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1.
Building on Peres’ idea of “Delayed-choice for entanglement swapping” we show that even the degree to which quantum systems
were entangled can be defined after they have been registered and may even not exist any more. This does not arise as a paradox
if the quantum state is viewed as just a representative of information. Moreover such a view gives a natural quantification
of the complementarity between the measure of information about the input state for teleportation and the amount of entanglement
of the resulting swapped entangled state.
PACS Numbers: 03.65.-w,03.65.Ud,03.67.-a
This Paper is Dedicated to Prof. Asher Peres on the Occasion of his 70th Birthday. 相似文献
2.
We tell the tale of the first writing of a partial transpose, without guaranteeing historical authenticity.
Dedicated to Prof. Asher Peres, Haifa, on the occasion of his 70th birthday. 相似文献
3.
There are aspects of privacy theory that are analogous to quantum theory. In particular one can define distillable key and
key cost in parallel to distillable entanglement and entanglement cost. We present here classical privacy theory as a particular
case of information theory with adversaries, where similar general laws hold as in entanglement theory. We place the result
of Renner and Wolf—that intrinsic information is lower bound for key cost—into this general formalism. Then we show that the
question of whether intrinsic information is equal to key cost is equivalent to the question of whether Alice and Bob can
create a distribution product with Eve using IM bits of secret key. We also propose a natural analogue of relative entropy of entanglement in privacy theory and show that
it is equal to the intrinsic information. We also provide a formula analogous to the entanglement of formation for classical
distributions.
It is our pleasure to dedicate this paper to Asher Peres on the occasion of his seventieth birthday. 相似文献
4.
According to the universal entropy bound, the entropy (and hence information capacity) of a complete weakly self-gravitating
physical system can be bounded exclusively in terms of its circumscribing radius and total gravitating energy. The bound’s
correctness is supported by explicit statistical calculations of entropy, gedanken experiments involving the generalized second
law, and Bousso’s covariant holographic bound. On the other hand, it is not always obvious in a particular example how the
system avoids having too many states for given energy, and hence violating the bound. We analyze in detail several purported
counterexamples of this type, and exhibit in each case the mechanism behind the bound’s efficacy.
In memoriam Asher Peres. 相似文献
5.
We investigate the effect of the isotropic velocity-dependent potentials on the bound state energy eigenvalues of the Morse potential for any quantum states. When the velocity-dependent term is used as a constant parameter, ρ(r) = ρ 0, the energy eigenvalues can be obtained analytically by using the Pekeris approximation. When the velocity-dependent term is considered as an harmonic oscillator type, ρ(r) = ρ 0 r 2, we show how to obtain the energy eigenvalues of the Morse potential without any approximation for any n and ℓ quantum states by using numerical calculations. The calculations have been performed for different energy eigenvalues and different numerical values of ρ 0, in order to show the contribution of the velocity-dependent potential on the energy eigenvalues of the Morse potential. 相似文献
6.
Bao-Xi Sun Hua-Xing Chen E. Oset 《The European Physical Journal A - Hadrons and Nuclei》2011,47(10):127
The ρρN and ρρΔ three-body systems have been studied within the framework of the fixed center approximation of Faddeev equation. The ρρ interaction in isospin I = 0 , spin S = 2 is strongly attractive, and so are the N ρ, ρΔ interactions. This leads to bound states of both ρρN and ρρΔ. We find peaks of the modulus squared of the scattering matrix around 2227 MeV for ρρN, and 2372 MeV for ρρΔ. Yet, the strength of the peak for the ρρN amplitude is much smaller than for ρρΔ, weakening the case for a ρρN bound state, or a dominant ρρN component. A discussion is made on how these states can be searched for in present programs looking for multimeson final
states in different reactions. 相似文献
7.
One of the endearing traits of Asher Peres is that when somebody publishes something he knows to be wrong, he does not bother
to refute it, even if the paper criticizes his own work. Life is too brief for such frivolity. As a small 70th birthday present
I would like to answer one such recent attack. It’s not much of a present, since Asher will not read my paper. Why should
he? He already knows this criticism is nonsense. But somebody has to set the written record straight for future historians,
so I will do it as part of this celebration. Fortunately this particular issue is so easily settled that this can be a very
short paper. Since Asher is a master of the very short paper, my Peresian brevity is an important part of my act of homage. The criticism I address can be found in a new
formulation by Karl Hess and Walter Philipp(1) of their view that all versions of Bell’s theorem are fundamentally flawed.
I focus here only on their criticism of the version in Asher’s book.(2)
This essay was completed and submitted before the sad and unexpected death of Asher Peres on January 1, 2005. I have left
it in its original form because I sent Asher a preprint, and he told me that his wife Aviva had enjoyed it. I like to think
that perhaps he had a quick look and enjoyed it a bit himself. Life in the field of quantum foundations will not be as much
fun without his opinions, his wit, and his warmth I point out that in spite of recent claims to the contrary, the proof of
Bell’s theorem in Asher Peres’s book works even in the presence of time-correlated hidden variables in the detectors. 相似文献
8.
