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Quantum channel

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4372:, a sender wishes to transmit an arbitrary quantum state of a particle to a possibly distant receiver. Consequently, the teleportation process is a quantum channel. The apparatus for the process itself requires a quantum channel for the transmission of one particle of an entangled-state to the receiver. Teleportation occurs by a joint measurement of the sent particle and the remaining entangled particle. This measurement results in classical information which must be sent to the receiver to complete the teleportation. Importantly, the classical information can be sent after the quantum channel has ceased to exist. 7972: 6834: 8779: 7962: 9081: 6590: 1018:
So far we have only defined quantum channel that transmits only quantum information. As stated in the introduction, the input and output of a channel can include classical information as well. To describe this, the formulation given so far needs to be generalized somewhat. A purely quantum channel,
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can be viewed as representing a message consisting of possibly infinite number of words. The limit supremum condition in the definition says that, in the limit, faithful transmission can be achieved by invoking the channel no more than
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of the state is maintained during transmission through the channel. Contrast this with the transmission of electrical pulses through wires (a classical channel), where only classical information (e.g. 0s and 1s) can be sent.
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of a system but as a pipeline intended to carry quantum information. (Some authors use the term "quantum operation" to include trace-decreasing maps while reserving "quantum channel" for strictly trace-preserving maps)
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The observable map, in the Schrödinger picture, has a purely classical output algebra and therefore only describes measurement statistics. To take the state change into account as well, we define what is called a
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is sometimes given as the generalized mathematical framework for conveying both quantum and classical information. In axiomatizations of quantum mechanics, the classical information is carried in a
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Classical information can then be included in this formulation. The observables of a classical system can be assumed to be a commutative C*-algebra, i.e. the space of continuous functions
2751: 1954: 1829: 6686: 5489: 3233: 6819: 6332: 6236: 6201: 5816: 4800: 4360:. The time evolution is one example of a pure channel. This terminology again comes from the channel-state duality. A channel is pure if and only if its dual state is a pure state. 2644: 6060: 4832: 4496: 2008: 1726: 2977: 1441: 1777: 426: 468: 6585:{\displaystyle C(\mathbb {C} ^{m},\mathbb {C} ^{n})=C(\mathbb {C} ^{m\times m},\mathbb {C} ^{n\times n})=C(\mathbb {C} ^{m\times m},\mathbb {C} ^{n})={\frac {\log n}{\log m}}.} 3291: 1669: 6718: 6297: 6265: 6154: 2743: 1275: 5949: 3170: 6987:
Weedbrook, Christian; Pirandola, Stefano; GarcĂ­a-PatrĂłn, RaĂșl; Cerf, Nicolas J.; Ralph, Timothy C.; Shapiro, Jeffrey H.; Lloyd, Seth (2012). "Gaussian quantum information".
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The partial trace operation is a CPTP map, therefore a quantum channel in the Schrödinger picture. In the Heisenberg picture, the dual map of this channel is
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The above says, for instance, an ideal quantum channel is no more efficient at transmitting classical information than an ideal classical channel. When
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be a chosen ideal channel. To make the comparison possible, one needs to encode and decode Ί via appropriate devices, i.e. we consider the composition
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John A. Holbrook, David W. Kribs, and Raymond Laflamme. "Noiseless Subsystems and the Structure of the Commutant in Quantum Error Correction."
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between the density matrices is specified, a standard linearity argument, together with the finite-dimensional assumption, allow us to extend
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is the time. Clearly this gives a CPTP map in the Schrödinger picture and is therefore a channel. The dual map in the Heisenberg picture is
378: 4949: 7853: 5652: 5745: 7754: 7415: 4388:. Single photons can be transmitted up to 100 km in standard fiber optics before losses dominate. The photon's time-of-arrival ( 8747: 1010:. Physically speaking, this means that, in the Heisenberg picture, the trivial observable remains trivial after applying the channel. 6340: 4860: 1310: 1103: 8058: 7316: 3753:{\displaystyle \Phi _{2}\left({\begin{bmatrix}\rho (F_{1})\\\vdots \\\rho (F_{n})\end{bmatrix}}\right)=\sum _{i}\rho (F_{i})R_{i}.} 8759: 7641: 3892: 8443: 8001: 1864: 6405:
This is equivalent to the no-teleportation theorem: it is impossible to transmit quantum information via a classical channel.
8377: 4208: 2460:{\displaystyle \Psi (\rho )={\begin{bmatrix}\langle F_{1},\rho \rangle \\\vdots \\\langle F_{n},\rho \rangle \end{bmatrix}},} 74:
We will assume for the moment that all state spaces of the systems considered, classical or quantum, are finite-dimensional.
3958: 8300: 7965: 7151: 9107: 8808: 7923: 6733: 1025: 686: 7499: 8031: 7994: 7975: 7863: 7116: 2867:{\displaystyle \Phi (\rho )={\begin{bmatrix}\rho (F_{1})\cdot F_{1}\\\vdots \\\rho (F_{n})\cdot F_{n}\end{bmatrix}}.} 2234: 1578: 5712: 8141: 7791: 7449: 2471: 1917: 1785: 8714: 8423: 8418: 8126: 7786: 7514: 7494: 1676: 6644: 5908:{\displaystyle \lim _{\alpha }\Delta ({\hat {\Psi }}^{\otimes m_{\alpha }},\Psi _{id}^{\otimes n_{\alpha }})=0.} 5455: 3175: 8801: 8726: 8398: 7781: 1280:
Therefore, in the Heisenberg picture, if the classical information is part of, say, the input, we would define
85:: the output of a channel at a given time depends only upon the corresponding input and not any previous ones. 7293: 6789: 6302: 6206: 6171: 9085: 8704: 8481: 8403: 8275: 8171: 8041: 7814: 7636: 7539: 7200: 6267:
will have an ideal channel denoted by the same symbol. We can now state some fundamental channel capacities.
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prepares his (quantum) system in a specific state. In the Schrödinger picture, the first part of the channel
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is only required to be not trace-increasing. In this article, it will be assumed that all channels are CPTP.
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between channels. Since a channel can be viewed as a linear operator, it is tempting to use the natural
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where the inner product is the Hilbert–Schmidt inner product. Furthermore, viewing states as normalized
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It is relevant to note here that both of the above bounds on capacities can be broken, with the aid of
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be the effects (POVM) associated to an observable. In the Schrödinger picture, an instrument is a map
1543:. Positivity of a map is defined accordingly. This characterization is not universally accepted; the 1251: 8892: 8877: 8566: 8433: 8357: 8318: 8255: 8234: 8191: 8084: 7524: 7489: 7385: 7328: 6962: 5921: 3564:{\displaystyle \;\Phi _{1}(\rho )={\begin{bmatrix}\rho (F_{1})\\\vdots \\\rho (F_{n})\end{bmatrix}}.} 3130: 57:(CP) trace-preserving maps between spaces of operators. In other words, a quantum channel is just a 6076: 1466: 1283: 971: 42:, as well as classical information. An example of quantum information is the general dynamics of a 9035: 9030: 8959: 8934: 8919: 8914: 8909: 8633: 8613: 8603: 8593: 8549: 8109: 7697: 7670: 7646: 7609: 7400: 7333: 7268: 7253: 7223: 7146: 6957: 6691:
that is, it is the capacity of Κ with respect to the ideal channel on the classical one-bit system
5141:{\displaystyle {\hat {\Psi }}=D\circ \Phi \circ E:{\mathcal {B}}_{2}\rightarrow {\mathcal {A}}_{2}} 4041: 2669: 6883: 4040:
A measure-and-prepare channel can not be the identity map. This is precisely the statement of the
2070: 8328: 8239: 7848: 7582: 7474: 7444: 7243: 8742: 8290: 6916: 6100: 5988: 5616: 5417: 5284:{\displaystyle \Delta ({\hat {\Psi }},\Psi _{id})=\inf _{E,D}\|{\hat {\Psi }}-\Psi _{id}\|_{cb}} 4431: 4403: 9052: 8974: 8653: 8428: 8408: 8333: 8186: 7918: 7682: 7675: 7422: 6626:. These results indicate the significant role played by entanglement in quantum communication. 4333: 3103: 2574:{\displaystyle \Psi (\rho )={\begin{bmatrix}\rho (F_{1})\\\vdots \\\rho (F_{n})\end{bmatrix}}.} 2334: 940: 882: 602: 8229: 5393: 4615: 4567: 4547: 1490: 225: 161: 9025: 8999: 8824: 8678: 8176: 8156: 7838: 7464: 7390: 7355: 6615: 4369: 4052: 4045: 354: 197: 8964: 8887: 8709: 8638: 8583: 8313: 8121: 8079: 7628: 7377: 7228: 7074: 7006: 6611: 5968: 5596: 4837: 4740: 4595: 4585: 4527: 4397: 4393: 4339: 4315: 4185: 4090: 4070: 3592: 3436: 3238: 2649: 2311: 2120: 2043: 2016: 920: 854: 750: 629: 582: 562: 516: 484: 360: 336: 313: 282: 255: 231: 130: 103: 4336:, who introduced them). The minimum number of Kraus operators is called the Kraus rank of 1218: 1149: 437:
is the identity map on the ancilla, must also be positive. Therefore, it is required that
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From the definition, it is vacuously true that 0 is an achievable rate for any channel.
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is the number of letters per invocation of the channel that can be sent without error.
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Consider quantum channels that transmit only quantum information. This is precisely a
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in the Heisenberg picture. With the assumption that everything is finite-dimensional,
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performs the measurement of an observable and communicates the measurement outcome to
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to include the relevant classical observables. An example of this would be a channel
94: 58: 6203:. As a slight abuse of notation, this ideal quantum channel will be also denoted by 8899: 8491: 8486: 8343: 8224: 7594: 7544: 7321: 7094: 7082: 7014: 5380:{\displaystyle \Psi _{id}^{\otimes n}=\Psi _{id}\otimes \cdots \otimes \Psi _{id}.} 4940: 4727:{\displaystyle \|\Phi -\Lambda \|=\sup\{\|(\Phi -\Lambda )(A)\|\;|\;\|A\|\leq 1\}.} 4168:{\displaystyle \Psi :\mathbb {C} ^{n\times n}\rightarrow \mathbb {C} ^{m\times m}.} 3883: 62: 6160:
dimensional quantum system, the ideal channel is the identity map on the space of
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is therefore a measure of the ability of the channel to transmit words of length
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Before giving the definition of channel capacity, the preliminary notion of the
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of a channel needs to be discussed. When considering the capacity of a channel
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Another measure of how well a quantum channel preserves information is called
3395:{\displaystyle {\tilde {\Psi }}(A)=\sum _{i}\Psi _{i}(A)=\sum _{i}M_{i}AM_{i}} 2961:{\displaystyle f={\begin{bmatrix}f_{1}\\\vdots \\f_{n}\end{bmatrix}}\in C(X).} 2067:'s are assumed to be positive operators acting on appropriate state space and 9101: 9040: 8939: 8618: 8471: 8362: 8265: 8181: 8151: 8104: 7651: 7469: 7395: 5445: 5167:
are unital CP maps with appropriate domains. The quantity of interest is the
4589: 4055:, a channel is measure-and-prepare if and only if the corresponding state is 2218:{\displaystyle f={\begin{bmatrix}f_{1}\\\vdots \\f_{n}\end{bmatrix}}\in C(X)} 1847: 155: 9020: 8501: 8099: 8094: 7871: 7796: 5057:{\displaystyle \Psi _{id}:{\mathcal {B}}_{2}\rightarrow {\mathcal {A}}_{2}} 2308:
to obtain the quantum mechanical observable. It can be easily checked that
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To make the operator norm even a more undesirable candidate, the quantity
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in the Heisenberg picture, is a linear map Κ between spaces of operators:
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are used as a basis to encode quantum information for purposes such as
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uniquely to the full space of operators. This leads to the adjoint map
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allows one to transmit quantum information using a classical channel.
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with the infimum being taken over all possible encoders and decoders.
