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Quantum state

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5254:. The quantum state of the two slit experiment is a superposition of two single-slit quantum states, one corresponding to the left slit, and the other corresponding to the right slit. In the detector plane, the relative phase of those two single-slit states depends on the difference of the distances from the two slits. Depending on that relative phase, the interference is constructive at some locations and destructive in others, creating the interference pattern. We may say that superposed states are in 1203: 8515: 1832:. The singlet state satisfies the property that if the particles' spins are measured along the same direction then either the spin of the first particle is observed up and the spin of the second particle is observed down, or the first one is observed down and the second one is observed up, both possibilities occurring with equal probability. 5903: 1816: 5241: 1077:
corresponding to that measurement and the value measured. Other aspects of the state may be unknown. Repeating the measurement will not alter the state. In some cases, compatible measurements can further refine the state, causing it to be an eigenstate corresponding to all these measurements. A full
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of independent systems. Statistical mixtures represent the degree of knowledge whilst the uncertainty within quantum mechanics is fundamental. Mathematically, a statistical mixture is not a combination using complex coefficients, but rather a combination using real-valued, positive probabilities of
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The fundamentally statistical or probabilisitic nature of quantum measurements changes the role of quantum states in quantum mechanics compared to classical states in classical mechanics. In classical mechanics, the initial state of one or more bodies is measured; the state evolves according to the
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with another, as its state cannot be described by a pure state. In the first case, there could theoretically be another person who knows the full history of the system, and therefore describe the same system as a pure state; in this case, the density matrix is simply used to represent the limited
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values at each instant of time. For example, the state of a cannon ball would consist of its position and velocity. The state values evolve under equations of motion and thus remain strictly determined. If we know the position of a cannon and the exit velocity of its projectiles, then we can use
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Measurements, macroscopic operations on quantum states, filter the state. Whatever the input quantum state might be, repeated identical measurements give consistent values. For this reason, measurements 'prepare' quantum states for experiments, placing the system in a partially defined state.
1109:. The position wave function is one representation often seen first in introductions to quantum mechanics. The equivalent momentum wave function is another wave function based representation. Representations are analogous to coordinate systems or similar mathematical devices like 1019:
equations of motion; measurements of the final state are compared to predictions. In quantum mechanics, ensembles of identically prepared quantum states evolve according to the equations of motion and many repeated measurements are compared to predicted probability distributions.
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knowledge of a quantum state. In the second case, however, the existence of quantum entanglement theoretically prevents the existence of complete knowledge about the subsystem, and it's impossible for any person to describe the subsystem of an entangled pair as a pure state.
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Subsequent measurements may either further prepare the system – these are compatible measurements – or it may alter the state, redefining it – these are called incompatible or complementary measurements. For example, we may measure the momentum of a state along the
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of the operator correspond to the possible values of the observable. For example, it is possible to observe a particle with a momentum of 1 kg⋅m/s if and only if one of the eigenvalues of the momentum operator is 1 kg⋅m/s. The corresponding
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axis any number of times and get the same result, but if we measure the position after once measuring the momentum, subsequent measurements of momentum are changed. The quantum state appears unavoidably altered by incompatible measurements. This is known as the
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degree of freedom of a quantum system. Most particles possess a kind of intrinsic angular momentum that does not appear at all in classical mechanics and arises from Dirac's relativistic generalization of the theory. Mathematically it is described with
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i.e. separated by a zero delay. One can think of it as stopping the time, then making the two measurements one after the other, then resuming the time. Thus, the measurements occurred at the same time, but it is still possible to tell which was
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The coefficient that corresponds to a particular state in the linear combination is a complex number, thus allowing interference effects between states. The coefficients are time dependent. How a quantum state changes in time is governed by the
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Dirac (1958), p. 20: "The bra vectors, as they have been here introduced, are quite a different kind of vector from the kets, and so far there is no connexion between them except for the existence of a scalar product of a bra and a
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Another feature of quantum states becomes relevant if we consider a physical system that consists of multiple subsystems; for example, an experiment with two particles rather than one. Quantum physics allows for certain states, called
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particles are identical, but some of them are, then the function must be (anti)symmetrized separately over the variables corresponding to each group of identical variables, according to its statistics (bosonic or fermionic).
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of a quantum state. The result is a prediction for the system represented by the state. Knowledge of the quantum state, and the rules for the system's evolution in time, exhausts all that can be known about a quantum system.
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for operators corresponding to measurements can readily be expressed as pure states; they must be combined with statistical weights matching experimental preparation to compute the expected probability distribution.
5620: 1660: 4816: 4221: 6916: 2284: 1145:. Historically, definitions of quantum states used wavefunctions before the more formal methods were developed. The wave function is a complex-valued function of any complete set of commuting or compatible 2847:
SU(2) are used to describe this additional freedom. For a given particle, the choice of representation (and hence the range of possible values of the spin observable) is specified by a non-negative number
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A mixed quantum state corresponds to a probabilistic mixture of pure states; however, different distributions of pure states can generate equivalent (i.e., physically indistinguishable) mixed states. A
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Historical, educational, and application-focused problems typically feature wave functions; modern professional physics uses the abstract vector states. In both categories, quantum states divide into
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twice in the same run of the experiment, the measurements being directly consecutive in time, then they will produce the same results. This has some strange consequences, however, as follows.
3725: 6343: 2004: 1389: 4483: 5898:{\displaystyle \langle A\rangle =\sum _{s}p_{s}\langle \psi _{s}|A|\psi _{s}\rangle =\sum _{s}\sum _{i}p_{s}a_{i}|\langle \alpha _{i}|\psi _{s}\rangle |^{2}=\operatorname {tr} (\rho A)} 4478: 4148: 2964: 4284: 6688: 6499: 6469: 6411: 4251: 3927: 1124:', avoiding any particular representation. This allows many elegant concepts of quantum mechanics to be expressed and to be applied even in cases where no classical analog exists. 6545: 5938: 3015: 5669: 6030: 5356: 4600: 4440: 4726: 3822: 3587: 3406: 1320: 4754: 2425: 6716: 6573: 6439: 6381: 4410: 4279: 4071: 3981: 3866: 3682: 3546: 3434: 2735: 2699: 2671: 2631: 2599: 2533: 1003:
The process of describing a quantum system with quantum mechanics begins with identifying a set of variables defining the quantum state of the system. The set will contain
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Mixed states arise in quantum mechanics in two different situations: first, when the preparation of the system is not fully known, and thus one must deal with a
5236:{\displaystyle e^{i\theta _{\alpha }}\left(A_{\alpha }|\alpha \rangle +{\sqrt {1-A_{\alpha }^{2}}}e^{i\theta _{\beta }-i\theta _{\alpha }}|\beta \rangle \right)} 3304:-particle function must either be symmetrized (in the bosonic case) or anti-symmetrized (in the fermionic case) with respect to the particle numbers. If not all 7960: 6050: 5995: 5538: 5488: 4680: 4660: 4640: 4620: 2805: 2445: 2387: 2367: 2310: 1499: 1052: 383: 6932:
is 1, as it is for the standard definition given in this section. Occasionally a density matrix will be normalized differently, in which case the criterion is
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would consist of complex values over the detection region and, when squared, only predict the probability distribution of electron counts across the detector.
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is a statistical mean of measured values of the observable. It is this mean, and the distribution of probabilities, that is predicted by physical theories.
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Similarly, quantum states consist of sets of dynamical variables that evolve under equations of motion. However, the values derived from quantum states are
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to describe the behavior of many similar particles by giving a probability distribution (or ensemble) of states that these particles can be found in.
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can be formed into pure states. Experiments rarely produce pure states. Therefore statistical mixtures of solutions must be compared to experiments.
2493:. In order to make such calculations flow smoothly, and to make it unnecessary (in some contexts) to fully understand the underlying linear algebra, 8495: 7809: 7147: 591: 135: 6935: 3439: 1879:: a state that implies a narrow spread of possible outcomes for one experiment necessarily implies a wide spread of possible outcomes for another. 991:
for the outcomes for a system. These constraints alter the nature of quantum dynamic variables. For example, the quantum state of an electron in a
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The rules for measurement in quantum mechanics are particularly simple to state in terms of density matrices. For example, the ensemble average (
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is usually formulated in terms of the Schrödinger picture, the Heisenberg picture is often preferred in a relativistic context, that is, for
2064:; thus the state has changed, unless the system was already in that eigenstate. This expresses a kind of logical consistency: If we measure 8036: 7093: 3951:
of the observable which corresponds to measuring position. If these eigenstates are nondegenerate (for example, if the system is a single,
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pure states, treating them on the same footing. Moreover, a mixed quantum state on a given quantum system described by a Hilbert space
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particles, each potentially with spin, is described by a complex-valued function with four variables per particle, corresponding to 3
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The overall phase factor in front has no physical effect. Only the relative phase affects the physical nature of the superposition.
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notation, where vectors are usually lower-case Latin letters, and it is clear from the context that they are indeed vectors.
1011:. Subsequent measurement of the state produces a sample from a probability distribution predicted by the quantum mechanical 8440: 8217: 8139: 7922: 7792: 7272: 5491: 5300: 1883: 606: 344: 244: 8174: 3596: 2748: 2286:.) Conceptually (and mathematically), the two approaches are equivalent; choosing one of them is a matter of convention. 1283: 359: 8108: 8103: 8074: 7787: 2642: 1068: 542: 537: 508: 140: 8149: 321: 311: 8242: 6150: 6093: 6085: 5688:
is equal to 1 if the state is pure, and less than 1 if the state is mixed. Another, equivalent, criterion is that the
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describing the measurement. Probability distributions for different measurements exhibit tradeoffs exemplified by the
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is physically inconsequential (as long as the state is considered by itself). If a vector in a complex Hilbert space
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can be complex numbers; their relative amplitude and relative phase will influence the resulting quantum state.
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for the outcome, and the form that this distribution takes is completely determined by the quantum state and the
527: 488: 416: 339: 199: 2555:" can be replaced by any other symbols, letters, numbers, or even words). This can be contrasted with the usual 1882:
Statistical mixtures of states are a different type of linear combination. A statistical mixture of states is a
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spatial coordinates of an electron. Preparing a system by measuring the complete set of compatible produces a
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Quantum states may be defined differently for different kinds of systems or problems. Two broad categories are
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For a discussion of purifications of mixed quantum states, see Chapter 2 of John Preskill's lecture notes for
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Expansions of this sort play an important role in measurement in quantum mechanics. In particular, if the
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Lev Landau (1927). "Das DĂ€mpfungsproblem in der Wellenmechanik (The Damping Problem in Wave Mechanics)".
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A simple criterion for checking whether a density matrix is describing a pure or mixed state is that the
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The expression used to denote a state vector (which corresponds to a pure quantum state) takes the form
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can be obtained from another vector by multiplying by some non-zero complex number, the two vectors in
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States can be formulated in terms of observables, rather than as vectors in a vector space. These are
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variable (for the spin) is added to the usual three continuous variables (for the position in space).
2155:) that allow us to distinguish between quantum theory and alternative classical (non-quantum) models. 1293: 8445: 8374: 8319: 8049: 7872: 7593: 7230: 6868: 5359: 5311: 5307: 5296: 4731: 4567:{\displaystyle \int _{K}|\phi (\mathbf {r} ,t)|^{2}\,\mathrm {d} ^{3}\mathbf {r} \geq 1-\varepsilon } 2399: 2390: 2346: 2294: 2148: 1836: 1726: 1677: 956: 952: 815: 571: 483: 209: 7354: 6693: 6550: 6416: 6358: 4387: 4256: 4048: 3958: 3890:. (The normalization condition above mandates that the total sum of probabilities is equal to one.) 3843: 3659: 3523: 3411: 2712: 2676: 2648: 2608: 2576: 2510: 2503:. Although the details of this are beyond the scope of this article, some consequences of this are: 2173:. (This approach was taken in the later part of the discussion above, with time-varying observables 1286:, there are two possible results: up or down. A pure state here is represented by a two-dimensional 8430: 8399: 8344: 8324: 8232: 8189: 8044: 7970: 7897: 7887: 7799: 7722: 5689: 5259: 4074: 3289: 3005: 2995: 2882: 2335: 2321: 1206: 1110: 1008: 968: 670: 478: 396: 224: 204: 156: 4083: 3932: 2199:. (This approach was taken in the earlier part of the discussion above, with a time-varying state 8359: 8257: 7965: 7912: 7804: 7609: 7254: 7220: 6155: 6135: 4821: 3368: 2170: 1860: 1569: 1527: 1146: 1012: 391: 316: 249: 161: 8490: 5497: 4848: 4354:{\displaystyle |\psi \rangle =\int d^{3}\mathbf {r} \,\psi (\mathbf {r} )|\mathbf {r} \rangle .} 3255: 2342:
in the Hilbert space, because the unit sphere is defined as the set of all vectors with norm 1.
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equations containing the force of gravity to predict the trajectory of a cannon ball precisely.