Murray Peshkin 《Foundations of Physics》2006,36(1):19-29
The key assumption is that of Leinaas and Myrheim and of Berry and Robbins, here specialized to spin zero: for n particles, the argument of the wave function should be the unordered multiplet {r
1,r
2,...,r
n
}. I also make use of the requirement that wave functions in the domain of the Hamiltonian must be continuous functions of the spatial variables. The new proof presented here has advantages of simplicity and transparency in comparison with earlier work based on the same two principles and it uses weaker assumptions, especially avoiding the use of rotations of the relative coordinate of identical particles.This paper is offered as a respectful memorial to the late Asher Peres, whose work was enormously influential in advancing quantum physics at the foundations level. 相似文献
9.
Pawel Horodecki 《Central European Journal of Physics》2003,1(4):695-707
We consider the problem of invariance of distillable entanglement D and quantum capacities Q under erasure of information about single copy of quantum state or channel respectively. We argue that any 2 ⊗N two-way distillable state is still two-way distillable after erasure of single copy information. For some known distillation
protocols the obtained two-way distillation rate is the same as if Alice and Bob knew the state from the very beginning. The
isomorphism between quantum states and quantum channels is also investigated. In particular it is pointed out that any transmission
rate down the channel is equal to distillation rate with formal LOCC-like superoperator that uses in general nonphysical Alice
actions. This allows to we prove that if given channel Λ has nonzero capacity (Q
→ or Q
⟺) then the corresponding quantum state ϱ(Λ) has nonzero distillable entanglement (D
→ or D
⟺). Follwoing the latter arguments are provided that any channel mapping single qubit into N level system allows for reliable two-way transmission after erasure of information about single copy. Some open problems
are discussed. 相似文献
10.
S. von Rotz M.P. Locher V.E. Markushin 《The European Physical Journal A - Hadrons and Nuclei》2000,7(2):261-269
We evaluate three meson doorway mechanisms for nucleon-antinucleon annihilation at rest for the first time. Detailed results
are presented for the final state φπ0 originating from the 3S1 initial state and for the φρ channel originating from 1S0. The results presented also include the improved contributions from two meson doorway states and from the tree diagrams.
For all the channels considered a consistent explanation of large and small OZI violations emerges.
Received: 22 December 1999 相似文献
11.
Benjamin Fain 《Foundations of Physics Letters》1997,10(3):221-233
The prerequisite of quantum measurement is a transformation of an initially off-diagonal density matrix
ρmα;nβ
describing an interacting measured object and measuring device into a diagonal density matrix
ρmα;mαδmnδαβ
. The latter density matrix describes a proper mixture of states having definitem-values. On the other hand, the irreversible relaxation (towards the thermodynamic equilibrium) is also characterized by transformation
of an initially off-diagonal matrix into a diagonal one. It has been shown that the process of irreversible relaxation can
be used to perform quantum measurement, provided the duration Δt of the measurement is much larger thanT
2, the phase relaxation time, and much smaller thanT
1, the population relaxation time:T
2 ≪ Δt ≪T
1. Agedanken experiment describing this kind of measurement is provided. Aπ/2-pulse transforms an initials
z
= −1/2 state into superposition ofs
z
= ±1/2 states. The irreversible relaxation leads to the proper mixture ofs
z
= 1/2 ands
z
= −1/2 state. Results of the measurements are verified by the second electromagnetic pulse. 相似文献
12.
J. T. Lunardi L. A. Manzoni A. T. Nystrom B. M. Perreault 《Journal of Russian Laser Research》2011,32(5):431-438
We consider the average time for a localized wave packet to tunnel through a finite rectangular barrier, as prescribed by
the Salecker–Wigner–Peres clock after a post-selection of transmitted final states. We investigate the properties of this
time both in the relativistic and nonrelativistic regimes and address the questions of the emergence of the Hartman effect
and superluminal tunneling velocities. 相似文献
13.
D. M. Sedrakyan D. A. Badalyan V. M. Gasparyan A. Zh. Khachatryan 《Journal of Experimental and Theoretical Physics》1997,84(2):317-321
We find the dependence of the ensemble-averaged resistance, 〈ρ
L〉, of a one-dimensional chain consisting of periodically spaced random delta-function potentials of the chain length L, the incident-electron energy, and the chain disorder parameter w. We show that generally the 〈ρ
L〉 vs L dependence can be written as a sum of three exponential functions, two of which tend to zero as L℩∞. Hence the asymptotic expression for 〈ρ
L〉 is always an exponential function of L. Such an expression for 〈ρ
L〉 means that the electronic states are indeed localized and makes it possible (which is important) to find the dependence
of the localization radius on the incident-electron energy and the force with which an electron interacts with the sites of
the chain. We also derive a recurrence representation for 〈ρ
L〉, which proves convenient in numerical calculations.
