52 citations · 389 across the 22 of their papers we have counts for
22 papers
On the Relative Distance of Entangled Systems in Emergent Spacetime Scenarios
Guilherme Franzmann, Sebastian M. D. Jovancic, Matthew Lawson
Spacetime emergence from entanglement proposes an alternative to quantizing gravity and typically derives a notion of distance based on the amount of mutual information shared acro…
Modified gravity approaches to the cosmological constant problem
The FADE Collaboration, Heliudson Bernardo, Benjamin Bose +5
The cosmological constant and its phenomenology remain among the greatest puzzles in theoretical physics. We review how modifications of Einstein's general relativity could allevia…
Kalb-Ramond backgrounds in -complete cosmology
Heliudson Bernardo, Paul R. Chouha, Guilherme Franzmann
We study the matter-coupled equations of motion for cosmological NS massless fields including all corrections in an O duality invariant approach, with emphasis on the K…
Cosmology at the top of the tower
Jerome Quintin, Heliudson Bernardo, Guilherme Franzmann
The cosmology of the fully -corrected duality-invariant action for the Neveu-Schwarz sector of string theory is revisited, with special emphasis on its coupling to matter sourc…
Solution of the Size and Horizon Problems from Classical String Geometry
Heliudson Bernardo, Robert Brandenberger, Guilherme Franzmann
In a recent paper we developed a string cosmology background from classical string geometry. Here, we show that this background yields a solution to the size and horizon problems o…
String Cosmology backgrounds from Classical String Geometry
Heliudson Bernardo, Robert Brandenberger, Guilherme Franzmann
We introduce a very early universe model based on the thermodynamics of a gas of closed strings in a background which is non-perturbative in . Upon considering the fully -c…
-Cosmology: solutions and stability analysis
Heliudson Bernardo, Guilherme Franzmann
We review O Covariant String Cosmology to all orders in in the presence of matter and study its solutions. We show that the perturbative analysis for a constant dilaton…
Unified Superfluid Dark Sector
Elisa G. M. Ferreira
In this talk I present a new model of a unified dark sector, where late-time cosmic acceleration emerges from the dark matter (DM) superfluid framework. We will start by reviewing…
O covariant String Cosmology to all orders in
Heliudson Bernardo, Robert Brandenberger, Guilherme Franzmann
Recently, all duality invariant -corrections to the massless NS-NS sector of string theory on time-dependent backgrounds were classified and the form of their contribution to t…
A democratic Cosmos?
Yigit Yargic, Guilherme Franzmann
Despite the success of our best models in Theoretical Physics, especially concerning Cosmology and Particle Physics, we still face persistent challenges. Among them we have the cos…
completion of the Friedmann equations
Stephen Angus, Kyoungho Cho, Guilherme Franzmann +2
In string theory the closed-string massless NS-NS sector forms a multiplet of symmetry. This suggests a specific modification to General Relativity in which the e…
A local Lagrangian for MOND as modified inertia
Renato Costa, Guilherme Franzmann, Jonas P. Pereira
We propose a local Lagrangian for a point particle where its inertia part is modified in the regime of small accelerations. For the standard gravitational central force, it recover…
T-Dual Cosmological Solutions of Double Field Theory II
Heliudson Bernardo, Robert Brandenberger, Guilherme Franzmann
In this paper we present cosmological solutions of Double Field Theory in the supergravity frame and in the winding frame which are related via T-duality. In particular, we show th…
Unified Superfluid Dark Sector
Elisa G. M. Ferreira, Guilherme Franzmann, Justin Khoury +1
We present a novel theory of a unified dark sector, where late-time cosmic acceleration emerges from the dark matter superfluid framework. The system is described by a superfluid m…
T-dual cosmological solutions in double field theory
Robert Brandenberger, Renato Costa, Guilherme Franzmann +1
We investigate the cosmological solutions coming from the double field theory equations of motion after coupling a matter source to them. Assuming constant dilaton and imposing the…
Dual Space-Time and Nonsingular String Cosmology
Robert Brandenberger, Renato Costa, Guilherme Franzmann +1
Making use of the T-duality symmetry of superstring theory, and of the double geometry from Double Field Theory, we argue that cosmological singularities of a homogeneous and isotr…
Point Particle Motion in DFT and a Singularity-Free Cosmological Solution
Robert Brandenberger, Renato Costa, Guilherme Franzmann +1
We generalize the action for point particle motion to a double field theory background. After deriving the general equations of motion for these particle geodesics, we specialize t…
Running of the Spectrum of Cosmological Perturbations in String Gas Cosmology
Robert Brandenberger, Guilherme Franzmann, Qiuyue Liang
We compute the running of the spectrum of cosmological perturbations in String Gas Cosmology, making use of a smooth parametrization of the transition between the early Hagedorn ph…
Covariant c-flation: a variational approach
Renato Costa, Rodrigo R. Cuzinatto, Elisa. M. G. Ferreira +1
We develop an action principle to construct the dynamics that give rise to a minimal generalization of Einstein's equations, where the speed of light (), the gravitational const…
Varying fundamental constants: a full covariant approach and cosmological applications
Guilherme Franzmann
We build a minimal extension of General Relativity in which Newton's gravitational coupling, , the speed of light, , and the cosmological constant, , are spacetime variabl…
Atomic beings and the discovery of gravity
George De Conto, Guilherme Franzmann
We aim to bring a new perspective about some aspects of the current research in Cosmology. We start with a brief introduction about the main developments of the field in the last c…
Can Back-Reaction Prevent Eternal Inflation?
Robert Brandenberger, Renato Costa, Guilherme Franzmann
We study the effects which the back-reaction of long wavelength fluctuations exert on stochastic inflation. In the cases of power-law and Starobinsky inflation these effects are to…