6,561 research outputs found
On The Relevance Of Fair Sampling Assumption In The Recent Bell Photonic Experiments
In the experimental verification of Bell's inequalities in real photonic
experiments, it is generally believed that the so-called fair sampling
assumption (which means that a small fraction of results provide a fair
statistical sample) has an unavoidable role. Here, we want to show that the
interpretation of these experiments could be feasible, if some different
alternative assumptions other than the fair sampling were used. For this
purpose, we derive an efficient Bell-type inequality which is a CHSH-type
inequality in real experiments. Quantum mechanics violates our proposed
inequality, independent of the detection-efficiency problems.Comment: 13 pages, no figure, one table. Last versio
A very brief introduction to quantum computing and quantum information theory for mathematicians
This is a very brief introduction to quantum computing and quantum
information theory, primarily aimed at geometers. Beyond basic definitions and
examples, I emphasize aspects of interest to geometers, especially connections
with asymptotic representation theory. Proofs of most statements can be found
in standard references
Bell's inequality tests: from photons to B-mesons
We analyse the recent claim that a violation of a Bell's inequality has been
observed in the --meson system [A. Go, {\em Journal of Modern Optics} {\bf
51} (2004) 991]. The results of this experiment are a convincing proof of
quantum entanglement in --meson pairs similar to that shown by polarization
entangled photon pairs. However, we conclude that the tested inequality is not
a genuine Bell's inequality and thus cannot discriminate between quantum
mechanics and local realistic approaches.Comment: 5 page
On A New Formulation of Micro-phenomena: Basic Principles, Stationary Fields And Beyond
In a series of essays, beginning with this article, we are going to develop a
new formulation of micro-phenomena based on the principles of reality and
causality. The new theory provides with us a new depiction of micro-phenomena
assuming an unified concept of information, matter and energy. So, we suppose
that in a definite micro-physical context (including other interacting
particles), each particle is enfolded by a probability field whose existence is
contingent upon the existence of the particle, but it can locally affect the
physical status of the particle in a context-dependent manner. The dynamics of
the whole particle-field system obeys deterministic equations in a manner that
when the particle is subjected to a conservative force, the field also
experiences a conservative complex force which its form is determined by the
dynamics of particle. So, the field is endowed with a given amount of energy,
but its value is contingent upon the physical conditions the particle is
subjected to. Based on the energy balance of the particle and its associated
field, we argue why the field has a probabilistic objective nature. In such a
way, the basic elements of this new formulation, its application for some
stationary states and its nonlinear generalization for conservative systems are
discussed here.Comment: 35 pages, 5 figures, 3 appendice
On the exit statistics theorem of many particle quantum scattering
We review the foundations of the scattering formalism for one particle
potential scattering and discuss the generalization to the simplest case of
many non interacting particles. We point out that the "straight path motion" of
the particles, which is achieved in the scattering regime, is at the heart of
the crossing statistics of surfaces, which should be thought of as detector
surfaces. We sketch a proof of the relevant version of the many particle flux
across surfaces theorem and discuss what needs to be proven for the foundations
of scattering theory in this context.Comment: 15 pages, 4 figures; to appear in the proceedings of the conference
"Multiscale methods in Quantum Mechanics", Accademia dei Lincei, Rome,
December 16-20, 200
Quantum Interferometry, Measurement and Objectivity: Some Basic Features Revisited
The reduction paradigm of quantum interferometry and the objectivation
problem in quantum measurements are reanalyzed. Both are shown to be amenable
to straightforward mathematical treatment within "every-users" simple-minded
quantum mechanics without reduction postulate etc., using only its
probabilistic content.Comment: 5 pages, LaTeX, To be published in Proc. 2nd Interational Symposium
on Fundamental Problems in Quantum Physics, M. Ferrero and A. van der Merve
eds. (Kluwer Academic Publshers, 1997
Mind before matter: reversing the arrow of fundamentality
In this contribution to FQXi's essay contest 2018, I suggest that it is
sometimes a step forward to reverse our intuition on "what is fundamental", a
move that is somewhat reminiscent of the idea of noncommutative geometry. I
argue that some foundational conceptual problems in physics and related fields
motivate us to attempt such a reversal of perspective, and to take seriously
the idea that an information-theoretic notion of observer ("mind") could in
some sense be more fundamental than our intuitive idea of a physical world
("matter"). I sketch what such an approach could look like, and why it would
complement but not contradict the view that the material world is the cause of
our experience.Comment: Contribution to the 2018 FQXi essay contest "What is fundamental?
Quantum correlations from local amplitudes and the resolution of the Einstein-Podolsky-Rosen nonlocality puzzle
The Einstein-Podolsky-Rosen nonlocality puzzle has been recognized as one of
the most important unresolved issues in the foundational aspects of quantum
mechanics. We show that the problem is resolved if the quantum correlations are
calculated directly from local quantities which preserve the phase information
in the quantum system. We assume strict locality for the probability amplitudes
instead of local realism for the outcomes, and calculate an amplitude
correlation function.Then the experimentally observed correlation of outcomes
is calculated from the square of the amplitude correlation function. Locality
of amplitudes implies that the measurement on one particle does not collapse
the companion particle to a definite state. Apart from resolving the EPR
puzzle, this approach shows that the physical interpretation of apparently
`nonlocal' effects like quantum teleportation and entanglement swapping are
different from what is usually assumed. Bell type measurements do not change
distant states. Yet the correlations are correctly reproduced, when measured,
if complex probability amplitudes are treated as the basic local quantities. As
examples we discuss the quantum correlations of two-particle maximally
entangled states and the three-particle GHZ entangled state.Comment: Std. Latex, 11 pages, 1 table. Prepared for presentation at the
International Conference on Quantum Optics, ICQO'2000, Minsk, Belaru
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