4993:{\displaystyle \Psi :{\mathcal {B}}_{1}\rightarrow {\mathcal {A}}_{1}} 4400:. The channel is capable of transmitting not only basis states (e.g. 8393: 8074: 7725: 3172:(this can always be done since elements of a POVM are positive) then 7986: 7910: 7886: 7745: 7710: 6986: 5702:{\displaystyle \{n_{\alpha }\},\{m_{\alpha }\}\subset \mathbb {N} } 47: 7069: 7001: 5802:{\displaystyle \lim \sup _{\alpha }(n_{\alpha }/m_{\alpha })<r} 7937: 7554: 1568:
For a purely quantum system, the time evolution, at certain time
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Experimentally, a simple implementation of a quantum channel is
7914: 7410: 6395:{\displaystyle C(\mathbb {C} ^{m},\mathbb {C} ^{n\times n})=0.} 4924:{\displaystyle \|\Phi \|_{cb}=\sup _{n}\|\Phi \otimes I_{n}\|.} 4385: 1382:{\displaystyle \Psi :L(H_{B})\otimes C(X)\rightarrow L(H_{A}).} 1136:{\displaystyle \Psi :{\mathcal {B}}\rightarrow {\mathcal {A}}.} 4044:, which says classical teleportation (not to be confused with 81:
in the section title carries the same meaning as in classical
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The mathematical model of a channel used here is same as the
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independently and is the quantum mechanical counterpart of
2111: 1093:). The operator spaces can be viewed as finite-dimensional 3945:{\displaystyle \Phi ^{*}=\Phi _{1}^{*}\circ \Phi _{2}^{*}} 7549: 7534: 1901:{\displaystyle \rho ^{A}=\operatorname {Tr} _{B}\;\rho .} 6634:
Using the same notation as the previous subsection, the
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where the reference system is now the one qubit system
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As stated before, for a system with observable algebra
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However, the operator norm may increase when we tensor
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as a map between Hilbert spaces, we obtain its adjoint
7055:, Lecture Notes in Physics Volume 611, Springer, 2002. 4030:{\displaystyle \;\Phi ^{*}(A)=\sum _{i}R_{i}(A)F_{i}.} 3641: 3612:
takes the above classical state to the density matrix
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to be the identity map. Such a comparison requires a
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making a measurement, i.e. it is the observable map:
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Consider a composite quantum system with state space
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A bistochastic quantum channel is a quantum channel
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The channel capacity of the classical ideal channel
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only constitute a proper subset of the operators on
7376: 3429:classically. According to the message he receives, 481:Density matrices are specified to have trace 1, so 27:
Foundational object in quantum communication theory
6940: 6901: 6813: 6776:{\displaystyle C(\Psi ,\mathbb {C} ^{2\times 2}),} 6775: 6712: 6680: 6584: 6394: 6326: 6291: 6259: 6230: 6195: 6148: 6119: 6089: 6054: 6007: 5977: 5956:times the length of a word. One can also say that 5943: 5907: 5801: 5734: 5701: 5635: 5605: 5561: 5483: 5436: 5402: 5379: 5283: 5140: 5056: 4992: 4923: 4846: 4826: 4794: 4749: 4726: 4624: 4604: 4576: 4556: 4536: 4490: 4448: 4420: 4348: 4324: 4278: 4194: 4167: 4099: 4079: 4029: 3944: 3867: 3752: 3601: 3563: 3445: 3394: 3285: 3247: 3227: 3164: 3119: 3089: 2960: 2866: 2737: 2693: 2658: 2638: 2573: 2459: 2350: 2320: 2289: 2217: 2129: 2102: 2059: 2032: 2002: 1948: 1900: 1823: 1771: 1720: 1663: 1610: 1535: 1515: 1479: 1455: 1435: 1381: 1296: 1269: 1236: 1207: 1187: 1167: 1135: 1079:{\displaystyle \Psi :L(H_{B})\rightarrow L(H_{A})} 1078: 1002: 956: 929: 898: 863: 840: 759: 740:{\displaystyle \Phi :L(H_{A})\rightarrow L(H_{B})} 739: 638: 618: 591: 571: 525: 493: 462: 420: 369: 345: 322: 298: 271: 240: 216: 186: 146: 119: 4934: 4834:The solution is to introduce, for any linear map 509:used to describe a map are sometimes abbreviated 9099: 5821: 5753: 5749: 5222: 4887: 4660: 4544:, we need to compare it with an "ideal channel" 2114:.) In the Heisenberg picture, the corresponding 310:As required by postulates of quantum mechanics, 7131: 6875: 2290:{\displaystyle \;\Psi (f)=\sum _{i}f_{i}F_{i}.} 1611:{\displaystyle \rho \rightarrow U\rho \;U^{*},} 392:is coupled to the system, then the induced map 5735:{\displaystyle m_{\alpha }\rightarrow \infty } 4375: 4107:is a unital CP map between spaces of matrices 4067:Consider the case of a purely quantum channel 3408: 38:is a communication channel which can transmit 8809: 8002: 7117: 3421:wish to communicate in the following manner: 69: 7043:. Volume 2, Number 5, p. 381-419. Oct 2003. 5938: 5925: 5688: 5675: 5669: 5656: 5269: 5237: 4915: 4896: 4871: 4864: 4789: 4770: 4718: 4709: 4703: 4693: 4666: 4663: 4654: 4642: 4485: 4471: 4443: 4415: 3293:gives precisely the observable map. The map 2633: 2601: 2443: 2424: 2410: 2391: 2358:takes density matrices to classical states: 1949:{\displaystyle A\rightarrow A\otimes I_{B},} 1824:{\displaystyle \rho \in H_{A}\otimes H_{B},} 832: 804: 798: 777: 5000:be a channel in the Heisenberg picture and 4511: 1975:An observable associates a numerical value 9080: 8816: 8802: 8009: 7995: 7124: 7110: 6681:{\displaystyle C(\Psi ,\mathbb {C} ^{2}),} 6616:entanglement-assisted teleportation scheme 6023: 5484:{\displaystyle {\hat {\Psi }}^{\otimes m}} 4702: 4696: 4180:Choi's theorem on completely positive maps 3962: 3470: 3228:{\displaystyle \;\Psi _{i}(A)=M_{i}AM_{i}} 3179: 2971:The dual map in the Heisenberg picture is 2238: 1891: 1594: 8823: 7068: 7000: 6795: 6751: 6700: 6662: 6537: 6516: 6486: 6465: 6441: 6426: 6408:Moreover, the following equalities hold: 6367: 6352: 6308: 6279: 6247: 6212: 6177: 6062:is the supremum of all achievable rates. 5695: 4146: 4125: 1996: 1257: 6980: 6814:{\displaystyle \mathbb {C} ^{2\times 2}} 6630:Classical and quantum channel capacities 6327:{\displaystyle \mathbb {C} ^{n\times n}} 6299:with respect to a quantum ideal channel 6231:{\displaystyle \mathbb {C} ^{n\times n}} 6196:{\displaystyle \mathbb {C} ^{n\times n}} 5583:This leads to the following definition: 4456:) but also superpositions of them (e.g. 4356:. A channel with Kraus rank 1 is called 3889:In the Heisenberg picture, the dual map 3127:is defined in the following way: Factor 1089:that is unital and completely positive ( 1013: 507:completely positive and trace preserving 154:be the state spaces (finite-dimensional 7642:Continuous-variable quantum information 5305:times, so we consider the tensor power 4757:with the identity map on some ancilla. 3763:The total operation is the composition 357:of positive elements. In other words, 194:will denote the family of operators on 53:Terminologically, quantum channels are 14: 9100: 4795:{\displaystyle \|\Phi \otimes I_{n}\|} 2639:{\displaystyle \{F_{1},\dots ,F_{n}\}} 88: 8797: 8016: 7990: 7105: 7058: 6068: 6055:{\displaystyle \;C(\Psi ,\Psi _{id})} 5301:, the ideal channel is to be applied 4827:{\displaystyle n\rightarrow \infty .} 4491:{\displaystyle |0\rangle +|1\rangle } 2003:{\displaystyle f_{i}\in \mathbb {C} } 1721:{\displaystyle A\rightarrow U^{*}AU.} 536: 333:Since density matrices are positive, 97:, whose properties we now summarize. 6828: 3405:describes the overall state change. 1436:{\displaystyle L(H_{B})\otimes C(X)} 228:, a purely quantum channel is a map 18:Completely positive trace-preserving 7053:How to Correct Small Quantum Errors 6824: 4592:. In other words, the closeness of 4506: 4046:entanglement-assisted teleportation 1772:{\displaystyle H_{A}\otimes H_{B}.} 937:is assumed to be trace preserving, 917:It can be directly checked that if 421:{\displaystyle I_{n}\otimes \Phi ,} 24: 6920: 6887: 6743: 6654: 6140: 6127:is by definition the identity map 6105: 6082: 6037: 6030: 5993: 5972: 5869: 5840: 5830: 5729: 5621: 5600: 5536: 5514: 5504: 5463: 5422: 5362: 5340: 5316: 5256: 5243: 5203: 5190: 5181: 5127: 5110: 5095: 5077: 5043: 5026: 5008: 4979: 4962: 4953: 4899: 4867: 4841: 4818: 4773: 4744: 4678: 4672: 4651: 4645: 4619: 4599: 4571: 4551: 4531: 4343: 4319: 4212: 4189: 4117: 4094: 4074: 3964: 3928: 3910: 3897: 3802: 3789: 3773: 3623: 3596: 3472: 3440: 3338: 3306: 3265: 3242: 3181: 3108: 3061: 3021: 2981: 2755: 2653: 2488: 2368: 2339: 2331:The corresponding Schrödinger map 2315: 2239: 2124: 1472: 1443:is still a C*-algebra. An element 1314: 1289: 1125: 1115: 1107: 1029: 976: 945: 924: 887: 858: 808: 786: 754: 690: 683:inner product. Therefore, viewing 633: 607: 586: 566: 520: 488: 463:{\displaystyle I_{n}\otimes \Phi } 457: 412: 364: 340: 317: 235: 25: 9119: 4854:between C*-algebras, the cb-norm 3878:Channels of this form are called 3589:, the second part of the channel 3286:{\displaystyle \Psi (f\otimes I)} 2110:. (Such a collection is called a 1664:{\displaystyle U=e^{-iHt/\hbar }} 1656: 1563: 9079: 8778: 8777: 7971: 7970: 7961: 7960: 6832: 6713:{\displaystyle \mathbb {C} ^{2}} 6292:{\displaystyle \mathbb {C} ^{m}} 6260:{\displaystyle \mathbb {C} ^{m}} 6149:{\displaystyle I_{\mathcal {B}}} 5414:inputs undergoing the operation 4363: 2738:{\displaystyle C(X)\otimes L(H)} 1277:with entry-wise multiplication. 