<?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">JMP</journal-id><journal-title-group><journal-title>Journal of Modern Physics</journal-title></journal-title-group><issn pub-type="epub">2153-1196</issn><publisher><publisher-name>Scientific Research Publishing</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.4236/jmp.2013.49158</article-id><article-id pub-id-type="publisher-id">JMP-36564</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>
 
 
  Rapid Quantum Search Algorithm
 
</article-title></title-group><contrib-group><contrib contrib-type="author" xlink:type="simple"><name name-style="western"><surname>ehuda</surname><given-names>Roth</given-names></name><xref ref-type="aff" rid="aff1"><sub>1</sub></xref><xref ref-type="corresp" rid="cor1"><sup>*</sup></xref></contrib></contrib-group><aff id="aff1"><label>1</label><addr-line>Oranim Academic College, K. Tivon, Israel</addr-line></aff><author-notes><corresp id="cor1">* E-mail:<email>yudroth@gmail.com</email></corresp></author-notes><pub-date pub-type="epub"><day>03</day><month>09</month><year>2013</year></pub-date><volume>04</volume><issue>09</issue><fpage>1176</fpage><lpage>1179</lpage><history><date date-type="received"><day>April</day>	<month>9,</month>	<year>2013</year></date><date date-type="rev-recd"><day>May</day>	<month>16,</month>	<year>2013</year>	</date><date date-type="accepted"><day>June</day>	<month>12,</month>	<year>2013</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>
 
 
   The collapse phenomenon, the parallelism principle and states correlation are used to define a type of a Grover rapid search engine. In our approach, the observer’s query and the Grover-unsorted-data are stored in different memories where the global state is represented by a tensor product of the associated states. In the proposed formalism, each <b>query-state</b> input activates an adjusted operator that implements the unsorted state in an appropriate 2-D Grover representation. It will be shown that once the representation is set, it takes mainly two operations to complete the whole query search. This seems to be a very efficient search algorithm. 
 
</p></abstract><kwd-group><kwd>Grover Algorithm; Parallel Space</kwd></kwd-group></article-meta></front><body><sec id="s1"><title>1. Introduction</title><p>Quantum coherence, together with the superposition principle, gives rise to the parallelism concept for which processing a single state is like acting simultaneously on all states that participate in the superposition [1,2]. It is also known that a key role in speeding up quantum algorithms is played by multi-particle entanglement [<xref ref-type="bibr" rid="scirp.36564-ref3">3</xref>]. These entanglement and parallelism concepts enable quantum algorithms such as Shor’s factoring, which provide options for very fast computers [<xref ref-type="bibr" rid="scirp.36564-ref4">4</xref>].</p><p>In addition, quantum superposition of coherence qubits has the advantage of maintaining enormous databases by a single state. It is shown that this superposition of qubits can be applied to an efficient database-finding algorithm and in particular the Grover algorithm that defines a &#160;possibility for an efficient search engine [5-7]. The advantage of using quantum memory is shown in [8-10] with the definition of a model for which binary pat-&#160; terns of n-bits are stored in the quantum superposition of the appropriate subset of the computational basis of n-qbits.</p><p>The grover algorithm divides the Hilbert space into two segments: the requested query (denoted by the state<img src="4-7501290\12795380-3e5c-461c-9c17-022b9a6c88a9.jpg" />)</p><p>and all the other records<img src="4-7501290\ec982586-7bfb-4b57-94a2-acd5fab40875.jpg" />. The initial state is a maximal unsorted state <img src="4-7501290\ff402164-7106-49a5-8f1a-f5d197bef21b.jpg" /> while the Grover Oracle is a unitary transformation (logical gate)</p><p>that rotates the unsorted state until after a relatively small number of iteration<img src="4-7501290\f4b76b6e-659d-4823-8158-31704cae7f17.jpg" />. The probability of detecting the requested query is almost one. Then, a measurement terminates a successful search.