资源描述：
《量子通信中的预纠缠、信息压缩和保密问题》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。
1、Priorentanglement,messagecompressionandprivacyinquantumcommunicationRahulJain∗JaikumarRadhakrishnanPranabSenU.C.BerkeleyTataInstituteofFundamentalUniversityofWaterlooBerkeley,USA.Research,Mumbai,IndiaWaterloo,Canada.rahulj@eecs.berkeley.eduandp2sen@iqc.caToyotaTechnologicalInsti
2、tuteChicago,USA.jaikumar@tti-c.orgAbstractconstantfactor.Consideratwo-partyquantumcommunicationprotocolforcomputingsomefunctionf:{0,1}n×{0,1}n→Z.1IntroductionWeshowthatthefirstmessageofPcanbecompressedtoO(k)classicalbitsusingpriorentanglementifitcarriesatConsideratwo-partyquantum
3、communicationprotocolmostkbitsofinformationaboutthesender’sinput.Thisim-nnPforcomputingsomefunctionf:{0,1}×{0,1}→Z.pliesageneraldirectsumresultforone-roundandsimulta-WeassumethatPusesonlyunitarytransformationsforitsneousquantumprotocols.Italsoimpliesanewroundelim-internalcomputa
4、tion,exceptattheveryendwhenthefinalinationlemmainquantumcommunication,whichallowsusrecipientofamessagemakesavonNeumannmeasurementtoextendrecentclassicallowerboundsonthecellprobeofsomeofherqubitstodeclaretheoutput.Thus,thejointcomplexityofsomedatastructureproblems,e.g.approx-state
5、ofAliceandBobisalwayspureduringtheexecutionimatenearestneighborsearchingontheHammingcubenofP.Wealsoassumethattheplayersmakesafecopiesof{0,1},tothequantumsetting.WethenshowanoptimaltheirrespectiveinputsusingCNOTgatesbeforecommenc-tradeoffbetweentheprivacylossesofAliceandBobincom-
6、ingtheprotocol.Thesesafecopiesoftheinputsarenotputingfintermsoftheone-roundquantumcommunicationaffectedbythesubsequentoperationsofP,andarenevercomplexityoffwithpriorentanglement.Thistradeoffissentasmessages.Inthispaper,weconsiderprotocolswithindependentofthenumberofroundsofcommu
7、nication.andwithoutpriorentanglement.Bypriorentanglement,weTheabovemessagecompressionandprivacytradeoffre-meanapurequantumstate
8、φthatissharedbetweenAlicesultsusealotofqubitsofpriorentanglement,leadingoneandBobandthatisindependentoftheirinput(x,y).
9、φtowonderhowmuchpriorentangle
10、mentisreallyrequiredcanbesupportedonanextremely