1270:{\displaystyle \mathbb {R} ^{n}} 626:, which describes the action of 555:and same can be said for system 5944:{\displaystyle \{n_{\alpha }\}} 5159:is a decoder. In this context, 4062: 3165:{\displaystyle F_{i}=M_{i}^{2}} 306:with the following properties: 8727:Relativistic quantum mechanics 7063:, Cambridge University Press, 7041:Quantum Information Processing 7033: 6929: 6923: 6896: 6890: 6767: 6740: 6672: 6651: 6603:, the best one can achieve is 6547: 6511: 6502: 6460: 6451: 6421: 6383: 6347: 6090:{\displaystyle {\mathcal {B}}} 6049: 6027: 5896: 5843: 5833: 5790: 5762: 5726: 5556: 5517: 5507: 5466: 5246: 5215: 5193: 5184: 5121: 5080: 5037: 4973: 4935:Definition of channel capacity 4815: 4805:may increase without bound as 4698: 4690: 4684: 4681: 4669: 4478: 4464: 4436: 4408: 4221: 4215: 4141: 4011: 4005: 3979: 3973: 3849: 3836: 3817: 3811: 3782: 3776: 3734: 3721: 3690: 3677: 3660: 3647: 3547: 3534: 3517: 3504: 3487: 3481: 3353: 3347: 3321: 3315: 3309: 3280: 3268: 3196: 3190: 3076: 3070: 3036: 3030: 2996: 2984: 2952: 2946: 2837: 2824: 2794: 2781: 2764: 2758: 2732: 2726: 2717: 2711: 2688: 2682: 2557: 2544: 2527: 2514: 2497: 2491: 2377: 2371: 2248: 2242: 2228:to the quantum mechanical one 2212: 2206: 1924: 1731: 1696: 1585: 1480:{\displaystyle {\mathcal {A}}} 1430: 1424: 1415: 1402: 1373: 1360: 1354: 1351: 1345: 1336: 1323: 1297:{\displaystyle {\mathcal {B}}} 1231: 1225: 1162: 1156: 1120: 1073: 1060: 1054: 1051: 1038: 1003:{\displaystyle \Phi ^{*}(I)=I} 991: 985: 823: 817: 795: 789: 734: 721: 715: 712: 699: 679:) are Hilbert spaces with the 559:. However, once a linear map 388:of arbitrary finite dimension 181: 168: 13: 1: 8705:Quantum statistical mechanics 8482:Quantum differential calculus 8404:Delayed-choice quantum eraser 8172:Symmetry in quantum mechanics 7637:Adiabatic quantum computation 6973: 3582:prepares his system in state 2694:{\displaystyle \rho \in L(H)} 2584: 2103:{\textstyle \sum _{i}F_{i}=I} 1970: 1248:-dimensional Euclidean space 7688:Topological quantum computer 6968:Quantum depolarizing channel 6902:{\displaystyle \Phi (\rho )} 6876:Bistochastic quantum channel 5576:faithfully by being invoked 5450:m invocations of the channel 5297:To transmit words of length 4518:norm of complete boundedness 4332:(after the German physicist 2476:Riesz representation theorem 2137:maps a classical observable 1846:, is obtained by taking the 7: 8507:Quantum stochastic calculus 8497:Quantum measurement problem 8419:Mach–Zehnder interferometer 7966:Quantum information science 7133:Quantum information science 6951: 5587:A non-negative real number 4376:In the experimental setting 3409:Measure-and-prepare channel 1963:is an observable of system 1558: 1244:can be identified with the 906:maps observables on system 541:Density matrices acting on 10: 9124: 9108:Quantum information theory 9063:Thermoacoustic heat engine 7361:quantum gate teleportation 7061:Quantum Information Theory 7051:M. Keyl and R. F. Werner, 6941:{\displaystyle \Phi (I)=I} 6870:fidelity of quantum states 6120:{\displaystyle \Psi _{id}} 6008:{\displaystyle \Psi _{id}} 5636:{\displaystyle \Psi _{id}} 5437:{\displaystyle \Psi _{id}} 4449:{\displaystyle |1\rangle } 4421:{\displaystyle |0\rangle } 501:has to preserve the trace. 70:Memoryless quantum channel 32:quantum information theory 9075: 9048:Immersive virtual reality 9008: 8838: 8831: 8773: 8735: 8687: 8567:Quantum complexity theory 8545:Quantum cellular automata 8520: 8452: 8386: 8299: 8248: 8235:Path integral formulation 8202: 8067: 8024: 7956: 7899: 7862: 7828: 7805: 7772: 7763: 7696: 7625: 7563: 7523: 7490:Quantum Fourier transform 7435: 7386:Post-quantum cryptography 7329:Entanglement distillation 7302: 7211: 7139: 7087:10.1017/9781316809976.001 7019:10.1103/RevModPhys.84.621 6989:Reviews of Modern Physics 6963:Amplitude damping channel 3578:-th measurement outcome, 3120:{\displaystyle \Psi _{i}} 2351:{\displaystyle \Psi ^{*}} 957:{\displaystyle \Phi ^{*}} 899:{\displaystyle \Phi ^{*}} 619:{\displaystyle \Phi ^{*}} 61:viewed not merely as the 9031:Digital scent technology 8634:Quantum machine learning 8614:Quantum key distribution 8604:Quantum image processing 8594:Quantum error correction 8444:Wheeler's delayed choice 7976:Quantum mechanics topics 7671:Quantum machine learning 7647:One-way quantum computer 7500:Quantum phase estimation 7401:Quantum key distribution 7334:Monogamy of entanglement 6958:No-communication theorem 5403:{\displaystyle \otimes } 4625:{\displaystyle \Lambda } 4577:{\displaystyle \Lambda } 4557:{\displaystyle \Lambda } 4512:The cb-norm of a channel 4042:no teleportation theorem 3574:If, in the event of the 2666:with pure quantum input 2010:to a quantum mechanical 1516:{\displaystyle a=x^{*}x} 653:The spaces of operators 474:. Such maps are called 187:{\displaystyle L(H_{A})} 8550:Quantum finite automata 7583:Randomized benchmarking 7445:Amplitude amplification 7059:Wilde, Mark M. (2017), 9053:Magnetic refrigeration 8654:Quantum neural network 7683:Quantum Turing machine 7676:quantum neural network 7423:Quantum secret sharing 6942: 6903: 6815: 6777: 6714: 6682: 6586: 6396: 6328: 6293: 6261: 6232: 6197: 6150: 6121: 6091: 6056: 6009: 5979: 5945: 5909: 5803: 5736: 5703: 5637: 5607: 5563: 5485: 5438: 5404: 5381: 5285: 5142: 5058: 4994: 4925: 4848: 4828: 4796: 4751: 4728: 4626: 4606: 4578: 4558: 4538: 4492: 4450: 4422: 4350: 4326: 4280: 4247: 4196: 4169: 4101: 4081: 4031: 3946: 3869: 3754: 3603: 3565: 3447: 3396: 3287: 3249: 3229: 3166: 3121: 3091: 2962: 2868: 2739: 2701:and with output space 2695: 2660: 2640: 2575: 2461: 2352: 2322: 2291: 2219: 2131: 2104: 2061: 2034: 2004: 1950: 1902: 1825: 1773: 1722: 1665: 1612: 1537: 1517: 1487:is called positive if 1481: 1457: 1437: 1383: 1298: 1271: 1238: 1209: 1189: 1169: 1137: 1080: 1004: 958: 931: 900: 865: 842: 761: 741: 640: 620: 593: 573: 527: 495: 464: 422: 371: 347: 324: 300: 273: 242: 218: 217:{\displaystyle H_{A}.} 188: 148: 121: 9026:Cloak of invisibility 8825:Emerging technologies 8679:Quantum teleportation 8192:Wave–particle duality 7755:Entanglement-assisted 7716:quantum convolutional 7391:Quantum coin flipping 7356:Quantum teleportation 7317:entanglement-assisted 7147:DiVincenzo's criteria 6943: 6904: 6868:, and it arises from 6816: 6778: 6715: 6683: 6587: 6397: 6329: 6294: 6262: 6233: 6198: 6151: 6122: 6092: 6057: 6010: 5980: 5978:{\displaystyle \Psi } 5946: 5910: 5804: 5737: 5704: 5638: 5608: 5606:{\displaystyle \Psi } 5564: 5486: 5439: 5405: 5382: 5286: 5143: 5059: 4995: 4926: 4849: 4847:{\displaystyle \Phi } 4829: 4797: 4752: 4750:{\displaystyle \Phi } 4729: 4627: 4612:to the ideal channel 4607: 4605:{\displaystyle \Phi } 4579: 4559: 4539: 4537:{\displaystyle \Phi } 4493: 4451: 4423: 4390:time-bin entanglement 4370:quantum teleportation 4351: 4349:{\displaystyle \Psi } 4327: 4325:{\displaystyle \Psi } 4281: 4227: 4197: 4195:{\displaystyle \Psi } 4170: 4102: 4100:{\displaystyle \Psi } 4082: 4080:{\displaystyle \Psi } 4053:channel-state duality 4032: 3947: 3870: 3755: 3604: 3602:{\displaystyle \Phi } 3566: 3448: 3446:{\displaystyle \Phi } 3397: 3288: 3250: 3248:{\displaystyle \Psi } 3230: 3167: 3122: 3092: 2963: 2869: 2740: 2696: 2661: 2659:{\displaystyle \Phi } 2641: 2576: 2462: 2353: 2323: 2321:{\displaystyle \Psi } 2292: 2220: 2132: 2130:{\displaystyle \Psi } 2105: 2062: 2060:{\displaystyle F_{i}} 2035: 2033:{\displaystyle F_{i}} 2005: 1951: 1903: 1834:the reduced state of 1826: 1774: 1723: 1666: 1613: 1538: 1518: 1482: 1458: 1438: 1384: 1299: 1272: 1239: 1210: 1190: 1170: 1138: 1081: 1014:Classical information 1005: 959: 932: 930:{\displaystyle \Phi } 901: 866: 864:{\displaystyle \Phi } 843: 762: 760:{\displaystyle \Phi } 742: 641: 639:{\displaystyle \Phi } 621: 594: 592:{\displaystyle \Phi } 574: 572:{\displaystyle \Phi } 528: 526:{\displaystyle \Phi } 496: 494:{\displaystyle \Phi } 465: 423: 372: 370:{\displaystyle \Phi } 348: 346:{\displaystyle \Phi } 325: 323:{\displaystyle \Phi } 301: 299:{\displaystyle H_{B}} 274: 272:{\displaystyle H_{A}} 243: 241:{\displaystyle \Phi } 219: 189: 149: 147:{\displaystyle H_{B}} 122: 120:{\displaystyle H_{A}} 8710:Quantum field theory 8639:Quantum metamaterial 8584:Quantum cryptography 8314:Consistent histories 7566:processor benchmarks 7495:Quantum optimization 7378:Quantum cryptography 7189:physical vs. logical 6917: 6884: 6790: 6734: 6695: 6645: 6415: 6341: 6303: 6274: 6242: 6207: 6172: 6156:. Thus for a purely 6131: 6101: 6097:, the ideal channel 6077: 6020: 5989: 5969: 5965:channel capacity of 5922: 5817: 5746: 5713: 5653: 5617: 5597: 5501: 5456: 5418: 5410:operation describes 5394: 5312: 5178: 5071: 5004: 4950: 4861: 4838: 4809: 4767: 4741: 4639: 4616: 4596: 4568: 4548: 4528: 4460: 4432: 4404: 4398:quantum cryptography 4340: 4316: 4209: 4186: 4114: 4091: 4071: 3959: 3893: 3770: 3619: 3593: 3467: 3437: 3413:Suppose two parties 3300: 3262: 3239: 3176: 3131: 3104: 2978: 2884: 2752: 2705: 2670: 2650: 2598: 2485: 2365: 2335: 2312: 2300:In other words, one 2235: 2144: 2121: 2071: 2044: 2017: 1979: 1918: 1865: 1854:with respect to the 1786: 1740: 1690: 1625: 1579: 1527: 1491: 1467: 1447: 1396: 1311: 1284: 1252: 1237:{\displaystyle C(X)} 1219: 1199: 1179: 1168:{\displaystyle C(X)} 1150: 1104: 1026: 972: 941: 921: 883: 855: 774: 751: 687: 630: 603: 583: 563: 517: 485: 470:is positive for all 441: 396: 361: 337: 314: 283: 256: 232: 198: 162: 131: 104: 9058:Phased-array optics 9016:Acoustic levitation 8695:Quantum fluctuation 8664:Quantum programming 8624:Quantum logic gates 8609:Quantum information 8589:Quantum electronics 8049:Classical mechanics 7279:Quantum speed limit 7174:Quantum programming 7169:Quantum information 7079:2011arXiv1106.1445W 7011:2012RvMP...84..621W 5895: 5593:achievable rate of 5555: 5335: 4275: 4202:must take the form 3941: 3923: 3880:measure-and-prepare 3456:simply consists of 3161: 2474:, and invoking the 476:completely positive 330:needs to be linear. 