7302: 5273:. The resulting superposition ends up oscillating back and forth between two different states. 1944: 1890: 1686: 1394: 8500: 8409: 8379: 8307: 8270: 8265: 8247: 8212: 8202: 7917: 7882: 7865: 7768: 7694: 7686: 7663: 7522: 7490: 7489:. The theoretical minimum / Leonard Susskind and George Hrabovsky. New York, NY: Basic Books. 7465: 7410: 7323: 7246: 7191: 7181: 7153: 7123: 7098: 7044: 6860:{\displaystyle \langle \mathbf {r} |\mathbf {r} '\rangle =\delta (\mathbf {r} '-\mathbf {r} )} 6140: 5977:" denotes trace. It is important to note that two types of averaging are occurring, one (over 3894: 3590: 3335: 3224: 2706: 2634: 2290: 2152: 1424: 906: 825: 800: 740: 735: 635: 601: 581: 179: 38: 7541: 3105:{\displaystyle |\psi (\mathbf {r} _{1},\,m_{1};\;\dots ;\;\mathbf {r} _{N},\,m_{N})\rangle .} 1458: 8227: 8222: 8079: 7975: 7601: 7238: 7173: 6160: 5310:
of possible preparations; and second, when one wants to describe a physical system which is
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observables. For example, we cannot prepare a state such that both the position measurement
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A mixed state for electron spins, in the density-matrix formulation, has the structure of a
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Note that this criterion works when the density matrix is normalized so that the trace of
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The same physical quantum state can be expressed mathematically in different ways called
971:. A classical dynamical state consists of a set of dynamical variables with well-defined 7597: 7234: 27:
Mathematical entity to describe the probability of each possible measurement on a system
8435: 8404: 8394: 8016: 8006: 7840: 7652: 7398: 7326:(1927). Über den anschaulichen Inhalt der quantentheoretischen Kinematik und Mechanik, 6035: 5980: 5523: 5473: 5282: 4665: 4645: 4625: 4605: 4602:. The integral represents the probability that a particle is found in a bounded region 3952: 3517: 3009: 2983: 2430: 2372: 2352: 2330:, as follows. Any given system is identified with some finite- or infinite-dimensional 2327: 1848: 1844: 1537: 1516: 1452: 1287: 1265: 1202: 1037: 944: 921: 790: 750: 730: 700: 680: 630: 596: 446: 436: 229: 7276: 4374:
Though closely related, pure states are not the same as bound states belonging to the
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The density matrix describing a mixed state is defined to be an operator of the form
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For a discussion of conceptual aspects and a comparison with classical states, see:
7449:. Course of Theoretical Physics. Vol. 3 (2nd ed.). London: Pergamon Press. 7258: 5318:
Mixed states inevitably arise from pure states when, for a composite quantum system
2633:, which corresponds to the same physical quantum state. Technically, the bra is the 8237: 7850: 7845: 7682: 7562: 7402: 6787:{\textstyle \int d^{3}\mathbf {r} '\,\langle \mathbf {r} |\mathbf {r} '\rangle =1,} 6125: 6115: 5093:{\displaystyle |c_{\alpha }|^{2}+|c_{\beta }|^{2}=A_{\alpha }^{2}+A_{\beta }^{2}=1} 2969: 2868: 1509: 1121: 972: 840: 835: 770: 755: 720: 214: 5454:
be described with a single ket vector. Instead, it is described by its associated
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is used, properly speaking, a point the projective Hilbert space corresponds to a
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represent quantum states, particularly when they are functions of position or of
7710: 5997:) being the usual expected value of the observable when the quantum is in state 5490:
can be always represented as the partial trace of a pure quantum state (called a
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if it remains localized in a bounded region of space for all times. A pure state
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On the other hand, a system in a superposition of multiple different eigenstates
8275: 7732: 7353:(1927/1928). The quantum postulate and the recent development of atomic theory, 7088: 6145: 5291:
is a state which can be described by a single ket vector, as described above. A
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Another example of the importance of relative phase in quantum superposition is
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in the same run of the experiment, the system will transfer to an eigenstate of
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is chosen for the Hilbert space of a system, then any ket can be expanded as a
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was fixed once at the beginning of the experiment. This approach is called the
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As a consequence, the quantum state of a particle with spin is described by a
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after the first measurement, and we will generally notice that the results of
1968:. Unlike the linear combination case each system is in a definite eigenstate. 1541: 1532: 1004: 795: 765: 685: 660: 655: 640: 7250: 7195: 6989:{\displaystyle \operatorname {Tr} (\rho ^{2})=(\operatorname {Tr} \rho )^{2}} 4032:{\displaystyle \psi (\mathbf {r} )\equiv \langle \mathbf {r} |\psi \rangle .} 3214:{\displaystyle \{-S_{\nu },\,-S_{\nu }+1,\,\ldots ,\,S_{\nu }-1,\,S_{\nu }\}} 2111:, all runs of the experiment will yield the same result. If we measure first 112:{\displaystyle i\hbar {\frac {d}{dt}}|\Psi \rangle ={\hat {H}}|\Psi \rangle } 8129: 7825: 7518: 4378:
of an observable with no quantum uncertainty. A particle is said to be in a
3840:) of an observable, and that observable is measured on the normalized state 2872: 2844: 2702: 1941:
represents the probability of a randomly selected system being in the state
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is a mathematical entity that embodies the knowledge of a quantum system.
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Decomposition of spectrum (functional analysis) § Quantum mechanics
2645:. In a finite-dimensional space with a chosen orthonormal basis, writing 1523: 1230: 1226: 1213:
Numerical or analytic solutions in quantum mechanics can be expressed as
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The concept of quantum states, in particular the content of the section
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The density matrix can be thought of as a way of using the one-particle
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is associated with a complex-valued function of three-dimensional space
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One can take the observables to be dependent on time, while the state
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can be found at different positions with corresponding probabilities.
4811:{\displaystyle c_{\alpha }|\alpha \rangle +c_{\beta }|\beta \rangle } 3331: 3320: 2836: 2819: 2151:. These entangled states lead to experimentally testable properties ( 2052:
Moreover, in contrast to classical mechanics, it is unavoidable that
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in general have quantum uncertainty for the given observable. Using
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Lectures on Quantum Theory: Mathematical and Structural Foundations
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above, is covered in most standard textbooks on quantum mechanics.
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Kirkpatrick, K. A. (February 2006). "The Schrödinger-HJW Theorem".
5269:, where the relative phase of two states varies in time due to the 2744:) are written so as to look like a bra and ket next to each other: 2289:
Both viewpoints are used in quantum theory. While non-relativistic
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classifies the multitude of ways to write a given mixed state as a
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describing quantum systems using position or momentum variables and
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performing a measurement on the system generally changes its state
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and incoherent states. Categories with special properties include
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Mastering Quantum Mechanics: Essentials, Theory, and Applications
6346:: "to define the scalar products as being between bras and kets." 5692:
is 0 for a pure state, and strictly positive for a mixed state.
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for the electron of a hydrogen atom in different quantum states.
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passing through the origin of the Hilbert space, rather than a
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are eigenkets and eigenvalues, respectively, for the operator
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Cohen-Tannoudji, Claude; Diu, Bernard; Laloë, Franck (1977).
6092:, or sometimes other classes of algebras of observables. See 3868:, then the probability that the result of the measurement is 3500:{\displaystyle |\psi \rangle =\sum _{i}c_{i}|{k_{i}}\rangle } 7485:
Susskind, Leonard; Friedman, Art; Susskind, Leonard (2014).
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are elements of the same Hilbert space. A particle in state
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As a tool for physics, quantum states grew out of states in
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For a more detailed coverage of mathematical aspects, see:
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When symmetrization or anti-symmetrization is unnecessary,
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There is no state that is simultaneously an eigenstate for
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Mathematical formulation of quantum mechanics § Spin
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is performed on a quantum system, the theory gives only a
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invented a notation to describe quantum states, known as
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of those basis elements. Symbolically, given basis kets
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Quantum physics is most commonly formulated in terms of
7122:. Vol. 2. Courier Dover Publications. p. 87. 5389:
is inaccessible to the observer. The state of the part
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of one-particle spaces, to which we will return later.
