45 research outputs found
Expanding Universe and Dynamical Compactification Using Yang-Mills Instantons
We consider an eight-dimensional Einstein-Yang-Mills theory to explore
whether Yang-Mills instantons formed in extra dimensions can induce the
dynamical instability of our four-dimensional spacetime. We show that the
Yang-Mills instantons in extra dimensions can trigger the expansion of our
universe in four-dimensional spacetime as well as the dynamical
compactification of extra dimensions. We also discuss a possibility to realize
a reheating mechanism via the quantum back-reaction from the contracting tiny
internal space with a smeared instanton.Comment: v3; 26 pages, 6 figures, version to be published in JHE
Configuration entropy and instability of accelerating black hole in AdS
We consider the accelerating black hole with the negative cosmological
constant in four-dimensional spacetime. There are two configurations such as
the black string (BS) phase when the mass parameter is zero and the black hole
(BH) phase when the mass parameter is non-zero. We investigate their stability
via the configuration entropy (CE). It is found that the BS is not always
stable but the BH has a thermally stable range below the critical mass of the
BH, which is consistent with thermodynamic instability.Comment: 7 pages, 7 figure