226:Schrödinger picture 89:Schrödinger picture 55:completely positive 40:quantum information 8748:in popular culture 8530:Quantum algorithms 8378:Von Neumann–Wigner 8358:Objective collapse 8054:Old quantum theory 7928:Forest/Rigetti QCS 7664:quantum logic gate 7450:Bernstein–Vazirani 7437:Quantum algorithms 7312:Classical capacity 7196:Quantum processors 7179:Quantum simulation 6938: 6899: 6844:. You can help by 6811: 6773: 6710: 6678: 6638:of a channel Κ is 6636:classical capacity 6582: 6392: 6324: 6289: 6257: 6228: 6193: 6146: 6117: 6087: 6069:Important examples 6052: 6005: 5975: 5941: 5905: 5868: 5829: 5799: 5761: 5732: 5699: 5649:For all sequences 5633: 5603: 5559: 5535: 5481: 5434: 5400: 5377: 5315: 5281: 5236: 5169:best case scenario 5155:is an encoder and 5138: 5054: 4990: 4921: 4895: 4844: 4824: 4792: 4747: 4724: 4632:can be defined by 4622: 4602: 4574: 4554: 4534: 4488: 4446: 4418: 4346: 4322: 4276: 4261: 4192: 4165: 4097: 4077: 4027: 3994: 3942: 3927: 3909: 3865: 3832: 3750: 3717: 3695: 3599: 3561: 3552: 3443: 3392: 3368: 3336: 3283: 3255:is CP and unital. 3245: 3225: 3162: 3147: 3117: 3087: 3081: 2958: 2934: 2864: 2855: 2735: 2691: 2656: 2636: 2592:quantum instrument 2571: 2562: 2457: 2448: 2348: 2328:is CP and unital. 2318: 2287: 2263: 2215: 2194: 2127: 2100: 2083: 2057: 2030: 2000: 1946: 1898: 1821: 1769: 1718: 1661: 1608: 1553:Frobenius category 1545:quantum instrument 1533: 1513: 1477: 1453: 1433: 1379: 1294: 1267: 1234: 1205: 1185: 1165: 1133: 1076: 1000: 954: 927: 910:to observables on 896: 861: 838: 757: 737: 648:Heisenberg picture 636: 616: 589: 569: 537:Heisenberg picture 523: 491: 460: 418: 367: 353:must preserve the 343: 320: 296: 269: 238: 214: 184: 144: 117: 83:information theory 9095: 9094: 9071: 9070: 8878:complexity theory 8863:cellular automata 8791: 8790: 8765:Quantum mysticism 8743:Schrödinger's cat 8674:Quantum simulator 8644:Quantum metrology 8572:Quantum computing 8535:Quantum amplifier 8512:Quantum spacetime 8477:Quantum cosmology 8467:Quantum chemistry 8167:Scattering theory 8115:Zero-point energy 8110:Degenerate levels 8018:Quantum mechanics 7984: 7983: 7895: 7894: 7792:Linear optical QC 7573:Quantum supremacy 7527:complexity theory 7480:Quantum annealing 7431: 7430: 7368:Superdense coding 7157:Quantum computing 6862: 6861: 6624:two bit per qubit 6620:Superdense coding 6605:one bit per qubit 6577: 5846: 5820: 5752: 5520: 5469: 5249: 5221: 5196: 5083: 4886: 3985: 3823: 3708: 3359: 3327: 3312: 2254: 2074: 1549:Frobenius algebra 1536:{\displaystyle x} 1456:{\displaystyle a} 1208:{\displaystyle X} 1188:{\displaystyle X} 95:quantum operation 59:quantum operation 16:(Redirected from 9115: 9083: 9082: 8960:machine learning 8935:key distribution 8920:image processing 8910:error correction 8836: 8835: 8818: 8811: 8804: 8795: 8794: 8781: 8780: 8492:Quantum geometry 8487:Quantum dynamics 8344:Superdeterminism 8276:Rarita–Schwinger 8225:Matrix mechanics 8080:Bra–ket notation 8011: 8004: 7997: 7988: 7987: 7974: 7973: 7964: 7963: 7770: 7769: 7700:error correction 7629:computing models 7595:Relaxation times 7485:Quantum counting 7374: 7373: 7322:quantum capacity 7269:No-teleportation 7254:No-communication 7126: 7119: 7112: 7103: 7102: 7097: 7072: 7044: 7037: 7031: 7030: 7004: 6984: 6947: 6945: 6944: 6939: 6908: 6906: 6905: 6900: 6866:channel fidelity 6857: 6854: 6836: 6829: 6825:Channel fidelity 6820: 6818: 6817: 6812: 6810: 6809: 6798: 6782: 6780: 6779: 6774: 6766: 6765: 6754: 6725:quantum capacity 6719: 6717: 6716: 6711: 6709: 6708: 6703: 6687: 6685: 6684: 6679: 6671: 6670: 6665: 6591: 6589: 6588: 6583: 6578: 6576: 6565: 6554: 6546: 6545: 6540: 6531: 6530: 6519: 6501: 6500: 6489: 6480: 6479: 6468: 6450: 6449: 6444: 6435: 6434: 6429: 6401: 6399: 6398: 6393: 6382: 6381: 6370: 6361: 6360: 6355: 6333: 6331: 6330: 6325: 6323: 6322: 6311: 6298: 6296: 6295: 6290: 6288: 6287: 6282: 6266: 6264: 6263: 6258: 6256: 6255: 6250: 6237: 6235: 6234: 6229: 6227: 6226: 6215: 6202: 6200: 6199: 6194: 6192: 6191: 6180: 6155: 6153: 6152: 6147: 6145: 6144: 6143: 6126: 6124: 6123: 6118: 6116: 6115: 6096: 6094: 6093: 6088: 6086: 6085: 6061: 6059: 6058: 6053: 6048: 6047: 6014: 6012: 6011: 6006: 6004: 6003: 5985:with respect to 5984: 5982: 5981: 5976: 5950: 5948: 5947: 5942: 5937: 5936: 5914: 5912: 5911: 5906: 5894: 5893: 5892: 5879: 5864: 5863: 5862: 5861: 5848: 5847: 5839: 5828: 5808: 5806: 5805: 5800: 5789: 5788: 5779: 5774: 5773: 5760: 5741: 5739: 5738: 5733: 5725: 5724: 5708: 5706: 5705: 5700: 5698: 5687: 5686: 5668: 5667: 5642: 5640: 5639: 5634: 5632: 5631: 5613:with respect to 5612: 5610: 5609: 5604: 5568: 5566: 5565: 5560: 5554: 5546: 5531: 5530: 5522: 5521: 5513: 5490: 5488: 5487: 5482: 5480: 5479: 5471: 5470: 5462: 5443: 5441: 5440: 5435: 5433: 5432: 5409: 5407: 5406: 5401: 5386: 5384: 5383: 5378: 5373: 5372: 5351: 5350: 5334: 5326: 5290: 5288: 5287: 5282: 5280: 5279: 5267: 5266: 5251: 5250: 5242: 5235: 5214: 5213: 5198: 5197: 5189: 5147: 5145: 5144: 5139: 5137: 5136: 5131: 5130: 5120: 5119: 5114: 5113: 5085: 5084: 5076: 5063: 5061: 5060: 5055: 5053: 5052: 5047: 5046: 5036: 5035: 5030: 5029: 5019: 5018: 4999: 4997: 4996: 4991: 4989: 4988: 4983: 4982: 4972: 4971: 4966: 4965: 4930: 4928: 4927: 4922: 4914: 4913: 4894: 4882: 4881: 4853: 4851: 4850: 4845: 4833: 4831: 4830: 4825: 4801: 4799: 4798: 4793: 4788: 4787: 4756: 4754: 4753: 4748: 4733: 4731: 4730: 4725: 4701: 4631: 4629: 4628: 4623: 4611: 4609: 4608: 4603: 4583: 4581: 4580: 4575: 4563: 4561: 4560: 4555: 4543: 4541: 4540: 4535: 4507:Channel capacity 4497: 4495: 4494: 4489: 4481: 4467: 4455: 4453: 4452: 4447: 4439: 4427: 4425: 4424: 4419: 4411: 4355: 4353: 4352: 4347: 4331: 4329: 4328: 4323: 4285: 4283: 4282: 4277: 4274: 4269: 4257: 4256: 4246: 4241: 4201: 4199: 4198: 4193: 4174: 4172: 4171: 4166: 4161: 4160: 4149: 4140: 4139: 4128: 4106: 4104: 4103: 4098: 4086: 4084: 4083: 4078: 4036: 4034: 4033: 4028: 4023: 4022: 4004: 4003: 3993: 3972: 3971: 3951: 3949: 3948: 3943: 3940: 3935: 3922: 3917: 3905: 3904: 3874: 3872: 3871: 3866: 3861: 3860: 3848: 3847: 3831: 3810: 3809: 3797: 3796: 3759: 3757: 3756: 3751: 3746: 3745: 3733: 3732: 3716: 3704: 3700: 3699: 3689: 3688: 3659: 3658: 3631: 3630: 3608: 3606: 3605: 3600: 3570: 3568: 3567: 3562: 3557: 3556: 3546: 3545: 3516: 3515: 3480: 3479: 3452: 3450: 3449: 3444: 3401: 3399: 3398: 3393: 3391: 3390: 3378: 3377: 3367: 3346: 3345: 3335: 3314: 3313: 3305: 3292: 3290: 3289: 3284: 3254: 3252: 3251: 3246: 3234: 3232: 3231: 3226: 3224: 3223: 3211: 3210: 3189: 3188: 3171: 3169: 3168: 3163: 3160: 3155: 3143: 3142: 3126: 3124: 3123: 3118: 3116: 3115: 3096: 3094: 3093: 3088: 3086: 3085: 3069: 3068: 3059: 3058: 3029: 3028: 3019: 3018: 2967: 2965: 2964: 2959: 2939: 2938: 2931: 2930: 2910: 2909: 2873: 2871: 2870: 2865: 2860: 2859: 2852: 2851: 2836: 2835: 2809: 2808: 2793: 2792: 2744: 2742: 2741: 2736: 2700: 2698: 2697: 2692: 2665: 2663: 2662: 2657: 2645: 2643: 2642: 2637: 2632: 2631: 2613: 2612: 2580: 2578: 2577: 2572: 2567: 2566: 2556: 2555: 2526: 2525: 2466: 2464: 2463: 2458: 2453: 2452: 2436: 2435: 2403: 2402: 2357: 2355: 2354: 2349: 2347: 2346: 2327: 2325: 2324: 2319: 2306:against the POVM 2296: 2294: 2293: 2288: 2283: 2282: 2273: 2272: 2262: 2224: 2222: 2221: 2216: 2199: 2198: 2191: 2190: 2170: 2169: 2136: 2134: 2133: 2128: 2109: 2107: 2106: 2101: 2093: 2092: 2082: 2066: 2064: 2063: 2058: 2056: 2055: 2039: 2037: 2036: 2031: 2029: 2028: 2009: 2007: 2006: 2001: 1999: 1991: 1990: 1955: 1953: 1952: 1947: 1942: 1941: 1907: 1905: 1904: 1899: 1890: 1889: 1877: 1876: 1830: 1828: 1827: 1822: 1817: 1816: 1804: 1803: 1778: 1776: 1775: 1770: 1765: 1764: 1752: 1751: 1727: 1725: 1724: 1719: 1708: 1707: 1670: 1668: 1667: 1662: 1660: 1659: 1655: 1617: 1615: 1614: 1609: 1604: 1603: 1542: 1540: 1539: 1534: 1522: 1520: 1519: 1514: 1509: 1508: 1486: 1484: 1483: 1478: 1476: 1475: 1463:of a C*-algebra 1462: 1460: 1459: 1454: 1442: 1440: 1439: 1434: 1414: 1413: 1388: 1386: 1385: 1380: 1372: 1371: 1335: 1334: 1303: 1301: 1300: 1295: 1293: 1292: 1276: 1274: 1273: 1268: 1266: 1265: 1260: 1243: 1241: 1240: 1235: 1214: 1212: 1211: 1206: 1194: 1192: 1191: 1186: 1174: 1172: 1171: 1166: 1142: 1140: 1139: 1134: 1129: 1128: 1119: 1118: 1085: 1083: 1082: 1077: 1072: 1071: 1050: 1049: 1009: 1007: 1006: 1001: 984: 983: 963: 961: 960: 955: 953: 952: 936: 934: 933: 928: 905: 903: 902: 897: 895: 894: 871:takes states on 870: 868: 867: 862: 847: 845: 844: 839: 816: 815: 766: 764: 763: 758: 746: 744: 743: 738: 733: 732: 711: 710: 645: 643: 642: 637: 625: 623: 622: 617: 615: 614: 598: 596: 595: 590: 578: 576: 575: 570: 532: 530: 529: 524: 500: 498: 497: 492: 469: 467: 466: 461: 453: 452: 427: 425: 424: 419: 408: 407: 376: 374: 373: 368: 352: 350: 349: 344: 329: 327: 326: 321: 305: 303: 302: 297: 295: 294: 278: 276: 275: 270: 268: 267: 250:density matrices 247: 245: 244: 239: 223: 221: 220: 215: 210: 209: 193: 191: 190: 185: 180: 179: 153: 151: 150: 145: 143: 142: 126: 124: 123: 118: 116: 115: 63:reduced dynamics 21: 9123: 9122: 9118: 9117: 9116: 9114: 9113: 9112: 9098: 9097: 9096: 9091: 9067: 9004: 8915:finite automata 8827: 8822: 8792: 8787: 8769: 8755:Wigner's friend 8731: 8722:Quantum gravity 8683: 8669:Quantum sensing 8649:Quantum