首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A key feature of quantum information science is the understanding that groups of two or more quantum objects can have sta
A key feature of quantum information science is the understanding that groups of two or more quantum objects can have sta
admin
2011-01-17
125
问题
A key feature of quantum information science is the understanding that
groups of two or more quantum objects can have states that are entangled, such
that the members of an entangled collection of objects do not have their own
Line individual quantum states, only the group as a whole. Although one can use the
(5) mathematics of quantum theory to reason about entanglement, there is a great
danger that the classical basis of our analogies will mislead us. Despite its
strangeness, for a long time entanglement was regarded as a curiosity and was
mostly ignored by physicists and this changed when Bell predicted and
confirmed that entangled quantum systems exhibit behavior that is impossible in
(10) a classical world-impossible even if one could change the laws of physics to try
to emulate the quantum predictions within a classical framework of any sort.
The idea that entanglement falls wholly outside the scope of classical physics
prompted researchers to ask whether entanglement might be useful as a
resource for solving information-processing problems in new ways.
(15) Entanglement measures improve how researchers can analyze tasks such as
quantum teleportation and algorithms on quantum-mechanical computers.
Classical computation and communications have a well-developed assortment of
error-correcting codes to protect information against the depredations of noise,
an example being the repetition code. This scheme represents the bit 0 as a
(20) string of three bits, 000, and the bit 1 as a string of three bits, 111. If the
noise is relatively weak, it may sometimes flip one of the bits in a triplet,
changing, for instance, 000 to 010, but it will flip two bits in a triplet far less
often. Whenever we encounter 010 (or 100 or 001), we can be almost certain
the correct value is 000, or 0.
(25) Initially it appeared to be impossible to develop codes for quantum error
correction because quantum mechanics forbids us from learning with certainty
the unknown state of a quantum object-the obstacle, again, of trying to
extract more than one bit from a quantum bit. One cannot examine each copy of
a quantum bit and see that one copy must be discarded without altering each and
(30) every copy in the process, and making the copies in the first place is nontrivial:
quantum mechanics forbids taking an unknown quantum bit and reliably making
a duplicate, a result known as the no-cloning theorem. Clever ideas developed
independently by Shor showed quantum error correction can be performed
without ever learning the states of the quantum bits or needing to clone them.
(35) As with the triplet code, each value is represented by a set of quantum bits and
it is as if one ran the triplet 010 through a circuit that could spot that the middle
bit was different and flip it "sight unseen".
The passage implies that all of the following true is true concerning classical means of error correction EXCEPT
选项
A、The string 1110 should be interpreted to represent 1
B、The string 2020 should be interpreted to indicate the presence of noise
C、A four digit code is more likely to be accurate than a three digit code
D、It is permissible to duplicate the bits in a code
E、Three digits in agreement, such as 111, indicate the absence of degradation
答案
E
解析
转载请注明原文地址:https://www.kaotiyun.com/show/RxjO777K
本试题收录于:
GRE VERBAL题库GRE分类
0
GRE VERBAL
GRE
相关试题推荐
DuringatriptoobservewildanimalsinAfrica,Iencounteredtheleastbraveanimalonearth,thewildebeest(角马).Isatona
ThoughConfuciushaslonggone,hispowerideaundoubtedly______Chinesesocietyandtradition.
Thereisnodoubtthatadults,andevenhighlyeducatedadults,varygreatlyinthespeedandefficiencyoftheirreading.Some
Traditionally,universitieshavecarriedouttwomainactivities:researchandteaching.Manyexpertswouldarguethatboththes
TheannualcampaigntomakeSingapore’sthreemillionpeoplemorepoliteendedyesterdayandwasimmediatelyfollowedbyanothe
Thereisnodoubtthatadults,andevenhighlyeducatedadults,varygreatlyinthespeedandefficiencyoftheirreading.Some
Withouthearingawordofwhatisbeingsaidorshouted,anexperiencedtraderonthefloorofthestockexchangecanlistento
EachofQuestions1to7presentstwoquantities.QuantityAandQuantityB.Comparethetwoquantities.Youmayuseadditional
ADULATION:
RECANT:
随机试题
回收站是___________中的区域。
检查发现患者胸廓的前后径等于横径,并伴有肋间隙增宽者,应考虑为
A.IDLB.CMC.VLDLD.LDLE.HDLVLDL向LDL转化过程中的中间产物是
女,51岁,月经一年未来潮,每日数次出现烘热,出汗,面部发红,情绪烦躁,易怒,睡眠不好,时有心悸,血压时有波动。最可能诊断是
在感染过程的5种表现中,所占比例最低,但最易识别的是
A、酸值B、酯值C、pH值D、皂化值E、折光率代表挥发油中游离羧酸、酚类和结合态酯总量的指标是()
某工程采用单轴固结仪法测定土样的固结系数,测试数据如下:根据表中数据完成下列问题:对应下列选项中的()荷载作用下的固结系数计算有误。
下列选项中,()以企业经营的全部产品或业务的组合为研究对象,分析企业相关经营业务之间的现金流量的平衡问题,寻求资源的最佳组合。
甲厂是一家酿酒企业,注册类型为个人独资,法人代表杨某,经营范围:黄酒、米酒、配制酒生产、销售。企业的生产工艺为浸米、蒸饭、发酵、二次发酵、榨酒、过滤、兑制、杀菌、灌装、成品(黄酒),共有员工47名,从2012年9月开始一直从事黄酒和露酒生产。该企业的储酒
______isNOTanovelbytheBrontesisters.
最新回复
(
0
)