Speaker
Dr
Sergey Sibiryakov
(INR RAS)
Description
We present a model of dark energy where the parameter setting the rate of cosmic
acceleration has technically natural value, i.e. it does not receive corrections from other scales in the theory. The proposed acceleration mechanism appears generically in the low-energy limit of gravity with violation of Lorentz invariance and spontaneously broken internal global symmetries. The model is a valid effective field theory up to a high cutoff just a few orders of magnitude below the Planck scale. Furthermore, it can be UV completed in the context of Horava gravity. We discuss the observational predictions of the model. While the expansion history of the Universe turns out to be essentially indistinguishable from that of LCDM, the matter power spectrum is enhanced at subhorizon scales. The latter property can be used to discriminate the model from LCDM with current cosmological data.
Author
Dr
Sergey Sibiryakov
(INR RAS)
Co-author
Dr
Diego Blas
(EPFL)
