type="simple"/></inline-formula>and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x22.png" xlink:type="simple"/></inline-formula> represent the space-time coordinates of flat space-time, due to the invariability of<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x23.png" xlink:type="simple"/></inline-formula>, we have</p><disp-formula id="scirp.18173-formula1157"><label>(10)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x24.png"  xlink:type="simple"/></disp-formula><p>We see that the forms of third items on the two sides of the second equal sign of the formula above are completely the same. So we can take<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x25.png" xlink:type="simple"/></inline-formula>, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x26.png" xlink:type="simple"/></inline-formula>and get the relation between times <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x27.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x28.png" xlink:type="simple"/></inline-formula></p><disp-formula id="scirp.18173-formula1158"><label>(11)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x29.png"  xlink:type="simple"/></disp-formula><p>by considering (4), we get and from (8)</p><disp-formula id="scirp.18173-formula1159"><label>(12)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x30.png"  xlink:type="simple"/></disp-formula><p>Substituting it into (11), we get</p><disp-formula id="scirp.18173-formula1160"><label>(13)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x31.png"  xlink:type="simple"/></disp-formula><p>Comparing with (4), we have</p><disp-formula id="scirp.18173-formula1161"><label>(14)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x32.png"  xlink:type="simple"/></disp-formula><p>Because we have taken<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x33.png" xlink:type="simple"/></inline-formula>, all quantities on the right side of (14) have been defined in flat space-time. Note that in the classical Newtonian theory of gravity, at the directions of <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x34.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x35.png" xlink:type="simple"/></inline-formula> in plane polar coordinates system, the partial motion equations of unit mass are individually</p><disp-formula id="scirp.18173-formula1162"><label>(15)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x36.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1163"><label>(16)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x37.png"  xlink:type="simple"/></disp-formula><p>Substitute (16) into (15), we get</p><disp-formula id="scirp.18173-formula1164"><label>(17)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x38.png"  xlink:type="simple"/></disp-formula><p>Comparing with (9) and let<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x39.png" xlink:type="simple"/></inline-formula>, except the revised item in the bracket of (9), we see that the forms of (9) and (17) are completely similar. So we can write (9) as the following vector equation</p><disp-formula id="scirp.18173-formula1165"><label>(18)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x40.png"  xlink:type="simple"/></disp-formula><p>Let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x41.png" xlink:type="simple"/></inline-formula> and consider (6), the formula above can be transformed to</p><disp-formula id="scirp.18173-formula1166"><label>(19)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x42.png"  xlink:type="simple"/></disp-formula><p>This formula is the one used to describe the perihelion precession of the Mercury in general relativity. In the deduction process above, we use the equation of geodetic line (2). It means that we transform the equation of geodetic line into the revised formula of the Newtonian gravity, in stead of transforming whole curved space-time to flat space-time. But it is enough for us to describe an object’s motion in gravity field.</p><p>Now let’s prove that the effect of special relativity has been taken into account in (18). From (8), (12) and (14), we can obtain</p><disp-formula id="scirp.18173-formula1167"><label>(20)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x43.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1168"><label>(21)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x44.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1169"><label>(22)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x45.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1170"><label>(23)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x46.png"  xlink:type="simple"/></disp-formula><p>Comparing with (14), we get</p><disp-formula id="scirp.18173-formula1171"><label>(24)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x47.png"  xlink:type="simple"/></disp-formula><p>This is just the formula of time delay in special relativity. The result verifies the rationality of (18). Let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x48.png" xlink:type="simple"/></inline-formula> at last, we write (18) as</p><disp-formula id="scirp.18173-formula1172"><label>(25)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x49.png"  xlink:type="simple"/></disp-formula><p>It is the revised Newtonian formula of gravity based on general relativity. In the formula, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x50.png" xlink:type="simple"/></inline-formula>is the static mass of moving particle and the center static mass <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x51.png" xlink:type="simple"/></inline-formula> has spherical symmetry. Angle momentum makes gravity larger but speed makes it smaller. The result is equivalent to replace particle’s static mass with following effective mass in the Newtonian theory</p><disp-formula id="scirp.18173-formula1173"><label>(26)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x52.png"  xlink:type="simple"/></disp-formula><p>We can call m as the motion mass of gravity which is related to object’s speed and angle momentum.</p></sec><sec id="s2_2"><title>2.2. The Motion of Particle in Gravitational Field with Spherical Symmetry</title><p>For simplicity, we only discuss the motion of a particle moves along the radius vector direction with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x53.png" xlink:type="simple"/></inline-formula>. In this case, by considering (23), (25) becomes</p><disp-formula id="scirp.18173-formula1174"><label>(27)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x54.png"  xlink:type="simple"/></disp-formula><p>by multiplying <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x55.png" xlink:type="simple"/></inline-formula> on both sides of (27), the potential energy of the particle in gravitational field is</p><disp-formula id="scirp.18173-formula1175"><label>(28)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x56.png"  xlink:type="simple"/></disp-formula><p>The dynamic energy of particle is</p><disp-formula id="scirp.18173-formula1176"><label>(29)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x57.png"  xlink:type="simple"/></disp-formula><p>when<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x58.png" xlink:type="simple"/></inline-formula>, we have <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x59.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x60.png" xlink:type="simple"/></inline-formula>. So the law of energy conservation of a particle in the gravitational field can be written as</p><disp-formula id="scirp.18173-formula1177"><label>(30)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x61.png"  xlink:type="simple"/></disp-formula><p>when <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x62.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x63.png" xlink:type="simple"/></inline-formula>, we get the classic law of energy conservation in the Newtonian theory of gravity</p><disp-formula id="scirp.18173-formula1178"><label>(31)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x64.png"  xlink:type="simple"/></disp-formula><p>In the situation of<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x65.png" xlink:type="simple"/></inline-formula>, we calculate the problem in the weak field with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x66.png" xlink:type="simple"/></inline-formula>. By keeping items with the orders up to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x67.png" xlink:type="simple"/></inline-formula>, we have</p><disp-formula id="scirp.18173-formula1179"><label>(32)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x68.png"  xlink:type="simple"/></disp-formula><p>So the law of energy conservation is</p><disp-formula id="scirp.18173-formula1180"><label>(33)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x69.png"  xlink:type="simple"/></disp-formula><p>Here E is a constant.</p><p>Now let’s discuss the motion of a particle in the gravity field. Suppose that a particle falls freely along the radium direction of gravity field, its velocity and acceleration are individually</p><disp-formula id="scirp.18173-formula1181"><label>(34)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x70.