3,243 research outputs found
A Note On Clauser-Horne-Shimony-Holt Inequality
Clauser-Horne-Shimony-Holt inequality, an extension of Bell\u27s inequality, is of great importance to modern quantum computation and quantum cryptography. So far, all experimental demonstrations of entanglement are designed to check Bell\u27s inequality or Clauser-Horne-Shimony-Holt inequality. In this note, we specify the math assumptions needed in the argument for Clauser-Horne-Shimony-Holt inequality. We then show the math argument for this inequality is totally indispensable of any physical interpretation, including the hidden variable interperation for EPR thought experiment and the Copenhagen interpretation for quantum mechanics
Philosophy Enters the Optics Laboratory: Bell's Theorem and its First Experimental Tests (1965-1982)
This paper deals with the ways that the issue of completing quantum mechanics
was brought into laboratories and became a topic in mainstream quantum optics.
It focuses on the period between 1965, when Bell published what now we call
Bell's theorem, and 1982, when Aspect published the results of his experiments.
I argue that what was considered good physics after Aspect's experiments was
once considered by many a philosophical matter instead of a scientific one, and
that the path from philosophy to physics required a change in the physics
community's attitude about the status of the foundations of quantum mechanics.Comment: 57 pages, accepted by Studies in History and Philosophy of Modern
Physic
Shifting the Quantum-Classical Boundary: Theory and Experiment for Statistically Classical Optical Fields
The growing recognition that entanglement is not exclusively a quantum
property, and does not even originate with Schr\"odinger's famous remark about
it [Proc. Camb. Phil. Soc. 31, 555 (1935)], prompts examination of its role in
marking the quantum-classical boundary. We have done this by subjecting
correlations of classical optical fields to new Bell-analysis experiments, and
report here values of the Bell parameter greater than . This
is many standard deviations outside the limit established by the
Clauser-Horne-Shimony-Holt (CHSH) Bell inequality [Phys. Rev. Lett. 23, 880
(1969)], in agreement with our theoretical classical prediction, and not far
from the Tsirelson limit . These results cast a new light
on the standard quantum-classical boundary description, and suggest a
reinterpretation of it.Comment: Comments and Remarks are warmly welcome! arXiv admin note: text
overlap with arXiv:1406.333
Does Clauser-Horne-Shimony-Holt Correlation or Freedman-Clauser Correlation lead to the largest violation of Bell's Inequality?
An inequality is deduced from Einstein's locality and a supplementary
assumption. This inequality defines an experiment which can actually be
performed with present technology to test local realism. Quantum mechanics
violate this inequality a factor of 1.5. In contrast, quantum mechanics
violates previous inequalities (for example, Clauser-Horne-Shimony-Holt
inequality of 1969, Freedman-Clauser inequality of 1972, Clauser-Horne
inequality of 1974) by a factor of . Thus the magnitude of violation
of the inequality derived in this paper is approximately larger than
the magnitude of violation of previous inequalities. This result can be
particularly important for the experimental test of locality.Comment: 15 pages, LaTeX file, no figure
An experimental test of non-local realism
Most working scientists hold fast to the concept of 'realism' - a viewpoint
according to which an external reality exists independent of observation. But
quantum physics has shattered some of our cornerstone beliefs. According to
Bell's theorem, any theory that is based on the joint assumption of realism and
locality (meaning that local events cannot be affected by actions in space-like
separated regions) is at variance with certain quantum predictions. Experiments
with entangled pairs of particles have amply confirmed these quantum
predictions, thus rendering local realistic theories untenable. Maintaining
realism as a fundamental concept would therefore necessitate the introduction
of 'spooky' actions that defy locality. Here we show by both theory and
experiment that a broad and rather reasonable class of such non-local realistic
theories is incompatible with experimentally observable quantum correlations.
In the experiment, we measure previously untested correlations between two
entangled photons, and show that these correlations violate an inequality
proposed by Leggett for non-local realistic theories. Our result suggests that
giving up the concept of locality is not sufficient to be consistent with
quantum experiments, unless certain intuitive features of realism are
abandoned.Comment: Minor corrections to the manuscript, the final inequality and all its
conclusions do not change; description of corrections (Corrigendum) added as
new Appendix III; Appendix II replaced by a shorter derivatio
On the equivalence of Clauser-Horne and Eberhard inequality based tests
Recently, the results of the first experimental test for entangled photons
closing the detection loophole (also referred to as the fair sampling loophole)
were published (Vienna, 2013). From the theoretical viewpoint the main
distinguishing feature of this long-aspired experiment was that the Eberhard
inequality was used. Almost simultaneously another experiment closing this
loophole was performed (Urbana-Champaign, 2013) and it was based on the
Clauser-Horne inequality (for probabilities). The aim of this note is to
analyze the mathematical and experimental equivalence of tests based on the
Eberhard inequality and various forms on the Clauser-Horne inequality. The
structure of the mathematical equivalence is nontrivial. In particular, it is
necessary to distinguish between algebraic and statistical equivalence.
Although the tests based on these inequalities are algebraically equivalent,
they need not be equivalent statistically, i.e., theoretically the level of
statistical significance can drop under transition from one test to another (at
least for finite samples). Nevertheless, the data collected in the Vienna-test
implies not only a statistically significant violation of the Eberhard
inequality, but also of the Clauser-Horne inequality (in the ratio-rate form):
for both a violation Comment: a few misprints were correcte
Strong Violations of Bell-type Inequalities for Path-Entangled Number States
We show that nonlocal correlation experiments on the two spatially separated
modes of a maximally path-entangled number state may be performed and lead to a
violation of a Clauser-Horne Bell inequality for any finite photon number N. We
present also an analytical expression for the two-mode Wigner function of a
maximally path-entangled number state and investigate a
Clauser-Horne-Shimony-Holt Bell inequality for such states. We test other
Bell-type inequalities. Some are violated by a constant amount for any N.Comment: 6 pages, LaTex; revised version accepted for publication in PR
- …