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Calculations in quantum mechanics make frequent use of
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are two kets corresponding to quantum states, the ket
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1. Thus the set of all pure states corresponds to the
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Operator Algebras and Quantum Statistical Mechanics 1
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Quantum mechanical measurements influence one another
1977: 1947: 1920: 1893: 1735: 1689: 1578: 1481: 1461: 1427: 1397: 1328: 1296: 1155: 1040: 50: 3338:
and can't be described with Schrödinger mechanics).
8471: 8423: 8256: 8188: 8122: 8035: 7999: 7953: 7818: 7775: 7393: 7391: 7120:
A History of the Theories of Aether and Electricity
5633:is the fraction of the ensemble in each pure state 3642:{\displaystyle c_{i}=\langle {k_{i}}|\psi \rangle } 2786:{\displaystyle \langle \psi _{1}|\psi _{2}\rangle } 1087: 7651: 7385:, 4th edition, Oxford University Press, Oxford UK. 7180:. Lecture Notes in Physics. Springer. p. 15. 6988: 6910: 6859: 6786: 6710: 6682: 6567: 6539: 6493: 6463: 6433: 6405: 6375: 6044: 6024: 5989: 5959: 5932: 5897: 5699:) of a measurement corresponding to an observable 5663: 5614: 5532: 5512: 5482: 5439: 5408: 5381: 5350: 5235: 5092: 4976: 4864: 4837: 4810: 4748: 4720: 4674: 4654: 4642:. If the probability remains arbitrarily close to 4634: 4614: 4594: 4566: 4472: 4434: 4404: 4353: 4273: 4245: 4215: 4142: 4094: 4065: 4031: 3975: 3943: 3921: 3860: 3816: 3778:{\displaystyle \sum _{i}\left|c_{i}\right|^{2}=1.} 3777: 3719: 3676: 3641: 3581: 3540: 3499: 3428: 3400: 3277: 3240: 3213: 3104: 2958: 2785: 2729: 2693: 2665: 2625: 2593: 2547: 2527: 2439: 2419: 2381: 2361: 2278: 2105:at the experiment's beginning. If we measure only 2099:. Suppose that the system is in an eigenstate of 2093:corresponds to a measurement earlier in time than 1998: 1960: 1933: 1906: 1810: 1701: 1654: 1487: 1467: 1443: 1413: 1383: 1314: 1173: 1046: 111: 7639: 7443:Quantum Mechanics — Non-Relativistic Theory 7341:(1983), Princeton University Press, Princeton NJ. 4818:is also a quantum state of the same system. Both 4223:In terms of the continuous set of position basis 1822:of joint spin states for two particles with spin 1237:, the relevant pure states are identified by the 1185:. More common, incomplete preparation produces a 1117: 928: 7428: 7426: 2056:. More precisely: After measuring an observable 7374: 7372: 7370: 3899:, which is the basis consisting of eigenstates 1221:, are labeled with quantized values, typically 1073:The quantum state after a measurement is in an 6333:now appears as a complete bracket expression." 6190:To avoid misunderstandings: Here we mean that 3720:{\displaystyle \langle \psi |\psi \rangle =1,} 3300:(particles with half-integer spin). The above 2316:Pure states as rays in a complex Hilbert space 7753: 6383:is a superposition of different basis states 3727:and for orthonormal basis this translates to 2311:Mathematical formulation of quantum mechanics 1999:{\displaystyle {\langle A\rangle }_{\sigma }} 1835:A pure quantum state can be represented by a 1800: 1764: 1384:{\displaystyle |\alpha |^{2}+|\beta |^{2}=1,} 878: 8: 7487:Quantum mechanics: the theoretical minimum; 7460:Blanchard, Philippe; BrĂŒning, Erwin (2015). 6896: 6878: 6824: 6801: 6772: 6749: 6705: 6677: 6562: 6488: 6458: 6428: 6400: 6370: 6319:Dirac (1958), p. 19: "A scalar product 6072:, the concept of mixture was put forward by 6019: 5927: 5859: 5831: 5780: 5744: 5718: 5712: 5655: 5594: 5591: 5225: 5150: 4805: 4781: 4743: 4715: 4399: 4345: 4296: 4268: 4240: 4073:. Similarly to the discrete case above, the 4060: 4023: 4007: 3970: 3916: 3855: 3811: 3705: 3691: 3671: 3636: 3613: 3576: 3535: 3494: 3451: 3423: 3395: 3208: 3128: 3096: 2953: 2905: 2839:. In non-relativistic quantum mechanics the 2780: 2752: 2724: 2701:is a row vector; to obtain it just take the 2680: 2660: 2612: 2588: 2522: 2273: 2223: 1986: 1980: 1680:of quantum states is again a quantum state. 1646: 1596: 1120:) the theory develops in terms of abstract ' 106: 80: 7716:For a discussion of geometric aspects see: 5466:. Density matrices can describe both mixed 3285:for a particle that does not exhibit spin. 2334:. The pure states correspond to vectors of 1540:that acts on the states of the system. The 909:specifies the construction, evolution, and 7760: 7746: 7738: 7034: 7032: 4696:As mentioned above, quantum states may be 3066: 3059: 2322:Wigner's theorem § Rays and ray space 2159:Schrödinger picture vs. Heisenberg picture 1082:. Any state that is not pure is called a 1078:set of compatible measurements produces a 885: 871: 29: 7224: 7030: 7028: 7026: 7024: 7022: 7020: 7018: 7016: 7014: 7012: 6980: 6952: 6937: 6891: 6886: 6881: 6876: 6849: 6837: 6815: 6809: 6804: 6799: 6763: 6757: 6752: 6748: 6739: 6732: 6723: 6697: 6695: 6672: 6667: 6665: 6554: 6552: 6508: 6506: 6483: 6478: 6476: 6453: 6448: 6446: 6420: 6418: 6395: 6390: 6388: 6362: 6360: 6037: 6013: 6004: 6002: 5982: 5951: 5945: 5921: 5912: 5910: 5868: 5863: 5853: 5844: 5838: 5826: 5820: 5810: 5800: 5790: 5774: 5765: 5757: 5751: 5738: 5728: 5710: 5649: 5640: 5638: 5607: 5601: 5585: 5576: 5570: 5560: 5548: 5525: 5499: 5475: 5431: 5425: 5400: 5394: 5373: 5367: 5342: 5329: 5323: 5217: 5209: 5193: 5185: 5173: 5168: 5156: 5142: 5136: 5119: 5111: 5105: 5100:and extracting the common factors gives: 5078: 5073: 5060: 5055: 5042: 5037: 5030: 5021: 5012: 5007: 5000: 4991: 4989: 4966: 4958: 4948: 4935: 4917: 4909: 4899: 4886: 4880: 4856: 4850: 4829: 4823: 4797: 4791: 4773: 4767: 4761: 4735: 4733: 4707: 4705: 4667: 4647: 4627: 4607: 4588: 4587: 4579: 4547: 4541: 4536: 4534: 4528: 4523: 4508: 4497: 4491: 4485: 4473:{\displaystyle K\subset \mathbb {R} ^{3}} 4464: 4460: 4459: 4450: 4421: 4391: 4389: 4340: 4335: 4327: 4320: 4315: 4309: 4288: 4286: 4260: 4258: 4235: 4230: 4228: 4201: 4196: 4187: 4176: 4175: 4170: 4164: 4155: 4143:{\displaystyle |\psi (\mathbf {r} )|^{2}} 4134: 4129: 4120: 4109: 4107: 4087: 4085: 4052: 4050: 4015: 4010: 3996: 3988: 3962: 3960: 3936: 3934: 3911: 3906: 3904: 3847: 3845: 3804: 3799: 3794: 3792: 3763: 3753: 3738: 3732: 3697: 3689: 3663: 3661: 3628: 3621: 3616: 3604: 3598: 3569: 3564: 3559: 3557: 3527: 3525: 3487: 3482: 3477: 3471: 3461: 3443: 3441: 3415: 3413: 3388: 3383: 3378: 3376: 3263: 3257: 3232: 3226: 3202: 3197: 3182: 3177: 3170: 3155: 3147: 3138: 3126: 3087: 3082: 3073: 3068: 3050: 3045: 3036: 3031: 3019: 3017: 2959:{\displaystyle \{-S,-S+1,\ldots ,S-1,S\}} 2903: 2774: 2765: 2759: 2750: 2716: 2714: 2686: 2678: 2652: 2650: 2618: 2610: 2580: 2578: 2540: 2514: 2512: 2432: 2403: 2401: 2374: 2354: 2267: 2258: 2243: 2233: 2206: 2204: 2060:, the system will be in an eigenstate of 1990: 1979: 1976: 1952: 1946: 1925: 1919: 1898: 1892: 1799: 1798: 1763: 1762: 1750: 1734: 1688: 1640: 1631: 1616: 1606: 1579: 1577: 1480: 1460: 1436: 1428: 1426: 1406: 1398: 1396: 1366: 1361: 1352: 1343: 1338: 1329: 1327: 1295: 1154: 1039: 98: 87: 86: 72: 57: 49: 7729:. Cambridge: Cambridge University Press. 7149:Quantum Computing: A Gentle Introduction 7043:. North Holland, John Wiley & Sons. 4080:of the particle being found at position 3893:A particularly important example is the 2990:Many-body states and particle statistics 2601:is uniquely associated with a so-called 1847:, while mixed states are represented by 1717:1. A more complicated case is given (in 1502:state that pure states, at a given time 1201: 7409:(2nd, illustrated ed.). Springer. 7178:Statistical Structure of Quantum Theory 7083: 7081: 7079: 7077: 7075: 7008: 6660:In the continuous case, the basis kets 6183: 5520:for a sufficiently large Hilbert space 4984:and defining the norm of the state as: 4662:then the particle is said to remain in 2978:. Equivalently, it is represented by a 54: 37: 7572:. London: Heinemann. pp. 284–302. 7544:Density matrix theory and applications 6086:positive normalized linear functionals 3652:One property worth noting is that the 1572:of eigenstates can be represented as: 1322:, with a length of one; that is, with 963:From the states of classical mechanics 6683:{\displaystyle |\mathbf {r} \rangle } 6494:{\displaystyle |\mathbf {r} \rangle } 6464:{\displaystyle |\mathbf {r} \rangle } 6406:{\displaystyle |\mathbf {r} \rangle } 6247:For concreteness' sake, suppose that 6065:that the quantum is in those states. 4246:{\displaystyle |\mathbf {r} \rangle } 3922:{\displaystyle |\mathbf {r} \rangle } 3589:. If the basis kets are chosen to be 3296:(particles with integer spin) versus 2972:-valued wave function with values in 1863:of pure states. Before a particular 1225:. For example, when dealing with the 1005:compatible and incompatible variables 7: 7118:Whittaker, Sir Edmund (1989-01-01). 7094:Quantum Theory: Concepts and Methods 6718:): They are normalized according to 6690:are not unit kets (unlike the state 6540:{\displaystyle \mathbf {r} =(x,y,z)} 6212:are measured in the same state, but 5933:{\displaystyle |\alpha _{i}\rangle } 5246:One example of superposition is the 4875:Writing the superposed state using 3355:Basis states of one-particle systems 2830:and, at quantum scale, behaves as a 2637:of the ket. It is an element of the 1713:and positive semi-definite, and has 1526:) is associated with a mathematical 1149:. For example, one set could be the 7563:"Remarks on the mind-body question" 7383:The Principles of Quantum Mechanics 7146:; Polak, Wolfgang H. (2011-03-04). 5664:{\displaystyle |\psi _{s}\rangle .} 2562:Dirac defined two kinds of vector, 2389:are said to correspond to the same 7618:English translation reprinted in: 6902: 6216:in the same run of the experiment. 6098:Gelfand–Naimark–Segal construction 6025:{\displaystyle |\psi _{s}\rangle } 5351:{\displaystyle H_{1}\otimes H_{2}} 5250:, in which superposition leads to 4537: 3323:(quanta of light) are bosons with 2264: 2211: 1949: 1895: 1637: 1584: 1015:corresponding to the measurement. 