28,361 research outputs found
On the spectral shift and the time delay of light in a Rindler accelerated frame
We discuss two effects predicted by the general theory of relativity in the
context of Rindler accelerated observers: the gravitational spectral shift and
the time delay of light. We show that these effects also appear in a Rindler
frame in the absence of gravitational field, in accordance with the Einstein's
equivalence principle.Comment: 12 pages, 3 figure
Memory effect in triglycine sulfate induced by a transverse electric field: specific heat measurement
The influence of a transverse electric field in the specific heat of
triglycine sulphate (TGS) has been studied. The specific heat of TGS has been
measured heating the sample from ferroelectric to paraelectric phase after
prolonged transverse electric field (i.e. perpendicular to the ferroelectric
axis). It is shown that the specific heat of TGS can remember the temperature
at which the transverse field was previously applied.Comment: ReVTeX4 Twocolumn 4 pages, 4 figure
Simple quantum model for light depolarization
Depolarization of quantum fields is handled through a master equation of the
Lindblad type. The specific feature of the proposed model is that it couples
dispersively the field modes to a randomly distributed atomic reservoir, much
in the classical spirit of dealing with this problem. The depolarizing dynamics
resulting from this model is analyzed for relevant states.Comment: Improved version. Accepted for publication in the Journal of the
Optical Society of America
LeMoMaF: Lensed Mock Map Facility
We present the Lensed Mock Map Facility (LeMoMaF), a tool designed to perform
mock weak lensing measurements on numerically simulated chunks of the universe.
Coupling N-body simulations to a semi-analytical model of galaxy formation,
LeMoMaF can create realistic lensed images and mock catalogues of galaxies, at
wavelengths ranging from the UV to the submm. To demonstrate the power of such
a tool we compute predictions of the source-lens clustering effect on the
convergence statistics, and quantify the impact of weak lensing on galaxy
counts in two different filters. We find that the source-lens clustering effect
skews the probability density function of the convergence towards low values,
with an intensity which strongly depends on the redshift distribution of
galaxies. On the other hand, the degree of enhancement or depletion in galaxy
counts due to weak lensing is independent of the source-lens clustering effect.
We discuss the impact on the two-points shear statistics to be measured by
future missions like SNAP and LSST. The source-lens clustering effect would
bias the estimation of sigma_8 from two point statistics by 2% -5%. We conclude
that accurate photometric redshifts for individual galaxies are necessary in
order to quantify and isolate the source-lens clustering effect.Comment: 14 pages, 11 figures, submitted to MNRA
Violation of Leggett inequalities in orbital angular momentum subspaces
We report an experimental test of Leggett's non-local hidden variable theory in an orbital angular momentum (OAM) state space of light. We show that the correlations we observe are in conflict with Leggett's model, thus excluding a particular class of non-local hidden variable theories for the first time in a non-polarization state space. It is known that the violation of the Leggett inequality becomes stronger as more detection settings are used. The required measurements become feasible in an OAM subspace, and we demonstrate this by testing the inequality using three and four settings. We observe excellent agreement with quantum predictions and a violation of five and six standard deviations, respectively, compared to Leggett's non-local hidden variable theory
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