Renormalization group crossover in the critical dynamics of field theories with mode coupling terms

Motivated by the collective behavior of biological swarms, we study the critical dynamics of field theories with coupling between order parameter and conjugate momentum in the presence of dissipation. Under a fixed-network approximation, we perform a dynamical renormalization group calculation at on...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Cavagna, Andrea, Di Carlo, Luca, Giardina, Irene, Grandinetti, Luca, Grigera, Tomás Sebastián, Pisegna, Giulia
Formato: Articulo
Lenguaje:Inglés
Publicado: 2019
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/139061
Aporte de:
id I19-R120-10915-139061
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Exactas
Física
Biología
biological swarms
dynamics of field theories
dissipation
spellingShingle Ciencias Exactas
Física
Biología
biological swarms
dynamics of field theories
dissipation
Cavagna, Andrea
Di Carlo, Luca
Giardina, Irene
Grandinetti, Luca
Grigera, Tomás Sebastián
Pisegna, Giulia
Renormalization group crossover in the critical dynamics of field theories with mode coupling terms
topic_facet Ciencias Exactas
Física
Biología
biological swarms
dynamics of field theories
dissipation
description Motivated by the collective behavior of biological swarms, we study the critical dynamics of field theories with coupling between order parameter and conjugate momentum in the presence of dissipation. Under a fixed-network approximation, we perform a dynamical renormalization group calculation at one loop in the near-critical disordered region, and we show that the violation of momentum conservation generates a crossover between an unstable fixed point, characterized by a dynamic critical exponent z = d/2, and a stable fixed point with z = 2. Interestingly, the two fixed points have different upper critical dimensions. The interplay between these two fixed points gives rise to a crossover in the critical dynamics of the system, characterized by a crossover exponent κ = 4/d. The crossover is regulated by a conservation length scale R0, given by the ratio between the transport coefficient and the effective friction, which is larger as the dissipation is smaller: Beyond R0, the stable fixed point dominates, while at shorter distances dynamics is ruled by the unstable fixed point and critical exponent, a behavior which is all the more relevant in finite-size systems with weak dissipation. We run numerical simulations in three dimensions and find a crossover between the exponents z = 3/2 and z = 2 in the critical slowdown of the system, confirming the renormalization group results. From the biophysical point of view, our calculation indicates that in finite-size biological groups mode coupling terms in the equation of motion can significantly change the dynamical critical exponents even in the presence of dissipation, a step toward reconciling theory with experiments in natural swarms. Moreover, our result provides the scale within which fully conservative Bose-Einstein condensation is a good approximation in systems with weak symmetry-breaking terms violating number conservation, as quantum magnets or photon gases.
format Articulo
Articulo
author Cavagna, Andrea
Di Carlo, Luca
Giardina, Irene
Grandinetti, Luca
Grigera, Tomás Sebastián
Pisegna, Giulia
author_facet Cavagna, Andrea
Di Carlo, Luca
Giardina, Irene
Grandinetti, Luca
Grigera, Tomás Sebastián
Pisegna, Giulia
author_sort Cavagna, Andrea
title Renormalization group crossover in the critical dynamics of field theories with mode coupling terms
title_short Renormalization group crossover in the critical dynamics of field theories with mode coupling terms
title_full Renormalization group crossover in the critical dynamics of field theories with mode coupling terms
title_fullStr Renormalization group crossover in the critical dynamics of field theories with mode coupling terms
title_full_unstemmed Renormalization group crossover in the critical dynamics of field theories with mode coupling terms
title_sort renormalization group crossover in the critical dynamics of field theories with mode coupling terms
publishDate 2019
url http://sedici.unlp.edu.ar/handle/10915/139061
work_keys_str_mv AT cavagnaandrea renormalizationgroupcrossoverinthecriticaldynamicsoffieldtheorieswithmodecouplingterms
AT dicarloluca renormalizationgroupcrossoverinthecriticaldynamicsoffieldtheorieswithmodecouplingterms
AT giardinairene renormalizationgroupcrossoverinthecriticaldynamicsoffieldtheorieswithmodecouplingterms
AT grandinettiluca renormalizationgroupcrossoverinthecriticaldynamicsoffieldtheorieswithmodecouplingterms
AT grigeratomassebastian renormalizationgroupcrossoverinthecriticaldynamicsoffieldtheorieswithmodecouplingterms
AT pisegnagiulia renormalizationgroupcrossoverinthecriticaldynamicsoffieldtheorieswithmodecouplingterms
bdutipo_str Repositorios
_version_ 1764820456969338881