417:Sum-over-histories (path integral) 103: 77: 33:Part of a series of articles about 25: 6501:is located precisely at position 6131:Introduction to quantum mechanics 6121:Greenberger–Horne–Zeilinger state 6056:) average with the probabilities 4595:{\displaystyle t\in \mathbb {R} } 4435:{\displaystyle \varepsilon >0} 3000:The quantum state of a system of 1191:Schrödinger's equations of motion 1116:In formal quantum mechanics (see 8514: 8513: 6892: 6882: 6850: 6838: 6816: 6805: 6764: 6753: 6740: 6673: 6617:" (the left side corresponds to 6509: 6484: 6454: 6396: 4721:{\displaystyle |\alpha \rangle } 4548: 4509: 4341: 4328: 4316: 4236: 4188: 4171: 4150:and the normalized states have 4121: 4088: 4011: 3997: 3937: 3912: 3817:{\displaystyle |{k_{i}}\rangle } 3582:{\displaystyle |{k_{i}}\rangle } 3401:{\displaystyle |{k_{i}}\rangle } 3069: 3032: 2982:of four variables: one discrete 2641:, and related to the ket by the 2404: 1855:that act on Hilbert spaces. The 1315:{\displaystyle (\alpha ,\beta )} 1217:. These solution states, called 1093:The eigenstate solutions to the 1029:Measurement in quantum mechanics 940: 7622:Collected papers of L.D. Landau 7462:Mathematical Methods in Physics 7407:Quantum Mechanics: Fundamentals 7273:"Statistical Mixture of States" 5494:) on a larger bipartite system 4749:{\displaystyle |\beta \rangle } 2420:{\displaystyle \mathbf {P} (H)} 2047:Heisenberg uncertainty relation 1853:positive semidefinite operators 1500:postulates of quantum mechanics 1248:angular momentum quantum number 936: 8463:Relativistic quantum mechanics 7733:second, revised edition (2017) 7339:Quantum Theory and Measurement 7212:Foundations of Physics Letters 7097:. Kluwer Academic Publishers. 6977: 6964: 6958: 6945: 6887: 6854: 6833: 6810: 6758: 6711:{\displaystyle |\psi \rangle } 6698: 6668: 6568:{\displaystyle |\psi \rangle } 6555: 6534: 6516: 6479: 6449: 6434:{\displaystyle |\psi \rangle } 6421: 6391: 6376:{\displaystyle |\psi \rangle } 6363: 6005: 5913: 5892: 5883: 5864: 5845: 5827: 5766: 5758: 5641: 5608: 5577: 5218: 5143: 5038: 5022: 5008: 4992: 4798: 4774: 4736: 4708: 4524: 4519: 4505: 4498: 4405:{\displaystyle |\phi \rangle } 4392: 4336: 4332: 4324: 4289: 4274:{\displaystyle |\psi \rangle } 4261: 4231: 4197: 4192: 4184: 4177: 4130: 4125: 4117: 4110: 4066:{\displaystyle |\psi \rangle } 4053: 4016: 4001: 3993: 3976:{\displaystyle |\psi \rangle } 3963: 3907: 3861:{\displaystyle |\psi \rangle } 3848: 3795: 3698: 3677:{\displaystyle |\psi \rangle } 3664: 3629: 3560: 3541:{\displaystyle |\psi \rangle } 3528: 3478: 3444: 3429:{\displaystyle |\psi \rangle } 3416: 3379: 3093: 3027: 3020: 2766: 2730:{\displaystyle |\psi \rangle } 2717: 2694:{\displaystyle \langle \psi |} 2687: 2666:{\displaystyle |\psi \rangle } 2653: 2626:{\displaystyle \langle \psi |} 2619: 2594:{\displaystyle |\psi \rangle } 2581: 2528:{\displaystyle |\psi \rangle } 2515: 2447:. Note that although the word 2414: 2408: 2345:Multiplying a pure state by a 2259: 2255: 2249: 2220: 2214: 2207: 1790: 1774: 1671:Mixed states of wave functions 1632: 1628: 1622: 1593: 1587: 1580: 1437: 1429: 1407: 1399: 1362: 1353: 1339: 1330: 1309: 1297: 1198:Pure states of wave functions 567:Relativistic quantum mechanics 99: 92: 73: 1: 8441:Quantum statistical mechanics 8218:Quantum differential calculus 8140:Delayed-choice quantum eraser 7923:Symmetry in quantum mechanics 5301:quantum statistical mechanics 3593:(as is often the case), then 2740:Scalar products (also called 2030:and the momentum measurement 1189:. Wave function solutions of 1128:Wave function representations 607:Quantum statistical mechanics 7705:In particular, see Sec. 2.3. 7640:Formalism in quantum physics 6547:, while a particle in state 6080:Mathematical generalizations 6052:) being a statistical (said 4686:Superposition of pure states 4364:Pure states vs. bound states 4095:{\displaystyle \mathbf {r} } 4039:This function is called the 3944:{\displaystyle \mathbf {r} } 3312:Electrons are fermions with 3121:assume values from the set 2898:possible values in the set 2643:Riesz representation theorem 2305:Formalism in quantum physics 1069:Eigenvalues and eigenvectors 8243:Quantum stochastic calculus 8233:Quantum measurement problem 8155:Mach–Zehnder interferometer 7464:. BirkhĂ€user. p. 431. 6283:in the above example, with 6151:Quantum harmonic oscillator 4838:{\displaystyle c_{\alpha }} 2871:(1/2, 3/2, 5/2 ...). For a 1536:. The operator serves as a 1086:as discussed in more depth 1063:Eigenstates and pure states 577:Quantum information science 8556: 7727:Geometry of Quantum States 7358:Supplement April 14 1928, 7333:: 172–198. Translation as 7068:. Wiley. pp. 231–235. 6111:Atomic electron transition 5513:{\displaystyle H\otimes K} 5280: 4865:{\displaystyle c_{\beta }} 4689: 4367: 3278:{\displaystyle S_{\nu }=0} 2993: 2890:always assumes one of the 2803: 2474: 2319: 2308: 1549:(which physicists call an 1131: 1066: 1026: 951:for time independence and 8509: 8303:Quantum complexity theory 8281:Quantum cellular automata 7986:Path integral formulation 7624:. Oxford: Pergamon Press. 7620:D. Ter Haar, ed. (1965). 7243:10.1007/s10702-006-1852-1 6225:Dirac (1958), p. 4: 5416:is expressed then as the 5262:in other wave phenomena. 3114:Here, the spin variables 1961:{\displaystyle \Phi _{n}} 1907:{\displaystyle \Phi _{n}} 1702:{\displaystyle 2\times 2} 1414:{\displaystyle |\alpha |} 999:Role in quantum mechanics 8370:Quantum machine learning 8350:Quantum key distribution 8340:Quantum image processing 8330:Quantum error correction 8180:Wheeler's delayed choice 7570:The Scientist Speculates 7039:Messiah, Albert (1966). 4412:is called a bound state 3955:particle), then any ket 3548:has been expressed as a 3241:{\displaystyle S_{\nu }} 2814:has the same dimension ( 2395:projective Hilbert space 2073:incompatible observables 1869:probability distribution 1841:projective Hilbert space 1444:{\displaystyle |\beta |} 1284:Stern–Gerlach experiment 1239:principal quantum number 989:probability distribution 983:, quantized, limited by 612:Quantum machine learning 365:Wheeler's delayed-choice 8286:Quantum finite automata 7650:Isham, Chris J (1995). 6584:Landau (1965), p. 17: " 2980:complex-valued function 2856:reduced Planck constant 2135:are statistical. Thus: 1857:Schrödinger–HJW theorem 1665:time evolution operator 1468:{\displaystyle \alpha } 1257:magnetic quantum number 322:Leggett–Garg inequality 8390:Quantum neural network 7660:Imperial College Press 7586:Zeitschrift fĂŒr Physik 7568:. In I.J. Good (ed.). 6990: 6912: 6861: 6788: 6712: 6684: 6569: 6541: 6495: 6465: 6435: 6407: 6377: 6166:Wave function collapse 6046: 6032:, and the other (over 6026: 5991: 5961: 5934: 5899: 5665: 5616: 5534: 5514: 5484: 5441: 5410: 5383: 5362:state on it, the part 5352: 5256:coherent superposition 5248:double-slit experiment 5237: 5094: 4978: 4866: 4839: 4812: 4750: 4722: 4676: 4656: 4636: 4616: 4596: 4568: 4474: 4436: 4406: 4355: 4275: 4247: 4217: 4144: 4096: 4067: 4033: 3977: 3945: 3923: 3862: 3818: 3779: 3721: 3678: 3643: 3583: 3542: 3501: 3430: 3402: 3292:is very different for 3279: 3242: 3215: 3106: 2960: 2854:that, in units of the 2787: 2731: 2695: 2667: 2627: 2595: 2549: 2529: 2441: 2421: 2383: 2363: 2280: 2000: 1971:The expectation value 1962: 1935: 1908: 1812: 1703: 1656: 1489: 1488:{\displaystyle \beta } 1469: 1445: 1415: 1385: 1316: 1210: 1175: 1048: 993:double-slit experiment 113: 8415:Quantum teleportation 7943:Wave–particle duality 7279:on September 23, 2019 6991: 6913: 6862: 6789: 6713: 6685: 6570: 6542: 6496: 6466: 6436: 6408: 6378: 6094:State on a C*-algebra 6047: 6027: 5992: 5962: 5960:{\displaystyle a_{i}} 5935: 5900: 5666: 5617: 5535: 5515: 5485: 5442: 5440:{\displaystyle H_{2}} 5411: 5409:{\displaystyle H_{1}} 5384: 5382:{\displaystyle H_{2}} 5353: 5238: 5095: 4979: 4867: 4840: 4813: 4751: 4723: 4692:Quantum superposition 4677: 4657: 4637: 4617: 4597: 4569: 4475: 4437: 4407: 4356: 4276: 4248: 4218: 4145: 4097: 4068: 4034: 3978: 3946: 3924: 3863: 3819: 3780: 3722: 3684:are characterized by 3679: 3644: 3584: 3550:quantum superposition 3543: 3502: 3431: 3403: 3280: 3243: 3216: 3107: 2994:Further information: 2961: 2841:group representations 2788: 2732: 2696: 2668: 2628: 2596: 2570:, dual to each other. 2550: 2548:{\displaystyle \psi } 2530: 2491:Hermitian conjugation 2442: 2422: 2384: 2364: 2281: 2001: 1963: 1936: 1934:{\displaystyle P_{n}} 1909: 1877:uncertainty principle 1813: 1704: 1657: 1490: 1470: 1446: 1416: 1386: 1317: 1207:Probability densities 1205: 1176: 1174:{\displaystyle x,y,z} 1067:Further information: 1057:uncertainty principle 1049: 987:, and only provide a 985:uncertainty relations 953:quantum vacuum states 929:vector quantum states 307:Elitzur–Vaidman 297:Davisson–Germer 114: 8446:Quantum field theory 8375:Quantum metamaterial 8320:Quantum cryptography 8050:Consistent histories 7574:Footnote 13 on p.180 7299:"The Density Matrix" 7174:Holevo, Alexander S. 6936: 6875: 6871:), which means that 6869:Dirac delta function 6798: 6722: 6694: 6664: 6551: 6505: 6475: 6445: 6417: 6387: 6359: 6036: 6001: 5981: 5944: 5909: 5709: 5637: 5547: 5524: 5498: 5474: 5424: 5393: 5366: 5322: 5308:statistical ensemble 5299:of pure states (see 5297:statistical ensemble 5271:Schrödinger equation 5252:quantum interference 5104: 4988: 4879: 4849: 4822: 4760: 4732: 4704: 4666: 4646: 4626: 4606: 4578: 4484: 4449: 4420: 4388: 4285: 4257: 4227: 4154: 4106: 4084: 4049: 3987: 3959: 3933: 3903: 3844: 3791: 3731: 3688: 3660: 3597: 3556: 3524: 3440: 3412: 3375: 3256: 3225: 3125: 3016: 2902: 2749: 2713: 2677: 2673:as a column vector, 2649: 2609: 2577: 2539: 2511: 2431: 2400: 2373: 2353: 2295:quantum field theory 2203: 1975: 1945: 1918: 1891: 1884:statistical ensemble 1733: 1727:quantum entanglement 1725:, which exemplifies 1687: 1576: 1479: 1459: 1425: 1395: 1326: 1294: 1153: 1111:parametric equations 1095:Schrödinger equation 1038: 957:quantum field theory 572:Quantum field theory 484:Consistent histories 121:Schrödinger equation 48: 8431:Quantum fluctuation 8400:Quantum programming 8360:Quantum logic gates 8345:Quantum information 8325:Quantum electronics 7800:Classical mechanics 7598:1927ZPhy...45..430L 7517:. Cambridge, Mass: 7305:on January 15, 2012 7235:2006FoPhL..19...95K 7144:Rieffel, Eleanor G. 5690:von Neumann entropy 5462:), usually denoted 5293:mixed quantum state 5178: 5083: 5065: 4376:pure point spectrum 3290:identical particles 3006:spatial coordinates 2996:Particle statistics 2883:spin quantum number 2875:particle with spin 2867:(0, 1, 2 ...) or a 2485:, scalar products, 2197:Schrödinger picture 1555:quantum uncertainty 1187:mixed quantum state 1009:equations of motion 969:classical mechanics 360:Stern–Gerlach 157:Classical mechanics 8484:in popular culture 8266:Quantum algorithms 8114:Von Neumann–Wigner 8094:Objective collapse 7805:Old quantum theory 7606:10.1007/bf01343064 6986: 6908: 6857: 6784: 6708: 6680: 6565: 6537: 6491: 6461: 6431: 6403: 6373: 6355:Note that a state 6342:Gottfried (2013), 6156:Quantum logic gate 6136:No-cloning theorem 6100:for more details. 