network 8629:Quantum machine 8599:Quantum imaging 8562:Quantum circuit 8557:Quantum channel 8516: 8462:Quantum biology 8448: 8424:Elitzur–Vaidman 8399:Davisson–Germer 8382: 8334:Hidden-variable 8324:de Broglie–Bohm 8301:Interpretations 8295: 8244: 8198: 8085:Complementarity 8063: 8020: 8015: 7985: 7980: 7952: 7902: 7891: 7864:Superconducting 7858: 7824: 7815:Neutral atom QC 7807:Ultracold atoms 7801: 7766:implementations 7765: 7759: 7699: 7692: 7659:Quantum circuit 7627: 7621: 7615: 7605: 7565: 7559: 7526: 7519: 7475:Hidden subgroup 7427: 7416:other protocols 7372: 7349:quantum network 7344:Quantum channel 7304: 7298: 7244:No-broadcasting 7234:Gottesman–Knill 7207: 7135: 7130: 7048: 7047: 7038: 7034: 6985: 6981: 6976: 6954: 6918: 6915: 6914: 6885: 6882: 6881: 6878: 6858: 6852: 6849: 6842:needs expansion 6827: 6799: 6794: 6793: 6791: 6788: 6787: 6755: 6750: 6749: 6735: 6732: 6731: 6704: 6699: 6698: 6696: 6693: 6692: 6666: 6661: 6660: 6646: 6643: 6642: 6632: 6566: 6555: 6553: 6541: 6536: 6535: 6520: 6515: 6514: 6490: 6485: 6484: 6469: 6464: 6463: 6445: 6440: 6439: 6430: 6425: 6424: 6416: 6413: 6412: 6371: 6366: 6365: 6356: 6351: 6350: 6342: 6339: 6338: 6312: 6307: 6306: 6304: 6301: 6300: 6283: 6278: 6277: 6275: 6272: 6271: 6251: 6246: 6245: 6243: 6240: 6239: 6216: 6211: 6210: 6208: 6205: 6204: 6181: 6176: 6175: 6173: 6170: 6169: 6139: 6138: 6134: 6132: 6129: 6128: 6108: 6104: 6102: 6099: 6098: 6081: 6080: 6078: 6075: 6074: 6071: 6040: 6036: 6021: 6018: 6017: 5996: 5992: 5990: 5987: 5986: 5970: 5967: 5966: 5932: 5928: 5923: 5920: 5919: 5888: 5884: 5880: 5872: 5857: 5853: 5849: 5838: 5837: 5836: 5824: 5818: 5815: 5814: 5784: 5780: 5775: 5769: 5765: 5756: 5747: 5744: 5743: 5720: 5716: 5714: 5711: 5710: 5694: 5682: 5678: 5663: 5659: 5654: 5651: 5650: 5624: 5620: 5618: 5615: 5614: 5598: 5595: 5594: 5547: 5539: 5523: 5512: 5511: 5510: 5502: 5499: 5498: 5472: 5461: 5460: 5459: 5457: 5454: 5453: 5452:corresponds to 5425: 5421: 5419: 5416: 5415: 5395: 5392: 5391: 5365: 5361: 5343: 5339: 5327: 5319: 5313: 5310: 5309: 5272: 5268: 5259: 5255: 5241: 5240: 5225: 5206: 5202: 5188: 5187: 5179: 5176: 5175: 5132: 5126: 5125: 5124: 5115: 5109: 5108: 5107: 5075: 5074: 5072: 5069: 5068: 5048: 5042: 5041: 5040: 5031: 5025: 5024: 5023: 5011: 5007: 5005: 5002: 5001: 4984: 4978: 4977: 4976: 4967: 4961: 4960: 4959: 4951: 4948: 4947: 4937: 4909: 4905: 4890: 4874: 4870: 4862: 4859: 4858: 4839: 4836: 4835: 4810: 4807: 4806: 4783: 4779: 4768: 4765: 4764: 4742: 4739: 4738: 4697: 4640: 4637: 4636: 4617: 4614: 4613: 4597: 4594: 4593: 4569: 4566: 4565: 4549: 4546: 4545: 4529: 4526: 4525: 4514: 4509: 4477: 4463: 4461: 4458: 4457: 4435: 4433: 4430: 4429: 4407: 4405: 4402: 4401: 4378: 4366: 4341: 4338: 4337: 4317: 4314: 4313: 4309:Kraus operators 4305: 4297:. The matrices 4270: 4265: 4252: 4248: 4242: 4231: 4210: 4207: 4206: 4187: 4184: 4183: 4150: 4145: 4144: 4129: 4124: 4123: 4115: 4112: 4111: 4092: 4089: 4088: 4072: 4069: 4068: 4065: 4018: 4014: 3999: 3995: 3989: 3967: 3963: 3960: 3957: 3956: 3936: 3931: 3918: 3913: 3900: 3896: 3894: 3891: 3890: 3856: 3852: 3843: 3839: 3827: 3805: 3801: 3792: 3788: 3771: 3768: 3767: 3741: 3737: 3728: 3724: 3712: 3694: 3693: 3684: 3680: 3671: 3670: 3664: 3663: 3654: 3650: 3637: 3636: 3632: 3626: 3622: 3620: 3617: 3616: 3611: 3594: 3591: 3590: 3587: 3551: 3550: 3541: 3537: 3528: 3527: 3521: 3520: 3511: 3507: 3494: 3493: 3475: 3471: 3468: 3465: 3464: 3455: 3438: 3435: 3434: 3411: 3386: 3382: 3373: 3369: 3363: 3341: 3337: 3331: 3304: 3303: 3301: 3298: 3297: 3263: 3260: 3259: 3240: 3237: 3236: 3219: 3215: 3206: 3202: 3184: 3180: 3177: 3174: 3173: 3156: 3151: 3138: 3134: 3132: 3129: 3128: 3111: 3107: 3105: 3102: 3101: 3080: 3079: 3064: 3060: 3054: 3050: 3047: 3046: 3040: 3039: 3024: 3020: 3014: 3010: 3003: 3002: 2979: 2976: 2975: 2933: 2932: 2926: 2922: 2919: 2918: 2912: 2911: 2905: 2901: 2894: 2893: 2885: 2882: 2881: 2854: 2853: 2847: 2843: 2831: 2827: 2818: 2817: 2811: 2810: 2804: 2800: 2788: 2784: 2771: 2770: 2753: 2750: 2749: 2706: 2703: 2702: 2671: 2668: 2667: 2651: 2648: 2647: 2627: 2623: 2608: 2604: 2599: 2596: 2595: 2587: 2561: 2560: 2551: 2547: 2538: 2537: 2531: 2530: 2521: 2517: 2504: 2503: 2486: 2483: 2482: 2447: 2446: 2431: 2427: 2421: 2420: 2414: 2413: 2398: 2394: 2384: 2383: 2366: 2363: 2362: 2342: 2338: 2336: 2333: 2332: 2313: 2310: 2309: 2278: 2274: 2268: 2264: 2258: 2236: 2233: 2232: 2193: 2192: 2186: 2182: 2179: 2178: 2172: 2171: 2165: 2161: 2154: 2153: 2145: 2142: 2141: 2122: 2119: 2118: 2088: 2084: 2078: 2072: 2069: 2068: 2051: 2047: 2045: 2042: 2041: 2024: 2020: 2018: 2015: 2014: 1995: 1986: 1982: 1980: 1977: 1976: 1973: 1937: 1933: 1919: 1916: 1915: 1885: 1881: 1872: 1868: 1866: 1863: 1862: 1812: 1808: 1799: 1795: 1787: 1784: 1783: 1760: 1756: 1747: 1743: 1741: 1738: 1737: 1734: 1703: 1699: 1691: 1688: 1687: 1651: 1638: 1634: 1626: 1623: 1622: 1599: 1595: 1580: 1577: 1576: 1566: 1561: 1528: 1525: 1524: 1504: 1500: 1492: 1489: 1488: 1471: 1470: 1468: 1465: 1464: 1448: 1445: 1444: 1409: 1405: 1397: 1394: 1393: 1367: 1363: 1330: 1326: 1312: 1309: 1308: 1288: 1287: 1285: 1282: 1281: 1261: 1256: 1255: 1253: 1250: 1249: 1220: 1217: 1216: 1200: 1197: 1196: 1180: 1177: 1176: 1151: 1148: 1147: 1124: 1123: 1114: 1113: 1105: 1102: 1101: 1067: 1063: 1045: 1041: 1027: 1024: 1023: 1016: 979: 975: 973: 970: 969: 948: 944: 942: 939: 938: 922: 919: 918: 890: 886: 884: 881: 880: 856: 853: 852: 811: 807: 775: 772: 771: 752: 749: 748: 728: 724: 706: 702: 688: 685: 684: 681:Hilbert–Schmidt 678: 665: 631: 628: 627: 610: 606: 604: 601: 600: 584: 581: 580: 564: 561: 560: 553: 546: 539: 518: 515: 514: 505:The adjectives 486: 483: 482: 448: 444: 442: 439: 438: 436: 403: 399: 397: 394: 393: 362: 359: 358: 338: 335: 334: 315: 312: 311: 290: 286: 284: 281: 280: 263: 259: 257: 254: 253: 233: 230: 229: 205: 201: 199: 196: 195: 175: 171: 163: 160: 159: 138: 134: 132: 129: 128: 111: 107: 105: 102: 101: 91: 72: 36:quantum channel 28: 23: 22: 15: 12: 11: 5: 9121: 9111: 9110: 9093: 9092: 9090: 9089: 9076: 9073: 9072: 9069: 9068: 9066: 9065: 9060: 9055: 9050: 9045: 9044: 9043: 9033: 9028: 9023: 9018: 9012: 9010: 9006: 9005: 9003: 9002: 8997: 8992: 8987: 8982: 8977: 8975:neural network 8972: 8967: 8962: 8957: 8952: 8947: 8942: 8937: 8932: 8927: 8922: 8917: 8912: 8907: 8902: 8897: 8896: 8895: 8885: 8880: 8875: 8870: 8865: 8860: 8855: 8850: 8844: 8842: 8833: 8829: 8828: 8821: 8820: 8813: 8806: 8798: 8789: 8788: 8786: 8785: 8774: 8771: 8770: 8768: 8767: 8762: 8757: 8752: 8751: 8750: 8739: 8737: 8733: 8732: 8730: 8729: 8724: 8719: 8718: 8717: 8707: 8702: 8700:Casimir effect 8697: 8691: 8689: 8685: 8684: 8682: 8681: 8676: 8671: 8666: 8661: 8659:Quantum optics 8656: 8651: 8646: 8641: 8636: 8631: 8626: 8621: 8616: 8611: 8606: 8601: 8596: 8591: 8586: 8581: 8580: 8579: 8569: 8564: 8559: 8554: 8553: 8552: 8542: 8537: 8532: 8526: 8524: 8518: 8517: 8515: 8514: 8509: 8504: 8499: 8494: 8489: 8484: 8479: 8474: 8469: 8464: 8458: 8456: 8450: 8449: 8447: 8446: 8441: 8436: 8434:Quantum eraser 8431: 8426: 8421: 8416: 8411: 8406: 8401: 8396: 8390: 8388: 8384: 8383: 8381: 8380: 8375: 8370: 8365: 8360: 8355: 8350: 8349: 8348: 8347: 8346: 8331: 8326: 8321: 8316: 8311: 8305: 8303: 8297: 8296: 8294: 8293: 8288: 8283: 8278: 8273: 8268: 8263: 8258: 8252: 8250: 8246: 8245: 8243: 8242: 8237: 8232: 8227: 8222: 8217: 8212: 8206: 8204: 8200: 8199: 8197: 8196: 8195: 8194: 8189: 8179: 8174: 8169: 8164: 8159: 8154: 8149: 8144: 8139: 8134: 8129: 8124: 8119: 8118: 8117: 8112: 8107: 8102: 8092: 8090:Density matrix 8087: 8082: 8077: 8071: 8069: 8065: 8064: 8062: 8061: 8056: 8051: 8046: 8045: 8044: 8034: 8028: 8026: 8022: 8021: 8014: 8013: 8006: 7999: 7991: 7982: 7981: 7979: 7978: 7968: 7957: 7954: 7953: 7951: 7950: 7948:many others... 7945: 7940: 7935: 7930: 7921: 7907: 7905: 7897: 7896: 7893: 7892: 7890: 7889: 7884: 7879: 7874: 7868: 7866: 7860: 7859: 7857: 7856: 7851: 7846: 7841: 7835: 7833: 7826: 7825: 7823: 7822: 7820:Trapped-ion QC 7817: 7811: 7809: 7803: 7802: 7800: 7799: 7794: 7789: 7784: 7778: 7776: 7774:Quantum optics 7767: 7761: 7760: 7758: 7757: 7752: 7751: 7750: 7743: 7738: 7733: 7728: 7723: 7718: 7713: 7704: 7702: 7694: 7693: 7691: 7690: 7685: 7680: 7679: 7678: 7668: 7667: 7666: 7656: 7655: 7654: 7644: 7639: 7633: 7631: 7623: 7622: 7620: 7619: 7618: 7617: 7613: 7607: 7603: 7592: 7591: 7590: 7580: 7578:Quantum volume 7575: 7569: 7567: 7561: 7560: 7558: 7557: 7552: 7547: 7542: 7537: 7531: 7529: 7521: 7520: 7518: 7517: 7512: 7507: 7502: 7497: 7492: 7487: 7482: 7477: 7472: 7467: 7462: 7457: 7455:Boson sampling 7452: 7447: 7441: 7439: 7433: 7432: 7429: 7428: 7426: 7425: 7420: 7419: 7418: 7413: 7408: 7398: 7393: 7388: 7382: 7380: 7371: 7370: 7365: 7364: 7363: 7353: 7352: 7351: 7341: 7336: 7331: 7326: 7325: 7324: 7319: 7308: 7306: 7300: 7299: 7297: 7296: 7291: 7289:Solovay–Kitaev 7286: 7281: 7276: 7271: 7266: 7261: 7256: 7251: 7246: 7241: 7236: 7231: 7226: 7221: 7215: 7213: 7209: 7208: 7206: 7205: 7204: 7203: 7193: 7192: 7191: 7181: 7176: 7171: 7166: 7165: 7164: 7154: 7149: 7143: 7141: 7137: 7136: 7129: 7128: 7121: 7114: 7106: 7100: 7099: 7056: 7046: 7045: 7032: 6995:(2): 621–669. 