3,589 research outputs found

    Model dependence of the bremsstrahlung effects from the superluminal neutrino at OPERA

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    We revisit the bremsstrahlung process of a superluminal neutrino motivated by OPERA results. From a careful analysis of the plane wave solutions of the superluminal neutrino, we find that the squared matrix elements contain additional terms from Lorentz violation due to the modified spin sum for the neutrino. We point out that the coefficients of the decay rate and the energy loss rate significantly depend on the details of the model, although the results are parametrically similar to the ones obtained by Cohen and Glashow [1]. We illustrate this from the modified neutral current interaction of neutrino with Lorentz violation of the same order as in the modified dispersion relation.Comment: 10 pages, no figures, version to appear as a Rapid Communication in Phys. Rev.

    On the robustness of the primordial power spectrum in renormalized Higgs inflation

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    We study the cosmological consequences of higher-dimensional operators respecting the asymptotic symmetries of the tree-level Higgs inflation action. The main contribution of these operators to the renormalization group enhanced potential is localized in a compact field range, whose upper limit is close to the end of inflation. The spectrum of primordial fluctuations in the so-called universal regime turns out to be almost insensitive to radiative corrections and in excellent agreement with the present cosmological data. However, higher-dimensional operators can play an important role in critical Higgs inflation scenarios containing a quasi-inflection point along the inflationary trajectory. The interplay of radiative corrections with this quasi-inflection point may translate into a sizable modification of the inflationary observables.Comment: 12 pages, 8 figures - matches the published versio

    The Planck and LHC results and particle physics

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    I will discuss the recent LHC and Planck results, which are completely compatible with the Standard Model of particle physics, and the standard cosmological model (Λ\LambdaCDM), respectively. It turns out that the extension of the Standard Model is, of course, required, but can be very minimal. I will discuss also what future measurements may be important to test this approach.Comment: 7 pages, talk on the EPS-HEP 2013 prepared for conference proceeding

    Dynamics of Unitarization by Classicalization

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    We study dynamics of the classicalization phenomenon suggested in arXiv:1010.1415, according to which a class of non-renormalizable theories self-unitarizes at high-energies via creation of classical configurations (classicalons). We study this phenomenon in an explicit model of derivatively-self-coupled scalar that serves as a prototype for a Nambu-Goldstone-St\"uckelberg field. We prepare the initial state in form of a collapsing wave-packet of a small occupation number but of very high energy, and observe that the classical configuration indeed develops. Our results confirm the previous estimates, showing that because of self-sourcing the wave-packet forms a classicalon configuration with radius that increases with center of mass energy. Thanks to self-sourcing by energy, unlike solitons, the production of classicalons dominates the high-energy scattering. In order to confront classicalizing and non-classicalizing theories, we use a language in which the scattering cross section can be universally understood as a geometric cross section set by a classical radius down to which waves can propagate freely. The difference is, that in non-classicalizing examples this radius shrinks with increasing energy, whereas in classicalizing theories expands and becomes macroscopic. We study analogous scattering in a Galileon system and discover that classicalization is less efficient there. We thus observe, that classicalization is source-sensitive and that Goldstones pass the first test.Comment: 20 page
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