118294407
Illuminating WISPs with Photons
Physics beyond the Standard Model naturally gives rise to very light and weakly interacting particles, dubbed WISPs (Weakly Interacting Slim Particles). A prime example is the axion, that has eluded experimental detection for more than thirty years. In this talk we will review some of the strongly motivated candidates for such particles, the observational hints for them and the present status of searches with photon regeneration experiments, as well as possible future improvements.
73721705
Cold Dark Matter from the Hidden Sector
Weakly interacting slim particles (WISPs) such as hidden photons (HP) and axion-like particles (ALPs) have been proposed as cold dark matter candidates. They might be produced non-thermally via the misalignment mechanism, similarly to cold axions. In this talk we review the main processes of thermalisation of HP and we compute the parameter space that may survive as cold dark matter population until today. Our findings are quite encouraging for experimental searches in the laboratory in the near future.
119279933
NEUTRINO OSCILLATIONS IN A MINIMAL CPT VIOLATION FRAME
The oscillation neutrino problem in the extended standard model with minimal number of parameters is considered. The dispersion relations with explicit neutrino–antineutrino asymmetry are discussed and an explanation to the MINIBooNE and solar neutrino controversy is offered. Bounds for the CPT violation symmetry are also found.
117024657
Electrodynamics with an Infrared Scale and PVLAS experiment
We consider an infrared Lorentz violation in connection with recent results of PVLAS experiment. Our analysis is based in a relation that can be established, under certain conditions, between an axial-like-particle theory and electrodynamics with an infrared scale. In the PVLAS case, the conditions imply two dispersion relations such that the infrared scale $|\vec \theta|$, the inverse axion-photon coupling constant $M^{-1}$ and the external magnetic field ${\vec B}$ can be connected through the formula $|{\vec \theta}|= {|\vec B|}/M$. Our analysis, which only requires a non-dynamical (auxiliar) axial-like field leads to $|{\vec\theta}| \leq 5.4 \times 10^{-7}$ meV and $M^{-1} \sim 1.2 \times 10^{-3}$ GeV $^{-1}$.
119351968
CPT/Lorentz Invariance Violation and Quantum Field Theory
Departamento de Fisica, Universidad de Santiago de ChileCasilla 307, Santiago 2, ChileE-mail: fmendez@lauca.usach.clAnalogies between the noncommutative harmonic oscillator and noncommutative ﬁelds are ana-lyzed. Following this analogywe construct examples of quantum ﬁelds theories with explicit CPTand Lorentz symmetry breaking. Some applications to baryogenesis and neutrino oscillation arealso discussed.Fifth International Conference on Mathematical Methods in Physics — IC2006April 24-28 2006Centro Brasilerio de Pesquisas Fisicas, Rio de Janeiro, Brazil
119184475
Effects of heavy bosonic excitations on QED vacuum
We discuss the contribution of axion-like excitations (ALE) to the vacuum birefringence in the limit mA ≳ ω, where mA is the mass of the excitation and ω the energy of test photons interacting with an external (intense) magnetic field. The relevance of this term with respect to the QED contribution depends on the ratio gA/mA and, from present bounds on the mass and the coupling constant gA, we find that in the present low energy regime, it ranges from 10-14 to 102 suggesting an interesting alternative to explore.
10548982
A Geometric approach to massive p form duality
Massive theories of abelian p-forms are quantized in a generalized path-representation that leads to a description of the phase space in terms of a pair of dual non-local operators analogous to the Wilson Loop and the 't Hooft disorder operators. Special atention is devoted to the study of the duality between the Topologically Massive and the Self-Dual models in 2+1 dimensions. It is shown that these models share a geometric representation in which just one non local operator suffices to describe the observables.
118459607
Quantization of Interacting Non-Relativistic Open Strings using Extended Objects
Non-relativistic charged open strings coupled with Abelian gauge fields are quantized in a geometric representation that generalizes the Loop Representation. The model comprises open-strings interacting through a Kalb-Ramond field in four dimensions. It is shown that a consistent geometric-representation can be built using a scheme of ``surfaces and lines of Faraday'', provided that the coupling constant (the ``charge'' of the string) is quantized.
120081041
AN INTERACTING GAUGE THEORY OF CHARGED PARTICLES AND STRINGS
Using a standard procedure we obtain from the pure gauge theory of Nambu for 3-forms, two interaction theories between three antisymmetric gauge fields of different ranks. These theories are non-equivalent and describe the same dynamical system at the classical level. They could be interpreted as describing the interaction between charged and closed strings.
126306149
QUANTUM ABELIAN SURFACES
118605658
Geometric Representation of Interacting Non-Relativistic Open Strings using Extended Objects
Non-relativistic charged open strings coupled with Abelian gauge fields are quantized in a geometric representation that generalizes the Loop Representation. The model consists of open-strings interacting through a Kalb-Ramond field in four dimensions. The geometric representation proposed uses lines and surfaces that can be interpreted as an extension of the picture of Faraday's lines of classical electromagnetism. This representation results to be consistent, provided the coupling constant (the "charge" of the string) is quantized. The Schr\"odinger equation in this representation is also presented.