6042: 6022: 5987: 5957: 5930: 5895: 5805: 5795: 5733: 5661: 5612: 5565: 5530: 5510: 5480: 5437: 5406: 5379: 5348: 5289:pure quantum state 5258:, by analogy with 5233: 5164: 5090: 5069: 5051: 4974: 4862: 4835: 4808: 4746: 4718: 4672: 4652: 4632: 4612: 4592: 4564: 4470: 4432: 4402: 4351: 4271: 4243: 4213: 4140: 4092: 4063: 4029: 3973: 3941: 3919: 3858: 3814: 3775: 3743: 3717: 3674: 3639: 3579: 3538: 3497: 3466: 3426: 3398: 3369:linear combination 3275: 3238: 3211: 3102: 2956: 2783: 2727: 2691: 2663: 2623: 2591: 2545: 2525: 2437: 2417: 2379: 2359: 2276: 2238: 2171:Heisenberg picture 2041:(at the same time 1996: 1958: 1931: 1904: 1861:convex combination 1808: 1791:↓ ↑ 1775:↑ ↓ 1699: 1652: 1611: 1570:linear combination 1485: 1465: 1441: 1411: 1381: 1312: 1211: 1183:pure quantum state 1171: 1147:degrees of freedom 1044: 927:the more abstract 548:Von Neumann–Wigner 528:Objective-collapse 327:Mach–Zehnder 317:Leggett inequality 312:Franck–Hertz 162:Old quantum theory 109: 8527: 8526: 8501:Quantum mysticism 8479:Schrödinger's cat 8410:Quantum simulator 8380:Quantum metrology 8308:Quantum computing 8271:Quantum amplifier 8248:Quantum spacetime 8213:Quantum cosmology 8203:Quantum chemistry 7918:Scattering theory 7866:Zero-point energy 7861:Degenerate levels 7769:Quantum mechanics 7700:978-3-540-17093-8 7687:Robinson, Derek W 7669:978-1-86094-001-9 7528:978-0-262-04613-8 7496:978-0-465-06290-4 7471:978-3-319-14044-5 7159:978-0-262-01506-6 7066:Quantum Mechanics 7041:Quantum Mechanics 6141:Orthonormal basis 6045:{\displaystyle s} 5990:{\displaystyle i} 5796: 5786: 5724: 5697:expectation value 5556: 5533:{\displaystyle K} 5483:{\displaystyle H} 5267:Rabi oscillations 5179: 4930: 4927: 4675:{\displaystyle K} 4655:{\displaystyle 1} 4635:{\displaystyle t} 4615:{\displaystyle K} 4045:corresponding to 3929:with eigenvalues 3734: 3457: 3330:(although in the 3288:The treatment of 2707:complex conjugate 2465:geometrical sense 2440:{\displaystyle H} 2382:{\displaystyle H} 2362:{\displaystyle H} 2291:quantum mechanics 2229: 2006:of an observable 1887:different states 1760: 1759: 1602: 1508:, correspond to 1047:{\displaystyle x} 949:stationary states 907:Quantum mechanics 895: 894: 602:Scattering theory 582:Quantum computing 355:Schrödinger's cat 287:Bell's inequality 95: 70: 39:Quantum mechanics 16:(Redirected from 8547: 8517: 8516: 8228:Quantum geometry 8223:Quantum dynamics 8080:Superdeterminism 7976:Matrix mechanics 7831:Bra–ket notation 7762: 7755: 7748: 7739: 7730: 7704: 7673: 7657: 7627: 7625: 7617: 7592:(5–6): 430–441. 7581: 7575: 7573: 7567: 7555: 7549: 7539: 7533: 7532: 7511:Zwiebach, Barton 7507: 7501: 7500: 7482: 7476: 7475: 7457: 7451: 7450: 7448: 7430: 7421: 7420: 7395: 7386: 7376: 7365: 7348: 7342: 7321: 7315: 7314: 7312: 7310: 7301:. Archived from 7295: 7289: 7288: 7286: 7284: 7275:. Archived from 7269: 7263: 7262: 7228: 7226:quant-ph/0305068 7206: 7200: 7199: 7170: 7164: 7163: 7140: 7134: 7133: 7115: 7109: 7108: 7085: 7070: 7069: 7061: 7055: 7054: 7036: 6996: 6995: 6993: 6992: 6987: 6985: 6984: 6957: 6956: 6931: 6924: 6918: 6917: 6915: 6914: 6909: 6895: 6890: 6885: 6866: 6864: 6863: 6858: 6853: 6845: 6841: 6823: 6819: 6813: 6808: 6793: 6791: 6790: 6785: 6771: 6767: 6761: 6756: 6747: 6743: 6737: 6736: 6717: 6715: 6714: 6709: 6701: 6689: 6687: 6686: 6681: 6676: 6671: 6658: 6652: 6650: 6630: 6629: 6616: 6582: 6576: 6574: 6572: 6571: 6566: 6558: 6546: 6544: 6543: 6538: 6512: 6500: 6498: 6497: 6492: 6487: 6482: 6470: 6468: 6467: 6462: 6457: 6452: 6440: 6438: 6437: 6432: 6424: 6412: 6410: 6409: 6404: 6399: 6394: 6382: 6380: 6379: 6374: 6366: 6353: 6347: 6340: 6334: 6332: 6331: 6317: 6311: 6307: 6301: 6299: 6282: 6264: 6245: 6239: 6235: 6229: 6223: 6217: 6211: 6200: 6188: 6161:Stationary state 6064: 6051: 6049: 6048: 6043: 6031: 6029: 6028: 6023: 6018: 6017: 6008: 5996: 5994: 5993: 5988: 5976: 5972: 5966: 5964: 5963: 5958: 5956: 5955: 5939: 5937: 5936: 5931: 5926: 5925: 5916: 5904: 5902: 5901: 5896: 5873: 5872: 5867: 5858: 5857: 5848: 5843: 5842: 5830: 5825: 5824: 5815: 5814: 5804: 5794: 5779: 5778: 5769: 5761: 5756: 5755: 5743: 5742: 5732: 5704: 5687: 5670: 5668: 5667: 5662: 5654: 5653: 5644: 5632: 5621: 5619: 5618: 5613: 5611: 5606: 5605: 5590: 5589: 5580: 5575: 5574: 5564: 5539: 5537: 5536: 5531: 5519: 5517: 5516: 5511: 5489: 5487: 5486: 5481: 5460:density operator 5446: 5444: 5443: 5438: 5436: 5435: 5415: 5413: 5412: 5407: 5405: 5404: 5388: 5386: 5385: 5380: 5378: 5377: 5357: 5355: 5354: 5349: 5347: 5346: 5334: 5333: 5242: 5240: 5239: 5234: 5232: 5228: 5221: 5216: 5215: 5214: 5213: 5198: 5197: 5180: 5177: 5172: 5157: 5146: 5141: 5140: 5126: 5125: 5124: 5123: 5099: 5097: 5096: 5091: 5082: 5077: 5064: 5059: 5047: 5046: 5041: 5035: 5034: 5025: 5017: 5016: 5011: 5005: 5004: 4995: 4983: 4981: 4980: 4975: 4973: 4972: 4971: 4970: 4953: 4952: 4940: 4939: 4928: 4925: 4924: 4923: 4922: 4921: 4904: 4903: 4891: 4890: 4871: 4869: 4868: 4863: 4861: 4860: 4844: 4842: 4841: 4836: 4834: 4833: 4817: 4815: 4814: 4809: 4801: 4796: 4795: 4777: 4772: 4771: 4755: 4753: 4752: 4747: 4739: 4727: 4725: 4724: 4719: 4711: 4681: 4679: 4678: 4673: 4661: 4659: 4658: 4653: 4641: 4639: 4638: 4633: 4621: 4619: 4618: 4613: 4601: 4599: 4598: 4593: 4591: 4573: 4571: 4570: 4565: 4551: 4546: 4545: 4540: 4533: 4532: 4527: 4512: 4501: 4496: 4495: 4479: 4477: 4476: 4471: 4469: 4468: 4463: 4441: 4439: 4438: 4433: 4411: 4409: 4408: 4403: 4395: 4360: 4358: 4357: 4352: 4344: 4339: 4331: 4319: 4314: 4313: 4292: 4280: 4278: 4277: 4272: 4264: 4252: 4250: 4249: 4244: 4239: 4234: 4222: 4220: 4219: 4214: 4206: 4205: 4200: 4191: 4180: 4174: 4169: 4168: 4149: 4147: 4146: 4141: 4139: 4138: 4133: 4124: 4113: 4101: 4099: 4098: 4093: 4091: 4072: 4070: 4069: 4064: 4056: 4038: 4036: 4035: 4030: 4019: 4014: 4000: 3982: 3980: 3979: 3974: 3966: 3950: 3948: 3947: 3942: 3940: 3928: 3926: 3925: 3920: 3915: 3910: 3889: 3887: 3876: 3867: 3865: 3864: 3859: 3851: 3839: 3823: 3821: 3820: 3815: 3810: 3809: 3808: 3798: 3784: 3782: 3781: 3776: 3768: 3767: 3762: 3758: 3757: 3742: 3726: 3724: 3723: 3718: 3701: 3683: 3681: 3680: 3675: 3667: 3648: 3646: 3645: 3640: 3632: 3627: 3626: 3625: 3609: 3608: 3588: 3586: 3585: 3580: 3575: 3574: 3573: 3563: 3547: 3545: 3544: 3539: 3531: 3515: 3506: 3504: 3503: 3498: 3493: 3492: 3491: 3481: 3476: 3475: 3465: 3447: 3435: 3433: 3432: 3427: 3419: 3407: 3405: 3404: 3399: 3394: 3393: 3392: 3382: 3346: 3329: 3318: 3284: 3282: 3281: 3276: 3268: 3267: 3247: 3245: 3244: 3239: 3237: 3236: 3220: 3218: 3217: 3212: 3207: 3206: 3187: 3186: 3160: 3159: 3143: 3142: 3111: 3109: 3108: 3103: 3092: 3091: 3078: 3077: 3072: 3055: 3054: 3041: 3040: 3035: 3023: 2965: 2963: 2962: 2957: 2897: 2889: 2880: 2862: 2853: 2812:angular momentum 2794: 2792: 2790: 2789: 2784: 2779: 2778: 2769: 2764: 2763: 2736: 2734: 2733: 2728: 2720: 2700: 2698: 2697: 2692: 2690: 2672: 2670: 2669: 2664: 2656: 2632: 2630: 2629: 2624: 2622: 2600: 2598: 2597: 2592: 2584: 2554: 2552: 2551: 2546: 2534: 2532: 2531: 2526: 2518: 2500:bra–ket notation 2483:linear operators 2477:Bra–ket notation 2471:Bra–ket notation 2446: 2444: 2443: 2438: 2426: 2424: 2423: 2418: 2407: 2388: 2386: 2385: 2380: 2368: 2366: 2365: 2360: 2285: 2283: 2282: 2277: 2272: 2271: 2262: 2248: 2247: 2237: 2210: 2194: 2183: 2168: 2145:entangled states 2134: 2128: 2122: 2116: 2110: 2104: 2098: 2092: 2086: 2080: 2044: 2040: 2029: 2011: 2005: 2003: 2002: 1997: 1995: 1994: 1989: 1967: 1965: 1964: 1959: 1957: 1956: 1940: 1938: 1937: 1932: 1930: 1929: 1913: 1911: 1910: 1905: 1903: 1902: 1873:linear operators 1849:density matrices 1831: 1830: 1826: 1817: 1815: 1814: 1809: 1804: 1803: 1797: 1793: 1781: 1777: 1768: 1767: 1761: 1755: 1751: 1746: 1719:bra–ket notation 1708: 1706: 1705: 1700: 1661: 1659: 1658: 1653: 1645: 1644: 1635: 1621: 1620: 1610: 1583: 1566:bra–ket notation 1507: 1494: 1492: 1491: 1486: 1474: 1472: 1471: 1466: 1450: 1448: 1447: 1442: 1440: 1432: 1420: 1418: 1417: 1412: 1410: 1402: 1390: 1388: 1387: 1382: 1371: 1370: 1365: 1356: 1348: 1347: 1342: 1333: 1321: 1319: 1318: 1313: 1281: 1263: 1254: 1245: 1180: 1178: 1177: 1172: 1053: 1051: 1050: 1045: 887: 880: 873: 514:Superdeterminism 167:Bra–ket notation 118: 116: 115: 110: 102: 97: 96: 88: 76: 71: 69: 58: 30: 21: 8555: 8554: 8550: 8549: 8548: 8546: 8545: 8544: 8530: 8529: 8528: 8523: 8505: 8491:Wigner's friend 8467: 8458:Quantum gravity 8419: 8405:Quantum sensing 8385:Quantum network 8365:Quantum machine 8335:Quantum imaging 8298:Quantum circuit 8293:Quantum channel 8252: 8198:Quantum biology 8184: 8160:Elitzur–Vaidman 8135:Davisson–Germer 8118: 8070:Hidden-variable 8060:de Broglie–Bohm 8037:Interpretations 8031: 7995: 7949: 7836:Complementarity 7814: 7771: 7766: 7720: 7701: 7681: 7670: 7649: 7636: 7634:Further reading 7631: 7630: 7619: 7583: 7582: 7578: 7565: 7557: 7556: 7552: 7540: 7536: 7529: 7509: 7508: 7504: 7497: 7484: 7483: 7479: 7472: 7459: 7458: 7454: 7446: 7438:Evgeny Lifshitz 7432: 7431: 7424: 7417: 7399:Gottfried, Kurt 7397: 7396: 7389: 7377: 7368: 7349: 7345: 7322: 7318: 7308: 7306: 7297: 7296: 7292: 7282: 7280: 7271: 7270: 7266: 7208: 7207: 7203: 7188: 7172: 7171: 7167: 7160: 7142: 7141: 7137: 7130: 7117: 7116: 7112: 7105: 7087: 7086: 7073: 7063: 7062: 7058: 7051: 7038: 7037: 7010: 7005: 7000: 6999: 6976: 6948: 6934: 6933: 6927: 6925: 6921: 6873: 6872: 6836: 6814: 6796: 6795: 6762: 6738: 6728: 6720: 6719: 6692: 6691: 6662: 6661: 6659: 6655: 6644: 6640: 6632: 6628:′⟩ 6627: 6623: 6619: 6618: 6614: 6610: 6598: 6597: 6592: 6590: 6585: 6583: 6579: 6549: 6548: 6503: 6502: 6473: 6472: 6443: 6442: 6415: 6414: 6385: 6384: 6357: 6356: 6354: 6350: 6341: 6337: 6321: 6320: 6318: 6314: 6308: 6304: 6297: 6290: 6284: 6280: 6266: 6262: 6248: 6246: 6242: 6236: 6232: 6224: 6220: 6202: 6191: 6189: 6185: 6180: 6175: 6106: 6082: 6062: 6057: 6034: 6033: 6009: 5999: 5998: 5979: 5978: 5974: 5968: 5947: 5942: 5941: 5917: 5907: 5906: 5862: 5849: 5834: 5816: 5806: 5770: 5747: 5734: 5707: 5706: 5700: 5683: 5645: 5635: 5634: 5631: 5623: 5597: 5581: 5566: 5545: 5544: 5522: 5521: 5496: 5495: 5472: 5471: 5427: 5422: 5421: 5396: 5391: 5390: 5369: 5364: 5363: 5338: 5325: 5320: 5319: 5285: 5279: 5205: 5189: 5181: 5132: 5131: 5127: 5115: 5107: 5102: 5101: 5036: 5026: 5006: 4996: 4986: 4985: 4962: 4954: 4944: 4931: 4913: 4905: 4895: 4882: 4877: 4876: 4852: 4847: 4846: 4825: 4820: 4819: 4787: 4763: 4758: 4757: 4730: 4729: 4702: 4701: 4694: 4688: 4664: 4663: 4644: 4643: 4624: 4623: 4604: 4603: 4576: 4575: 4535: 4522: 4487: 4482: 4481: 4458: 4447: 4446: 4418: 4417: 4386: 4385: 4372: 4366: 4305: 4283: 4282: 4255: 4254: 4225: 4224: 4195: 4160: 4152: 4151: 4128: 4104: 4103: 4082: 4081: 4047: 4046: 3985: 3984: 3957: 3956: 3931: 3930: 3901: 3900: 3885: 3880: 3878: 3874: 3869: 3842: 3841: 3837: 3832: 3800: 3789: 3788: 3749: 3745: 3744: 3729: 3728: 3686: 3685: 3658: 3657: 3617: 3600: 3595: 3594: 3565: 3554: 3553: 3522: 3521: 3518:complex numbers 3513: 3508: 3483: 3467: 3438: 3437: 3436:can be written 3410: 3409: 3384: 3373: 3372: 3357: 3349:tensor