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1182"><label>(35)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x71.png"  xlink:type="simple"/></disp-formula><p>when<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x72.png" xlink:type="simple"/></inline-formula>, we have <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x73.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x74.png" xlink:type="simple"/></inline-formula>. Suppose that the particle is at point <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x75.png" xlink:type="simple"/></inline-formula> when<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x76.png" xlink:type="simple"/></inline-formula>, by the integral of (34), we get</p><disp-formula id="scirp.18173-formula1183"><label>(36)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x77.png"  xlink:type="simple"/></disp-formula><p>It is obvious that every thing is normal within the region<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x78.png" xlink:type="simple"/></inline-formula>. The particle is monotonously accelerated by gravitation. There is no any singularity in the whole space- time. When particle is at the original point<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x79.png" xlink:type="simple"/></inline-formula>, we have</p><disp-formula id="scirp.18173-formula1184"><label>(37)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x80.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1185"><label>(38)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x81.png"  xlink:type="simple"/></disp-formula><p>It indicates that the speed of particle tends to have light’s speed in vacuum at point<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x82.png" xlink:type="simple"/></inline-formula>. Acceleration is also finite. So within the region<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x83.png" xlink:type="simple"/></inline-formula>, the motion of particle with static mass is continuous. Only at point<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x84.png" xlink:type="simple"/></inline-formula>, the force acted on particles becomes infinite. But this kind of singularity appears in any theories in which particles are considered with infinite small size, and have nothing to do with space-time singularity. The singularity of the Schwarzschild solution is eliminated.</p></sec></sec><sec id="s3"><title>3. The Fiedmann Equation of Cosmology Needs Relativity Revision</title><sec id="s3_1"><title>3.1. The Fiedmann Equation is Equivalent to the Newtonian Theory of Gravity</title><p>The Fiedmann equation of cosmology is based on the Einstein’s equation of gravity. Because the equation is too complex to solve, two simplified conditions are used. One is the R-W metric and another is the static energy momentum tensor. Using them, we obtain from the Einstein’s equation of gravity</p><disp-formula id="scirp.18173-formula1186"><label>(39)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x85.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x86.png" xlink:type="simple"/></inline-formula> is scalar factor, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x87.png" xlink:type="simple"/></inline-formula>is curvature constant factor, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x88.png" xlink:type="simple"/></inline-formula>is the universe material density and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x89.png" xlink:type="simple"/></inline-formula> is the intensity of pressure. By eliminating <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x90.png" xlink:type="simple"/></inline-formula> form (39), we obtain the Fiedmann equation</p><disp-formula id="scirp.18173-formula1187"><label>(40)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x91.png"  xlink:type="simple"/></disp-formula><p>Cosmic constant has not been considered in (39) and (40). We often either take it as zero, or combine it with effective material density for convenience.</p><p>However, British physicist E. A. Milne proved in 1943 that the Fiedmann equation could be deduced simply based on the Newtonian theory of gravity. Though the Fiedmann equation is described in curved space-time and the Newtonian theory of gravity is described in flat space-time, the results are the same actually when we use them to calculate practical problems, especially when we take curvature constant<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x92.png" xlink:type="simple"/></inline-formula>. However, the Newtonian theory of gravity is only suitable for the motions with low speeds. For the high speed expansion of the universe, it is unsuitable. The Fiedmann equation needs relativity revision due to this fact.</p><p>We now repeat Milne’s deduction below. According to the principle of cosmology, the universe can be considered as a huge sphere with uniform and isotropic material distribution. According to the Newtonian theory, gravity acted on a body located at point r inside the sphere is only related to the mass contained in the sphere with radius r, having nothing to do with the mass outside the sphere. Suppose that the mass of uniform sphere to be<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x93.png" xlink:type="simple"/></inline-formula>, in the direction of sphere radius, the Newtonian equation of gravity is</p><disp-formula id="scirp.18173-formula1188"><label>(41)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x94.png"  xlink:type="simple"/></disp-formula><p>For the expansive sphere, by considering co-moving coordinate <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x95.png" xlink:type="simple"/></inline-formula> in which <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x96.png" xlink:type="simple"/></inline-formula> has nothing to do with time, (41) becomes</p><disp-formula id="scirp.18173-formula1189"><label>(42)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x97.png"  xlink:type="simple"/></disp-formula><p>(42) is the same as the first formula of (39) when<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x98.png" xlink:type="simple"/></inline-formula>. Because mass is invariable in the expansive pro- cess, we have<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x99.png" xlink:type="simple"/></inline-formula>, here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x100.png" xlink:type="simple"/></inline-formula> is the time at present. We have</p><disp-formula id="scirp.18173-formula1190"><label>(43)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x101.png"  xlink:type="simple"/></disp-formula><p>Substituting (43) in (42) and taking the integral, we obtain (40). In this case, integral constant <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x102.png" xlink:type="simple"/></inline-formula> is equivalent with curvature constant in the R-W metric.</p><p>It is obvious that (40) is the direct result of the Newtonian theory of gravity, for it dose not contain any revised item of relativity. This is why the standard theory of cosmology is effective for same problems, but is ineffective for other problems such as the high red shift of supernova. The reason is that two simplified conditions are used, so that the Freidmann equation becomes non-relativity theory actually. We discuss these problems below.</p></sec><sec id="s3_2"><title>3.2. The R-W Metric Violates the Principle of Invariance of Light’s Velocity</title><p>According to the principle of cosmology, the universe is uniform and isotropy. The R-W metric is considered with the biggest space-time symmetry. Its form is</p><disp-formula id="scirp.18173-formula1191"><label>(44)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x103.png"  xlink:type="simple"/></disp-formula><p>In which <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x104.png" xlink:type="simple"/></inline-formula>is curvature factor. When<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x105.png" xlink:type="simple"/></inline-formula>, the me- tric becomes flat with</p><disp-formula id="scirp.18173-formula1192"><label>(45)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x106.png"  xlink:type="simple"/></disp-formula><p>For light’s motion, we have<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x107.png" xlink:type="simple"/></inline-formula>. When light moves along radius direction, we have<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x108.png" xlink:type="simple"/></inline-formula>. According to (45), we obtain</p><disp-formula id="scirp.18173-formula1193"><label>(46)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x109.png"  xlink:type="simple"/></disp-formula><p>For the light’s source fixed at point<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x110.png" xlink:type="simple"/></inline-formula>, coordinate <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x111.png" xlink:type="simple"/></inline-formula> does not change with time. But for the light emitted by light’s source, coordinate <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x112.png" xlink:type="simple"/></inline-formula> changes with time as described in (46). The velocity of space expansion is</p><disp-formula id="scirp.18173-formula1194"><label>(47)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x113.png"  xlink:type="simple"/></disp-formula><p>By considering (46) and (47), the velocity of light relative to observer located at the original point of reference frame is</p><disp-formula id="scirp.18173-formula1195"><label>(48)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x114.png"  xlink:type="simple"/></disp-formula><p>The formula indicates that light’s velocity is related to the expansion speed of space and violates the principle of invariance of light’s speed.