Related papers: Kaluza-Klein relics from warped reheating
We investigate the scalar metric perturbations about a de Sitter brane universe in a 5-dimensional anti de Sitter bulk. We compare the master-variable formalism, describing metric perturbations in a 5-dimensional longitudinal gauge, with…
In the early Universe, as a consequence of $U(1)_{B-L}$ gauge symmetry-breaking, the so-called $B-L$ cosmic strings are expected to be produced at the breaking scale $\eta_{B-L}$ according to the Kibble mechanism. The decaying, collapsing…
We discuss the effects from the Kaluza-Klein modes in the brane world scenario when an interaction between bulk and brane fields is included. We focus on the bulk inflaton model, where a bulk field $\Psi$ drives inflation in an almost…
We exploit moderately resolved [OIII], [CII] and dust continuum ALMA observations to derive the gas density ($n$), the gas-phase metallicity ($Z$) and the deviation from the Kennicutt-Schmidt (KS) relation ($\kappa_s$) on ~sub-kpc scales in…
We use the existing catalog of Damped Lyman-Alpha (DLA) systems to place constraints on the amount of evolution in the baryonic content of galaxies and on the value of the cosmological constant. The density of cold gas at redshifts z=3+-1…
We solve the standard Lifshitz-Slyozov (LS) model with conservation of total particles in the limit of small super-saturation. The new element is an effective initial condition that follows from the initial exhaustion of nucleation as…
We argue that in fat brane-world scenarios the light propagating in vacuum will, because of massive ``Kaluza-Klein'' (KK) excitations, experience a refraction. The motion of a photon inside a fat brane can be decomposed in the longitudinal…
We derive constraints on the tensor to scalar ratio and on the background charge of the warped throat for DBI inflation driven by D5- and D7-branes wrapped over cycles of the throat. It is shown that the background charge well beyond the…
There exists a well known problem with the Li7+Be7 abundance predicted by standard big bang nucleosynthesis being larger than the value observed in population II stars. The catalysis of big bang nucleosynthesis by metastable, \tau_X \ge…
We point out some of the outstanding challenges for embedding inflationary cosmology within string theory studying the process of reheating for models where the inflaton is a closed string mode parameterising the size of an internal cycle…
Fluctuations in the intensity and polarization of the cosmic microwave background (CMB) and the large-scale distribution of matter in the universe each contain clues about the nature of the earliest moments of time. The next generation of…
We study the bounds states of the Kaluza-Klein (KK) excitations of quarks in models of Universal Extra Dimensions. Such bound states may be detected at future lepton colliders in the cross section for the pair-production of KK-quarks near…
We study the spectrum of the gravitational modes in Minkowski spacetime due to a 6-dimensional warped deformed conifold, i.e., a warped throat, in superstring theory. After identifying the zero mode as the usual 4D graviton, we present the…
It was recently shown that in warped compactifications based on a Klebanov-Strassler throat there is a light complex structure field, governing the size of the throat and the redshift at its tip. We show that after uplift of the…
We show that the Kontsevich-Segal (KS) criterion, applied to the complex saddles that specify the semiclassical no-boundary wave function, acts as a selection mechanism on inflationary scalar field potentials. Completing the observable…
We consider the influence of extra dimensions on the force in Casimir pistons. Suitable analytical expressions are provided for the Casimir force in the range where the plate distance is small, and that where it is large, compared to the…
We show that brane inflation is very sensitive to tiny sharp features in extra dimensions, including those in the potential and in the warp factor. This can show up as observational signatures in the power spectrum and/or non-Gaussianities…
In this work, we propose a string-inspired two fields inflation model to address the fine-tuning problem that the standard inflation model suffers. The fast-rolling tachyon $\mathcal{T}$ originated from the D-brane and anti-D-brane pair…
In this paper I will combine and use two Cardy-Jacobsen and Yaffe-Svetitsky conjectures \cite{c.1,c.2} to present a mechanism for a late-time inflation during the electroweak symmetry breaking due to discrete $Z_3$ symmetry at $\textit{O}…
We present constraints on the extended Starobinsky and Weyl gravity model of inflation using updated available observational data. The data includes cosmic microwave background (CMB) anisotropy measurements from Planck and BICEP/Keck 2018…