299 citations · 329 across the 19 of their papers we have counts for
20 papers
Gravitational Waves and Matter Constraints in Gravity from Entropy
David S. Pereira
We show that Gravity from Entropy (GfE) exhibits a tensor-propagation pathology on generic FLRW backgrounds. In vacuum, in the symmetry-inheriting single-multiplet sector, and for…
Jordan-like invariant representations of scalar-tensor gravity and the return of imperfect-fluid thermodynamics
David S. Pereira, José Pedro Mimoso
It has been shown that the thermodynamics of frame-invariant scalar-tensor gravity admits an Einstein-frame-like invariant representation, in which the scalar sector is minimally c…
A Buchdahl solution generator for Einstein-sigma gravity and multiscalar-tensor gravity
David S. Pereira, Francisco S. N. Lobo, José Pedro Mimoso
Buchdahl transformations provide a geometric route from vacuum spacetimes to scalar-field solutions. We formulate this mechanism as a target-covariant solution generator for Einste…
Gravitational Waves as Thermodynamic Shear Excitations in Scalar-Tensor Gravity
David S. Pereira
Can a propagating spin--2 mode participate in a local thermodynamic process without assigning an autonomous entropy or a unique local energy to the wave itself? We show that this o…
Differential Obstructions to Curvature-Dependent Conformal Transformations
David S. Pereira, Francisco S. N. Lobo, José Pedro Mimoso
Curvature-dependent conformal rules are local forward assignments on known metrics, but they are not generically local changes of metric variables. We study the nondegenerate class…
Vacuum Gravity from Entropy: Stability, Spectra, and Exact Waves
David S. Pereira
We analyze the vacuum dynamics of Gravity from Entropy, including its algebraically constrained -field formulation. Evaluating the curvature traces over zero-, one-, and two-for…
Gravitational baryogenesis beyond the spectator approximation
David S. Pereira, Beatriz A. Fernandes, José Pedro Mimoso
The standard gravitational-baryogenesis operator , with , is usually treated as a spectator interaction that generates an effective chemica…
Thermal channels of scalar and tensor waves in Jordan-frame scalar--tensor gravity
David S. Pereira, Francisco S. N Lobo, José Pedro Mimoso
We study first-order scalar and tensor perturbations of Jordan-frame scalar--tensor gravity about a spatially flat FLRW background using the Einstein-like effective-fluid decomposi…
First-order thermodynamics of multi-scalar-tensor gravity
David S. Pereira
We formulate a first-order thermodynamic description of Jordan-frame tensor--multi-scalar gravity. We derive the exact covariant split of the geometric sector and recast it a…
Eckart heat-flux applicability in theories and the existence of temperature gradients
David S. Pereira, José Pedro Mimoso
We show that in single--scalar theories of the form , a generic nonminimal coupling induces, in the scalar--comoving frame, an additional trans…
Novel scalar degrees of freedom emerging from hybrid metric-Palatini gravity
David S. Pereira, Salvatore Capozziello, Francisco S. N Lobo +1
Hybrid metric-Palatini gravity unifies the metric and Palatini formalisms while preserving a propagating scalar degree of freedom, offering a compelling route to modified gravity c…
Big Bang Nucleosynthesis constraints on gravity
Daniel F. P. Cruz, David S. Pereira, Francisco S. N. Lobo +1
We investigate Big Bang Nucleosynthesis (BBN) in the framework of gravity, where the gravitational Lagrangian depends on the torsion scalar and the matter Lagrangian…
Gravitational baryogenesis in gravity
Daniel F. P. Cruz, David S. Pereira, Francisco S. N. Lobo
The observed matter-antimatter asymmetry of the Universe remains a fundamental challenge in modern physics. In this work, we explore gravitational baryogenesis within the framework…
Baryon asymmetry from higher-order matter contributions in gravity
David S. Pereira, Francisco S. N. Lobo, José Mimoso
We investigate the observed asymmetry between matter and antimatter by incorporating higher-order matter contributions in gravity, specifically analyzing gravitational baryogenesis…
The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
Eleonora Di Valentino, Jackson Levi Said, Adam Riess +533
The standard model of cosmology has provided a good phenomenological description of a wide range of observations both at astrophysical and cosmological scales for several decades.…
Scalar-tensor baryogenesis: a scalar-tensor completion of gravitational baryogenesis
David S. Pereira
We propose \emph{Scalar-Tensor Baryogenesis} (STB), in which the -violating bias needed for baryogenesis is sourced by the \emph{gravitational} scalars that appear in scalar-…
Thermodynamics of the Primordial Universe
David S. Pereira, João Ferraz, Francisco S. N. Lobo +1
This review delves into the pivotal primordial stage of the universe, a period that holds the key to understanding its current state. To fully grasp this epoch, it is essential to…
Gravitational Baryogenesis in Energy-Momentum Squared~Gravity
David S. Pereira, Francisco S. N. Lobo, José Pedro Mimoso
We demonstrate that the matter sector itself can drive baryogenesis in energy-momentum squared gravity, with . High-density mat…
Extension of Buchdahl's Theorem on Reciprocal Solutions
David S. Pereira, José Pedro Mimoso, Francisco S. N. Lobo
Since the development of Brans-Dicke gravity, it has become well-known that a conformal transformation of the metric can reformulate this theory, transferring the coupling of the s…
Baryogenesis: A Symmetry Breaking in the Primordial Universe Revisited
David S. Pereira, João Ferraz, Francisco S. N. Lobo +1
In this review article, we revisit the topic of baryogenesis, which is the physical process that generated the observed baryon asymmetry during the first stages of the primordial U…