</p><p>In fact, at the moment when light is just emitted out, (48) is the Galileo’s addition rule of light’s velocity. When light moves towards observer, minus sign is taken in (48) so light’s speed is less than its speed in vacuum. When the light moves apart from observer, plus sign is taken. In this case, light’s speed exceeds its speed in vacuum. Especially, because <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x115.png" xlink:type="simple"/></inline-formula> increases with time, enough long time later, light’s speed may greatly exceed its speed in vacuum.</p><p>This is not allowed in physics. As we know that the watershed between classical physics and modern physics is just on the invariance principle of light’s speed. Because the R-W metric violates this principle, it can not be used as the space-time frame for modern cosmology which is considered as the theory of relativity. Especially when the expansion speed of the universe is great, huge error will be caused.</p><p>As for the curve space with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x116.png" xlink:type="simple"/></inline-formula>, let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x117.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x118.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x119.png" xlink:type="simple"/></inline-formula>in (44), we obtain</p><disp-formula id="scirp.18173-formula1196"><graphic  xlink:href="http://html.scirp.org/file/2-4500069x120.png"  xlink:type="simple"/></disp-formula><p>or</p><disp-formula id="scirp.18173-formula1197"><label>(49)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x121.png"  xlink:type="simple"/></disp-formula><p>On the other hand, as we known that coordinate <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x122.png" xlink:type="simple"/></inline-formula> has no meaning of measurement in curved space. What is meaningful is proper distance. Suppose that an observer stays at the original point of coordinate system, the definition of proper distance for the R-W metric between observer and light’s source is [<xref ref-type="bibr" rid="scirp.18173-ref5">5</xref>].</p><disp-formula id="scirp.18173-formula1198"><label>(50)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x123.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x124.png" xlink:type="simple"/></inline-formula> equivalent to <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x125.png" xlink:type="simple"/></inline-formula> in the flat space. For illuminant material moving in the expansive universe, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x126.png" xlink:type="simple"/></inline-formula>does not change with time. The velocity of illumi-</p><p>nant material relative to observer is<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x127.png" xlink:type="simple"/></inline-formula>. By</p><p>considering (49), the velocity of light emitted by illuminant material moves in the curved space is</p><disp-formula id="scirp.18173-formula1199"><label>(51)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x128.png"  xlink:type="simple"/></disp-formula><p>So (51) still violates the principle of invariance of light’s speed. In fact, the four dimensional metric of flat space-time is</p><disp-formula id="scirp.18173-formula1200"><label>(52)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x129.png"  xlink:type="simple"/></disp-formula><p>by using co-moving coordinate <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x130.png" xlink:type="simple"/></inline-formula> in (52), we obtain</p><disp-formula id="scirp.18173-formula1201"><label>(53)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x131.png"  xlink:type="simple"/></disp-formula><p>It is completely different from the R-W metric (44) when<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x132.png" xlink:type="simple"/></inline-formula>. The metric (53) seems to be curved but is flat essentially. According to the principle of the Riemannian geometry, if we can find a method to turn a curved space into flat, the original space is flat essentially. If we can not find such method, the original space is a curved space in essence. It is obvious that we can not find a transformation to turn (52) into (45) when<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x133.png" xlink:type="simple"/></inline-formula>, the spatial part of (45) can not be flat!</p><p>On the other hand, the four dimensional metric in which three dimensional space has a constant curvature <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x134.png" xlink:type="simple"/></inline-formula> is</p><disp-formula id="scirp.18173-formula1202"><label>(54)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x135.png"  xlink:type="simple"/></disp-formula><p>by using co-moving coordinate in (54), we obtain</p><disp-formula id="scirp.18173-formula1203"><label>(55)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x136.png"  xlink:type="simple"/></disp-formula><p>Let<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x137.png" xlink:type="simple"/></inline-formula>, we reach (53) rather then (45). Therefore, if we use co-moving coordinate to describer the expansive universe in which the space is flat, we should use (53), rather than (45). If we describe the expansive universe with constant curvature, we should use (55), rather than (44).</p><p>Another result of using the R-W metric in cosmology is that it leads to the united universe time. In the R-W metric, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x138.png" xlink:type="simple"/></inline-formula>indicates that we have the same time for any spatial point in the expansive universe. This obviously violates special relativity. Because there is a relative motion speed between two objects in the expansive universe, there exists time delay between them according to special relativity. It is actually the result of the Newtonian mechanics to use the united universe time in cosmology. This is another reason why we say that the Friedmann equation is equivalent to the Newtonian mechanics.</p><p>However, it is easy to prove that if we use flat space- time metric (53) in the Einstein’s equation of gravity, the Einstein’s tensor would become zero with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x139.png" xlink:type="simple"/></inline-formula>. In this way, we can not describe the gravity field of the expansive universe. Therefore, both the R-W metric and the flat space-time metric are unsuitable for cosmology. We should look for other proper methods to describe the expansive universe.</p></sec><sec id="s3_3"><title>3.3. Dynamic Energy Momentum Tensor Should Be Used in Cosmology</title><p>The energy momentum tensor of ideal liquid is used in cosmology with the form</p><disp-formula id="scirp.18173-formula1204"><label>(56)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x140.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x141.png" xlink:type="simple"/></inline-formula> is the four dimensional velocity. In the standard cosmology, we take <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x142.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x143.png" xlink:type="simple"/></inline-formula> with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x144.png" xlink:type="simple"/></inline-formula>,<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x145.png" xlink:type="simple"/></inline-formula>. It means that we take static energy momentum tensor energy in the Einstein’s equation of gravity without considering material’s velocity.</p><p>This is an excessively simplified approximation. In fact, there exist relative velocities between materials and observers in the expansive universe. The most basic fact for cosmology is the Hubble’s red shift, which is explained as the kinematical effect caused by relative velocities be- tween observer and luminous material. If co-moving co- ordinate<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x146.png" xlink:type="simple"/></inline-formula>, material’s speed is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x147.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x148.png" xlink:type="simple"/></inline-formula>. In fact, on the left side of the Fiedmann equation, we have<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x149.png" xlink:type="simple"/></inline-formula>. How can we take <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x150.png" xlink:type="simple"/></inline-formula> on the right side of equation which contains energy momentum tensor? It is absolutely unjustifiable to use static energy momentum tensor to describe the expansive universe. In fact, if we use static energy momentum tensor to describe the expansive universe, what do we use to describer the static universe? This is a problem to make us embarrassing.