642 research outputs found
How to test SME with space missions ?
In this communication, we focus on possibilities to constrain SME
coefficients using Cassini and Messenger data. We present simulations of
radioscience observables within the framework of the SME, identify the linear
combinations of SME coefficients the observations depend on and determine the
sensitivity of these measurements to the SME coefficients. We show that these
datasets are very powerful for constraining SME coefficients.Comment: Presented at the Sixth Meeting on CPT and Lorentz Symmetry,
Bloomington, Indiana, June 17-21, 2013. 4 pages, 1 figur
Large scale EPR correlations and cosmic gravitational waves
We study how quantum correlations survive at large scales in spite of their
exposition to stochastic backgrounds of gravitational waves. We consider
Einstein-Podolski-Rosen (EPR) correlations built up on the polarizations of
photon pairs and evaluate how they are affected by the cosmic gravitational
wave background (CGWB). We evaluate the quantum decoherence of the EPR
correlations in terms of a reduction of the violation of the Bell inequality as
written by Clauser, Horne, Shimony and Holt (CHSH). We show that this
decoherence remains small and that EPR correlations can in principle survive up
to the largest cosmic scales.Comment: 5 figure
New physicochemical interpretations for Adsorption of Trichloroethylene on Activated Carbon: Steric and Energetic Interpretation using Statistical Physics Approach
Experimental adsorption isotherms of trichloroethylene (TCE) on activated carbon at four temperatures were analyzed theoretically by a double layer with one energy established through statistical physics approach. This model contains three parameters affecting the adsorption process i.e. the number of molecules per site n, the monolayer adsorbed quantity Q0 and the concentration at half- saturation c1/2. In this work, we propose a steric and energetic interpretation for the different adsorption isotherms of TCE on activated carbon. We calculate also the thermodynamic functions to characterize the adsorption process such as, entropy, free energy, and internal energy as function concentration. The different parameters and the thermodynamic functions were discussed with temperature
Agroecology: Polysemy, Pluralism And Controversies
In recent years, a growing number of actors and institutions, in different countries, have begun using the notion of Agroecology, which has led to an expansion of its polysemy and its controversies. Taking this into account, this paper analyzes, based on the Brazilian and French experiences, the peculiarities of Agroecology in four different fields: science, social movements, government policies, and education. It also discusses three other issues: the analytical, programmatic and normative discourses; the different definitions, in the fields of science and education, of the object of study of Agroecology; and the different formulations regarding its fundamental principles. It is argued that, in this new context, recognition of this pluralism and the controversies acquires a central role in the construction of knowledge in the various fields linked to Agroecology.19312
Testing Gravitation in the Solar System with Radio Science experiments
The laws of gravitation have been tested for a long time with steadily
improving precision, leading at some moment of time to paradigmatic evolutions.
Pursuing this continual effort is of great importance for science. In this
communication, we focus on Solar System tests of gravity and more precisely on
possible tests that can be performed with radio science observations (Range and
Doppler). After briefly reviewing the current tests of gravitation at Solar
System scales, we give motivations to continue such experiments. In order to
obtain signature and estimate the amplitude of anomalous signals that could
show up in radio science observables because of modified gravitational laws, we
developed a new software that simulates Range/Doppler signals. We present this
new tool that simulates radio science observables directly from the space-time
metric. We apply this tool to the Cassini mission during its cruise from
Jupiter to Saturn and derive constraints on the parameters entering alternative
theories of gravity beyond the standard Parametrized Post Newtonian theory.Comment: proceedings of SF2A 2011 - minor changes (typos corrected -
references updated
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