Lucila Kraiselburd

Constraining the fundamental interactions and couplings with Eötvös experiments

Abstract Upper bounds for the violation of the Weak Equivalence Principle (WEP) by the fundamental interactions have been given before. We now recompute the limits on the parameters measuring the strength of the violation with the whole set of high accuracy Eotvos experiments. Besides, limits on spatial variation of the fundamental constants α , sin 2 θ W and v , the vacuum expectation value of the Higgs field, are found in a model independent way. Limits on other parameters in the gauge sector are also found from the structure of the Standard Model.

Variation of the fine-structure constant: an update of statistical analyses with recent data

Aims. We analyze the consistency of different astronomical data of the variation in the fine-structure constant obtained with KECK and VLT. Methods. We tested the consistency using the Student test and confidence intervals. We splited the data sets in to smaller intervals and grouped them acording to redshift and angular position. Another statistical analysis is proposed that considers phenomenological models for the variation in �.

Beyond Bekenstein’s Theory

There are several very different motivations for studying the variation of fundamental constants. They may provide a connection between cosmology and particle physics due to the coincidence of large dimensionless numbers arising from the combination of different physical constants. Bekenstein’s variable charge model is very attractive because it is based on very general assumptions: covariance, gauge invariance, causality and time-reversal invariance of electromagnetism. The generality of its assumptions guarantee the applicability of the scheme to other gauge interactions such as the strong forces. Besides, it introduces a useful simplifying assumption; namely, that the gravitational sector is unaffected by the scalar field introduced to vary the coupling constant. That is why it is interesting to explore first this simplified model, before a similar exploration of more general theories.

The breaking of the Equivalence Principle in theories with varying α

The Standard Model and General Relativity provide a good description of phenomena at low energy. These theories, which agree very well with the experiment, contain a set of parameters called “fundamental constants”, that are assumed invariant under changes in location and reference system. However, their possible variation has been studied since Dirac made the large numbers hypothesis (LNH). Moreover, unified field theory and extra dimensions theories such as Kaluza-Klein or Superstring theories, state not only the variation of these constants, but also the simultaneity of the variations. The Eotvos effect is one of the most sensitive indicators of changes in fundamental constants. Bekenstein (2002) showed that in his theory, using a classical static particle model of matter, there is no Eotvos effect and therefore met the Universality of Free Fall and the Principle of Equivalence. We present different results than those obtained by Bekenstein, Kraiselburd, Vucetich (2009). Modifying his theory, taking more realistic models of matter and using the model TH μ techniques (Ligtman-Lee (1975) and Haugan (1979), not used before to analyze this model), very small but measurable effects have been found.