</p><p>According general relativity, we can use arbitrary reference frame to describe the gravity field. By using common spherical coordinate system, the partial velocities of an object which moves along the radius direction are <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x151.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x152.png" xlink:type="simple"/></inline-formula>,<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x153.png" xlink:type="simple"/></inline-formula>. The forth dimensional velocities are (<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x154.png" xlink:type="simple"/></inline-formula>).</p><disp-formula id="scirp.18173-formula1205"><label>(57)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x155.png"  xlink:type="simple"/></disp-formula><p>To simplify discussion below, we use the R-W metric and take<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x156.png" xlink:type="simple"/></inline-formula>. For the expansive universe with uniform distribution of material, dynamic energy momentum tensors are</p><disp-formula id="scirp.18173-formula1206"><label>(58)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x157.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1207"><label>(59)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x158.png"  xlink:type="simple"/></disp-formula><p>Substituting them in the Einstein’s equation of gravity</p><disp-formula id="scirp.18173-formula1208"><label>(60)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x159.png"  xlink:type="simple"/></disp-formula><p>We get the motion equations of cosmology</p><disp-formula id="scirp.18173-formula1209"><label>(61)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x160.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1210"><label>(62)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x161.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1211"><label>(63)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x162.png"  xlink:type="simple"/></disp-formula><p>Substitute <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x163.png" xlink:type="simple"/></inline-formula> in the formulas, we get</p><disp-formula id="scirp.18173-formula1212"><label>(64)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x164.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1213"><label>(65)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x165.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1214"><label>(66)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x166.png"  xlink:type="simple"/></disp-formula><p>Take <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x167.png" xlink:type="simple"/></inline-formula> on the right sides but not on the left sides, we obtain the Fiedmann equation. But we can not do it in this way. Because <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x168.png" xlink:type="simple"/></inline-formula> is a constant, we have three ways to make (65) tenable. The first is to let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x169.png" xlink:type="simple"/></inline-formula> which describes the static universe. By considering the observation fact of the Hubble redshift, this is improper. The second is to take simultaneously</p><disp-formula id="scirp.18173-formula1215"><label>(67)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x170.png"  xlink:type="simple"/></disp-formula><p>Here A and B are constants. From (67), we obtain</p><disp-formula id="scirp.18173-formula1216"><label>(68)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x171.png"  xlink:type="simple"/></disp-formula><p>The result violates the Hubble law too. In addition, these velocities are inconsistent, so (68) is impossible. The third is to get the solution from (65)</p><disp-formula id="scirp.18173-formula1217"><label>(69)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x172.png"  xlink:type="simple"/></disp-formula><p>Substitute (69) in (64) and (66), we have</p><disp-formula id="scirp.18173-formula1218"><label>(70)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x173.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1219"><label>(71)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x174.png"  xlink:type="simple"/></disp-formula><p>by cancelling <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x175.png" xlink:type="simple"/></inline-formula> from two formulas above, we obtain at last</p><disp-formula id="scirp.18173-formula1220"><label>(72)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x176.png"  xlink:type="simple"/></disp-formula><p>The equation becomes so complicated that it is impossible to solve actually. On the other hand, because the right hand sides of (64)-(66) contain<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x177.png" xlink:type="simple"/></inline-formula>, if <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x178.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x179.png" xlink:type="simple"/></inline-formula> are still unrelated to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x180.png" xlink:type="simple"/></inline-formula>, we should have <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x181.png" xlink:type="simple"/></inline-formula> by solving the equations. The result contradicts with the origi- nal definition<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x182.png" xlink:type="simple"/></inline-formula>. In order to mate <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x183.png" xlink:type="simple"/></inline-formula> unrelated to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x184.png" xlink:type="simple"/></inline-formula>, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x185.png" xlink:type="simple"/></inline-formula>and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x186.png" xlink:type="simple"/></inline-formula> should be related to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x187.png" xlink:type="simple"/></inline-formula>. In this</p><p>way, the principle of cosmology can not hold again. The result means that we will be in dilemma if dynamic energy momentum tensor is used in cosmology.</p><p>Pioneers of cosmology must have considered this problem, so they had to use static energy momentum to establish the equation of cosmology. In the early stage of cosmology, the observed expansion speed of the universe was low, so the simplified motion equation could be suitable. When cosmology develops to now day’s level, we observe cosmic phenomena which take place in the high speed expansive processes such as the high red shift of supernova. The simplified Friedmann equation becomes unsuitable so that many difficulties appear in the standard cosmology at present. This is the main reason why we have to introduce the hypothesis of the accelerating expansion of the universe, dark energy and non-baryon dark material.</p></sec></sec><sec id="s4"><title>4. Velocity, Acceleration and Initial Conditions of the Universe Expansion</title><sec id="s4_1"><title>4.1. Velocity and Acceleration of the Universe Expansion</title><p>Because (72) can not be solved practically when dynamic energy momentum tensor is considered, we have to look for other method to describe the expansive universe. We prove below that based on the revised formula (25), the high red shift of supernova can be explained well. There- fore, we do not need the hypothesis of dark energy and the universe accelerating expansion again.</p><p>In principle, we can take the CMB as static reference to describe the universe expansion. Practically, we take the earth as static reference frame for convenience. Suppose that the universe material is distributed with spherical symmetry and uniform density<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x188.png" xlink:type="simple"/></inline-formula>. The static mass of sphere with radius R is<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x189.png" xlink:type="simple"/></inline-formula>. Similarly we have <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x190.png" xlink:type="simple"/></inline-formula> with radius r. According to the Newtonian theory, gravity acted on a small object located at point r with mass <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x191.png" xlink:type="simple"/></inline-formula> is [<xref ref-type="bibr" rid="scirp.18173-ref6">6</xref>]</p><disp-formula id="scirp.18173-formula1221"><label>(73)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x192.png"  xlink:type="simple"/></disp-formula><p>The formulas indicate that when mass <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x193.png" xlink:type="simple"/></inline-formula> is located outsider the sphere with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x194.png" xlink:type="simple"/></inline-formula>, the gravity acted on it is equal to that when the spherical mass is centralized at the center of sphere. When mass <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x195.png" xlink:type="simple"/></inline-formula> is located inside the sphere with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x196.png" xlink:type="simple"/></inline-formula>, the gravity acted on it is only related to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x197.png" xlink:type="simple"/></inline-formula>, having nothing to do with the mass distributed outside the radius r.