Zobrazeno 1 - 10
of 176
pro vyhledávání: '"Tsimpis, Dimitrios"'
We explore the possibility that our universe's current accelerated expansion is explained by a quintessence model with an exponential scalar potential, $V =V_0\, e^{-\lambda\, \phi}$, keeping an eye towards $\lambda \geq \sqrt{2}$ and an open univers
Externí odkaz:
http://arxiv.org/abs/2405.09323
Recently, many works have tried to realize cosmological accelerated expansion in string theory models in the asymptotic regions of field space, with a typical scalar potential $V(\varphi)$ having an exponential fall-off $e^{-\gamma\, \varphi}$. Those
Externí odkaz:
http://arxiv.org/abs/2309.03938
Publikováno v:
Eur. Phys. J. C 83, 325 (2023)
We investigate whether quasinormal modes (QNMs) can be used in the search for signatures of extra dimensions. To address a gap in the Beyond the Standard Model (BSM) literature, we focus here on higher dimensions characterised by negative Ricci curva
Externí odkaz:
http://arxiv.org/abs/2211.08489
Autor:
Marconnet, Paul, Tsimpis, Dimitrios
We study 4d Friedmann-Lema\^{i}tre-Robertson-Walker cosmologies obtained from time-dependent compactifications of Type IIA 10d supergravity on various classes of 6d manifolds (Calabi-Yau, Einstein, Einstein-K\"{a}hler). The cosmologies we present are
Externí odkaz:
http://arxiv.org/abs/2210.10813
We obtain the spectrum of the Dirac operator on the three-dimensional Heisenberg nilmanifold $\mathcal{M}_3$, and its complete dependence on the metric moduli. As an application, we construct the four-dimensional low-energy effective action obtained
Externí odkaz:
http://arxiv.org/abs/2202.11437
Autor:
Tsimpis, Dimitrios
In orbifold vacua containing an $S^q/\Gamma$ factor, we compute the relative order of scale separation, $r$, defined as the ratio of the eigenvalue of the lowest-lying $\Gamma$-invariant state of the scalar Laplacian on $S^q$, to the eigenvalue of th
Externí odkaz:
http://arxiv.org/abs/2201.10916
We consider the compactification of a Yang-Mills theory on a three-dimensional nilmanifold. The compactification generates a Yang-Mills theory in four space-time dimensions, coupled to a specific scalar sector. The compactification geometry gives ris
Externí odkaz:
http://arxiv.org/abs/2201.01151
A distinct signature of compact extra dimensions would be a Kaluza-Klein tower of gravitational waves. Motivated by this prospect, we compute the corresponding spectrum on a warped toroidal background. We evaluate in particular the impact of the warp
Externí odkaz:
http://arxiv.org/abs/2103.09240
Autor:
Lust, Dieter, Tsimpis, Dimitrios
In this note we examine certain classes of solutions of IIA theory without sources, of the form AdS$_2\times {\cal M}^{(1)}\times \dots \times {\cal M}^{(n)}$, where ${\cal M}^{(i)}$ are Riemannian spaces. We show that large hierarchies of curvatures
Externí odkaz:
http://arxiv.org/abs/2004.07582
We present a method to obtain a scalar potential at tree level from a pure gauge theory on nilmanifolds, a class of negatively-curved compact spaces, and discuss the spontaneous symmetry breaking mechanism induced in the residual Minkowski space afte
Externí odkaz:
http://arxiv.org/abs/2002.11128