116 citations · 1.1k across the 21 of their papers we have counts for
21 papers
Reverse Bootstrapping: IR lessons for UV physics
Lasma Alberte, Claudia de Rham, Sumer Jaitly +1
S-matrix bootstrap and positivity bounds are usually viewed as constraints on low-energy theories imposed by the requirement of a standard UV completion. By considering graviton--p…
QED positivity bounds
Lasma Alberte, Claudia de Rham, Sumer Jaitly +1
We apply positivity bounds directly to a gauge theory with charged scalars and charged fermions, i.e. QED, minimally coupled to gravity. Assuming that the massless -chann…
Positivity Bounds and the Massless Spin-2 Pole
Lasma Alberte, Claudia de Rham, Sumer Jaitly +1
The presence of a massless spin-2 field in an effective field theory results in a -channel pole in the scattering amplitudes that precludes the application of standard positivit…
Spontaneously broken boosts and the Goldstone continuum
Lasma Alberte, Alberto Nicolis
The spontaneous breaking of boost invariance is ubiquitous in nature, yet the associated Goldstone bosons are nowhere to be seen. We discuss why some subtleties are to be expected…
Positivity Constraints on Interacting Pseudo-Linear Spin-2 Fields
Lasma Alberte, Claudia de Rham, Arshia Momeni +2
We explore the effective field theory for single and multiple interacting pseudo-linear spin-2 fields. By applying forward limit positivity bounds, we show that among the parameter…
Positivity Constraints on Interacting Spin-2 Fields
Lasma Alberte, Claudia de Rham, Arshia Momeni +2
The consistency of the EFT of two interacting spin-2 fields is checked by applying forward limit positivity bounds on the scattering amplitudes to exclude the region of parameter s…
EFT of Interacting Spin-2 Fields
Lasma Alberte, Claudia de Rham, Arshia Momeni +2
We consider the effective field theory of multiple interacting massive spin-2 fields. We focus on the case where the interactions are chosen so that the cutoff is the highest possi…
Equivalence Principle on Cosmological Backgrounds in Scalar-Tensor Theories
Lasma Alberte
We study the extent up to which the equivalence principle is obeyed in models of modified gravity and dark energy involving a single scalar degree of freedom. We focus on the effec…
Elasticity bounds from Effective Field Theory
Lasma Alberte, Matteo Baggioli, Victor Cancer Castillo +1
Phonons in solid materials can be understood as the Goldstone bosons of the spontaneously broken spacetime symmetries. As such their low energy dynamics are greatly constrained and…
Holographic Phonons
Lasma Alberte, Martin Ammon, Matteo Baggioli +2
We present a class of holographic massive gravity models that realize a spontaneous breaking of translational symmetry - they exhibit transverse phonon modes whose speed relates to…
Black hole elasticity and gapped transverse phonons in holography
Lasma Alberte, Martin Ammon, Matteo Baggioli +2
We study the elastic response of planar black hole (BH) solutions in a simple class of holographic models with broken translational invariance. We compute the transverse quasi-norm…
Relaxing the Cosmological Constant: a Proof of Concept
Lasma Alberte, Paolo Creminelli, Andrei Khmelnitsky +2
We propose a technically natural scenario whereby an initially large cosmological constant (c.c.) is relaxed down to the observed value due to the dynamics of a scalar evolving on…
Viscosity bound violation in holographic solids and the viscoelastic response
Lasma Alberte, Matteo Baggioli, Oriol Pujolas
We argue that the Kovtun--Son--Starinets (KSS) lower bound on the viscosity to entropy density ratio holds in fluid systems but is violated in solid materials with a non-zero shear…
Solid Holography and Massive Gravity
Lasma Alberte, Matteo Baggioli, Andrei Khmelnitsky +1
Momentum dissipation is an important ingredient in condensed matter physics that requires a translation breaking sector. In the bottom-up gauge/gravity duality, this implies that t…
Density matrix of black hole radiation
Lasma Alberte, Ram Brustein, Andrei Khmelnitsky +1
Hawking's model of black hole evaporation is not unitary and leads to a mixed density matrix for the emitted radiation, while the Page model describes a unitary evaporation process…
Stability of Massive Gravity Solutions for Holographic Conductivity
Lasma Alberte, Andrei Khmelnitsky
We consider non-linear massive gravity with two Stückelberg fields in which the diffeomorphism invariance is broken spontaneously in two of the spacetime directions. This theory ad…
Reduced Massive Gravity with Two Stückelberg Fields
Lasma Alberte, Andrei Khmelnitsky
We consider the non-linear massive gravity as a theory of a number of Stückelberg scalar fields minimally coupled to the Einstein-Hilbert gravity and argue that the counting of deg…
Semiclassical Calculation of Multiparticle Scattering Cross Sections in Classicalizing Theories
Lasma Alberte, Fedor Bezrukov
It has been suggested in arXiv:1010.1415 that certain derivatively coupled non-renormalizable scalar field theories might restore the perturbative unitarity of high energy hard sca…
Massive Gravity on Curved Background
Lasma Alberte
We investigate generally covariant theories which admit a Fierz-Pauli mass term for metric perturbations around an arbitrary curved background. For this we restore the general cova…
Massive Gravity: Exorcising the Ghost
Lasma Alberte, Ali H. Chamseddine, Viatcheslav Mukhanov
We consider Higgs massive gravity [1,2] and investigate whether a nonlinear ghost in this theory can be avoided. We show that although the theory considered in [10,11] is ghost fre…
Massive Gravity: Resolving the Puzzles
Lasma Alberte, Ali H. Chamseddine, Viatcheslav Mukhanov
We consider the massless limit of Higgs gravity, where the graviton becomes massive when the scalar fields acquire expectation values. We determine the Vainshtein scale and prove t…