Quaternionic Computing

发布时间:2021-06-08

Quaternionic Computing

QuaternionicComputing

Jos´eM.Fernandez,WilliamA.Schneeberger

arXiv:quant-ph/0307017v2 5 Nov 2004February1,2008AbstractWeintroduceamodelofcomputationbasedonquaternions,whichisinspiredonthequantumcomputingmodel.Purestatesarevectorsofasuitablelinearspaceoverthequaternions.Otheraspectsofthetheoryarethesameasinquantumcomputing:super-positionandlinearityofthestatespace,unitarityofthetransformations,andprojectivemeasurements.However,onenotableexceptionisthefactthatquaternioniccircuitsdonothaveauniquelyde nedbehaviour,unlessatotalorderingofevaluationofthegatesisde ned.Givensuchanorderingauniqueunitaryoperatorcanbeassociatedwiththequaternioniccircuitandapropersemanticsofcomputationcanbeassociatedwithit.Themainresultofthispaperconsistsinshowingthatthismodelisnomorepowerfulthanquantumcomputing,aslongassuchanorderingofgatescanbede ned.Moreconcretelyweshow,thatforallquaternioniccomputationusingnquaterbits,thebehaviourofthecircuitforeachpossiblegateorderingcanbesimulatedwithn+1qubits,andthiswithlittleornooverheadincircuitsize.Theproofofthisresultisinspiredofanewsimpli edandimprovedproofoftheequivalenceofasimilarmodelbasedonrealamplitudestoquantumcomputing,whichstatesthatanyquantumcomputationusingnqubitscanbesimulatedwithn+1rebits,andinthiswithnocircuitsizeoverhead.Beyondthispotentialcomputationalequivalence,however,weproposethismodelasasimplerframeworkinwhichtodiscussthepossibilityofaquaternionicquantummechanicsorinformationtheory.Inparticular,italreadyallowsustoillustratethattheintroduction

ofquaternionsmightviolatesomeofthe“natural”propertiesthatwehavecometoexpectfromphysicalmodels.

1Introduction

QuantumComputingrepresentsyetanotherdisconcertingpuzzletoComplexityTheory.Whatweknowtodayisthatquantumcomputingdevicescane cientlysolvecertainproblems,which,inappearance,classicalorprobabilisticcomputerscannotsolvee ciently.EventhoughwewouldliketobelievethatquantumcomputingviolatesthestrongChurch-Turingthesis,thesoretruthisthattheknownresultsdonotprovideusaproof,onlyconstituting,atbest,“strongevidence”thereof.

Yet,eventhoughwecannotprovideastrictseparationbetweenthesemodels,wedoknowcertaininclusionsbetweenvariationsofthesecomputingmodels.Perhapsthemostnatural

Quaternionic Computing.doc 将本文的Word文档下载到电脑

精彩图片

热门精选

大家正在看

× 游客快捷下载通道(下载后可以自由复制和排版)

限时特价:7 元/份 原价:20元

支付方式:

开通VIP包月会员 特价:29元/月

注:下载文档有可能“只有目录或者内容不全”等情况,请下载之前注意辨别,如果您已付费且无法下载或内容有问题,请联系我们协助你处理。
微信:fanwen365 QQ:370150219