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Sergey Sibiryakov

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Publications associées (38)

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Cosmological constraints on deviations from Lorentz invariance in gravity and dark matter

Julien Lesgourgues, Sergey Sibiryakov, Diego Blas Temino, Mikhail Ivanov, Benjamin Audren

We consider a scenario where local Lorentz invariance is violated by the existence of a preferred time direction at every space-time point. This scenario can arise in the context of quantum gravity and its description at low energies contains a unit time-l ...

Iop Publishing Ltd2015

Completing Lorentz violating massive gravity at high energies

Sergey Sibiryakov, Diego Blas Temino

Theories with massive gravitons are interesting for a variety of physical applications, ranging from cosmological phenomena to holographic modeling of condensed matter systems. To date, they have been formulated as effective field theories with a cutoff pr ...

Springer Verlag2015

On stability of electroweak vacuum during inflation

Sergey Sibiryakov, Andrey Shkerin

We study Coleman-De Luccia tunneling of the Standard Model Higgs field during inflation in the case when the electroweak vacuum is metastable. We verify that the tunneling rate is exponentially suppressed. The main contribution to the suppression is the sa ...

Elsevier2015

On holography for (pseudo-)conformal cosmology

Sergey Sibiryakov

We propose a holographic dual for (pseudo-)conformal cosmological scenario, with a scalar field that forms a moving domain wall in adS(5). The domain wall separates two vacua with unequal energy densities. Unlike in the existing construction, the 5d soluti ...

Elsevier2015

Experimental assessment of the speed of light perturbation in free-fall absolute gravimeters

Sergey Sibiryakov, Diego Blas Temino

Precision absolute gravity measurements are growing in importance, especially in the context of the new definition of the kilogram. For the case of free fall absolute gravimeters with a Michelson-type interferometer tracking the position of a free falling ...

Iop Publishing Ltd2015

Semiclassical S-matrix for black holes

Sergey Sibiryakov

We propose a semiclassical method to calculate S-matrix elements for two-stage gravitational transitions involving matter collapse into a black hole and evaporation of the latter. The method consistently incorporates back-reaction of the collapsing and emi ...

Springer2015

From Scale Invariance to Lorentz Symmetry

Sergey Sibiryakov

It is shown that a unitary translationally invariant field theory in 1 + 1 dimensions, satisfying isotropic scale invariance, standard assumptions about the spectrum of states and operators, and the requirement that signals propagate with finite velocity, ...

Amer Physical Soc2014

Prospective constraints on Lorentz violation from ultrahigh-energy photon detection

Sergey Sibiryakov

We point out that violation of Lorentz invariance affects the interaction of high-energy photons with the Earth's atmosphere and magnetic field. In a certain parameter region this interaction becomes suppressed and the photons escape observation, passing t ...

Amer Physical Soc2014

UV-extending ghost inflation

Sergey Sibiryakov, Mikhail Ivanov

We present a setup that provides a partial UV-completion of the ghost inflation model up to a scale which can be almost as high as the Planck mass. This is achieved by coupling the inflaton to the Lorentz-violating sector described by the Einstein-aether t ...

Iop Publishing Ltd2014

Cosmological constraints on Lorentz violating dark energy

Julien Lesgourgues, Sergey Sibiryakov, Diego Blas Temino, Benjamin Audren

The role of Lorentz invariance as a fundamental symmetry of nature has been lately reconsidered in different approaches to quantum gravity. It is thus natural to study whether other puzzles of physics may be solved within these proposals. This may be the c ...

Iop Publishing Ltd2013