</p><p>The selection of the 2-D basis <img src="4-7501290\27d7e70d-2e9a-4fd1-bf26-852b0ef3ce6a.jpg" /> and <img src="4-7501290\6db1311b-693d-4c71-bd3c-703791820f0c.jpg" /> yields that each search has to be associated with an exclusive 2-D representation such that preparing the appropriate representation corresponds with a primary knowledge about the searched state. In that sense, the Grover algorithm is not a pure search algorithm. Actually, it’s more likely an “inverting a function” meaning that if we have a function <img src="4-7501290\9edd44d2-335f-4ae4-829e-584b407a0bc0.jpg" /> that can be evaluated on a quantum computer, this algorithm allows us to calculate <img src="4-7501290\741752ce-0094-4b0d-be60-dd5c5b39a9e0.jpg" /> when given <img src="4-7501290\c87a7d73-4199-4b76-a928-d0ad19445a14.jpg" /> [<xref ref-type="bibr" rid="scirp.36564-ref11">11</xref>]. If we consider the <img src="4-7501290\f3614123-81a9-423b-a3f5-3c2932d6daaa.jpg" /> and <img src="4-7501290\649037a9-43bb-47cf-ad0d-11b3102746f1.jpg" /> as vectors, the algorithm corresponds with rotating the <img src="4-7501290\404f52f7-71b6-4a19-9be6-da2d9b4c9194.jpg" /> state with respect to the <img src="4-7501290\e1f14be8-ad22-430a-9173-8e24204a8940.jpg" /> state. This is an equivalent way to represent the constrain of a primary knowledge concerning the searched state <img src="4-7501290\feac854d-d3ff-4239-ac10-1ed35830ba48.jpg" /> [<xref ref-type="bibr" rid="scirp.36564-ref12">12</xref>]. In order to overcome this obstacle, we introduce a parallel space (like another memory component) which is also spanned by the records states type <img src="4-7501290\23211d13-6fdf-4846-951a-a8614b5e0347.jpg" /> (the subscript <img src="4-7501290\f6cd86d4-22d9-421b-a929-c96bd7a77ae0.jpg" /> stand for the observer which determines the searched item) but unlike the register state (which belongs to what we refer to a r-space) that is occupied with the unsorted state, this o-space represents the observer search selection of a definite single record state, say,<img src="4-7501290\abada10b-d4e7-4386-b1ae-37014ba7d938.jpg" />. Thus, eventually, the searched item is well defined but only among the observer parallel space and definitely not to the other search component. We will present a scheme which shows that by correlating the observer state with the unsorted state, the later will be represented in the appropriate 2D representation. Once the unsorted state is prepared, we introduce a rapid search algorithm.</p></sec><sec id="s2"><title>2. Concepts Formulation</title><p>Searching a record corresponds with introducing the search machine with a query. A successful search ends with the presentation of the related data. In our approach the query is introduced thorough a state while the related data output is associated with an operator-eigenvalues rather than eigenstates.</p><p>To be more specific, suppose that the search machine possesses N states <img src="4-7501290\a0cb8c47-6871-422d-858d-f861f66df4e0.jpg" /> where each state presents a possible query. The measurement output is associated with the projective operator:</p><disp-formula id="scirp.36564-formula100048"><label>(1)</label><graphic position="anchor" xlink:href="4-7501290\c533df08-dc19-474b-ad25-e52ab8cc628b.jpg"  xlink:type="simple"/></disp-formula><p>with the corresponding eigenvalues<img src="4-7501290\eeae7644-c8fd-4b77-a400-25a22c375792.jpg" />.</p><p>A measurement result is the readable content, namely the eigenvalues rather than the eigenstates. Therefore, we propose that while the query request is introduced through a state, the relevant record information is expressed through the eigenvalues.</p><p>There are few possibilities to represent a data. It can be presented numerically or through a string of symbols. Indeed the current mathematical formulation allows us to introduce a symbolic eigenvalues-eigensymbols, that is, a string of symbols instead of a numeric value as shown in the following example:</p><p>Suppose that we search for information concerning Albert Einstein from an N number of records. The request is then coded into a state<img src="4-7501290\3eac244c-0d6b-4114-b537-8765d0211e9f.jpg" />. We can present the 2D-projective-operator:</p><disp-formula id="scirp.36564-formula100049"><label>(2)</label><graphic position="anchor" xlink:href="4-7501290\bc144bb7-dee1-42ab-829f-1c463a3f16da.jpg"  xlink:type="simple"/></disp-formula><p>If <img src="4-7501290\bb0353c0-a217-4ab5-852e-798b16ddfb76.jpg" /> is the input state then the result will be the</p><p><img src="4-7501290\1c5dc179-9820-4069-b9b1-b0506fdb8d9e.jpg" />, that is</p><disp-formula id="scirp.36564-formula100050"><label>(3)</label><graphic position="anchor" xlink:href="4-7501290\cfade68b-c36f-4c78-bcef-3395ac6f4680.jpg"  xlink:type="simple"/></disp-formula><p>All other states of the orthogonal basis, <img src="4-7501290\9f35c278-9932-4aa0-a968-8e4ffe0b123d.jpg" />, will yields the string<img src="4-7501290\315586a6-2369-48ba-ab97-0e232254472e.jpg" />:</p><disp-formula id="scirp.36564-formula100051"><label>(4)</label><graphic position="anchor" xlink:href="4-7501290\6841768b-c266-446c-afc5-6f88001ec47b.jpg"  xlink:type="simple"/></disp-formula><p>Note that this mathematical formalism allows us to present the output with many ways. For example the output can be a link to a relevant computer site. For that case the link can be represented by a Links-Operator- <img src="4-7501290\7bbdff84-e739-4bc5-8f81-cb8de9ac97a0.jpg" /> such that:</p><disp-formula id="scirp.36564-formula100052"><label>(5)</label><graphic position="anchor" xlink:href="4-7501290\1788d34d-f6cb-480f-a901-78c295acc5bf.jpg"  xlink:type="simple"/></disp-formula><p>If the observer query is<img src="4-7501290\12ac29ab-fdbc-4bed-b51f-6a64e639fb10.jpg" />, then we obtain</p><disp-formula id="scirp.36564-formula100053"><label>(6)</label><graphic position="anchor" xlink:href="4-7501290\44a5a625-6156-48fc-b651-2b35b7f37cf1.jpg"  xlink:type="simple"/></disp-formula><p>Once the machine recognize the <img src="4-7501290\6ca2b38a-58ce-4d3f-9b5b-d495d8bb50bc.jpg" /> state it activates the link operator <img src="4-7501290\6fdc8dc2-311a-4c7b-a618-24ee1de3c545.jpg" /> to present or link to the relevant site. For other cases the observer receive the text massage “Record not found”.</p></sec><sec id="s3"><title>3. The Machine Processor</title><sec id="s3_1"><title>3.1. The Observer Input</title><p>As in the grover algorithm [<xref ref-type="bibr" rid="scirp.36564-ref6">6</xref>] the register is occupied with an <img src="4-7501290\a79a920d-3917-4b55-83ce-28f0b81f7cae.jpg" /> unsorted records state:</p><disp-formula id="scirp.36564-formula100054"><label>(7)</label><graphic position="anchor" xlink:href="4-7501290\6100791b-9a18-48e3-98e7-0b7fc8c54508.jpg"  xlink:type="simple"/></disp-formula><p>where states that are related to the register component are denoted by the subscript<img src="4-7501290\e866b53e-1dc0-4f97-84c4-2ec1a38470b3.jpg" />.</p><p>The Grover search algorithm shrinks the <img src="4-7501290\b9fb4d35-d84b-47c0-bbba-8c0091519df2.jpg" />-records basis into a 2-D space, spanned by the states<img src="4-7501290\cef0d642-64d2-4c92-9722-0ff27d8ec922.jpg" />—the state under the search and the state<img src="4-7501290\5374a68b-45cf-408c-9e06-d12623d278f6.jpg" />—a superposition of all the other states. Consequently each search is associated with an exclusive 2-D representation such that preparing the appropriate representation corresponds with a primary knowledge about the searched state. In that sense the Grover algorithm is not a pure search algorithm. Actually it more accurate to describe the Grover algorithm as “inverting a function” meaning that if we have a function y = f(x) that can be evaluated on a quantum computer, this algorithm allows us to calculate x when given y [<xref ref-type="bibr" rid="scirp.36564-ref11">11</xref>].