Zh. éksp. Teor. Fiz. 111, 575–584 (February 1997) 相似文献
14.
Hatem Najar 《Journal of statistical physics》2008,130(4):713-725
In this paper we continue with the investigation of the behavior of the integrated density of states of random operators of
the form H
ω
=−∇
ρ
ω
∇. In the present work we are interested in its behavior at 0, the bottom of the spectrum of H
ω
. We prove that it converges exponentially fast to the integrated density of states of some periodic operator
. Being periodic,
cannot exhibit a Lifshitz behaviour. This result relates to the result of S.M. Kozlov (Russ. Math. Surv. 34(4):168–169, 1979) and improves it.
Research partially supported by the Research Unity 01/UR/ 15-01 projects. 相似文献
15.
It has recently been shown that any physical quantity ℛ, in perturbation theory, can be obtained as a function of only the
renormalization scheme (rs) invariants,ρ
0,ρ
1,ρ
2, … Physical predictions, to any given order, are renormalization scheme independent in this approach. Quantum chromodynamics
(qcd) predictions to second order, within thisrs-invariant perturbation theory, are given here for several processes. These lead to some novel relations between experimentally
measurable quantities, which do not involve the unknownqcd scale parameter Λ. They can therefore be directly confronted with experiments and this has been done wherever possible. It
is suggested that these relations can be used to probe the neglected higher order corrections. 相似文献
16.
The idea of the vector dominance is still in use in various analyses of the experimental data of photon–hadron reactions.
It makes sense, therefore, to recast results of microscopic calculations of such reactions in this language. Here we present
the diffractive DIS ρ3 production as a specific correction to generalized vector dominance. We perform a coupled channel analysis of spin–orbital
excitations in diffractive photoproduction and reiterate the point that ρ3 in diffractive DIS will be sensitive to a novel aspect of diffraction. 相似文献
17.
As quantum information science approaches the goal of constructing quantum computers, understanding loss of information through
decoherence becomes increasingly important. The information about a system that can be obtained from its environment can facilitate
quantum control and error correction. Moreover, observers gain most of their information indirectly, by monitoring (primarily
photon) environments of the “objects of interest.” Exactly how this information is inscribed in the environment is essential
for the emergence of “the classical” from the quantum substrate. In this paper, we examine how many-qubit (or many-spin) environments
can store information about a single system. The information lost to the environment can be stored redundantly, or it can
be encoded in entangled modes of the environment. We go on to show that randomly chosen states of the environment almost always
encode the information so that an observer must capture a majority of the environment to deduce the system’s state. Conversely,
in the states produced by a typical decoherence process, information about a particular observable of the system is stored
redundantly. This selective proliferation of “the fittest information” (known as Quantum Darwinism) plays a key role in choosing
the preferred, effectively classical observables of macroscopic systems. The developing appreciation that the environment
functions not just as a garbage dump, but as a communication channel, is extending our understanding of the environment’s
role in the quantum-classical transition beyond the traditional paradigm of decoherence. 相似文献
18.
F. Ellinghaus W.-D. Nowak A.V. Vinnikov Z. Ye 《The European Physical Journal C - Particles and Fields》2006,46(3):729-739
We investigate the possibility of acquiring information on the generalized parton distribution E and, through a model for
E, also on the u-quark total angular momentum Ju by studying deeply virtual Compton scattering and hard exclusive ρ0 electroproduction on a transversely polarized hydrogen target at HERMES. It is found that a change in Ju from zero to 0.4 corresponds to a 4σ (2σ) difference in the calculated transverse target-spin asymmetry in deeply virtual
Compton scattering (ρ0 electroproduction), where σ is the total experimental uncertainty.
PACS 12.38.Bx, 13.60.Le 相似文献
19.
20.
V. Fayaz H. Hossienkhani F. Felegary 《International Journal of Theoretical Physics》2012,51(8):2656-2664
We have investigated general Bianchi type I cosmological models which containing a perfect fluid and dark energy with time varying G and Λ that have been presented. The perfect fluid is taken to be one obeying the equation of state parameter, i.e., p=ωρ; whereas the dark energy density is considered to be either modified polytropic or the Chaplygin gas. Cosmological models admitting both power-law which is explored in the presence of perfect fluid and dark energy too. We reconstruct gravitational parameter G, cosmological term Λ, critical density ρ c , density parameter Ω, cosmological constant density parameter Ω Λ and deceleration parameter q for different equation of state. The present study will examine non-linear EOS with a general nonlinear term in the energy density. 相似文献