</p><p>Suppose that the universe expands along the direction of radius. In the process, angle momentum L is equal to zero. We calculate gravity between a spherical shell with radius R and an object located at point <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x198.png" xlink:type="simple"/></inline-formula> with static mass <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x199.png" xlink:type="simple"/></inline-formula> and speed <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x200.png" xlink:type="simple"/></inline-formula> along radius direction. Suppose that <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x201.png" xlink:type="simple"/></inline-formula> satisfies (22) approximately, we use (22) to describe object’s effective mass. According to (23) and (25), we have</p><disp-formula id="scirp.18173-formula1222"><label>(74)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x202.png"  xlink:type="simple"/></disp-formula><p>Here<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x203.png" xlink:type="simple"/></inline-formula>. Let<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x204.png" xlink:type="simple"/></inline-formula>,</p><p><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x205.png" xlink:type="simple"/></inline-formula>, and taking the integral of (74), we get the total gravity that the expansive sphere with radius <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x206.png" xlink:type="simple"/></inline-formula> acts on an object located on the spherical surface with static mass <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x207.png" xlink:type="simple"/></inline-formula> and speed <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x208.png" xlink:type="simple"/></inline-formula></p><disp-formula id="scirp.18173-formula1223"><label>(75)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x209.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1224"><label>(76)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x210.png"  xlink:type="simple"/></disp-formula><p>On the other hand, according to special relativity, we have</p><disp-formula id="scirp.18173-formula1225"><label>(77)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x211.png"  xlink:type="simple"/></disp-formula><p>Based on (76) and (77), we get the acceleration of an object located on spherical surface</p><disp-formula id="scirp.18173-formula1226"><label>(78)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x212.png"  xlink:type="simple"/></disp-formula><p>The acceleration is just related to the mass inside the sphere, and unrelated to the mass outsider the sphere. We also consider (78) as the expansion speed of spherical surface with radius r. Let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x213.png" xlink:type="simple"/></inline-formula> and using relation <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x214.png" xlink:type="simple"/></inline-formula> in (78), we obtain</p><disp-formula id="scirp.18173-formula1227"><label>(79)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x215.png"  xlink:type="simple"/></disp-formula><p>Let<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x216.png" xlink:type="simple"/></inline-formula>, we have</p><disp-formula id="scirp.18173-formula1228"><label>(80)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x217.png"  xlink:type="simple"/></disp-formula><p>In the expansion process of the universe, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x218.png" xlink:type="simple"/></inline-formula>changes while spherical radius r changes. But spherical mass M is</p><p>unchanged with <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x219.png" xlink:type="simple"/></inline-formula>constant. We have <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x220.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x221.png" xlink:type="simple"/></inline-formula> or<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x222.png" xlink:type="simple"/></inline-formula>. Suppose that initial radius</p><p>is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x223.png" xlink:type="simple"/></inline-formula> (<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x224.png" xlink:type="simple"/></inline-formula>) and initial speed is<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x225.png" xlink:type="simple"/></inline-formula>, substituting the relation into (79) and take the integral. Let</p><disp-formula id="scirp.18173-formula1229"><label>(81)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x226.png"  xlink:type="simple"/></disp-formula><p>we get</p><disp-formula id="scirp.18173-formula1230"><label>(82)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x227.png"  xlink:type="simple"/></disp-formula><p>Let</p><disp-formula id="scirp.18173-formula1231"><label>(83)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x228.png"  xlink:type="simple"/></disp-formula><p>we have</p><disp-formula id="scirp.18173-formula1232"><label>(84)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x229.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1233"><label>(85)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x230.png"  xlink:type="simple"/></disp-formula><p>Because (81) can not be integrated directly, we need approximate method. When x is very small (<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x231.png" xlink:type="simple"/></inline-formula>), by developing (76) into the Taylor’s series in the region of<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x232.png" xlink:type="simple"/></inline-formula>, we obtain</p><disp-formula id="scirp.18173-formula1234"><label>(86)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x233.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1235"><label>(87)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x234.png"  xlink:type="simple"/></disp-formula><p>By considering (80), (87) becomes</p><disp-formula id="scirp.18173-formula1236"><label>(88)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x235.png"  xlink:type="simple"/></disp-formula><p>Substituting the formulas in (78) and (85), we obtain the formula of acceleration and speed of the universe expansion</p><disp-formula id="scirp.18173-formula1237"><label>(89)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x236.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1238"><label>(90)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x237.png"  xlink:type="simple"/></disp-formula></sec><sec id="s4_2"><title>4.2. Initial Condition of the Universe Expansion</title><p>In the discussion above, we assume that material is only acted by gravity. However, practical situation is that strong, weak and electromagnetic interactions could not be neglected in the early phase of the universe during which material density was great. Even more, some unknown interaction may exist.</p><p>According to the theory of Einstein’s theory, material may be compressed into infinite density by gravity. How- ever, infinite density is unimaginable. In fact, the author had proved that due to use the improper boundary condition of flat space-time in the gravity theory of curved space-time, the current theory of singularity black hole is wrong. By strict calculation based on the Einstein’s equation of gravity and curved boundary condition, singular black hole with infinity density do not exist [7,8]. By the same reasons, the fashionable idea that the universe originated from infinite small point is also impossible.</p><p>In order to avoid infinite density, we assume that there exist a certain mechanism so that material sphere with mass M can only be compressed to a finite radius r<sub>0</sub>. In this way, the motion equation of the universe expansion should be revised as</p><disp-formula id="scirp.18173-formula1239"><label>(91)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x238.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x239.png" xlink:type="simple"/></inline-formula> is gravity and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x240.png" xlink:type="simple"/></inline-formula> is the sum of other forces. For convenience, we simplify</p><disp-formula id="scirp.18173-formula1240"><label>(92)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x241.