Publications de Alexander Monin

Flux correlators and semiclassics

Riccardo Rattazzi, Alexander Monin, Eren Clément Firat, Matthew Thomas Walters

We consider correlators for the flux of energy and charge in the background of operators with large global U(1) charge in conformal field theory (CFT). It has recently been shown that the corresponding Euclidean correlators generically admit a semiclassica ...

Springer Nature2024

Identifying Large Charge operators

Riccardo Rattazzi, Alexander Monin, Gil Badel

The Large Charge sector of Conformal Field Theory (CFT) can generically be described through a semiclassical expansion around a superfluid background. In this work, focussing on U(1) invariant Wilson-Fisher fixed points, we study the spectrum of spinning l ...

Springer Nature2023

More on the operator-state map in nonrelativistic CFTs

Alexander Monin

We propose an algebraic construction of the operator-state correspondence in nonrelativistic conformal field theories by explicitly constructing an automorphism of the Schrodinger algebra relating generators in different frames. It is shown that the constr ...

American Physical Society2022

Gapped Goldstones at the cut-off scale: a non-relativistic EFT

Riccardo Rattazzi, Alexander Monin, Gabriel Francisco Cuomo, Angelo Esposito

At finite density, the spontaneous breakdown of an internal non-Abelian symmetry dictates, along with gapless modes, modes whose gap is fixed by the algebra and proportional to the chemical potential: the gapped Goldstones. Generically the gap of these sta ...

Springer Nature2021

Feynman diagrams and the large charge expansion in 3-epsilon dimensions

Riccardo Rattazzi, Alexander Monin, Gil Badel, Gabriel Francisco Cuomo

In arXiv:1909.01269 it was shown that the scaling dimension of the lightest charge n operator in the U (1) model at the Wilson-Fisher fixed point in D = 4 - epsilon can be computed semiclassically for arbitrary values of lambda n, where lambda is the pertu ...

2020

The epsilon expansion meets semiclassics

Riccardo Rattazzi, Alexander Monin, Gil Badel, Gabriel Francisco Cuomo

We study the scaling dimension Delta(phi n) of the operator phi(n) where phi is the fundamental complex field of the U(1) model at the Wilson-Fisher fixed point in d = 4 - epsilon. Even for a perturbatively small fixed point coupling lambda*, standard pert ...

Springer Nature2019

Rotating superfluids and spinning charged operators in conformal field theory

Riccardo Rattazzi, Alexander Monin, David Pirtskhalava, Anton Reyes De La Fuente, Gabriel Francisco Cuomo

American Physical Society2018

Semiclassics, Goldstone bosons and CFT data

Riccardo Rattazzi, Alexander Monin, Fiona Katharina Seibold, David Pirtskhalava

Hellerman et al. (arXiv:1505.01537) have shown that in a generic CFT the spectrum of operators carrying a large U(1) charge can be analyzed semiclassically in an expansion in inverse powers of the charge. The key is the operator state correspondence by whi ...

Springer Nature2017

Gauging nonrelativistic field theories using the coset construction

Alexander Monin, Georgios Karananas

We discuss how nonrelativistic spacetime symmetries can be gauged in the context of the coset construction. We consider theories invariant under the centrally extended Galilei algebra as well as the Lifshitz one, and we investigate under what conditions th ...

American Physical Society2016

Weyl vs. conformal

Alexander Monin, Georgios Karananas

In this note we show that given a conformally invariant theory in flat space-time, it is not always possible to couple it to gravity in a Weyl invariant way. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY li ...

Elsevier2016

Partition function on spheres: How to use zeta function regularization

Alexander Monin

It is known that not all summation methods are linear and stable. Zeta function regularization is in general nonlinear. However, in some cases formal manipulations with zeta function regularization (assuming linearity of sums) lead to correct results. We c ...

American Physical Society2016

Weyl and Ricci gauging from the coset construction

Alexander Monin, Georgios Karananas

In this paper we demonstrate how, using the coset construction, a theory can be systematically made Weyl invariant by gauging the scale symmetry. We show that an analog of the inverse Higgs constraint allows the elimination of the Weyl vector (gauge) field ...

American Physical Society2016

Evidence From Imaging Studies For Oxidative Stress Mechanisms In First Episode Schizophrenia

Jean-Philippe Thiran, Patric Hagmann, Rolf Gruetter, Lijing Xin, João Miguel das Neves Duarte, Alessandra Griffa, Yohan Van de Looij, Alexander Monin, Alberto Corcoba, Kim Do

Oxford Univ Press2015

Perturbative conformal symmetry and dilaton

Frédéric Gretsch, Alexander Monin

Spontaneous symmetry breaking with necessity leads to the presence of Goldstone field(s). In the case of scale or conformal symmetries the corresponding Goldstone mode is called the dilaton. Consistently coupling a system to the dilaton poses certain diffi ...

American Physical Society2015

(Re-)inventing the relativistic wheel: gravity, cosets, and spinning objects

Francesco Riva, Alexander Monin, Solomon G Shamsuddin Osman Endlich

Space-time symmetries are a crucial ingredient of any theoretical model in physics. Unlike internal symmetries, which may or may not be gauged and/or spontaneously broken, space-time symmetries do not admit any ambiguity: they are gauged by gravity, and an ...

Springer Nature2014

General coordinate invariance in quantum many-body systems

Alexander Monin, Solomon G Shamsuddin Osman Endlich

We extend the notion of general coordinate invariance to many-body, not necessarily relativistic, systems. As an application, we investigate nonrelativistic general covariance in Galilei-invariant systems. The peculiar transformation rules for the backgrou ...

American Physical Society2014

On the effective operators for Dark Matter annihilations

Andrea Thamm, Alexander Monin, Andrea De Simone

We consider effective operators describing Dark Matter (DM) interactions with Standard Model fermions. In the non-relativistic limit of the DM field, the operators can be organized according to their mass dimension and their velocity behaviour, i.e. whethe ...

Iop Publishing Ltd2013

Spontaneously broken scale invariance and minimal fields of canonical dimensionality

Mikhail Chapochnikov, Alexander Monin

We address the question whether a scale invariant theory can contain interacting minimal fields of canonical dimensionality. It is known that the answer to this question is negative provided the scale symmetry is respected by the ground state. We present a ...

American Physical Society2013

Spontaneously broken conformal symmetry: dealing with the trace anomaly

Mikhail Chapochnikov, Alexander Monin, Roberta Armillis

The majority of renormalizable field theories possessing the scale invariance at the classical level exhibits the trace anomaly once quantum corrections are taken into account. This leads to the breaking of scale and conformal invariance. At the same time ...

Springer Nature2013

Cecotti-Fendley-Intriligator-Vafa index in a box

Alexander Monin

The Cecotti-Fendley-Intriligator-Vafa (CFIV) index in two-dimensional N = (2,2) models is revisited. We address the problem of "elementary" (nontopological) excitations over a kink solution, in the one-kink sector (using the Wess-Zumino or Landau-Ginzburg ...

2012