6978: 6977: 6975: 6972: 6971: 6970: 6965: 6960: 6953: 6950: 6937: 6934: 6931: 6928: 6925: 6922: 6898: 6895: 6892: 6889: 6877: 6874: 6860: 6859: 6839: 6837: 6826: 6823: 6808: 6805: 6802: 6797: 6784: 6783: 6772: 6769: 6764: 6761: 6758: 6753: 6748: 6745: 6742: 6739: 6723:Similarly the 6707: 6702: 6689: 6688: 6677: 6674: 6669: 6664: 6659: 6656: 6653: 6650: 6631: 6628: 6593: 6592: 6581: 6575: 6572: 6569: 6564: 6561: 6558: 6552: 6549: 6544: 6539: 6534: 6529: 6526: 6523: 6518: 6513: 6510: 6507: 6504: 6499: 6496: 6493: 6488: 6483: 6478: 6475: 6472: 6467: 6462: 6459: 6456: 6453: 6448: 6443: 6438: 6433: 6428: 6423: 6420: 6403: 6402: 6391: 6388: 6385: 6380: 6377: 6374: 6369: 6364: 6359: 6354: 6349: 6346: 6321: 6318: 6315: 6310: 6286: 6281: 6254: 6249: 6225: 6222: 6219: 6214: 6190: 6187: 6184: 6179: 6142: 6137: 6114: 6111: 6107: 6084: 6070: 6067: 6051: 6046: 6043: 6039: 6035: 6032: 6029: 6026: 6002: 5999: 5995: 5974: 5940: 5935: 5931: 5927: 5916: 5915: 5904: 5901: 5898: 5891: 5887: 5883: 5878: 5875: 5871: 5867: 5860: 5856: 5852: 5845: 5842: 5835: 5832: 5827: 5823: 5811: 5810: 5798: 5795: 5792: 5787: 5783: 5778: 5772: 5768: 5764: 5759: 5755: 5751: 5731: 5728: 5723: 5719: 5697: 5693: 5690: 5685: 5681: 5677: 5674: 5671: 5666: 5662: 5658: 5646: 5645: 5630: 5627: 5623: 5602: 5570: 5569: 5558: 5553: 5550: 5545: 5542: 5538: 5534: 5529: 5526: 5519: 5516: 5509: 5506: 5478: 5475: 5468: 5465: 5431: 5428: 5424: 5399: 5388: 5387: 5376: 5371: 5368: 5364: 5360: 5357: 5354: 5349: 5346: 5342: 5338: 5333: 5330: 5325: 5322: 5318: 5292: 5291: 5278: 5275: 5271: 5265: 5262: 5258: 5254: 5248: 5245: 5239: 5234: 5231: 5228: 5224: 5220: 5217: 5212: 5209: 5205: 5201: 5195: 5192: 5186: 5183: 5149: 5148: 5135: 5129: 5123: 5118: 5112: 5106: 5103: 5100: 5097: 5094: 5091: 5088: 5082: 5079: 5051: 5045: 5039: 5034: 5028: 5022: 5017: 5014: 5010: 4987: 4981: 4975: 4970: 4964: 4958: 4955: 4936: 4933: 4932: 4931: 4920: 4917: 4912: 4908: 4904: 4901: 4898: 4893: 4889: 4885: 4880: 4877: 4873: 4869: 4866: 4843: 4823: 4820: 4817: 4814: 4803: 4802: 4791: 4786: 4782: 4778: 4775: 4772: 4746: 4735: 4734: 4723: 4720: 4717: 4714: 4711: 4708: 4705: 4700: 4695: 4692: 4689: 4686: 4683: 4680: 4677: 4674: 4671: 4668: 4665: 4662: 4659: 4656: 4653: 4650: 4647: 4644: 4621: 4601: 4573: 4553: 4533: 4513: 4510: 4508: 4505: 4487: 4484: 4480: 4476: 4473: 4470: 4466: 4445: 4442: 4438: 4417: 4414: 4410: 4377: 4374: 4365: 4362: 4345: 4321: 4301: 4287: 4286: 4273: 4268: 4264: 4260: 4255: 4251: 4245: 4240: 4237: 4234: 4230: 4226: 4223: 4220: 4217: 4214: 4191: 4176: 4175: 4164: 4159: 4156: 4153: 4148: 4143: 4138: 4135: 4132: 4127: 4122: 4119: 4096: 4076: 4064: 4061: 4038: 4037: 4026: 4021: 4017: 4013: 4010: 4007: 4002: 3998: 3992: 3988: 3984: 3981: 3978: 3975: 3970: 3966: 3952:is defined by 3939: 3934: 3930: 3926: 3921: 3916: 3912: 3908: 3903: 3899: 3876: 3875: 3864: 3859: 3855: 3851: 3846: 3842: 3838: 3835: 3830: 3826: 3822: 3819: 3816: 3813: 3808: 3804: 3800: 3795: 3791: 3787: 3784: 3781: 3778: 3775: 3761: 3760: 3749: 3744: 3740: 3736: 3731: 3727: 3723: 3720: 3715: 3711: 3707: 3703: 3698: 3692: 3687: 3683: 3679: 3676: 3673: 3672: 3669: 3666: 3665: 3662: 3657: 3653: 3649: 3646: 3643: 3642: 3640: 3635: 3629: 3625: 3609: 3598: 3585: 3572: 3571: 3560: 3555: 3549: 3544: 3540: 3536: 3533: 3530: 3529: 3526: 3523: 3522: 3519: 3514: 3510: 3506: 3503: 3500: 3499: 3497: 3492: 3489: 3486: 3483: 3478: 3474: 3453: 3442: 3410: 3407: 3403: 3402: 3389: 3385: 3381: 3376: 3372: 3366: 3362: 3358: 3355: 3352: 3349: 3344: 3340: 3334: 3330: 3326: 3323: 3320: 3317: 3311: 3308: 3282: 3279: 3276: 3273: 3270: 3267: 3244: 3235:. We see that 3222: 3218: 3214: 3209: 3205: 3201: 3198: 3195: 3192: 3187: 3183: 3159: 3154: 3150: 3146: 3141: 3137: 3114: 3110: 3098: 3097: 3084: 3078: 3075: 3072: 3067: 3063: 3057: 3053: 3049: 3048: 3045: 3042: 3041: 3038: 3035: 3032: 3027: 3023: 3017: 3013: 3009: 3008: 3006: 3001: 2998: 2995: 2992: 2989: 2986: 2983: 2969: 2968: 2957: 2954: 2951: 2948: 2945: 2942: 2937: 2929: 2925: 2921: 2920: 2917: 2914: 2913: 2908: 2904: 2900: 2899: 2897: 2892: 2889: 2875: 2874: 2863: 2858: 2850: 2846: 2842: 2839: 2834: 2830: 2826: 2823: 2820: 2819: 2816: 2813: 2812: 2807: 2803: 2799: 2796: 2791: 2787: 2783: 2780: 2777: 2776: 2774: 2769: 2766: 2763: 2760: 2757: 2734: 2731: 2728: 2725: 2722: 2719: 2716: 2713: 2710: 2690: 2687: 2684: 2681: 2678: 2675: 2655: 2635: 2630: 2626: 2622: 2619: 2616: 2611: 2607: 2603: 2586: 2583: 2582: 2581: 2570: 2565: 2559: 2554: 2550: 2546: 2543: 2540: 2539: 2536: 2533: 2532: 2529: 2524: 2520: 2516: 2513: 2510: 2509: 2507: 2502: 2499: 2496: 2493: 2490: 2468: 2467: 2456: 2451: 2445: 2442: 2439: 2434: 2430: 2426: 2423: 2422: 2419: 2416: 2415: 2412: 2409: 2406: 2401: 2397: 2393: 2390: 2389: 2387: 2382: 2379: 2376: 2373: 2370: 2345: 2341: 2317: 2298: 2297: 2286: 2281: 2277: 2271: 2267: 2261: 2257: 2253: 2250: 2247: 2244: 2241: 2226: 2225: 2214: 2211: 2208: 2205: 2202: 2197: 2189: 2185: 2181: 2180: 2177: 2174: 2173: 2168: 2164: 2160: 2159: 2157: 2152: 2149: 2126: 2116:observable map 2099: 2096: 2091: 2087: 2081: 2077: 2054: 2050: 2027: 2023: 1998: 1994: 1989: 1985: 1972: 1969: 1957: 1956: 1945: 1940: 1936: 1932: 1929: 1926: 1923: 1909: 1908: 1897: 1894: 1888: 1884: 1880: 1875: 1871: 1832: 1831: 1820: 1815: 1811: 1807: 1802: 1798: 1794: 1791: 1768: 1763: 1759: 1755: 1750: 1746: 1733: 1730: 1729: 1728: 1717: 1714: 1711: 1706: 1702: 1698: 1695: 1658: 1654: 1650: 1647: 1644: 1641: 1637: 1633: 1630: 1619: 1618: 1607: 1602: 1598: 1593: 1590: 1587: 1584: 1572:, is given by 1565: 1564:Time evolution 1562: 1560: 1557: 1532: 1512: 1507: 1503: 1499: 1496: 1474: 1452: 1432: 1429: 1426: 1423: 1420: 1417: 1412: 1408: 1404: 1401: 1390: 1389: 1378: 1375: 1370: 1366: 1362: 1359: 1356: 1353: 1350: 1347: 1344: 1341: 1338: 1333: 1329: 1325: 1322: 1319: 1316: 1291: 1264: 1259: 1233: 1230: 1227: 1224: 1204: 1184: 1164: 1161: 1158: 1155: 1144: 1143: 1132: 1127: 1122: 1117: 1112: 1109: 1087: 1086: 1075: 1070: 1066: 1062: 1059: 1056: 1053: 1048: 1044: 1040: 1037: 1034: 1031: 1015: 1012: 999: 996: 993: 990: 987: 982: 978: 951: 947: 926: 893: 889: 860: 849: 848: 837: 834: 831: 828: 825: 822: 819: 814: 810: 806: 803: 800: 797: 794: 791: 788: 785: 782: 779: 756: 736: 731: 727: 723: 720: 717: 714: 709: 705: 701: 698: 695: 692: 674: 661: 635: 613: 609: 588: 568: 551: 544: 538: 535: 522: 503: 502: 490: 479: 459: 456: 451: 447: 432: 417: 414: 411: 406: 402: 382: 366: 342: 331: 319: 293: 289: 266: 262: 237: 213: 208: 204: 183: 178: 174: 170: 167: 156:Hilbert spaces 141: 137: 114: 110: 90: 87: 71: 68: 26: 9: 6: 4: 3: 2: 9120: 9109: 9106: 9105: 9103: 9088: 9087: 9078: 9077: 9074: 9064: 9061: 9059: 9056: 9054: 9051: 9049: 9046: 9042: 9041:Plasma window 9039: 9038: 9037: 9034: 9032: 9029: 9027: 9024: 9022: 9019: 9017: 9014: 9013: 9011: 9007: 9001: 9000:teleportation 8998: 8996: 8993: 8991: 8988: 8986: 8983: 8981: 8978: 8976: 8973: 8971: 8968: 8966: 8963: 8961: 8958: 8956: 8953: 8951: 8948: 8946: 8943: 8941: 8938: 8936: 8933: 8931: 8928: 8926: 8923: 8921: 8918: 8916: 8913: 8911: 8908: 8906: 8903: 8901: 8898: 8894: 8891: 8890: 8889: 8886: 8884: 8881: 8879: 8876: 8874: 8871: 8869: 8866: 8864: 8861: 8859: 8856: 8854: 8851: 8849: 8846: 8845: 8843: 8841: 8837: 8834: 8830: 8826: 8819: 8814: 8812: 8807: 8805: 8800: 8799: 8796: 8784: 8776: 8775: 8772: 8766: 8763: 8761: 8758: 8756: 8753: 8749: 8746: 8745: 8744: 8741: 8740: 8738: 8734: 8728: 8725: 8723: 8720: 8716: 8713: 8712: 8711: 8708: 8706: 8703: 8701: 8698: 8696: 8693: 8692: 8690: 8686: 8680: 8677: 8675: 8672: 8670: 8667: 8665: 8662: 8660: 8657: 8655: 8652: 8650: 8647: 8645: 8642: 8640: 8637: 8635: 8632: 8630: 8627: 8625: 8622: 8620: 8619:Quantum logic 8617: 8615: 8612: 8610: 8607: 8605: 8602: 8600: 8597: 8595: 8592: 8590: 8587: 8585: 8582: 8578: 8575: 8574: 8573: 8570: 8568: 8565: 8563: 8560: 8558: 8555: 8551: 8548: 8547: 8546: 8543: 8541: 8538: 8536: 8533: 8531: 8528: 8527: 8525: 8523: 8519: 8513: 8510: 8508: 8505: 8503: 8500: 8498: 8495: 8493: 8490: 8488: 8485: 8483: 8480: 8478: 8475: 8473: 8472:Quantum chaos 8470: 8468: 8465: 8463: 8460: 8459: 8457: 8455: 8451: 8445: 8442: 8440: 8439:Stern–Gerlach 8437: 8435: 8432: 8430: 8427: 8425: 8422: 8420: 8417: 8415: 8412: 8410: 8407: 8405: 8402: 8400: 8397: 8395: 8392: 8391: 8389: 8385: 8379: 8376: 8374: 8373:Transactional 8371: 8369: 8366: 8364: 8363:Quantum logic 8361: 8359: 8356: 8354: 8351: 8345: 8342: 8341: 8340: 8337: 8336: 8335: 8332: 8330: 8327: 8325: 8322: 8320: 8317: 8315: 8312: 8310: 8307: 8306: 8304: 8302: 8298: 8292: 8289: 8287: 8284: 8282: 8279: 8277: 8274: 8272: 8269: 8267: 8264: 8262: 8259: 8257: 8254: 8253: 8251: 8247: 8241: 8238: 8236: 8233: 8231: 8228: 8226: 8223: 8221: 8218: 8216: 8213: 8211: 8208: 8207: 8205: 8201: 8193: 8190: 8188: 8185: 8184: 8183: 8182:Wave function 8180: 8178: 8175: 8173: 8170: 8168: 8165: 8163: 8160: 8158: 8157:Superposition 8155: 8153: 8152:Quantum state 8150: 8148: 8145: 8143: 8140: 8138: 8135: 8133: 8130: 8128: 8125: 8123: 8120: 8116: 8113: 8111: 8108: 8106: 8105:Excited state 8103: 8101: 8098: 8097: 8096: 8093: 8091: 8088: 8086: 8083: 8081: 8078: 8076: 8073: 8072: 8070: 8066: 8060: 8057: 8055: 8052: 8050: 8047: 8043: 8040: 8039: 8038: 8035: 8033: 8030: 8029: 8027: 8023: 8019: 8012: 8007: 8005: 8000: 7998: 7993: 7992: 7989: 7977: 7969: 7967: 7959: 7958: 7955: 7949: 7946: 7944: 7941: 7939: 7936: 7934: 7931: 7929: 7925: 7922: 7920: 7916: 7912: 7909: 7908: 7906: 7904: 7898: 7888: 7885: 7883: 7880: 7878: 7875: 7873: 7870: 7869: 7867: 7865: 7861: 7855: 7852: 7850: 7847: 7845: 7844:Spin qubit QC 7842: 7840: 7837: 7836: 7834: 7831: 7827: 7821: 7818: 7816: 7813: 7812: 7810: 7808: 7804: 7798: 7795: 7793: 7790: 7788: 7785: 7783: 7780: 7779: 7777: 7775: 7771: 7768: 7762: 7756: 7753: 7749: 7748: 7744: 7742: 7739: 7737: 7734: 7732: 7729: 7727: 7724: 7722: 7719: 7717: 7714: 7712: 7709: 7708: 