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x242.png" xlink:type="simple"/></inline-formula>is undetermined function. It corresponds to an infinite potential barrier with radius r<sub>0</sub> on which the spherical surface can not be contracted further. Meanwhile, by the action of <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x243.png" xlink:type="simple"/></inline-formula> at the spherical surface with radius<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x244.png" xlink:type="simple"/></inline-formula>, the process of contraction become expansion and the surface moves with a positive acceleration. When<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x245.png" xlink:type="simple"/></inline-formula>, other forces become zero and only gravity acts. When<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x246.png" xlink:type="simple"/></inline-formula>, it is just the so-called big bang of the universe from an infinite singular point. By considering (92), (79) becomes</p><disp-formula id="scirp.18173-formula1241"><label>(93)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x247.png"  xlink:type="simple"/></disp-formula><p>The integral of (93) is</p><disp-formula id="scirp.18173-formula1242"><label>(94)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x248.png"  xlink:type="simple"/></disp-formula><p>Let</p><disp-formula id="scirp.18173-formula1243"><label>(95)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x249.png"  xlink:type="simple"/></disp-formula><p><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x250.png" xlink:type="simple"/></inline-formula>represents the initial condition of the universe expansion. For different objects located at different position r now days, their initial positions <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x251.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x252.png" xlink:type="simple"/></inline-formula> are different. We will discuss how to decide <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x253.png" xlink:type="simple"/></inline-formula> later. In this way, (94) becomes</p><disp-formula id="scirp.18173-formula1244"><label>(96)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x254.png"  xlink:type="simple"/></disp-formula><p>Under the condition<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x255.png" xlink:type="simple"/></inline-formula>, by considering (86) and (88), the formulas of velocity and acceleration can be written as</p><disp-formula id="scirp.18173-formula1245"><label>(97)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x256.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1246"><label>(98)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x257.png"  xlink:type="simple"/></disp-formula><p>Here<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x258.png" xlink:type="simple"/></inline-formula>. If expansive velocity is great, we should use (78) and (96) directly.</p></sec></sec><sec id="s5"><title>5. Red Shifts of Cosmology and Hubble Diagram of Supernova</title><sec id="s5_1"><title>5.1. Red Shift of Cosmology</title><p>According to the Doppler’s formula, when celestial body moves along radius direction, we have relation between speed and red shift</p><disp-formula id="scirp.18173-formula1247"><label>(99)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x259.png"  xlink:type="simple"/></disp-formula><p>Suppose that observer is located at the origin point of flat reference frame, the distance between observer and celestial body is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x260.png" xlink:type="simple"/></inline-formula> at moment<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x261.png" xlink:type="simple"/></inline-formula>. In the expanding process of the universe, celestial body moves from <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x262.png" xlink:type="simple"/></inline-formula> to <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x263.png" xlink:type="simple"/></inline-formula> with<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x264.png" xlink:type="simple"/></inline-formula>, while the light travels from <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x265.png" xlink:type="simple"/></inline-formula> to observer along opposite direction. Suppose light’s speed is invariable in the process, we have following relation</p><disp-formula id="scirp.18173-formula1248"><label>(100)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x266.png"  xlink:type="simple"/></disp-formula><p>According to (96), we have</p><disp-formula id="scirp.18173-formula1249"><label>(101)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x267.png"  xlink:type="simple"/></disp-formula><p>The real distance between observer and celestial body is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x268.png" xlink:type="simple"/></inline-formula> at present moment<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x269.png" xlink:type="simple"/></inline-formula>. We know the universe material density <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x270.png" xlink:type="simple"/></inline-formula> at time<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x271.png" xlink:type="simple"/></inline-formula>, but do not know its value <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x272.png" xlink:type="simple"/></inline-formula> at arbitrary time t. By considering relation <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x273.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x274.png" xlink:type="simple"/></inline-formula>, we write (80) as</p><disp-formula id="scirp.18173-formula1250"><label>(102)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x275.png"  xlink:type="simple"/></disp-formula><p>Using (102) in (101) and taking the integral, we can obtain the relation in principle</p><disp-formula id="scirp.18173-formula1251"><label>(103)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x276.png"  xlink:type="simple"/></disp-formula><p>In the formulas above, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x277.png" xlink:type="simple"/></inline-formula>, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x278.png" xlink:type="simple"/></inline-formula>and Z are known through observations, but<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x279.png" xlink:type="simple"/></inline-formula>, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x280.png" xlink:type="simple"/></inline-formula>and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x281.png" xlink:type="simple"/></inline-formula> are unknown. By the relation<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x282.png" xlink:type="simple"/></inline-formula>, we can determinate<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x283.png" xlink:type="simple"/></inline-formula>. By</p><p>connecting (100) and (103), we can determinate <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x284.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x285.png" xlink:type="simple"/></inline-formula>. (101) can only be calculated by numerical method through computer. By taking G = 6.67 &#215; 10<sup>?</sup><sup>11</sup>, r<sub>0</sub> = y<sub>0</sub> &#215; 10<sup>26</sup> m, r<sub>1</sub> = y<sub>1</sub> &#215; 10<sup>26</sup> m and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x286.png" xlink:type="simple"/></inline-formula> = b&#215; 10<sup>?26</sup> kg/m<sup>3</sup>, we have</p><disp-formula id="scirp.18173-formula1252"><label>(104)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x287.png"  xlink:type="simple"/></disp-formula><p>We use x as basic variable to calculate y<sub>0</sub> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x288.png" xlink:type="simple"/></inline-formula> in which b, Z and y<sub>1</sub> are input parameters. According to this paper, we actually deduce the initial situations of the universe expansion reversely based on the present observations of red shift and distances. In other words, as long as the initial conditions of the universe expansion are known, we can know its current situations.</p></sec><sec id="s5_2"><title>5.2. The Red Shift of Ia Supernova</title><p>In <xref ref-type="fig" rid="fig1">Figure 1</xref>, the curved line with <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x289.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x290.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x291.png" xlink:type="simple"/></inline-formula> represents practical relation between red shift and distance of Ia supernova at the early period of time t. According to photometry measurement, the density of luminous material in the universe is about <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x292.png" xlink:type="simple"/></inline-formula> kg/m<sup>3</sup> at present day. Because there exist a great mount of non-luminous material, we suppose that practical material is 10 times more than luminous material and let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x293.png" xlink:type="simple"/></inline-formula> kg/m<sup>3</sup>. In <xref ref-type="fig" rid="fig1">Figure 1</xref>, we take <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x294.