Multilinear Formulas and Skepticism of Quantum Computing
... (A): QC’s can’t be built for fundamental reason—Levin’s arguments (1) Analogy to unit-cost arithmetic model (2) Error-correction and fault-tolerance address only relative error in amplitudes, not absolute (3) “We have never seen a physical law valid to over a dozen decimals” (4) If a quantum comput ...
... (A): QC’s can’t be built for fundamental reason—Levin’s arguments (1) Analogy to unit-cost arithmetic model (2) Error-correction and fault-tolerance address only relative error in amplitudes, not absolute (3) “We have never seen a physical law valid to over a dozen decimals” (4) If a quantum comput ...
Neitzke: What is a BPS state?
... continuous deformations of the G̃-representation H1 . The trouble is with our definition of H1 itself. We have loosely described it as the space of states which occur discretely in H, as opposed to the multiparticle states which occur in direct integrals. One might wonder whether it is really possib ...
... continuous deformations of the G̃-representation H1 . The trouble is with our definition of H1 itself. We have loosely described it as the space of states which occur discretely in H, as opposed to the multiparticle states which occur in direct integrals. One might wonder whether it is really possib ...
Square Root of an Operator - Information Sciences and Computing
... Schrödinger equation to incorporate the electron spin. So the operator (3) adopts the form = ! + # , and in quantum mechanics the Laplacian operator is related to the square of the linear momentum operator, then from (4) it is natural to think that operators of the type (quadratic in $̂ )1/2 can be ...
... Schrödinger equation to incorporate the electron spin. So the operator (3) adopts the form = ! + # , and in quantum mechanics the Laplacian operator is related to the square of the linear momentum operator, then from (4) it is natural to think that operators of the type (quadratic in $̂ )1/2 can be ...
Δk/k
... When the electron is localized such that one knows which slit it passes, then the electron is so much disturbed that interference is lost. In this way knowledge what is going on under the cover of uncertainty is principally prevented.] These strange phenomena reappear for angular momentum (both orbi ...
... When the electron is localized such that one knows which slit it passes, then the electron is so much disturbed that interference is lost. In this way knowledge what is going on under the cover of uncertainty is principally prevented.] These strange phenomena reappear for angular momentum (both orbi ...
QUANTUM HETERODOXY: REALISM AT THE PLANK LENGTH Q
... The operators in (1), (2) and (3) are rather misleadingly named for they do not give position, momentum or energy of any system—rather they give the expectation values for these quantities. Thus they are mean values and not necessarily what one will find if one makes a measurement. This fact was obs ...
... The operators in (1), (2) and (3) are rather misleadingly named for they do not give position, momentum or energy of any system—rather they give the expectation values for these quantities. Thus they are mean values and not necessarily what one will find if one makes a measurement. This fact was obs ...
Fall 2004 Colloquium Series Physics Department University of Oregon 3:30 Thursdays, 100 Willamette
... post-Hartree-Fock restoration of the broken symmetries via projection techniques is reviewed for the case of two-dimensional semiconductor quantum dots (QD's; often referred to as artificial atoms). The general principles of the two-step method can be traced to nuclear theory [2] and quantum chemist ...
... post-Hartree-Fock restoration of the broken symmetries via projection techniques is reviewed for the case of two-dimensional semiconductor quantum dots (QD's; often referred to as artificial atoms). The general principles of the two-step method can be traced to nuclear theory [2] and quantum chemist ...
Beables for Quantum Electrodynamics
... lead to any supra-luminal signaling. Now, the widespread claim is that those interpretations are ruled out by Bell’s inequality ([2], chap 7) and the experiments that have been carried out later. If fact local ones are ruled out, but since non-locality is commonly claimed to be unacceptable (even we ...
... lead to any supra-luminal signaling. Now, the widespread claim is that those interpretations are ruled out by Bell’s inequality ([2], chap 7) and the experiments that have been carried out later. If fact local ones are ruled out, but since non-locality is commonly claimed to be unacceptable (even we ...
Quantum Computation
... Solution #1: wait for a few years for a better (classical) computer. ◦ Problem: Today: L< 1μm. (L-Transistor size) Quantum effects become important: L~λ~nm. (λ-de Broglie wavelength of electrons). Individual atom size: L~a0~Ǻ. ...
... Solution #1: wait for a few years for a better (classical) computer. ◦ Problem: Today: L< 1μm. (L-Transistor size) Quantum effects become important: L~λ~nm. (λ-de Broglie wavelength of electrons). Individual atom size: L~a0~Ǻ. ...