7706: 7705: 7703: 7701: 7695: 7689: 7686: 7684: 7681: 7677: 7674: 7673: 7672: 7669: 7665: 7662: 7661: 7660: 7657: 7653: 7652:cluster state 7650: 7649: 7648: 7645: 7643: 7640: 7638: 7635: 7634: 7632: 7630: 7624: 7616: 7612: 7608: 7606: 7602: 7598: 7597: 7596: 7593: 7589: 7586: 7585: 7584: 7581: 7579: 7576: 7574: 7571: 7570: 7568: 7562: 7556: 7553: 7551: 7548: 7546: 7543: 7541: 7538: 7536: 7533: 7532: 7530: 7528: 7522: 7516: 7513: 7511: 7508: 7506: 7503: 7501: 7498: 7496: 7493: 7491: 7488: 7486: 7483: 7481: 7478: 7476: 7473: 7471: 7468: 7466: 7463: 7461: 7460:Deutsch–Jozsa 7458: 7456: 7453: 7451: 7448: 7446: 7443: 7442: 7440: 7438: 7434: 7424: 7421: 7417: 7414: 7412: 7409: 7407: 7404: 7403: 7402: 7399: 7397: 7396:Quantum money 7394: 7392: 7389: 7387: 7384: 7383: 7381: 7379: 7375: 7369: 7366: 7362: 7359: 7358: 7357: 7354: 7350: 7347: 7346: 7345: 7342: 7340: 7337: 7335: 7332: 7330: 7327: 7323: 7320: 7318: 7315: 7314: 7313: 7310: 7309: 7307: 7305:communication 7301: 7295: 7292: 7290: 7287: 7285: 7282: 7280: 7277: 7275: 7272: 7270: 7267: 7265: 7262: 7260: 7257: 7255: 7252: 7250: 7247: 7245: 7242: 7240: 7237: 7235: 7232: 7230: 7227: 7225: 7222: 7220: 7217: 7216: 7214: 7210: 7202: 7199: 7198: 7197: 7194: 7190: 7187: 7186: 7185: 7182: 7180: 7177: 7175: 7172: 7170: 7167: 7163: 7160: 7159: 7158: 7155: 7153: 7150: 7148: 7145: 7144: 7142: 7138: 7134: 7127: 7122: 7120: 7115: 7113: 7108: 7107: 7104: 7096: 7092: 7088: 7084: 7080: 7076: 7071: 7066: 7062: 7057: 7054: 7050: 7049: 7042: 7036: 7028: 7024: 7020: 7016: 7012: 7008: 7003: 6998: 6994: 6990: 6983: 6979: 6969: 6966: 6964: 6961: 6959: 6956: 6955: 6949: 6935: 6932: 6926: 6912: 6893: 6873: 6871: 6867: 6856: 6847: 6843: 6840:This section 6838: 6835: 6831: 6830: 6822: 6806: 6803: 6800: 6770: 6762: 6759: 6756: 6746: 6737: 6730: 6729: 6728: 6726: 6721: 6705: 6675: 6667: 6657: 6648: 6641: 6640: 6639: 6637: 6627: 6625: 6621: 6617: 6613: 6608: 6606: 6602: 6598: 6579: 6573: 6570: 6567: 6562: 6559: 6556: 6550: 6542: 6532: 6527: 6524: 6521: 6508: 6505: 6497: 6494: 6491: 6481: 6476: 6473: 6470: 6457: 6454: 6446: 6436: 6431: 6418: 6411: 6410: 6409: 6406: 6389: 6386: 6378: 6375: 6372: 6362: 6357: 6344: 6337: 6336: 6335: 6319: 6316: 6313: 6284: 6268: 6252: 6223: 6220: 6217: 6188: 6185: 6182: 6167: 6164: Ă—  6163: 6159: 6135: 6112: 6109: 6066: 6063: 6044: 6041: 6033: 6024: 6016:, denoted by 6015: 6000: 5997: 5961: 5959: 5955: 5933: 5929: 5902: 5899: 5889: 5885: 5881: 5876: 5873: 5865: 5858: 5854: 5850: 5825: 5813: 5812: 5796: 5793: 5785: 5781: 5776: 5770: 5766: 5757: 5721: 5717: 5691: 5683: 5679: 5672: 5664: 5660: 5648: 5647: 5643: 5628: 5625: 5590: 5586: 5585: 5584: 5581: 5579: 5575: 5551: 5548: 5543: 5540: 5532: 5527: 5524: 5497: 5496: 5495: 5494:The quantity 5492: 5476: 5473: 5451: 5448:. Similarly, 5447: 5446:concatenation 5429: 5426: 5413: 5397: 5374: 5369: 5366: 5358: 5355: 5352: 5347: 5344: 5336: 5331: 5328: 5323: 5320: 5308: 5307: 5306: 5304: 5300: 5295: 5276: 5273: 5263: 5260: 5252: 5232: 5229: 5226: 5218: 5210: 5207: 5199: 5174: 5173: 5172: 5170: 5166: 5162: 5158: 5154: 5133: 5116: 5104: 5101: 5098: 5092: 5089: 5086: 5067: 5066: 5065: 5049: 5032: 5020: 5015: 5012: 4985: 4968: 4956: 4944: 4942: 4941:classical one 4918: 4910: 4906: 4902: 4891: 4883: 4878: 4875: 4857: 4856: 4855: 4821: 4812: 4784: 4780: 4776: 4763: 4762: 4761: 4758: 4721: 4715: 4712: 4706: 4687: 4675: 4657: 4648: 4635: 4634: 4633: 4591: 4590:operator norm 4587: 4523: 4519: 4504: 4501: 4482: 4474: 4468: 4440: 4412: 4399: 4395: 4391: 4387: 4383: 4373: 4371: 4364:Teleportation 4361: 4359: 4335: 4311: 4310: 4304: 4300: 4296: 4292: 4271: 4266: 4262: 4258: 4253: 4249: 4243: 4238: 4235: 4232: 4228: 4224: 4218: 4205: 4204: 4203: 4181: 4162: 4157: 4154: 4151: 4136: 4133: 4130: 4120: 4110: 4109: 4108: 4060: 4058: 4054: 4049: 4047: 4043: 4024: 4019: 4015: 4008: 4000: 3996: 3990: 3986: 3982: 3976: 3968: 3955: 3954: 3953: 3937: 3932: 3924: 3919: 3914: 3906: 3901: 3887: 3885: 3881: 3862: 3857: 3853: 3844: 3840: 3833: 3828: 3824: 3820: 3814: 3806: 3798: 3793: 3785: 3779: 3766: 3765: 3764: 3747: 3742: 3738: 3729: 3725: 3718: 3713: 3709: 3705: 3701: 3696: 3685: 3681: 3674: 3667: 3655: 3651: 3644: 3638: 3633: 3627: 3615: 3614: 3613: 3588: 3581: 3577: 3558: 3553: 3542: 3538: 3531: 3524: 3512: 3508: 3501: 3495: 3490: 3484: 3476: 3463: 3462: 3461: 3459: 3432: 3428: 3424: 3420: 3416: 3406: 3387: 3383: 3379: 3374: 3370: 3364: 3360: 3356: 3350: 3342: 3332: 3328: 3324: 3318: 3296: 3295: 3294: 3277: 3274: 3271: 3256: 3220: 3216: 3212: 3207: 3203: 3199: 3193: 3185: 3157: 3152: 3148: 3144: 3139: 3135: 3112: 3082: 3073: 3065: 3055: 3051: 3043: 3033: 3025: 3015: 3011: 3004: 2999: 2993: 2990: 2987: 2974: 2973: 2972: 2955: 2949: 2943: 2940: 2935: 2927: 2923: 2915: 2906: 2902: 2895: 2890: 2887: 2880: 2879: 2878: 2861: 2856: 2848: 2844: 2840: 2832: 2828: 2821: 2814: 2805: 2801: 2797: 2789: 2785: 2778: 2772: 2767: 2761: 2748: 2747: 2746: 2729: 2723: 2720: 2714: 2708: 2685: 2679: 2676: 2673: 2628: 2624: 2620: 2617: 2614: 2609: 2605: 2593: 2568: 2563: 2552: 2548: 2541: 2534: 2522: 2518: 2511: 2505: 2500: 2494: 2481: 2480: 2479: 2478:, we can put 2477: 2473: 2454: 2449: 2440: 2437: 2432: 2428: 2417: 2407: 2404: 2399: 2395: 2385: 2380: 2374: 2361: 2360: 2359: 2343: 2329: 2307: 2305: 2284: 2279: 2275: 2269: 2265: 2259: 2255: 2251: 2245: 2231: 2230: 2229: 2209: 2203: 2200: 2195: 2187: 2183: 2175: 2166: 2162: 2155: 2150: 2147: 2140: 2139: 2138: 2117: 2113: 2097: 2094: 2089: 2085: 2079: 2075: 2052: 2048: 2025: 2021: 2013: 1992: 1987: 1983: 1968: 1966: 1962: 1943: 1938: 1934: 1930: 1927: 1921: 1914: 1913: 1912: 1895: 1892: 1886: 1882: 1878: 1873: 1869: 1861: 1860: 1859: 1857: 1853: 1849: 1848:partial trace 1845: 1841: 1837: 1818: 1813: 1809: 1805: 1800: 1796: 1792: 1789: 1782: 1781: 1780: 1766: 1761: 1757: 1753: 1748: 1744: 1715: 1712: 1709: 1704: 1700: 1693: 1686: 1685: 1684: 1682: 1678: 1674: 1652: 1648: 1645: 1642: 1639: 1635: 1631: 1628: 1605: 1600: 1596: 1591: 1588: 1582: 1575: 1574: 1573: 1571: 1556: 1554: 1550: 1546: 1530: 1510: 1505: 1501: 1497: 1494: 1450: 1427: 1421: 1418: 1410: 1406: 1399: 1376: 1368: 1364: 1357: 1348: 1342: 1339: 1331: 1327: 1320: 1317: 1307: 1306: 1305: 1278: 1262: 1247: 1228: 1222: 1215:is finite so 1202: 1182: 1159: 1153: 1130: 1110: 1100: 1099: 1098: 1096: 1092: 1068: 1064: 1057: 1046: 1042: 1035: 1032: 1022: 1021: 1020: 1011: 997: 994: 988: 980: 967: 949: 915: 913: 909: 891: 878: 874: 835: 829: 826: 820: 812: 801: 792: 783: 780: 770: 769: 768: 729: 725: 718: 707: 703: 696: 693: 682: 677: 673: 669: 664: 660: 656: 651: 649: 611: 558: 554: 547: 534: 512: 508: 480: 477: 473: 454: 449: 445: 435: 431: 415: 409: 404: 400: 391: 387: 383: 380: 356: 332: 309: 308: 307: 291: 287: 264: 260: 251: 227: 211: 206: 202: 176: 172: 165: 157: 139: 135: 112: 108: 98: 96: 86: 84: 80: 75: 67: 64: 60: 56: 51: 49: 45: 41: 37: 33: 19: 9084: 9021:Anti-gravity 8965:metamaterial 8893:post-quantum 8888:cryptography 8867: 8556: 8502:Quantum mind 8414:Franck–Hertz 8256:Klein–Gordon 8210:Formulations 8203:Formulations 8132:Interference 8122:Entanglement 8100:Ground state 8095:Energy level 8068:Fundamentals 8032:Introduction 7872:Charge qubit 7797:KLM protocol 7746: 7610: 7600: 7343: 7294:Purification 7224:Eastin–Knill 7060: 7052: 7040: 7035: 6992: 6988: 6982: 6879: 6865: 6863: 6850: 6846:adding to it 6841: 6785: 6724: 6722: 6690: 6635: 6633: 6623: 6612:entanglement 6609: 6604: 6600: 6596: 6594: 6407: 6404: 6269: 6165: 6161: 6157: 6072: 6064: 5964: 5962: 5957: 5953: 5917: 5592: 5588: 5582: 5577: 5573: 5571: 5493: 5449: 5411: 5389: 5302: 5298: 5296: 5293: 5168: 5164: 5160: 5156: 5152: 5150: 4945: 4938: 4804: 4759: 4736: 4521: 4517: 4515: 4394:polarization 4389: 4379: 4367: 4357: 4307: 4302: 4298: 4294: 4290: 4288: 4177: 4066: 4063:Pure channel 4050: 4039: 3888: 3879: 3877: 3762: 3583: 3579: 3575: 3573: 3457: 3430: 3426: 3422: 3418: 3414: 3412: 3404: 3258:Notice that 3257: 3099: 2970: 2876: 2588: 2469: 2330: 2303: 2299: 2227: 2115: 2011: 1974: 1964: 1960: 1958: 1910: 1855: 1851: 1843: 1839: 1835: 1833: 1779:For a state 1735: 1680: 1672: 1620: 1569: 1567: 1391: 1279: 1245: 1195:. We assume 1175:on some set 1145: 1090: 1088: 1017: 916: 911: 907: 876: 875:to those on 872: 850: 675: 671: 667: 662: 658: 654: 652: 556: 549: 542: 540: 510: 506: 504: 471: 433: 429: 389: 379:positive map 99: 92: 78: 76: 73: 52: 35: 29: 9036:Force field 8985:programming 8945:logic clock 8930:information 8905:electronics 8760:EPR paradox 8540:Quantum bus 8409:Double-slit 8387:Experiments 8353:Many-worlds 8291:Schrödinger 8240:Phase space 8230:Schrödinger 8220:Interaction 8177:Uncertainty 8147:Nonlocality 8142:Measurement 8137:Decoherence 8127:Hamiltonian 7903:programming 7882:Phase qubit 7787:Circuit QED 7259:No-deleting 7201:cloud-based 6622:. achieves 5918:A sequence 4382:fiber optic 4306:are called 2472:functionals 2302:integrates 1732:Restriction 1677:Hamiltonian 1095:C*-algebras 8950:logic gate 8848:algorithms 8688:Extensions 8522:Technology 8368:Relational 8319:Copenhagen 8215:Heisenberg 8162:Tunnelling 8025:Background 7943:libquantum 7877:Flux qubit 7782:Cavity QED 7731:Bacon–Shor 7721:stabilizer 7249:No-cloning 6974:References 4334:Karl Kraus 2585:Instrument 1971:Observable 1838:on system 968:, that is, 252:acting on 79:memoryless 8995:simulator 8883:computing 8853:amplifier 8394:Bell test 8249:Equations 8075:Born rule 7849:NV center 7284:Threshold 7264:No-hiding 7229:Gleason's 7070:1106.1445 7027:119250535 7002:1110.3234 6921:Φ 6909:which is 6894:ρ 6888:Φ 6853:June 2008 6804:× 6760:× 6744:Ψ 6655:Ψ 6571:⁡ 6560:⁡ 6525:× 6495:× 6474:× 6376:× 6317:× 6221:× 6186:× 6168:matrices 6106:Ψ 6038:Ψ 6031:Ψ 5994:Ψ 5973:Ψ 5934:α 5890:α 5882:⊗ 5870:Ψ 5859:α 5851:⊗ 5844:^ 5841:Ψ 5831:Δ 5826:α 5809:, we have 5786:α 5771:α 5758:α 5730:∞ 5727:→ 5722:α 5692:⊂ 5684:α 5665:α 5622:Ψ 5601:Ψ 5549:⊗ 5537:Ψ 5525:⊗ 5518:^ 5515:Ψ 5505:Δ 5474:⊗ 5467:^ 5464:Ψ 5423:Ψ 5398:⊗ 5363:Ψ 5359:⊗ 5356:⋯ 5353:⊗ 5341:Ψ 5329:⊗ 5317:Ψ 5270:‖ 5257:Ψ 5253:− 5247:^ 5244:Ψ 5238:‖ 5204:Ψ 5194:^ 5191:Ψ 5182:Δ 5122:→ 5099:∘ 5096:Φ 5093:∘ 5081:^ 5078:Ψ 5038:→ 5009:Ψ 4974:→ 4954:Ψ 4916:‖ 4903:⊗ 4900:Φ 4897:‖ 4872:‖ 4868:Φ 4865:‖ 4842:Φ 4819:∞ 4816:→ 4790:‖ 4777:⊗ 4774:Φ 4771:‖ 4745:Φ 4713:≤ 4710:‖ 4704:‖ 4694:‖ 4679:Λ 4676:− 4673:Φ 4667:‖ 4655:‖ 4652:Λ 4649:− 4646:Φ 4643:‖ 4620:Λ 4600:Φ 4572:Λ 4552:Λ 4532:Φ 4500:coherence 4486:⟩ 4472:⟩ 4444:⟩ 4416:⟩ 4344:Ψ 4320:Ψ 4272:∗ 4229:∑ 4213:Ψ 4190:Ψ 4155:× 4142:→ 4134:× 4118:Ψ 4095:Ψ 4075:Ψ 4057:separable 3987:∑ 3969:∗ 3965:Φ 3938:∗ 3929:Φ 3925:∘ 3920:∗ 3911:Φ 3902:∗ 3898:Φ 3834:ρ 3825:∑ 3815:ρ 3803:Φ 3799:∘ 3790:Φ 3780:ρ 3774:Φ 3719:ρ 3710:∑ 3675:ρ 3668:⋮ 3645:ρ 3624:Φ 3597:Φ 3532:ρ 3525:⋮ 3502:ρ 3485:ρ 3473:Φ 3441:Φ 3361:∑ 3339:Ψ 3329:∑ 3310:~ 3307:Ψ 3275:⊗ 3266:Ψ 3243:Ψ 3182:Ψ 3109:Ψ 3062:Ψ 3044:⋮ 3022:Ψ 2991:⊗ 2982:Ψ 2941:∈ 2916:⋮ 2841:⋅ 2822:ρ 2815:⋮ 2798:⋅ 2779:ρ 2762:ρ 2756:Φ 2721:⊗ 2677:∈ 2674:ρ 2654:Φ 2618:… 2542:ρ 2535:⋮ 2512:ρ 2495:ρ 2489:Ψ 2444:⟩ 2441:ρ 2425:⟨ 2418:⋮ 2411:⟩ 2408:ρ 2392:⟨ 2375:ρ 2369:Ψ 2344:∗ 2340:Ψ 2316:Ψ 2256:∑ 2240:Ψ 2201:∈ 2176:⋮ 2125:Ψ 2076:∑ 1993:∈ 1931:⊗ 1925:→ 1893:ρ 1870:ρ 1806:⊗ 1793:∈ 1790:ρ 1754:⊗ 1705:∗ 1697:→ 1657:ℏ 1640:− 1601:∗ 1592:ρ 1586:→ 1583:ρ 1523:for some 1506:∗ 1419:⊗ 1355:→ 1340:⊗ 1315:Ψ 1121:→ 1108:Ψ 1055:→ 1030:Ψ 981:∗ 977:Φ 950:∗ 946:Φ 925:Φ 892:∗ 888:Φ 859:Φ 833:⟩ 830:ρ 813:∗ 809:Φ 805:⟨ 799:⟩ 793:ρ 787:Φ 778:⟨ 767:given by 755:Φ 716:→ 691:Φ 634:Φ 612:∗ 608:Φ 587:Φ 567:Φ 521:Φ 489:Φ 458:Φ 455:⊗ 413:Φ 410:⊗ 365:Φ 341:Φ 318:Φ 236:Φ 9102:Category 8900:dynamics 8783:Category 8577:Timeline 8329:Ensemble 8309:Bayesian 8271:Majorana 8187:Collapse 8059:Glossary 8042:Timeline 7911:OpenQASM 7887:Transmon 7764:Physical 7564:Quantum 7465:Grover's 7239:Holevo's 7212:Theorems 7162:timeline 7152:NISQ era 6952:See also 6727:of Κ is 4498:). The 1858:system: 1559:Examples 248:between 48:Internet 8990:sensing 8970:network 8955:machine 8925:imaging 8873:circuit 8868:channel 8840:Quantum 8736:Related 8715:History 8454:Science 8286:Rydberg 8037:History 7901:Quantum 7839:Kane QC 7698:Quantum 7626:Quantum 7555:PostBQP 7525:Quantum 7510:Simon's 7303:Quantum 7140:General 7095:2515538 7075:Bibcode 7007:Bibcode 6913:, i.e. 5580:times. 4522:cb-norm 4386:photons 4051:In the 1675:is the 1392:Notice 646:in the 386:ancilla 224:In the 8980:optics 8832:Fields 8429:Popper 7919:IBM QX 7915:Qiskit 7854:NMR QC 7832:-based 7736:Steane 7707:Codes 7505:Shor's 7411:SARG04 7219:Bell's 7093:  7025:  6911:unital 6614:. The 5709:where 5591:is an 5151:where 4586:metric 4289:where 3886:form. 3884:Holevo 3882:or in 3100:where 2594:. Let 2012:effect 1959:where 1621:where 966:unital 851:While 666:) and 428:where 384:If an 9009:Other 8940:logic 8339:Local 8281:Pauli 8261:Dirac 7741:Toric 7184:Qubit 7091:S2CID 7065:arXiv 7023:S2CID 6997:arXiv 4520:, or 4392:) or 377:is a 44:qubit 9086:List 8266:Weyl 7933:Cirq 7924:Quil 7830:Spin 7726:Shor 7406:BB84 7339:LOCC 5963:The 5794:< 5742:and 5390:The 5163:and 4946:Let 4358:pure 3417:and 2877:Let 2112:POVM 1679:and 1671:and 511:CPTP 355:cone 279:and 127:and 100:Let 77:The 34:, a 8858:bus 7747:gnu 7711:CSS 7588:XEB 7550:QMA 7545:QIP 7540:EQP 7535:BQP 7515:VQE 7470:HHL 7274:PBR 7083:doi 7015:doi 6848:. 6568:log 6557:log 6334:is 5822:lim 5754:sup 5750:lim 5223:inf 4888:sup 4661:sup 4368:In 4312:of 4178:By 1850:of 1551:or 964:is 30:In 9104:: 7938:Q# 7089:, 7081:, 7073:, 7021:. 7013:. 7005:. 6993:84 6991:. 6948:. 6872:. 6821:. 6720:. 6607:. 6599:= 6390:0. 5903:0. 5644:if 5491:. 5171:: 4943:. 4428:, 4295:nm 4293:≀ 4182:, 2745:: 2040:. 1967:. 1883:Tr 1842:, 1555:. 1091:CP 879:, 650:: 50:. 8817:e 8810:t 8803:v 8010:e 8003:t 7996:v 7926:– 7917:– 7913:– 7614:2 7611:T 7604:1 7601:T 7125:e 7118:t 7111:v 7098:. 7085:: 7077:: 7067:: 7029:. 7017:: 7009:: 6999:: 6936:I 6933:= 6930:) 6927:I 6924:( 6897:) 6891:( 6855:) 6851:( 6807:2 6801:2 6796:C 6771:, 6768:) 6763:2 6757:2 6752:C 6747:, 6741:( 6738:C 6706:2 6701:C 6676:, 6673:) 6668:2 6663:C 6658:, 6652:( 6649:C 6601:m 6597:n 6580:. 6574:m 6563:n 6551:= 6548:) 6543:n 6538:C 6533:, 6528:m 6522:m 6517:C 6512:( 6509:C 6506:= 6503:) 6498:n 6492:n 6487:C 6482:, 6477:m 6471:m 6466:C 6461:( 6458:C 6455:= 6452:) 6447:n 6442:C 6437:, 6432:m 6427:C 6422:( 6419:C 6387:= 6384:) 6379:n 6373:n 6368:C 6363:, 6358:m 6353:C 6348:( 6345:C 6320:n 6314:n 6309:C 6285:m 6280:C 6253:m 6248:C 6224:n 6218:n 6213:C 6189:n 6183:n 6178:C 6166:n 6162:n 6158:n 6141:B 6136:I 6113:d 6110:i 6083:B 6050:) 6045:d 6042:i 6034:, 6028:( 6025:C 6001:d 5998:i 5958:r 5954:r 5939:} 5930:n 5926:{ 5900:= 5897:) 5886:n 5877:d 5874:i 5866:, 5855:m 5834:( 5797:r 5791:) 5782:m 5777:/ 5767:n 5763:( 5718:m 5696:N 5689:} 5680:m 5676:{ 5673:, 5670:} 5661:n 5657:{ 5629:d 5626:i 5589:r 5578:m 5574:n 5557:) 5552:n 5544:d 5541:i 5533:, 5528:m 5508:( 5477:m 5430:d 5427:i 5412:n 5375:. 5370:d 5367:i 5348:d 5345:i 5337:= 5332:n 5324:d 5321:i 5303:n 5299:n 5277:b 5274:c 5264:d 5261:i 5233:D 5230:, 5227:E 5219:= 5216:) 5211:d 5208:i 5200:, 5185:( 5165:D 5161:E 5157:D 5153:E 5134:2 5128:A 5117:2 5111:B 5105:: 5102:E 5090:D 5087:= 5050:2 5044:A 5033:2 5027:B 5021:: 5016:d 5013:i 4986:1 4980:A 4969:1 4963:B 4957:: 4919:. 4911:n 4907:I 4892:n 4884:= 4879:b 4876:c 4822:. 4813:n 4785:n 4781:I 4722:. 4719:} 4716:1 4707:A 4699:| 4691:) 4688:A 4685:( 4682:) 4670:( 4664:{ 4658:= 4483:1 4479:| 4475:+ 4469:0 4465:| 4441:1 4437:| 4413:0 4409:| 4303:i 4299:K 4291:N 4267:i 4263:K 4259:A 4254:i 4250:K 4244:N 4239:1 4236:= 4233:i 4225:= 4222:) 4219:A 4216:( 4163:. 4158:m 4152:m 4147:C 4137:n 4131:n 4126:C 4121:: 4025:. 4020:i 4016:F 4012:) 4009:A 4006:( 4001:i 3997:R 3991:i 3983:= 3980:) 3977:A 3974:( 3933:2 3915:1 3907:= 3863:. 3858:i 3854:R 3850:) 3845:i 3841:F 3837:( 3829:i 3821:= 3818:) 3812:( 3807:1 3794:2 3786:= 3783:) 3777:( 3748:. 3743:i 3739:R 3735:) 3730:i 3726:F 3722:( 3714:i 3706:= 3702:) 3697:] 3691:) 3686:n 3682:F 3678:( 3661:) 3656:1 3652:F 3648:( 3639:[ 3634:( 3628:2 3610:2 3586:i 3584:R 3580:B 3576:i 3559:. 3554:] 3548:) 3543:n 3539:F 3535:( 3518:) 3513:1 3509:F 3505:( 3496:[ 3491:= 3488:) 3482:( 3477:1 3458:A 3454:1 3431:B 3427:B 3423:A 3419:B 3415:A 3388:i 3384:M 3380:A 3375:i 3371:M 3365:i 3357:= 3354:) 3351:A 3348:( 3343:i 3333:i 3325:= 3322:) 3319:A 3316:( 3281:) 3278:I 3272:f 3269:( 3221:i 3217:M 3213:A 3208:i 3204:M 3200:= 3197:) 3194:A 3191:( 3186:i 3158:2 3153:i 3149:M 3145:= 3140:i 3136:F 3113:i 3083:] 3077:) 3074:A 3071:( 3066:n 3056:n 3052:f 3037:) 3034:A 3031:( 3026:1 3016:1 3012:f 3005:[ 3000:= 2997:) 2994:A 2988:f 2985:( 2956:. 2953:) 2950:X 2947:( 2944:C 2936:] 2928:n 2924:f 2907:1 2903:f 2896:[ 2891:= 2888:f 2862:. 2857:] 2849:n 2845:F 2838:) 2833:n 2829:F 2825:( 2806:1 2802:F 2795:) 2790:1 2786:F 2782:( 2773:[ 2768:= 2765:) 2759:( 2733:) 2730:H 2727:( 2724:L 2718:) 2715:X 2712:( 2709:C 2689:) 2686:H 2683:( 2680:L 2634:} 2629:n 2625:F 2621:, 2615:, 2610:1 2606:F 2602:{ 2569:. 2564:] 2558:) 2553:n 2549:F 2545:( 2528:) 2523:1 2519:F 2515:( 2506:[ 2501:= 2498:) 2492:( 2455:, 2450:] 2438:, 2433:n 2429:F 2405:, 2400:1 2396:F 2386:[ 2381:= 2378:) 2372:( 2304:f 2285:. 2280:i 2276:F 2270:i 2266:f 2260:i 2252:= 2249:) 2246:f 2243:( 2213:) 2210:X 2207:( 2204:C 2196:] 2188:n 2184:f 2167:1 2163:f 2156:[ 2151:= 2148:f 2098:I 2095:= 2090:i 2086:F 2080:i 2053:i 2049:F 2026:i 2022:F 1997:C 1988:i 1984:f 1965:A 1961:A 1944:, 1939:B 1935:I 1928:A 1922:A 1896:. 1887:B 1879:= 1874:A 1856:B 1852:ρ 1844:ρ 1840:A 1836:ρ 1819:, 1814:B 1810:H 1801:A 1797:H 1767:. 1762:B 1758:H 1749:A 1745:H 1716:. 1713:U 1710:A 1701:U 1694:A 1681:t 1673:H 1653:/ 1649:t 1646:H 1643:i 1636:e 1632:= 1629:U 1606:, 1597:U 1589:U 1570:t 1531:x 1511:x 1502:x 1498:= 1495:a 1473:A 1451:a 1431:) 1428:X 1425:( 1422:C 1416:) 1411:B 1407:H 1403:( 1400:L 1377:. 1374:) 1369:A 1365:H 1361:( 1358:L 1352:) 1349:X 1346:( 1343:C 1337:) 1332:B 1328:H 1324:( 1321:L 1318:: 1290:B 1263:n 1258:R 1246:n 1232:) 1229:X 1226:( 1223:C 1203:X 1183:X 1163:) 1160:X 1157:( 1154:C 1131:. 1126:A 1116:B 1111:: 1074:) 1069:A 1065:H 1061:( 1058:L 1052:) 1047:B 1043:H 1039:( 1036:L 1033:: 998:I 995:= 992:) 989:I 986:( 912:A 908:B 877:B 873:A 836:. 827:, 824:) 821:A 818:( 802:= 796:) 790:( 784:, 781:A 735:) 730:B 726:H 722:( 719:L 713:) 708:A 704:H 700:( 697:L 694:: 676:B 672:H 670:( 668:L 663:A 659:H 657:( 655:L 557:B 552:A 550:H 545:A 543:H 478:. 472:n 450:n 446:I 434:n 430:I 416:, 405:n 401:I 390:n 381:. 292:B 288:H 265:A 261:H 212:. 207:A 203:H 182:) 177:A 173:H 169:( 166:L 140:B 136:H 113:A 109:H 20:)

Index

Completely positive trace-preserving
quantum information theory
quantum information
qubit
Internet
completely positive
quantum operation
reduced dynamics
information theory
quantum operation
Hilbert spaces
Schrödinger picture
density matrices
cone
positive map
ancilla
completely positive
Heisenberg picture
Hilbert–Schmidt
unital
C*-algebras
quantum instrument
Frobenius algebra
Frobenius category
Hamiltonian
partial trace
POVM
integrates f against the POVM
functionals
Riesz representation theorem

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