products 3342: 3324: 3313: 3259: 3254: 3253: 3248:is the spin of 3228: 3223: 3222: 3198: 3178: 3151: 3134: 3123: 3122: 3119: 3083: 3067: 3046: 3030: 3014: 3013: 2998: 2992: 2900: 2899: 2891: 2885: 2876: 2863:, is either an 2858: 2849: 2828:Planck constant 2808: 2802: 2770: 2755: 2747: 2746: 2745: 2711: 2710: 2705:and entry-wise 2675: 2674: 2647: 2646: 2607: 2606: 2575: 2574: 2537: 2536: 2509: 2508: 2479: 2473: 2429: 2428: 2398: 2397: 2371: 2370: 2351: 2350: 2324: 2318: 2313: 2307: 2297:. Compare with 2263: 2239: 2201: 2200: 2185: 2174: 2164: 2161: 2130: 2124: 2118: 2112: 2106: 2100: 2094: 2088: 2082: 2076: 2042: 2031: 2020: 2007: 1978: 1973: 1972: 1948: 1943: 1942: 1921: 1916: 1915: 1894: 1889: 1888: 1845:complex numbers 1828: 1824: 1823: 1818:which involves 1789: 1785: 1773: 1769: 1736: 1731: 1730: 1709:matrix that is 1685: 1684: 1673: 1636: 1612: 1574: 1573: 1538:linear function 1503: 1477: 1476: 1457: 1456: 1453:absolute values 1423: 1422: 1393: 1392: 1360: 1337: 1324: 1323: 1292: 1291: 1280: 1272: 1259: 1250: 1241: 1227:energy spectrum 1223:quantum numbers 1200: 1151: 1150: 1136: 1130: 1107:representations 1103: 1101:Representations 1071: 1065: 1036: 1035: 1031: 1025: 1001: 981:complex numbers 965: 945:coherent states 899:quantum physics 891: 862: 861: 860: 625: 617: 616: 562: 561:Advanced topics 554: 553: 552: 504:Hidden-variable 494:de Broglie–Bohm 473: 471:Interpretations 463: 462: 461: 431: 423: 422: 421: 379: 371: 370: 369: 336: 292:CHSH inequality 281: 273: 272: 271: 200:Complementarity 194: 186: 185: 184: 152: 123: 62: 46: 45: 28: 23: 22: 15: 12: 11: 5: 8553: 8551: 8543: 8542: 8540:Quantum states 8532: 8531: 8525: 8524: 8522: 8521: 8510: 8507: 8506: 8504: 8503: 8498: 8493: 8488: 8487: 8486: 8475: 8473: 8469: 8468: 8466: 8465: 8460: 8455: 8454: 8453: 8443: 8438: 8436:Casimir effect 8433: 8427: 8425: 8421: 8420: 8418: 8417: 8412: 8407: 8402: 8397: 8395:Quantum optics 8392: 8387: 8382: 8377: 8372: 8367: 8362: 8357: 8352: 8347: 8342: 8337: 8332: 8327: 8322: 8317: 8316: 8315: 8305: 8300: 8295: 8290: 8289: 8288: 8278: 8273: 8268: 8262: 8260: 8254: 8253: 8251: 8250: 8245: 8240: 8235: 8230: 8225: 8220: 8215: 8210: 8205: 8200: 8194: 8192: 8186: 8185: 8183: 8182: 8177: 8172: 8170:Quantum eraser 8167: 8162: 8157: 8152: 8147: 8142: 8137: 8132: 8126: 8124: 8120: 8119: 8117: 8116: 8111: 8106: 8101: 8096: 8091: 8086: 8085: 8084: 8083: 8082: 8067: 8062: 8057: 8052: 8047: 8041: 8039: 8033: 8032: 8030: 8029: 8024: 8019: 8014: 8009: 8003: 8001: 7997: 7996: 7994: 7993: 7988: 7983: 7978: 7973: 7968: 7963: 7957: 7955: 7951: 7950: 7948: 7947: 7946: 7945: 7940: 7930: 7925: 7920: 7915: 7910: 7905: 7900: 7895: 7890: 7885: 7880: 7875: 7870: 7869: 7868: 7863: 7858: 7853: 7843: 7841:Density matrix 7838: 7833: 7828: 7822: 7820: 7816: 7815: 7813: 7812: 7807: 7802: 7797: 7796: 7795: 7785: 7779: 7777: 7773: 7772: 7767: 7765: 7764: 7757: 7750: 7742: 7736: 7735: 7707: 7706: 7703:. 2nd edition. 7699: 7675: 7674: 7668: 7635: 7632: 7629: 7628: 7576: 7550: 7534: 7527: 7502: 7495: 7477: 7470: 7452: 7422: 7415: 7387: 7366: 7343: 7324:Heisenberg, W. 7316: 7290: 7264: 7201: 7186: 7165: 7158: 7135: 7128: 7110: 7103: 7071: 7056: 7049: 7007: 7006: 7004: 7001: 6998: 6997: 6983: 6979: 6975: 6972: 6969: 6966: 6963: 6960: 6955: 6951: 6947: 6944: 6941: 6919: 6907: 6904: 6901: 6898: 6894: 6889: 6884: 6880: 6856: 6852: 6848: 6844: 6840: 6835: 6832: 6829: 6826: 6822: 6818: 6812: 6807: 6803: 6783: 6780: 6777: 6774: 6770: 6766: 6760: 6755: 6751: 6746: 6742: 6735: 6731: 6727: 6707: 6704: 6700: 6679: 6675: 6670: 6653: 6642: 6638: 6625: 6621: 6612: 6608: 6595: 6594: 6588: 6587: 6577: 6564: 6561: 6557: 6536: 6533: 6530: 6527: 6524: 6521: 6518: 6515: 6511: 6490: 6486: 6481: 6460: 6456: 6451: 6430: 6427: 6423: 6402: 6398: 6393: 6372: 6369: 6365: 6348: 6335: 6312: 6302: 6295: 6288: 6278: 6260: 6240: 6230: 6218: 6182: 6181: 6179: 6176: 6174: 6173: 6168: 6163: 6158: 6153: 6148: 6143: 6138: 6133: 6128: 6123: 6118: 6113: 6107: 6105: 6102: 6081: 6078: 6060: 6041: 6021: 6016: 6012: 6007: 5986: 5954: 5950: 5929: 5924: 5920: 5915: 5894: 5891: 5888: 5885: 5882: 5879: 5876: 5871: 5866: 5861: 5856: 5852: 5847: 5841: 5837: 5833: 5829: 5823: 5819: 5813: 5809: 5803: 5799: 5793: 5789: 5785: 5782: 5777: 5773: 5768: 5764: 5760: 5754: 5750: 5746: 5741: 5737: 5731: 5727: 5723: 5720: 5717: 5714: 5660: 5657: 5652: 5648: 5643: 5627: 5610: 5604: 5600: 5596: 5593: 5588: 5584: 5579: 5573: 5569: 5563: 5559: 5555: 5552: 5529: 5509: 5506: 5503: 5479: 5456:density matrix 5450:A mixed state 5434: 5430: 5403: 5399: 5376: 5372: 5345: 5341: 5337: 5332: 5328: 5283:Density matrix 5281:Main article: 5278: 5275: 5231: 5227: 5224: 5220: 5212: 5208: 5204: 5201: 5196: 5192: 5188: 5184: 5176: 5171: 5167: 5163: 5160: 5155: 5152: 5149: 5145: 5139: 5135: 5130: 5122: 5118: 5114: 5110: 5089: 5086: 5081: 5076: 5072: 5068: 5063: 5058: 5054: 5050: 5045: 5040: 5033: 5029: 5024: 5020: 5015: 5010: 5003: 4999: 4994: 4969: 4965: 4961: 4957: 4951: 4947: 4943: 4938: 4934: 4920: 4916: 4912: 4908: 4902: 4898: 4894: 4889: 4885: 4859: 4855: 4832: 4828: 4807: 4804: 4800: 4794: 4790: 4786: 4783: 4780: 4776: 4770: 4766: 4745: 4742: 4738: 4717: 4714: 4710: 4690:Main article: 4687: 4684: 4671: 4651: 4631: 4611: 4590: 4586: 4583: 4563: 4560: 4557: 4554: 4550: 4544: 4539: 4531: 4526: 4521: 4518: 4515: 4511: 4507: 4504: 4500: 4494: 4490: 4467: 4462: 4457: 4454: 4431: 4428: 4425: 4414:if and only if 4401: 4398: 4394: 4365: 4362: 4350: 4347: 4343: 4338: 4334: 4330: 4326: 4323: 4318: 4312: 4308: 4304: 4301: 4298: 4295: 4291: 4270: 4267: 4263: 4242: 4238: 4233: 4212: 4209: 4204: 4199: 4194: 4190: 4186: 4183: 4179: 4173: 4167: 4163: 4159: 4137: 4132: 4127: 4123: 4119: 4116: 4112: 4090: 4062: 4059: 4055: 4028: 4025: 4022: 4018: 4013: 4009: 4006: 4003: 3999: 3995: 3992: 3972: 3969: 3965: 3939: 3918: 3914: 3909: 3896:position basis 3883: 3872: 3857: 3854: 3850: 3835: 3813: 3807: 3803: 3797: 3774: 3771: 3766: 3761: 3756: 3752: 3748: 3741: 3737: 3716: 3713: 3710: 3707: 3704: 3700: 3696: 3693: 3673: 3670: 3666: 3638: 3635: 3631: 3624: 3620: 3615: 3612: 3607: 3603: 3578: 3572: 3568: 3562: 3552:of the states 3537: 3534: 3530: 3511: 3496: 3490: 3486: 3480: 3474: 3470: 3464: 3460: 3456: 3453: 3450: 3446: 3425: 3422: 3418: 3397: 3391: 3387: 3381: 3356: 3353: 3274: 3271: 3266: 3262: 3252:-th particle. 3235: 3231: 3210: 3205: 3201: 3196: 3193: 3190: 3185: 3181: 3176: 3173: 3169: 3166: 3163: 3158: 3154: 3150: 3146: 3141: 3137: 3133: 3130: 3117: 3101: 3098: 3095: 3090: 3086: 3081: 3076: 3071: 3065: 3062: 3058: 3053: 3049: 3044: 3039: 3034: 3029: 3026: 3022: 2991: 2988: 2984:quantum number 2955: 2952: 2949: 2946: 2943: 2940: 2937: 2934: 2931: 2928: 2925: 2922: 2919: 2916: 2913: 2910: 2907: 2804:Main article: 2801: 2798: 2797: 2796: 2782: 2777: 2773: 2768: 2762: 2758: 2754: 2738: 2726: 2723: 2719: 2689: 2685: 2682: 2662: 2659: 2655: 2621: 2617: 2614: 2590: 2587: 2583: 2571: 2560: 2544: 2524: 2521: 2517: 2475:Main article: 2472: 2469: 2436: 2416: 2413: 2410: 2406: 2378: 2358: 2328:linear algebra 2317: 2314: 2306: 2303: 2275: 2270: 2266: 2261: 2257: 2254: 2251: 2246: 2242: 2236: 2232: 2228: 2225: 2222: 2219: 2216: 2213: 2209: 2160: 2157: 2153:Bell's theorem 1993: 1988: 1985: 1982: 1955: 1951: 1928: 1924: 1901: 1897: 1807: 1802: 1796: 1792: 1788: 1784: 1780: 1776: 1772: 1766: 1758: 1754: 1749: 1745: 1742: 1739: 1698: 1695: 1692: 1672: 1669: 1651: 1648: 1643: 1639: 1634: 1630: 1627: 1624: 1619: 1615: 1609: 1605: 1601: 1598: 1595: 1592: 1589: 1586: 1582: 1484: 1464: 1439: 1435: 1431: 1409: 1405: 1401: 1380: 1377: 1374: 1369: 1364: 1359: 1355: 1351: 1346: 1341: 1336: 1332: 1311: 1308: 1305: 1302: 1299: 1276: 1199: 1196: 1170: 1167: 1164: 1161: 1158: 1139:Wave functions 1132:Main article: 1129: 1126: 1102: 1099: 1064: 1061: 1043: 1027:Main article: 1024: 1021: 1000: 997: 964: 961: 933: 932: 925: 922:wave functions 893: 892: 890: 889: 882: 875: 867: 864: 863: 859: 858: 853: 848: 843: 838: 833: 828: 823: 818: 813: 808: 803: 798: 793: 788: 783: 778: 773: 768: 763: 758: 753: 748: 743: 738: 733: 728: 723: 718: 713: 708: 703: 698: 693: 688: 683: 678: 673: 668: 663: 658: 653: 648: 643: 638: 633: 627: 626: 623: 622: 619: 618: 615: 614: 609: 604: 599: 597:Density matrix 594: 589: 584: 579: 574: 569: 563: 560: 559: 556: 555: 551: 550: 545: 540: 535: 530: 525: 520: 519: 518: 517: 516: 501: 496: 491: 486: 481: 475: 474: 469: 468: 465: 464: 460: 459: 454: 449: 444: 439: 433: 432: 429: 428: 425: 424: 420: 419: 414: 409: 404: 399: 394: 388: 387: 386: 380: 377: 376: 373: 372: 368: 367: 362: 357: 351: 350: 349: 348: 347: 345:Delayed-choice 340:Quantum eraser 335: 334: 329: 324: 319: 314: 309: 304: 299: 294: 289: 283: 282: 279: 278: 275: 274: 270: 269: 268: 267: 257: 252: 247: 242: 237: 232: 230:Quantum number 227: 222: 217: 212: 207: 202: 196: 195: 192: 191: 188: 187: 183: 182: 177: 171: 170: 169: 164: 159: 153: 150: 149: 146: 145: 144: 143: 138: 133: 125: 124: 119: 108: 105: 101: 94: 91: 85: 82: 79: 75: 68: 65: 61: 56: 53: 42: 41: 35: 34: 26: 24: 14: 13: 10: 9: 6: 4: 3: 2: 8552: 8541: 8538: 8537: 8535: 8520: 8512: 8511: 8508: 8502: 8499: 8497: 8494: 8492: 8489: 8485: 8482: 8481: 8480: 8477: 8476: 8474: 8470: 8464: 8461: 8459: 8456: 8452: 8449: 8448: 8447: 8444: 8442: 8439: 8437: 8434: 8432: 8429: 8428: 8426: 8422: 8416: 8413: 8411: 8408: 8406: 8403: 8401: 8398: 8396: 8393: 8391: 8388: 8386: 8383: 8381: 8378: 8376: 8373: 8371: 8368: 8366: 8363: 8361: 8358: 8356: 8355:Quantum logic 8353: 8351: 8348: 8346: 8343: 8341: 8338: 8336: 8333: 8331: 8328: 8326: 8323: 8321: 8318: 8314: 8311: 8310: 8309: 8306: 8304: 8301: 8299: 8296: 8294: 8291: 8287: 8284: 8283: 8282: 8279: 8277: 8274: 8272: 8269: 8267: 8264: 8263: 8261: 8259: 8255: 8249: 8246: 8244: 8241: 8239: 8236: 8234: 8231: 8229: 8226: 8224: 8221: 8219: 8216: 8214: 8211: 8209: 8208:Quantum chaos 8206: 8204: 8201: 8199: 8196: 8195: 8193: 8191: 8187: 8181: 8178: 8176: 8175:Stern–Gerlach 8173: 8171: 8168: 8166: 8163: 8161: 8158: 8156: 8153: 8151: 8148: 8146: 8143: 8141: 8138: 8136: 8133: 8131: 8128: 8127: 8125: 8121: 8115: 8112: 8110: 8109:Transactional 8107: 8105: 8102: 8100: 8099:Quantum logic 8097: 8095: 8092: 8090: 8087: 8081: 8078: 8077: 8076: 8073: 8072: 8071: 8068: 8066: 8063: 8061: 8058: 8056: 8053: 8051: 8048: 8046: 8043: 8042: 8040: 8038: 8034: 8028: 8025: 8023: 8020: 8018: 8015: 8013: 8010: 8008: 8005: 8004: 8002: 7998: 7992: 7989: 7987: 7984: 7982: 7979: 7977: 7974: 7972: 7969: 7967: 7964: 7962: 7959: 7958: 7956: 7952: 7944: 7941: 7939: 7936: 7935: 7934: 7933:Wave function 7931: 7929: 7926: 7924: 7921: 7919: 7916: 7914: 7911: 7909: 7908:Superposition 7906: 7904: 7903:Quantum state 7901: 7899: 7896: 7894: 7891: 7889: 7886: 7884: 7881: 7879: 7876: 7874: 7871: 7867: 7864: 7862: 7859: 7857: 7856:Excited state 7854: 7852: 7849: 7848: 7847: 7844: 7842: 7839: 7837: 7834: 7832: 7829: 7827: 7824: 7823: 7821: 7817: 7811: 7808: 7806: 7803: 7801: 7798: 7794: 7791: 7790: 7789: 7786: 7784: 7781: 7780: 7778: 7774: 7770: 7763: 7758: 7756: 7751: 7749: 7744: 7743: 7740: 7734: 7728: 7724: 7721:Bengtsson I; 7719: 7718: 7717: 7714: 7712: 7702: 7696: 7692: 7688: 7684: 7683:Bratteli, Ola 7680: 7679: 7678: 7671: 7665: 7661: 7656: 7655: 7648: 7647: 7646: 7643: 7641: 7633: 7623: 7615: 7611: 7607: 7603: 7599: 7595: 7591: 7587: 7580: 7577: 7571: 7564: 7560: 7559:Eugene Wigner 7554: 7551: 7547: 7545: 7538: 7535: 7530: 7524: 7520: 7516: 7512: 7506: 7503: 7498: 7492: 7488: 7481: 7478: 7473: 7467: 7463: 7456: 7453: 7445: 7444: 7439: 7435: 7429: 7427: 7423: 7418: 7416:9780387955766 7412: 7408: 7404: 7403:Yan, Tung-Mow 7400: 7394: 7392: 7388: 7384: 7380: 7379:Dirac, P.A.M. 7375: 7373: 7371: 7367: 7363: 7361: 7357: 7352: 7347: 7344: 7340: 7336: 7332: 7329: 7325: 7320: 7317: 7304: 7300: 7294: 7291: 7278: 7274: 7268: 7265: 7260: 7256: 7252: 7248: 7244: 7240: 7236: 7232: 7227: 7222: 7219:(1): 95–102. 