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x295.png" xlink:type="simple"/></inline-formula> in which <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x296.png" xlink:type="simple"/></inline-formula> is luminosity distance with unit length<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x297.png" xlink:type="simple"/></inline-formula>. But the concept of luminosity distance is unnecessary in this paper for our discussion is based on flat space-time. So we need to transform <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x298.png" xlink:type="simple"/></inline-formula> to real distance r.</p><p>The curved line in <xref ref-type="fig" rid="fig2">Figure 2</xref> shows the relations between red-shifts, distances and parameters of initial condition of Ia supernova. The vertical coordinate is the values of<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x299.png" xlink:type="simple"/></inline-formula>. The bottom horizontal coordinate is the value of red-shift. On the upside, under the line of horizontal coordinate are the values of distance r, above the line is the values of r<sub>0</sub>. For Z = 1 and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x300.png" xlink:type="simple"/></inline-formula>, we get<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x301.png" xlink:type="simple"/></inline-formula>. By the numerical calculation, we obtain <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x302.png" xlink:type="simple"/></inline-formula>and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x303.png" xlink:type="simple"/></inline-formula>. For Z = 0.5 and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x304.png" xlink:type="simple"/></inline-formula> corresponding to r<sub>1</sub> = 0.67 &#215; 10<sup>26</sup> m, we obtain <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x305.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x306.png" xlink:type="simple"/></inline-formula>. For Z = 0.1 and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x307.png" xlink:type="simple"/></inline-formula> corresponding to r<sub>1</sub> = 0.15 &#215; 10<sup>26</sup> m, we obtain r = 0.16 &#215; 10<sup>26</sup> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x308.png" xlink:type="simple"/></inline-formula>.</p><p>In this way, we can explain the high red shift of Ia supernova well. The hypotheses of dark energy and the accelerating expansion of the universe become unnecessary. The universe began its expansion from a finite volume, rather than from a singularity.</p></sec></sec><sec id="s6"><title>6. Revised Equation of Cosmology</title><p>In order to compare with the equations of cosmology, we now transform (97) and (98) to the form of the Friedmann equation. Suppose that the universe is a uniform</p><p>sphere with density<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x311.png" xlink:type="simple"/></inline-formula>. We define <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x312.png" xlink:type="simple"/></inline-formula> in which <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x313.png" xlink:type="simple"/></inline-formula> is a parameter unrelated with time. Let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x314.png" xlink:type="simple"/></inline-formula> represent today’s time, we have <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x315.png" xlink:type="simple"/></inline-formula> and can write (80) as</p><disp-formula id="scirp.18173-formula1253"><label>(105)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x316.png"  xlink:type="simple"/></disp-formula><p>Here<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x317.png" xlink:type="simple"/></inline-formula>. Under the condition<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x318.png" xlink:type="simple"/></inline-formula>, (100) can be written as</p><disp-formula id="scirp.18173-formula1254"><label>(106)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x319.png"  xlink:type="simple"/></disp-formula><p>Similarly, let<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x320.png" xlink:type="simple"/></inline-formula>, we can write (97) as</p><disp-formula id="scirp.18173-formula1255"><label>(107)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x321.png"  xlink:type="simple"/></disp-formula><p>On the other hand, the Friedmann equation containing cosmic constant <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x322.png" xlink:type="simple"/></inline-formula> are</p><disp-formula id="scirp.18173-formula1256"><label>(108)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x323.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1257"><label>(109)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x324.png"  xlink:type="simple"/></disp-formula><p>Here <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x325.png" xlink:type="simple"/></inline-formula> is considered as a constant energy density corresponding to vacuum and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x326.png" xlink:type="simple"/></inline-formula> in the current cosmology. Comparing (106) and (107) with (108) and (109), we have</p><disp-formula id="scirp.18173-formula1258"><label>(110)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x327.png"  xlink:type="simple"/></disp-formula><disp-formula id="scirp.18173-formula1259"><label>(111)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x328.png"  xlink:type="simple"/></disp-formula><p>It is obvious that after (110) and (111) are used, revised equations in this paper are with the same form with the Freidmann equation. The differences are that <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x329.png" xlink:type="simple"/></inline-formula> is not a constant, <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x330.png" xlink:type="simple"/></inline-formula>and p are also related to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x331.png" xlink:type="simple"/></inline-formula>. In order to be consistent with the observation of Ia supernova’s red shift, the current theory have to assume <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x332.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x333.png" xlink:type="simple"/></inline-formula>, so that we have to think that the universe is pushed by repulsive force and do accelerating expansion. According to this paper, we always have<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x334.png" xlink:type="simple"/></inline-formula>, so there is no repulsive force and accelerating expansion again. Because the forms of differential equations (106) and (107) are very complex, it is more convenience for us to use (97) and (98) directly to do calculations.</p></sec><sec id="s7"><title>7. The Hubble Constant, Dark Material and the Universe Age</title><sec id="s7_1"><title>7.1. The Hubble Constant</title><p>According to (97), we have</p><disp-formula id="scirp.18173-formula1260"><label>(112)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x335.png"  xlink:type="simple"/></disp-formula><p>Let <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x336.png" xlink:type="simple"/></inline-formula> represent the equivalent density of the universe</p><disp-formula id="scirp.18173-formula1261"><label>(113)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x337.png"  xlink:type="simple"/></disp-formula><p>We get</p><disp-formula id="scirp.18173-formula1262"><label>(114)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x338.png"  xlink:type="simple"/></disp-formula><p>At present <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x339.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x340.png" xlink:type="simple"/></inline-formula>, the Hubble constant is</p><disp-formula id="scirp.18173-formula1263"><label>(115)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x341.png"  xlink:type="simple"/></disp-formula><p>We see that <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x342.png" xlink:type="simple"/></inline-formula> is related to <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x343.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x344.png" xlink:type="simple"/></inline-formula>, not a real constant even under condition<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x345.png" xlink:type="simple"/></inline-formula>. This is the reason why we can not determinate the Hubble constant precisely up to present days.</p><p>In fact, only taking the first and last items in (98), we obtain the result of the Newtonian theory</p><disp-formula id="scirp.18173-formula1264"><label>(116)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x346.png"  xlink:type="simple"/></disp-formula><p>Taking <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x347.png" xlink:type="simple"/></inline-formula> = 2&#215; 10<sup>?26</sup> kg/m<sup>3</sup> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x348.png" xlink:type="simple"/></inline-formula>, we get<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x349.png" xlink:type="simple"/></inline-formula>. In cosmology, we generally take <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x350.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x352.png" xlink:type="simple"/></inline-formula><inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x351.png" xlink:type="simple"/></inline-formula>. We get <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x353.