4,113 research outputs found
Nonlocal effects in Fock space
If a physical system contains a single particle, and if two distant detectors
test the presence of linear superpositions of one-particle and vacuum states, a
violation of classical locality can occur. It is due to the creation of a
two-particle component by the detecting process itself.Comment: final version in PRL 74 (1995) 4571; 76 (1996) 2205 (erratum
Bell's inequality with Dirac particles
We study Bell's inequality using the Bell states constructed from four
component Dirac spinors. Spin operator is related to the Pauli-Lubanski pseudo
vector which is relativistic invariant operator. By using Lorentz
transformation, in both Bell states and spin operator, we obtain an observer
independent Bell's inequality, so that it is maximally violated as long as it
is violated maximally in the rest frame.Comment: 7 pages. arXiv admin note: text overlap with arXiv:quant-ph/0308156
by other author
Spacings and pair correlations for finite Bernoulli convolutions
We consider finite Bernoulli convolutions with a parameter
supported on a discrete point set, generically of size . These sequences
are uniformly distributed with respect to the infinite Bernoulli convolution
measure , as tends to infinity. Numerical evidence suggests that for
a generic , the distribution of spacings between appropriately rescaled
points is Poissonian. We obtain some partial results in this direction; for
instance, we show that, on average, the pair correlations do not exhibit
attraction or repulsion in the limit. On the other hand, for certain algebraic
the behavior is totally different.Comment: 17 pages, 6 figure
Note on Invariants of the Weyl Tensor
Algebraically special gravitational fields are described using algebraic and
differential invariants of the Weyl tensor. A type III invariant is also given
and calculated for Robinson-Trautman spaces.Comment: 3 pages, no figures, corrected expression (12
Inductive Entanglement Classification of Four Qubits under SLOCC
Using an inductive approach to classify multipartite entangled states under
stochastic local operations and classical communication introduced recently by
the authors [Phys. Rev. A 74, 052336 (2006)], we give the complete
classification of four-qubit entangled pure states. Apart from the expected
degenerate classes, we show that there exist eight inequivalent ways to
entangle four qubits. In this respect, permutation symmetry is taken into
account and states with a structure differing only by parameters inside a
continuous set are considered to belong to the same class.Comment: 11 pages and no figures. Accepted in PR
A geometric proof of the Kochen-Specker no-go theorem
We give a short geometric proof of the Kochen-Specker no-go theorem for
non-contextual hidden variables models. Note added to this version: I
understand from Jan-Aake Larsson that the construction we give here actually
contains the original Kochen-Specker construction as well as many others (Bell,
Conway and Kochen, Schuette, perhaps also Peres).Comment: This paper appeared some years ago, before the author was aware of
quant-ph. It is relevant to recent developments concerning Kochen-Specker
theorem
Hardy's argument and successive spin-s measurements
We consider a hidden-variable theoretic description of successive
measurements of non commuting spin observables on a input spin-s state. In this
scenario, the hidden-variable theory leads to a Hardy-type argument that
quantum predictions violate it. We show that the maximum probability of success
of Hardy's argument in quantum theory is , which is more
than in the spatial case.Comment: 7 page
- …