We provide a universal microscopic counting for the microstates of asymptotically AdS black holes and strings that arise as solutions half-maximal gauged supergravity in 4 5 dimensions. These can be embedded all M-theory type II string backgrounds with an vacuum 16 supercharges infinite set examples dual to $\mathcal{N}=2$ $\mathcal{N}=4$ conformal field theories four three dimensions, respecti...

Neutron stars are ideal astrophysical sources to probe general relativity due their large compactnesses and strong gravitational fields. For example, binary pulsar wave observations have placed stringent bounds on certain scalar-tensor theories in which a massless scalar field is coupled the metric through matter. A remarkable phenomenon of neutron such spontaneous scalarization, where normaliz...

We discuss cosmology of models with universal extra dimensions, where the Standard Model degrees of freedom live in a 4 + n dimensional brane, with n compact and small extra spatial dimensions. In these models, the simplest way to obtain the conventional 4-dimensional Planck scale starting with a low string scale is to have also some larger extra dimensions, where only gravity propagates. In su...

We show that almost all metric–affine theories of gravity yield Einstein equations with a non–null cosmological constant Λ. Under certain circumstances and for any dimension, it is also possible to incorporate a Weyl vector field Wμ and therefore the presence of an anisotropy. The viability of these field equations is discussed in view of recent astrophysical observations.

We say that a model category is left-determined if the weak equivalences are generated (in a sense specified below) by the cofibrations. While the model category of simplicial sets is not left-determined, we show that its non-oriented variant, the category of symmetric simplicial sets (in the sense of Lawvere and Grandis) carries a natural left-determined model category structure. This is used ...

We study the time evolution of a conformal field theory deformed by a relevant operator under a smooth but fast quantum quench which brings it to the conformal point. We argue that when the quench time scale δt is small compared to the scale set by the relevant coupling, the expectation value of the quenched operator scales universally as δλ/δt(2Δ-d), where δλ is the quench amplitude. This grow...