7218: 7214: 7213: 7205: 7202: 7197: 7193: 7189: 7187:3-540-42082-7 7183: 7179: 7175: 7169: 7166: 7161: 7155: 7152:. MIT Press. 7151: 7150: 7145: 7139: 7136: 7131: 7129:0-486-26126-3 7125: 7121: 7114: 7111: 7106: 7104:0-7923-2549-4 7100: 7096: 7095: 7090: 7084: 7082: 7080: 7078: 7076: 7072: 7067: 7060: 7057: 7052: 7046: 7042: 7035: 7033: 7031: 7029: 7027: 7025: 7023: 7021: 7019: 7017: 7015: 7013: 7009: 7002: 6981: 6973: 6970: 6967: 6961: 6953: 6949: 6942: 6939: 6930: 6923: 6920: 6905: 6899: 6870: 6846: 6842: 6830: 6827: 6820: 6781: 6778: 6775: 6768: 6744: 6733: 6729: 6725: 6702: 6657: 6654: 6648: 6636: 6606: 6602: 6581: 6578: 6559: 6531: 6528: 6525: 6522: 6519: 6513: 6425: 6367: 6352: 6349: 6345: 6339: 6336: 6329: 6325: 6316: 6313: 6306: 6303: 6294: 6287: 6277: 6273: 6269: 6259: 6255: 6251: 6244: 6241: 6234: 6231: 6228: 6222: 6219: 6215: 6209: 6205: 6198: 6194: 6187: 6184: 6177: 6172: 6169: 6167: 6164: 6162: 6159: 6157: 6154: 6152: 6149: 6147: 6144: 6142: 6139: 6137: 6134: 6132: 6129: 6127: 6124: 6122: 6119: 6117: 6114: 6112: 6109: 6108: 6103: 6101: 6099: 6095: 6091: 6087: 6079: 6077: 6075: 6071: 6070:Eugene Wigner 6068:According to 6066: 6063: 6055: 6039: 6014: 6010: 5984: 5971: 5952: 5948: 5922: 5918: 5889: 5886: 5880: 5877: 5874: 5869: 5854: 5850: 5839: 5835: 5821: 5817: 5811: 5807: 5801: 5797: 5791: 5787: 5783: 5775: 5771: 5762: 5752: 5748: 5739: 5735: 5729: 5725: 5721: 5715: 5703: 5698: 5693: 5691: 5686: 5681: 5676: 5674: 5658: 5650: 5646: 5630: 5626: 5602: 5598: 5586: 5582: 5571: 5567: 5561: 5557: 5553: 5550: 5541: 5527: 5507: 5504: 5501: 5493: 5477: 5469: 5465: 5461: 5457: 5453: 5448: 5432: 5428: 5419: 5418:partial trace 5401: 5397: 5374: 5370: 5361: 5343: 5339: 5335: 5330: 5326: 5316: 5313: 5309: 5304: 5302: 5298: 5294: 5290: 5284: 5276: 5274: 5272: 5268: 5263: 5261: 5257: 5253: 5249: 5244: 5229: 5222: 5210: 5206: 5202: 5199: 5194: 5190: 5186: 5182: 5174: 5169: 5165: 5161: 5158: 5153: 5147: 5137: 5133: 5128: 5120: 5116: 5112: 5108: 5087: 5084: 5079: 5074: 5070: 5066: 5061: 5056: 5052: 5048: 5043: 5031: 5027: 5018: 5013: 5001: 4997: 4967: 4963: 4959: 4955: 4949: 4945: 4941: 4936: 4932: 4918: 4914: 4910: 4906: 4900: 4896: 4892: 4887: 4883: 4873: 4857: 4853: 4830: 4826: 4802: 4792: 4788: 4784: 4778: 4768: 4764: 4740: 4712: 4699: 4693: 4685: 4683: 4669: 4649: 4629: 4609: 4584: 4581: 4561: 4558: 4555: 4552: 4542: 4529: 4516: 4513: 4502: 4492: 4488: 4465: 4455: 4452: 4445: 4429: 4426: 4423: 4415: 4396: 4383: 4382: 4377: 4371: 4363: 4361: 4348: 4321: 4310: 4306: 4302: 4299: 4293: 4265: 4210: 4207: 4202: 4181: 4165: 4161: 4157: 4135: 4114: 4079: 4078: 4057: 4044: 4043: 4042:wave function 4026: 4020: 4004: 3990: 3967: 3954: 3898: 3897: 3891: 3886: 3875: 3852: 3838: 3831: 3827: 3805: 3801: 3785: 3772: 3769: 3764: 3759: 3754: 3750: 3746: 3739: 3735: 3714: 3711: 3708: 3702: 3694: 3668: 3655: 3650: 3633: 3622: 3618: 3610: 3605: 3601: 3592: 3570: 3566: 3551: 3532: 3519: 3514: 3488: 3484: 3472: 3468: 3462: 3458: 3454: 3448: 3420: 3389: 3385: 3370: 3366: 3362: 3361:Hilbert space 3354: 3352: 3350: 3345: 3339: 3337: 3333: 3327: 3322: 3316: 3310: 3307: 3303: 3299: 3295: 3291: 3286: 3272: 3269: 3264: 3260: 3251: 3233: 3229: 3203: 3199: 3194: 3191: 3188: 3183: 3179: 3174: 3171: 3167: 3164: 3161: 3156: 3152: 3148: 3144: 3139: 3135: 3131: 3120: 3112: 3099: 3088: 3084: 3079: 3074: 3063: 3060: 3056: 3051: 3047: 3042: 3037: 3024: 3011: 3007: 3003: 2997: 2989: 2987: 2985: 2981: 2977: 2976: 2971: 2966: 2950: 2947: 2944: 2941: 2938: 2935: 2932: 2929: 2926: 2923: 2920: 2917: 2914: 2911: 2908: 2895: 2888: 2884: 2879: 2874: 2870: 2866: 2861: 2857: 2852: 2846: 2842: 2838: 2833: 2829: 2825: 2821: 2817: 2813: 2807: 2799: 2775: 2771: 2760: 2756: 2743: 2739: 2721: 2708: 2704: 2683: 2657: 2644: 2640: 2636: 2615: 2604: 2585: 2572: 2569: 2565: 2561: 2558: 2542: 2519: 2506: 2505: 2504: 2502: 2501: 2496: 2492: 2488: 2484: 2478: 2470: 2468: 2466: 2462: 2458: 2454: 2450: 2434: 2411: 2396: 2392: 2376: 2356: 2348: 2343: 2341: 2337: 2333: 2332:Hilbert space 2329: 2323: 2315: 2312: 2304: 2302: 2300: 2299:Dirac picture 2296: 2292: 2287: 2268: 2252: 2244: 2240: 2234: 2230: 2226: 2217: 2198: 2192: 2188: 2181: 2177: 2172: 2167: 2158: 2156: 2154: 2150: 2146: 2140: 2138: 2133: 2127: 2121: 2115: 2109: 2103: 2097: 2091: 2085: 2079: 2074: 2071:Consider two 2069: 2067: 2063: 2059: 2055: 2050: 2048: 2038: 2034: 2027: 2023: 2018: 2013: 2010: 1991: 1983: 1969: 1953: 1926: 1922: 1899: 1885: 1880: 1878: 1874: 1870: 1866: 1862: 1858: 1854: 1850: 1846: 1842: 1838: 1833: 1821: 1820:superposition 1805: 1794: 1786: 1782: 1778: 1770: 1756: 1752: 1747: 1743: 1740: 1737: 1728: 1724: 1723:singlet state 1720: 1716: 1712: 1696: 1693: 1690: 1681: 1679: 1670: 1668: 1666: 1649: 1641: 1625: 1617: 1613: 1607: 1603: 1599: 1590: 1571: 1567: 1563: 1558: 1556: 1552: 1548: 1543: 1539: 1535: 1534: 1529: 1525: 1521: 1520:Hilbert space 1518: 1515: 1511: 1506: 1501: 1496: 1482: 1462: 1454: 1433: 1403: 1378: 1375: 1372: 1367: 1357: 1349: 1344: 1334: 1306: 1303: 1300: 1289: 1285: 1279: 1275: 1270: 1267: 1262: 1258: 1253: 1249: 1244: 1240: 1236: 1235:hydrogen atom 1232: 1228: 1224: 1220: 1216: 1208: 1204: 1197: 1195: 1192: 1188: 1184: 1168: 1165: 1162: 1159: 1156: 1148: 1144: 1140: 1135: 1134:Wave function 1127: 1125: 1123: 1119: 1114: 1112: 1108: 1100: 1098: 1096: 1091: 1089: 1085: 1081: 1076: 1070: 1062: 1060: 1058: 1041: 1030: 1022: 1020: 1016: 1014: 1010: 1006: 998: 996: 994: 990: 986: 982: 977: 974: 970: 962: 960: 958: 954: 950: 946: 942: 938: 930: 926: 923: 920: 919: 918: 915: 912: 908: 904: 903:quantum state 900: 888: 883: 881: 876: 874: 869: 868: 866: 865: 857: 854: 852: 849: 847: 844: 842: 839: 837: 834: 832: 829: 827: 824: 822: 819: 817: 814: 812: 809: 807: 804: 802: 799: 797: 794: 792: 789: 787: 784: 782: 779: 777: 774: 772: 769: 767: 764: 762: 759: 757: 754: 752: 749: 747: 744: 742: 739: 737: 734: 732: 729: 727: 724: 722: 719: 717: 714: 712: 709: 707: 704: 702: 699: 697: 694: 692: 689: 687: 684: 682: 679: 677: 674: 672: 669: 667: 664: 662: 659: 657: 654: 652: 649: 647: 644: 642: 639: 637: 634: 632: 629: 628: 621: 620: 613: 610: 608: 605: 603: 600: 598: 595: 593: 590: 588: 587:Quantum chaos 585: 583: 580: 578: 575: 573: 570: 568: 565: 564: 558: 557: 549: 546: 544: 543:Transactional 541: 539: 536: 534: 533:Quantum logic 531: 529: 526: 524: 521: 515: 512: 511: 510: 507: 506: 505: 502: 500: 497: 495: 492: 490: 487: 485: 482: 480: 477: 476: 472: 467: 466: 458: 455: 453: 450: 448: 445: 443: 440: 438: 435: 434: 427: 426: 418: 415: 413: 410: 408: 405: 403: 400: 398: 395: 393: 390: 389: 385: 382: 381: 375: 374: 366: 363: 361: 358: 356: 353: 352: 346: 343: 342: 341: 338: 337: 333: 330: 328: 325: 323: 320: 318: 315: 313: 310: 308: 305: 303: 300: 298: 295: 293: 290: 288: 285: 284: 277: 276: 266: 263: 262: 261: 260:Wave function 258: 256: 253: 251: 248: 246: 243: 241: 240:Superposition 238: 236: 233: 231: 228: 226: 223: 221: 218: 216: 213: 211: 208: 206: 203: 201: 198: 197: 190: 189: 181: 178: 176: 173: 172: 168: 165: 163: 160: 158: 155: 154: 148: 147: 142: 139: 137: 134: 132: 129: 128: 127: 126: 122: 89: 83: 66: 63: 59: 51: 44: 43: 40: 36: 32: 31: 19: 8238:Quantum mind 8150:Franck–Hertz 8012:Klein–Gordon 7961:Formulations 7954:Formulations 7902: 7883:Interference 7873:Entanglement 7851:Ground state 7846:Energy level 7819:Fundamentals 7783:Introduction 7726: 7723:Ć»yczkowski K 7715: 7713:at Caltech. 7711:Physics 219 7708: 7693:. Springer. 7690: 7676: 7653: 7644: 7637: 7626:p.8–18 7621: 7589: 7585: 7579: 7569: 7553: 7543: 7537: 7514: 7505: 7486: 7480: 7461: 7455: 7442: 7406: 7382: 7359: 7355: 7346: 7338: 7330: 7327: 7319: 7307:. Retrieved 7303:the original 7293: 7281:. Retrieved 7277:the original 7267: 7216: 7210: 7204: 7177: 7168: 7148: 7138: 7119: 7113: 7092: 7089:Peres, Asher 7065: 7059: 7040: 6928: 6922: 6656: 6646: 6634: 6604: 6600: 6580: 6351: 6338: 6327: 6323: 6315: 6305: 6292: 6285: 6275: 6271: 6267: 6257: 6253: 6249: 6243: 6233: 6221: 6213: 6207: 6203: 6196: 6192: 6186: 6126:Ground state 6116:Bloch sphere 6083: 6067: 6058: 6053: 5969: 5705:is given by 5701: 5694: 5684: 5677: 5628: 5624: 5542: 5492:purification 5467: 5463: 5459: 5455: 5451: 5449: 5317: 5305: 5292: 5288: 5286: 5277:Mixed states 5264: 5255: 5245: 4874: 4695: 4622:at any time 4413: 4379: 4373: 4253:, the state 4076: 4075:probability 4040: 3895: 3892: 3881: 3870: 3833: 3786: 3653: 3651: 3549: 3509: 3359:As with any 3358: 3343: 3340: 3325: 3314: 3311: 3305: 3301: 3287: 3249: 3115: 3113: 3001: 2999: 2974: 2967: 2893: 2886: 2877: 2869:half-integer 2859: 2850: 2831: 2809: 2741: 2602: 2567: 2563: 2557:mathematical 2556: 2535:(where the " 2498: 2480: 2460: 2452: 2448: 2344: 2325: 2288: 2190: 2186: 2179: 2175: 2165: 2162: 2149:entanglement 2144: 2141: 2136: 2131: 2125: 2119: 2113: 2107: 2101: 2095: 2089: 2083: 2077: 2070: 2065: 2061: 2057: 2053: 2051: 2036: 2032: 2025: 2021: 2016: 2014: 2008: 1970: 1881: 1851:, which are 1834: 1682: 1674: 1561: 1559: 1550: 1531: 1504: 1497: 1277: 1273: 1268: 1260: 1251: 1242: 1214: 1212: 1186: 1182: 1137: 1122:vector space 1115: 1106: 1104: 1092: 1083: 1079: 1074: 1072: 1032: 1023:Measurements 1017: 1002: 978: 966: 941:mixed states 934: 916: 902: 896: 442:Klein–Gordon 378:Formulations 234: 215:Energy level 210:Entanglement 193:Fundamentals 180:Interference 131:Introduction 8496:EPR paradox 8276:Quantum bus 8145:Double-slit 8123:Experiments 8089:Many-worlds 8027:Schrödinger 7991:Phase space 7981:Schrödinger 7971:Interaction 7928:Uncertainty 7898:Nonlocality 7893:Measurement 7888:Decoherence 7878:Hamiltonian 7309:January 