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x354.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x355.png" xlink:type="simple"/></inline-formula> according to (116). In the calculation, we consider r as the present position of luminous celestial, without considering its practical position to be r<sub>0</sub>. For the situation with Z = 1 and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x356.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x357.png" xlink:type="simple"/></inline-formula>, according to (116), the result is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x358.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x359.png" xlink:type="simple"/></inline-formula>. The result indicates that even though based on the Newtonian theory of gravity, we can also explain the high red shift of the Ia Supernova by taking different <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x360.png" xlink:type="simple"/></inline-formula> for different objects. It is also unnecessary for us to introduce the concept of dark energy by introducing the effect of initial conditions.</p><p>For <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x361.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x362.png" xlink:type="simple"/></inline-formula>, by using (96) for accurate numerical calculation, the result is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x363.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x364.png" xlink:type="simple"/></inline-formula> and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x365.png" xlink:type="simple"/></inline-formula> which is similar to that based on (116). But for the situations of high red shift, the differences of results are large.</p></sec><sec id="s7_2"><title>7.2. Non-Baryon Dark Material</title><p>According to the theory of nuclei synthesis in cosmology, relative density of baryon is<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x366.png" xlink:type="simple"/></inline-formula>, in which <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x367.png" xlink:type="simple"/></inline-formula> is baryon’s density and <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x368.png" xlink:type="simple"/></inline-formula> is total density of all material. We have relation [<xref ref-type="bibr" rid="scirp.18173-ref9">9</xref>]</p><disp-formula id="scirp.18173-formula1265"><label>(117)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x369.png"  xlink:type="simple"/></disp-formula><p>Take <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x370.png" xlink:type="simple"/></inline-formula>which corresponds to<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x371.png" xlink:type="simple"/></inline-formula>, we have <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x372.png" xlink:type="simple"/></inline-formula> = 7.9&#215; 10<sup>?27</sup> kg/m<sup>3</sup> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x373.png" xlink:type="simple"/></inline-formula>. Practical observation is<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x374.png" xlink:type="simple"/></inline-formula>, so the theory indicates that our universe is mainly composed of non- baryon material. However, according to this paper, by considering the existence of parameter<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x375.png" xlink:type="simple"/></inline-formula> in (115), it is enough for us to take <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x376.png" xlink:type="simple"/></inline-formula>2 &#215; 10<sup>?27</sup> kg/m<sup>3</sup> and get <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x377.png" xlink:type="simple"/></inline-formula> <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x378.png" xlink:type="simple"/></inline-formula> and<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x379.png" xlink:type="simple"/></inline-formula>. We do not need the hypothesis of non-baryon dark material. At least, we do not need to assume that non-baryon dark material is 5 ~ 6 times more than normal baryon material in the universe if non-baryon dark material exists actually.</p></sec><sec id="s7_3"><title>7.3. The Age of the Universe</title><p>We consider the universe as a material sphere with radius <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x380.png" xlink:type="simple"/></inline-formula> at initial moment, which is about the distance between the sun and the earth. Long enough later, an observer located at the original point of reference frame receives the light omitted from a celestial body on the spherical surface with radius <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x381.png" xlink:type="simple"/></inline-formula> kg/m<sup>3</sup> and find its red shift is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x382.png" xlink:type="simple"/></inline-formula> at time<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x383.png" xlink:type="simple"/></inline-formula>. Suppose that the material density of the universe is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x384.png" xlink:type="simple"/></inline-formula> at present, the initial density inside the sphere is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x385.png" xlink:type="simple"/></inline-formula> kg/m<sup>3</sup>, equal to the density of neutron star. According to the calculation before, the celestial body has moved to the position <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x386.png" xlink:type="simple"/></inline-formula> m at present moment. We consider this distance as the radius of the observable universe and substitute corresponding value <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x387.png" xlink:type="simple"/></inline-formula> to following formula to calculate the time during which the universe expands from radius <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x388.png" xlink:type="simple"/></inline-formula> m to <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x389.png" xlink:type="simple"/></inline-formula> m.</p><disp-formula id="scirp.18173-formula1266"><label>(118)</label><graphic position="anchor" xlink:href="http://html.scirp.org/file/2-4500069x390.png"  xlink:type="simple"/></disp-formula><p>The result is <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x391.png" xlink:type="simple"/></inline-formula> billion years. But this value is not sensitive to small initial radius. Taking<inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x392.png" xlink:type="simple"/></inline-formula>, equal to the radius of the Milky Way galaxy, the result is the almost same. It means that the age of the universe mainly depends on the later expansive process.</p><p>Using (118) to calculates the time during which the universe radius expanses from 1.23 &#215; 10<sup>26</sup> m to 1.95 &#215; 10<sup>26</sup> m, the result is 13 billion years, so the time during which the radius of the universe expanses from <inline-formula><inline-graphic xlink:href="http://html.scirp.org/file/2-4500069x393.png" xlink:type="simple"/></inline-formula> m to 1.23 &#215; 10<sup>26</sup> m is 17.8 billion years. This is just the universe age we consider at present. In the present cosmology, the universe age is estimated to be about 10 ~ 15 billion years, too short to the formation of galaxies [<xref ref-type="bibr" rid="scirp.18173-ref10">10</xref>]. The problem does not exist according to this paper.</p></sec></sec><sec id="s8"><title>8. Conclusions</title><p>By transforming the geodesic equation of the Schwarzs- child solution of the Einstein’s equation into flat space- time to describe, the revised Newtonian formula of gravity and the revised equation of cosmology are obtained. The singularity problem in the Einstein’s theory of gravity described in curved space-time is eliminated thoroughly.</p><p>Because using two improper and approximate conditions, the Freidmann equation becomes the result of the Newtonian theory of gravity actually. It is only suitable to describe the low speed expansive processes of the universe, unsuitable to describe the high speed expansion. The equation of cosmology needs relativity revision.</p><p>By using the revised Newtonian formula of gravity, the revised equation of cosmology is obtained. The high red-shift of supernova can be well explained. It is unnecessary for us to introduce the hypotheses of the universe accelerating expansion and dark energy. It is also unnecessary for us to assume that non-baryon dark material is 5 - 6 times more than normal baryon dark material if it exists actually. Many problems existing in cosmology including the problem of the universe age can be resolved well.</p><p>In this way, the theory of gravity returns to the traditional form of dynamic description and becomes normal one. The revised equation can be used as the foundation of more rational cosmology.</p></sec></body><back><ref-list><title>References</title><ref id="scirp.18173-ref1"><label>1</label><mixed-citation publication-type="other" xlink:type="simple">N. Rosen, “General Relativity and Flat Space,” Physical Review, Vol. 57, No. 2, 1940, pp. 147-150.  
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