</p><p>If we consider the <img src="4-7501290\6d82a53f-084a-4fa3-9704-850b32d1ed89.jpg" /> and <img src="4-7501290\94bf074a-47eb-4303-8bae-433bcea5b12a.jpg" /> as vectors, the algorithm corresponds with rotating the <img src="4-7501290\ff993a8f-9863-4b7d-9feb-6656beb32581.jpg" /> state with respect to the <img src="4-7501290\1e5430be-8ceb-4600-8f80-75126e7830bf.jpg" /> state. This is an equivalent way to represent the constrain of a primary knowledge concerning the searched state <img src="4-7501290\1aa49041-ed05-46d4-b4e2-4c4d24d9c553.jpg" /> as nicely described in ref. [<xref ref-type="bibr" rid="scirp.36564-ref12">12</xref>]:</p><p>“Each Classical Walk step is almost Target-blind; meaning that it does not depend on what the searched target is, except in deciding whether to stop or go on with the search. It’s as if we were moving from some original binary code 0000 to the searched target in a dark room, taking small blind steps, until we hit the target. Once we hit the target, we recognize it as such and stop.</p><p>Now note that each Grover step is NOT an almost Target-blind; in fact, each Grover step is a rotation by a small angle <img src="4-7501290\9eca9451-aca4-4865-9413-ce9ba43371f3.jpg" /> in the plane that contains the unsorted state vector <img src="4-7501290\d17b8bf3-d1ce-4005-8af6-f165df23aa18.jpg" /> and the target state<img src="4-7501290\0d70b2dd-cbec-48c0-8255-fdccd5af47a6.jpg" />, where <img src="4-7501290\e4ec0ea3-2853-4351-a036-e50b005b1796.jpg" /> depends on the angle between <img src="4-7501290\e1300f89-c347-4d2d-90c2-fd82d09a06f5.jpg" /> and<img src="4-7501290\0b087067-eeeb-440f-91ce-03a8e8f9584e.jpg" />. So the Grover steps are not almost Target-blind. Far from it.”</p><p>As mentioned before, transforming the algorithm into a real search engine corresponds with introducing a parallel space, that is, an additional memory component. Likewise the records space it is spanned by the records states type <img src="4-7501290\eab57cea-37f1-48d9-b3b1-cd399032bb9b.jpg" /> (the subscript <img src="4-7501290\f49449b0-5002-4e9f-93de-b8f3c0d8be47.jpg" /> stand for the observer which determine the searched item) but unlike the rspace, this o-space represents the observer search selection of a definite single record state<img src="4-7501290\b3d78899-7d0f-46e6-9c16-45564e9fc981.jpg" />. Thus, eventually, the searched item is well know but only in the observer parallel space and definitely not by the other search component.</p><p>Suppose that by searching a <img src="4-7501290\d98fdec9-6f68-47f1-87ed-13fb028842ea.jpg" />-record, the observer defines the state<img src="4-7501290\2b5e6649-d84a-43f0-8a26-9159804a28fe.jpg" />. The searching machine first step is to correlate between the observer state <img src="4-7501290\e96c3b47-01ed-4134-a766-942b23b034f7.jpg" /> with the processor unsorted state <img src="4-7501290\fedf104a-838d-4ca6-9429-0b1830509e64.jpg" /> yielding:</p><disp-formula id="scirp.36564-formula100055"><label>(8)</label><graphic position="anchor" xlink:href="4-7501290\d4f8147b-a083-4b67-8bd5-013f5c9ae07d.jpg"  xlink:type="simple"/></disp-formula><p>with <img src="4-7501290\b67f819d-7804-457d-b02e-5b62756a31e8.jpg" /> being the unsorted state of Equation (7).</p><p>Assuming that the machine processor is fed with the observer selection. In response the machine processor exhibit the register state of Equation (7) in the associated representation:</p><disp-formula id="scirp.36564-formula100056"><label>(9)</label><graphic position="anchor" xlink:href="4-7501290\4cec98d1-6275-4138-8d61-8d8f3ff20c92.jpg"  xlink:type="simple"/></disp-formula><p>We refer this representation as the k-basis-representation. The question we address is how does the observer <img src="4-7501290\b9193e8d-55ed-45b2-97d7-7deb6a7ef689.jpg" />-selection can be followed by the r-space such that the unsorted state <img src="4-7501290\1e96e40c-a9ae-4739-8bd9-a1397dd1ec4c.jpg" /> will be represented by the <img src="4-7501290\7e335c87-ce6b-4324-b7e2-57e5a4b9379c.jpg" />- basis?