PPT
... fully describe whether interference effects will be found in hypothetical experiments with large-scale quantum coherence. • The formal Copenhagen approach avoids that problem by saying that the wave function is a non-existent entity to which the linear wave function applies exactly, in between exper ...
... fully describe whether interference effects will be found in hypothetical experiments with large-scale quantum coherence. • The formal Copenhagen approach avoids that problem by saying that the wave function is a non-existent entity to which the linear wave function applies exactly, in between exper ...
Time in Quantum Theory
... spatial metric as a dynamical object, is itself quantized [1] – as required for consistency (see IV). The thereby achieved 'quantization of time' does not necessarily lead to a discretization of time – just as the quantization of free motion does not require a discretization of space. On the other h ...
... spatial metric as a dynamical object, is itself quantized [1] – as required for consistency (see IV). The thereby achieved 'quantization of time' does not necessarily lead to a discretization of time – just as the quantization of free motion does not require a discretization of space. On the other h ...
is the “quantum number”
... In a magnetic field, the spectral lines are split into several very closely spaced lines. This splitting, known as the Zeeman effect, demonstrates that the atoms energy levels are split. This means that, in magnetic field, the energy of state depend not only on principal quantum number, n but also o ...
... In a magnetic field, the spectral lines are split into several very closely spaced lines. This splitting, known as the Zeeman effect, demonstrates that the atoms energy levels are split. This means that, in magnetic field, the energy of state depend not only on principal quantum number, n but also o ...
A spectral theoretic approach to quantum
... extension of this classical definition. A quantum Hamiltonian is said to be integrable when there exist n `functionally independent' linear operators which commute among them and with the Hamiltonian. • The definition of dimension of a quantum system has been proposed by Zhang et al. (1989). In 1990 ...
... extension of this classical definition. A quantum Hamiltonian is said to be integrable when there exist n `functionally independent' linear operators which commute among them and with the Hamiltonian. • The definition of dimension of a quantum system has been proposed by Zhang et al. (1989). In 1990 ...
The Born rule and its interpretation
... Upon the identifications explained above, the Born probability measure then comes out to be just the restriction of the total state on A to the ‘classical’ subalgebra D thereof that Bohr calls for. This account does not provide a derivation of the Born rule from first principles, but it does clarif ...
... Upon the identifications explained above, the Born probability measure then comes out to be just the restriction of the total state on A to the ‘classical’ subalgebra D thereof that Bohr calls for. This account does not provide a derivation of the Born rule from first principles, but it does clarif ...
Quantum Discord: A Measure of the Quantumness of Correlations
... interrogate just one part of a composite system and discover its state while leaving the overall density matrix (as perceived by observers that do not have access to the measurement outcome) unaltered. A general separable rS ,A does not allow for such insensitivity to measurements: Information can b ...
... interrogate just one part of a composite system and discover its state while leaving the overall density matrix (as perceived by observers that do not have access to the measurement outcome) unaltered. A general separable rS ,A does not allow for such insensitivity to measurements: Information can b ...
Energy-time entanglement, elements of reality, and local realism Linköping University Post Print
... In 1989 a new interferometric setup was proposed by J. D. Franson [1]. The main intent was to test the possibility of local realist models as a possible description, more complete than quantum mechanics. The sinusoidal interference obtained from the experiment when restricting to coincident events i ...
... In 1989 a new interferometric setup was proposed by J. D. Franson [1]. The main intent was to test the possibility of local realist models as a possible description, more complete than quantum mechanics. The sinusoidal interference obtained from the experiment when restricting to coincident events i ...
... When electrons are confined to a small region of a semiconductor they form a quantum dot, and the energy and the charge on the quantum dot are quantized. It has been possible to study the transmission of electrons through a quantum dot by coupling the states in the dot to external leads via a tunnel ...
Bell's theorem
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Bell's theorem is a ‘no-go theorem’ that draws an important distinction between quantum mechanics (QM) and the world as described by classical mechanics. This theorem is named after John Stewart Bell.In its simplest form, Bell's theorem states:Cornell solid-state physicist David Mermin has described the appraisals of the importance of Bell's theorem in the physics community as ranging from ""indifference"" to ""wild extravagance"". Lawrence Berkeley particle physicist Henry Stapp declared: ""Bell's theorem is the most profound discovery of science.""Bell's theorem rules out local hidden variables as a viable explanation of quantum mechanics (though it still leaves the door open for non-local hidden variables). Bell concluded:Bell summarized one of the least popular ways to address the theorem, superdeterminism, in a 1985 BBC Radio interview: