The Lambda-cold-dark-matter (LCDM) model has established itself as a fantastic (yet parametric) concordance model able to adjust a wide variety of cosmological observables — CMB, BBN, Large Scale Structure (LSS) […]
I will discuss string theory compactifications where a large number of moduli is stabilized by fluxes. I will first present a conjecture which rules out the stabilization of all complex-structure moduli […]
This is a meeting on topics related to string and field theory, between members of nearby institutions: IP2I (CNRS, UCBL), Lyon LAPTh (CNRS, USMB), Annecy LPENSL (CNRS, ENSL), Lyon More […]
We discuss flux compactifications of Type IIA supergravity on G2 spaces with smeared O2/O6-planes down to three dimensions. We start by presenting the setup of allowed fluxes, the internal geometry, […]
Abstract: https://arxiv.org/abs/2203.13276 https://iopscience.iop.org/article/10.3847/2041-8213/ab3e0a (1904.01765)
Modulations of X-ray spectra from extragalactic sources might provide a signature of photons converting into axion-like particles (ALPs) when traversing a region with a large-scale magnetic field. A crucial unknown […]
In 1976, S. Weinberg and his student, E. Gildener (GW), proposed multi-Higgs models of electroweak symmetry breaking which are clas- sically scale-invariant. If this scale invariance is spontaneously broken, the […]
Cosmological first-order phase transition are said strongly supercooled when the nucleation temperature is much smaller than the critical temperature. They are typical of potentials which feature nearly scale-invariance, for which the bounce action decreases only logarithmically with time. The phase transition takes place slowly and the probability distribution of bubble nucleation time is maximally spread. […]
Abstract: The ratios $R(D^{(*)})$ are defined as the $tau/mu$ ratio of the branching fractions of exclusive semileptonic $B to D^{(*)}$ decays. They are a powerful test of Lepton Flavour Universality, one of the pillars of the SM, and are determined by the hadronic Form Factors (FFs) describing the $B to D^{(*)}$ decays. Through the novel Dispersive Matrix (DM) approach, […]
The goal of identifying the Standard Model of particle physics and its extensions within string theory has been one of the principal driving forces in string phenomenology. Recently, the incorporation […]
Abstract: For this journal club meeting I will comment on a recent paper by Albert and Rastelli (https://arxiv.org/abs/2203.11950) in which they apply modern S-matrix bootstrap techniques to the old problem […]