</p><p>Suppose that <img src="4-7501290\971fe4a4-47f6-48b9-bfbd-142cd64679ff.jpg" /> is the operator that operates within the <img src="4-7501290\3833c213-3440-46c2-9d4b-d94e30a40b74.jpg" />-space and can be coupled to any observer selection<img src="4-7501290\7bec2a06-1ca7-4c6b-87ac-4a491001ace2.jpg" />. Clearly there are <img src="4-7501290\02a0e23e-28f8-4ba4-b4e2-6ffee940ef53.jpg" /> operators of the kind. The global processor task is to associate each operator with its compatible <img src="4-7501290\bb2cde9a-d1ea-4f05-ad4e-b07d65c277fd.jpg" />-state. This operation is activated by the following <img src="4-7501290\d27a6380-dc17-48a6-8281-f1092abfa3eb.jpg" />-operator:</p><disp-formula id="scirp.36564-formula100057"><label>(10)</label><graphic position="anchor" xlink:href="4-7501290\94d9afc3-0f1f-43b5-8861-3522cc6929ac.jpg"  xlink:type="simple"/></disp-formula><p>Once the observer select his query, say, the state <img src="4-7501290\83e5676c-e08e-44e7-a415-bff6cf47c043.jpg" /> and after the states are correlated as shown in Equation (8), the processor operation provides us with the output:</p><disp-formula id="scirp.36564-formula100058"><label>(11)</label><graphic position="anchor" xlink:href="4-7501290\a437543b-0d15-44c3-8ddd-0ce7555ed936.jpg"  xlink:type="simple"/></disp-formula><p>meaning that among all other possibilities the r-processor is now operating within the <img src="4-7501290\21683993-ad10-4594-a0c1-91b052153e1d.jpg" />-representation only. We note that <img src="4-7501290\64144ab7-bc33-4a09-94fe-47279202d4b6.jpg" /> can be regarded as an “eigenoperator” [13,14].</p></sec><sec id="s3_2"><title>3.2. The <img src="4-7501290\1dd72727-a392-471c-ae1e-213f253298ed.jpg" /> Operator</title><p>A simple measurement of the record k can be represented with the following projective operator:</p><disp-formula id="scirp.36564-formula100059"><label>(12)</label><graphic position="anchor" xlink:href="4-7501290\9a1e4445-8e18-4728-8d54-f0249c34f3b4.jpg"  xlink:type="simple"/></disp-formula><p>Applying the operator <img src="4-7501290\3d1a7be2-d4f8-46cc-bd08-e0558ae6e63b.jpg" /> on the unsorted state <img src="4-7501290\ce0ae9bc-4023-4e85-9837-f6208febba34.jpg" /> (see Equation (9)) and considering this operation by means of conducting a macroscopic measurement, we will probably obtain a <img src="4-7501290\232c0d84-8799-474c-990a-7ce827743220.jpg" /> output and consequently the remaining state will be the <img src="4-7501290\ac13a56b-79e1-4c7e-9392-7944622db536.jpg" />-state. Therefore in order to improve the odds of detecting the required <img src="4-7501290\2732ac70-1d6c-4b14-a781-b87d1c35b8e6.jpg" /> associated data, we apply the Pauli gate that switches between the <img src="4-7501290\bdab9acf-3893-4116-83f9-5ff1df0842b4.jpg" /> <img src="4-7501290\94ff2445-7336-4d20-8fc0-a6e2febf58d0.jpg" />-states while leaving the “eigensymbols” unchanged.</p><p>This improved operator is:</p><disp-formula id="scirp.36564-formula100060"><label>(13)</label><graphic position="anchor" xlink:href="4-7501290\7bfffe98-b36c-4432-982f-67f07197b75d.jpg"  xlink:type="simple"/></disp-formula><p>where the Pauli gate is</p><disp-formula id="scirp.36564-formula100061"><label>(14)</label><graphic position="anchor" xlink:href="4-7501290\8829e8b7-3bb2-499a-969f-416432063ac0.jpg"  xlink:type="simple"/></disp-formula><p>This yields:</p><disp-formula id="scirp.36564-formula100062"><label>(15)</label><graphic position="anchor" xlink:href="4-7501290\22c7e4f1-8346-4c97-8408-1c551a38e514.jpg"  xlink:type="simple"/></disp-formula><p>This eigenstates switching causes the high probability state <img src="4-7501290\cf7218e7-09d7-435a-b5d2-bc75c7ecf111.jpg" /> to possess the required eigensymbol data</p><p><img src="4-7501290\f6818779-b68f-48df-a023-54f8e92e8ff6.jpg" />with the high probability<img src="4-7501290\e37be8b1-d7cb-4eec-836c-26c8bac82ce3.jpg" />. Thusnot only we defined a pure searching algorithm by defining the observer query separately from the search engine, we also introduced a very rapid algorithm which composed mainly of two steps: The Pauli gate and a macroscopic measurement.