24, 7283:November 9, 6146:PBR theorem 4444:compact set 4442:there is a 4381:bound state 3830:eigenvalues 3826:eigenstates 3591:orthonormal 2487:dual spaces 2340:unit sphere 1914:. A number 1865:measurement 1547:eigenvector 1542:eigenvalues 1530:called the 1271:-component 1219:eigenstates 1215:pure states 1084:mixed state 911:measurement 831:von Neumann 816:Schrödinger 592:EPR paradox 523:Many-worlds 457:Schrödinger 412:Schrödinger 407:Phase-space 397:Interaction 302:Double-slit 280:Experiments 255:Uncertainty 225:Nonlocality 220:Measurement 205:Decoherence 175:Hamiltonian 18:Eigenstates 8424:Extensions 8258:Technology 8104:Relational 8055:Copenhagen 7966:Heisenberg 7913:Tunnelling 7776:Background 7434:Lev Landau 7050:0486409244 7003:References 6641:′ − 6611:′ − 6344:p. 31 6090:C*-algebra 6074:Lev Landau 6054:incoherent 4698:superposed 4480:such that 4416:for every 4368:See also: 3654:normalized 3408:, any ket 2639:dual space 2605:, denoted 2495:Paul Dirac 2320:See also: 2309:See also: 1551:eigenstate 1533:observable 1264:, and the 1080:pure state 1075:eigenstate 943:, or into 826:Sommerfeld 741:Heisenberg 736:Gutzwiller 676:de Broglie 624:Scientists 538:Relational 489:Copenhagen 392:Heisenberg 250:Tunnelling 151:Background 8130:Bell test 8000:Equations 7826:Born rule 7614:125732617 7546:, page 39 7519:MIT Press 7362:: 580–590 7251:0894-9875 7196:318268606 6974:ρ 6971:⁡ 6950:ρ 6943:⁡ 6903:∞ 6897:⟩ 6879:⟨ 6847:− 6831:δ 6825:⟩ 6802:⟨ 6773:⟩ 6750:⟨ 6726:∫ 6706:⟩ 6703:ψ 6678:⟩ 6647:df′ 6563:⟩ 6560:ψ 6489:⟩ 6459:⟩ 6429:⟩ 6426:ψ 6401:⟩ 6371:⟩ 6368:ψ 6020:⟩ 6011:ψ 5928:⟩ 5919:α 5887:ρ 5881:⁡ 5860:⟩ 5851:ψ 5836:α 5832:⟨ 5798:∑ 5788:∑ 5781:⟩ 5772:ψ 5749:ψ 5745:⟨ 5726:∑ 5719:⟩ 5713:⟨ 5673:formalism 5656:⟩ 5647:ψ 5599:ψ 5595:⟨ 5592:⟩ 5583:ψ 5558:∑ 5551:ρ 5505:⊗ 5360:entangled 5336:⊗ 5312:entangled 5260:coherence 5226:⟩ 5223:β 5211:α 5207:θ 5200:− 5195:β 5191:θ 5170:α 5162:− 5151:⟩ 5148:α 5138:α 5121:α 5117:θ 5075:β 5057:α 5032:β 5002:α 4968:β 4964:θ 4950:β 4937:β 4919:α 4915:θ 4901:α 4888:α 4858:β 4831:α 4806:⟩ 4803:β 4793:β 4782:⟩ 4779:α 4769:α 4744:⟩ 4741:β 4716:⟩ 4713:α 4585:∈ 4562:ε 4559:− 4553:≥ 4503:ϕ 4489:∫ 4456:⊂ 4424:ε 4400:⟩ 4397:ϕ 4346:⟩ 4322:ψ 4303:∫ 4297:⟩ 4294:ψ 4269:⟩ 4266:ψ 4241:⟩ 4182:ψ 4158:∫ 4115:ψ 4061:⟩ 4058:ψ 4024:⟩ 4021:ψ 4008:⟨ 4005:≡ 3991:ψ 3971:⟩ 3968:ψ 3917:⟩ 3856:⟩ 3853:ψ 3812:⟩ 3736:∑ 3706:⟩ 3703:ψ 3695:ψ 3692:⟨ 3672:⟩ 3669:ψ 3637:⟩ 3634:ψ 3614:⟨ 3577:⟩ 3536:⟩ 3533:ψ 3495:⟩ 3459:∑ 3452:⟩ 3449:ψ 3424:⟩ 3421:ψ 3396:⟩ 3334:they are 3265:ν 3234:ν 3204:ν 3189:− 3184:ν 3172:… 3157:ν 3149:− 3140:ν 3132:− 3097:⟩ 3061:… 3025:ψ 2942:− 2933:… 2918:− 2909:− 2845:Lie group 2826:) as the 2781:⟩ 2772:ψ 2757:ψ 2753:⟨ 2725:⟩ 2722:ψ 2703:transpose 2684:ψ 2681:⟨ 2661:⟩ 2658:ψ 2616:ψ 2613:⟨ 2589:⟩ 2586:ψ 2573:Each ket 2543:ψ 2523:⟩ 2520:ψ 2457:half-line 2274:⟩ 2265:Φ 2231:∑ 2224:⟩ 2212:Ψ 2117:and then 1992:σ 1987:⟩ 1981:⟨ 1950:Φ 1896:Φ 1843:over the 1783:− 1741:ψ 1721:) by the 1711:Hermitian 1694:× 1647:⟩ 1638:Φ 1604:∑ 1597:⟩ 1585:Ψ 1514:separable 1483:β 1463:α 1434:β 1404:α 1358:β 1335:α 1307:β 1301:α 856:Zeilinger 701:Ehrenfest 430:Equations 107:⟩ 104:Ψ 93:^ 81:⟩ 78:Ψ 55:ℏ 8534:Category 8519:Category 8313:Timeline 8065:Ensemble 8045:Bayesian 7938:Collapse 7810:Glossary 7793:Timeline 7725:(2006). 7689:(1987). 7561:(1962). 7513:(2022). 7440:(1965). 7405:(2003). 7381:(1958). 7351:Bohr, N. 7328:Z. Phys. 7259:15995449 7176:(2001). 7091:(1995). 6843:′ 6821:′ 6769:′ 6745:′ 6620:⟨ 6330:⟩ 6322:⟨ 6104:See also 5358:with an 4574:for all 3953:spinless 3336:massless 3298:fermions 2832:discrete 2742:brackets 2087:, where 1795:⟩ 1779:⟩ 1744:⟩ 1568:, this 1528:operator 1524:particle 1451:are the 1231:electron 1143:momentum 1013:operator 781:Millikan 706:Einstein 691:Davisson 646:Blackett 631:Aharonov 499:Ensemble 479:Bayesian 384:Overview 265:Collapse 245:Symmetry 136:Glossary 8472:Related 8451:History 8190:Science 8022:Rydberg 7788:History 7594:Bibcode 7231:Bibcode 6591:′ 6171:W state 5973:, and " 4077:density 3656:states 3363:, if a 3321:photons 3012:, e.g. 2873:massive 2865:integer 2843:of the 2837:spinors 2635:adjoint 2463:in the 2393:in the 1827:⁄ 1678:mixture 1517:complex 1510:vectors 1290:vector 1288:complex 1229:of the 939:versus 821:Simmons 811:Rydberg 776:Moseley 756:Kramers 746:Hilbert 731:Glauber 726:Feynman 711:Everett 681:Compton 452:Rydberg 141:History 8165:Popper 7697:  7666:  7612:  7542:Blum, 7525:  7493:  7468:  7413:  7356:Nature 7257:  7249:  7194:  7184:  7156:  7126:  7101:  7047:  6794:i.e., 6624:| 6326:| 6298:> 0 6238:first. 5905:where 5622:where 5452:cannot 4929:  4926:  3888:| 3879:| 3828:(with 3507:where 3332:vacuum 3294:bosons 3250:ν 3221:where 2970:vector 2881:, its 2347:scalar 1391:where 1255:, the 1246:, the 851:Zeeman 846:Wigner 796:Planck 766:Landau 751:Jordan 402:Matrix 332:Popper 8075:Local 8017:Pauli 8007:Dirac 7610:S2CID 7566:(PDF) 7447:(PDF) 7255:S2CID 7221:arXiv 6413:, so 6310:ket." 6291:> 6178:Notes 6088:on a 5680:trace 5420:over 5295:is a 4700:. If 3365:basis 3317:= 1/2 2459:, or 1839:in a 1715:trace 1512:in a 1233:in a 1118:below 1088:below 806:Raman 791:Pauli 786:Onnes 721:Fermi 696:Debye 686:Dirac 651:Bloch 641:Bethe 509:Local 447:Pauli 437:Dirac 235:State 7695:ISBN 7664:ISBN 7523:ISBN 7491:ISBN 7466:ISBN 7411:ISBN 7311:2012 7285:2021 7247:ISSN 7192:OCLC 7182:ISBN 7154:ISBN 7124:ISBN 7099:ISBN 7045:ISBN 6631:), " 6441:and 6265:and 6201:and 6096:and 5940:and 5458:(or 4845:and 4728:and 4427:> 4281:is: 3824:are 3516:are 3010:spin 3008:and 2810:The 2800:Spin 2566:and 2489:and 2453:line 2336:norm 2081:and 1562:does 1498:The 1475:and 1421:and 1266:spin 973:real 937:pure 901:, a 841:Wien 836:Weyl 801:Rabi 771:Laue 761:Lamb 716:Fock 671:Bose 666:Born 661:Bohr 656:Bohm 636:Bell 7602:doi 7360:121 7239:doi 6867:(a 6649:= 1 6586:∫ Κ 6214:not 5682:of 5468:and 5303:). 4102:is 3877:is 3328:= 1 2896:+ 1 2709:of 2603:bra 2568:ket 2564:bra 2461:ray 2449:ray 2427:of 2391:ray 2017:all 1837:ray 1455:of 955:in 897:In 8536:: 7731:, 7685:; 7662:. 7658:. 7608:. 7600:. 7590:45 7588:. 7521:. 7436:; 7425:^ 7401:; 7390:^ 7369:^ 7331:43 7253:. 7245:. 7237:. 7229:. 7217:19 7215:. 7190:. 7074:^ 7011:^ 6968:Tr 6940:Tr 6651:". 6645:) 6633:∫ 6603:= 6601:dq 6599:* 6270:= 6252:= 6076:. 5975:tr 5878:tr 5540:. 5447:. 5287:A 4682:. 4211:1. 3773:1. 3649:. 3319:, 2467:. 2301:. 2184:, 2075:, 2049:. 1729:: 1667:. 1495:. 1090:. 1059:. 959:. 7761:e 7754:t 7747:v 7672:. 7616:. 7604:: 7596:: 7548:. 7531:. 7499:. 7474:. 7419:. 7364:. 7313:. 7287:. 7261:. 7241:: 7233:: 7223:: 7198:. 7162:. 7132:. 7107:. 7053:. 6982:2 6978:) 6965:( 6962:= 6959:) 6954:2 6946:( 6929:ρ 6906:. 6900:= 6893:r 6888:| 6883:r 6855:) 6851:r 6839:r 6834:( 6828:= 6817:r 6811:| 6806:r 6782:, 6779:1 6776:= 6765:r 6759:| 6754:r 6741:r 6734:3 6730:d 6699:| 6674:r 6669:| 6643:f 6639:f 6637:( 6635:ÎŽ 6626:f 6622:f 6615:) 6613:f 6609:f 6607:( 6605:ÎŽ 6596:f 6593:Κ 6589:f 6556:| 6535:) 6532:z 6529:, 6526:y 6523:, 6520:x 6517:( 6514:= 6510:r 6485:r 6480:| 6455:r 6450:| 6422:| 6397:r 6392:| 6364:| 6328:A 6324:B 6300:. 6296:1 6293:t 6289:2 6286:t 6281:) 6279:2 6276:t 6274:( 6272:P 6268:B 6263:) 6261:1 6258:t 6256:( 6254:Q 6250:A 6210:) 6208:t 6206:( 6204:P 6199:) 6197:t 6195:( 6193:Q 6061:s 6059:p 6040:s 6015:s 6006:| 5985:i 5970:A 5953:i 5949:a 5923:i 5914:| 5893:) 5890:A 5884:( 5875:= 5870:2 5865:| 5855:s 5846:| 5840:i 5828:| 5822:i 5818:a 5812:s 5808:p 5802:i 5792:s 5784:= 5776:s 5767:| 5763:A 5759:| 5753:s 5740:s 5736:p 5730:s 5722:= 5716:A 5702:A 5685:ρ 5659:. 5651:s 5642:| 5629:s 5625:p 5609:| 5603:s 5587:s 5578:| 5572:s 5568:p 5562:s 5554:= 5528:K 5508:K 5502:H 5478:H 5464:ρ 5433:2 5429:H 5402:1 5398:H 5375:2 5371:H 5344:2 5340:H 5331:1 5327:H 5230:) 5219:| 5203:i 5187:i 5183:e 5175:2 5166:A 5159:1 5154:+ 5144:| 5134:A 5129:( 5113:i 5109:e 5088:1 5085:= 5080:2 5071:A 5067:+ 5062:2 5053:A 5049:= 5044:2 5039:| 5028:c 5023:| 5019:+ 5014:2 5009:| 4998:c 4993:| 4960:i 4956:e 4946:A 4942:= 4933:c 4911:i 4907:e 4897:A 4893:= 4884:c 4854:c 4827:c 4799:| 4789:c 4785:+ 4775:| 4765:c 4737:| 4709:| 4670:K 4650:1 4630:t 4610:K 4589:R 4582:t 4556:1 4549:r 4543:3 4538:d 4530:2 4525:| 4520:) 4517:t 4514:, 4510:r 4506:( 4499:| 4493:K 4466:3 4461:R 4453:K 4430:0 4393:| 4349:. 4342:r 4337:| 4333:) 4329:r 4325:( 4317:r 4311:3 4307:d 4300:= 4290:| 4262:| 4237:r 4232:| 4208:= 4203:2 4198:| 4193:) 4189:r 4185:( 4178:| 4172:r 4166:3 4162:d 4136:2 4131:| 4126:) 4122:r 4118:( 4111:| 4089:r 4054:| 4027:. 4017:| 4012:r 4002:) 3998:r 3994:( 3964:| 3938:r 3913:r 3908:| 3884:i 3882:c 3873:i 3871:k 3849:| 3836:i 3834:k 3806:i 3802:k 3796:| 3770:= 3765:2 3760:| 3755:i 3751:c 3747:| 3740:i 3715:, 3712:1 3709:= 3699:| 3665:| 3630:| 3623:i 3619:k 3611:= 3606:i 3602:c 3571:i 3567:k 3561:| 3529:| 3512:i 3510:c 3489:i 3485:k 3479:| 3473:i 3469:c 3463:i 3455:= 3445:| 3417:| 3390:i 3386:k 3380:| 3344:N 3326:S 3315:S 3306:N 3302:N 3273:0 3270:= 3261:S 3230:S 3209:} 3200:S 3195:, 3192:1 3180:S 3175:, 3168:, 3165:1 3162:+ 3153:S 3145:, 3136:S 3129:{ 3118:Îœ 3116:m 3100:. 3094:) 3089:N 3085:m 3080:, 3075:N 3070:r 3064:; 3057:; 3052:1 3048:m 3043:, 3038:1 3033:r 3028:( 3021:| 3002:N 2975:C 2954:} 2951:S 2948:, 2945:1 2939:S 2936:, 2930:, 2927:1 2924:+ 2921:S 2915:, 2912:S 2906:{ 2894:S 2892:2 2887:m 2878:S 2860:ħ 2851:S 2824:T 2822:· 2820:L 2818:· 2816:M 2793:. 2776:2 2767:| 2761:1 2737:. 2718:| 2688:| 2654:| 2620:| 2582:| 2516:| 2435:H 2415:) 2412:H 2409:( 2405:P 2377:H 2357:H 2269:n 2260:| 2256:) 2253:t 2250:( 2245:n 2241:C 2235:n 2227:= 2221:) 2218:t 2215:( 2208:| 2193:) 2191:t 2189:( 2187:Q 2182:) 2180:t 2178:( 2176:P 2166:σ 2132:B 2126:A 2120:B 2114:A 2108:B 2102:B 2096:B 2090:A 2084:B 2078:A 2066:A 2062:A 2058:A 2043:t 2039:) 2037:t 2035:( 2033:P 2028:) 2026:t 2024:( 2022:Q 2009:A 1984:A 1954:n 1927:n 1923:P 1900:n 1829:2 1825:1 1806:, 1801:) 1787:| 1771:| 1765:( 1757:2 1753:1 1748:= 1738:| 1697:2 1691:2 1650:. 1642:n 1633:| 1629:) 1626:t 1623:( 1618:n 1614:C 1608:n 1600:= 1594:) 1591:t 1588:( 1581:| 1505:t 1438:| 1430:| 1408:| 1400:| 1379:, 1376:1 1373:= 1368:2 1363:| 1354:| 1350:+ 1345:2 1340:| 1331:| 1310:) 1304:, 1298:( 1278:z 1274:s 1269:z 1261:m 1252:ℓ 1243:n 1169:z 1166:, 1163:y 1160:, 1157:x 1042:x 931:. 886:e 879:t 872:v 100:| 90:H 84:= 74:| 67:t 64:d 60:d 52:i 20:)

Index

Eigenstates
Quantum mechanics
Schrödinger equation
Introduction
Glossary
History
Classical mechanics
Old quantum theory
Bra–ket notation
Hamiltonian
Interference
Complementarity
Decoherence
Entanglement
Energy level
Measurement
Nonlocality
Quantum number
State
Superposition
Symmetry
Tunnelling
Uncertainty
Wave function
Collapse
Bell's inequality
CHSH inequality
Davisson–Germer
Double-slit
Elitzur–Vaidman

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