</p></sec></sec><sec id="s4"><title>4. Summary</title><p>We summarize this paper with the following flowchart that shows our proposed algorithm:</p><p><img src="4-7501290\81d787e9-8ad2-4282-9343-71b680e0018e.jpg" /></p></sec><sec id="s5"><title>REFERENCES</title></sec></body><back><ref-list><title>References</title><ref id="scirp.36564-ref1"><label>1</label><mixed-citation publication-type="other" xlink:type="simple">A. Y. Vlasov, Quantum Physics, 1996, 9703010v1.</mixed-citation></ref><ref id="scirp.36564-ref2"><label>2</label><mixed-citation publication-type="other" xlink:type="simple">D. Deutsch, Proceedings of the Royal Society London: A, Vol. 400, 1985, pp. 97-117. doi:10.1098/rspa.1985.0070</mixed-citation></ref><ref id="scirp.36564-ref3"><label>3</label><mixed-citation publication-type="other" xlink:type="simple">R. Jozsa and N. Linden, Proceedings of the Royal Society London: A, Vol. 459, 2003, pp. 2011-2032.  
doi:10.1098/rspa.2002.1097</mixed-citation></ref><ref id="scirp.36564-ref4"><label>4</label><mixed-citation publication-type="other" xlink:type="simple">P. W. Shor, SIAM Journal on Computing, Vol. 26, 1997, pp. 1484-1509. doi:10.1137/S0097539795293172</mixed-citation></ref><ref id="scirp.36564-ref5"><label>5</label><mixed-citation publication-type="other" xlink:type="simple">M. A. Nielsen and I. L. Chuang, “Quantum Computation and Quantum Information,” Cambridge University Press, Cambridge, 2000.</mixed-citation></ref><ref id="scirp.36564-ref6"><label>6</label><mixed-citation publication-type="other" xlink:type="simple">L. Grover, Proceedings of 28th Annual ACM Symposium on the Theory of Computing, ACM Press, New York, 1996, p. 212.</mixed-citation></ref><ref id="scirp.36564-ref7"><label>7</label><mixed-citation publication-type="other" xlink:type="simple">D. Deutsch, Proceedings of the Royal Society London: A Vol. 425, 1989, p. 73.</mixed-citation></ref><ref id="scirp.36564-ref8"><label>8</label><mixed-citation publication-type="other" xlink:type="simple">C. A. Trugenberger, Quantum Physics, 2006, 0210176v2.</mixed-citation></ref><ref id="scirp.36564-ref9"><label>9</label><mixed-citation publication-type="other" xlink:type="simple">C. A. Trugenberger, Physical Review Letters, Vol. 87, 2001, Article ID: 067801   
doi:10.1137/S0097539795293172</mixed-citation></ref><ref id="scirp.36564-ref10"><label>10</label><mixed-citation publication-type="other" xlink:type="simple">C. A. Trugenberger, Physical Review Letters, Vol. 89, 2002, Article ID: 0277903.  
doi:10.1103/PhysRevLett.89.277903</mixed-citation></ref><ref id="scirp.36564-ref11"><label>11</label><mixed-citation publication-type="other" xlink:type="simple">D. F. Floess, E. Andersson and M. Hillery, 2010.  
arxiv.org/pdf/1006.1423</mixed-citation></ref><ref id="scirp.36564-ref12"><label>12</label><mixed-citation publication-type="other" xlink:type="simple">R. R. Tucci, 2010. http://qbnets.wordpress.com</mixed-citation></ref><ref id="scirp.36564-ref13"><label>13</label><mixed-citation publication-type="other" xlink:type="simple">Y. Roth, Europhysics Letters, Vol. 82, 2008, Article ID: 10006.</mixed-citation></ref><ref id="scirp.36564-ref14"><label>14</label><mixed-citation publication-type="other" xlink:type="simple">Y. Roth, International Journal of Theoretical Physics, Vol. 51, 2012, pp. 3847-3855.</mixed-citation></ref></ref-list></back></article>