Generalized Symmetries for Generalized Gravitons.

Phys Rev Lett

Instituto Balseiro, Centro Atómico Bariloche, 8400 San Carlos de Bariloche, Río Negro, Argentina.

Published: September 2023

AI Article Synopsis

  • The study develops generalized symmetries for linearized Einstein gravity across different dimensions, highlighting the emergence of dual pairs in quantum field theory.
  • It identifies a complete set of nontrivial conserved charges linked to specific currents, totaling D(D+1) charges, and computes their quantum commutators, which show non-zero values when regions are linked.
  • The research also examines higher-curvature gravities, revealing additional modes and ensuring that the absence of a ghostlike spin-2 mode maintains unitarity and preserves the dual-pairs principle.

Article Abstract

We construct generalized symmetries for linearized Einstein gravity in arbitrary dimensions. First-principle considerations in quantum field theory force generalized symmetries to appear in dual pairs. Verifying this prediction helps us find the full set of nontrivial conserved charges-associated, in equal parts, with 2-form and (D-2)-form currents. Their total number is D(D+1). We compute the quantum commutators of pairs of dual charges, showing that they are nonvanishing for regions whose boundaries are nontrivially linked with each other and zero otherwise, as expected on general grounds. We also consider general linearized higher-curvature gravities. These propagate, in addition to the usual graviton, a spin-0 mode as well as a massive ghostlike spin-2 mode. When the latter is absent, the theory is unitary and the dual-pairs principle is respected. In particular, we find that the number and types of charges remain the same as for Einstein gravity, and that they correspond to continuous generalizations of the Einsteinian ones.

Download full-text PDF

Source
http://dx.doi.org/10.1103/PhysRevLett.131.111603DOI Listing

Publication Analysis

Top Keywords

generalized symmetries
12
einstein gravity
8
generalized
4
symmetries generalized
4
generalized gravitons
4
gravitons construct
4
construct generalized
4
symmetries linearized
4
linearized einstein
4
gravity arbitrary
4

Similar Publications

Motor synergy and energy efficiency emerge in whole-body locomotion learning.

Sci Rep

January 2025

Neuro-Robotics Lab, Department of Robotics, Graduate School of Engineering, Tohoku University, Sendai, Japan.

Humans exploit motor synergies for motor control; however, how they emerge during motor learning is not clearly understood. Few studies have dealt with the computational mechanism for generating synergies. Previously, optimal control generated synergistic motion for the upper limb; however, it has not yet been applied to the high-dimensional whole-body system.

View Article and Find Full Text PDF

Massive Dirac fermions, which are essential for realizing novel topological phenomena, are expected to be generated from massless Dirac fermions by breaking the related symmetry, such as time-reversal symmetry in topological insulators or crystal symmetry in topological crystalline insulators. Here, we report scanning tunneling microscopy and angle-resolved photoemission spectroscopy studies of α-Bi_{4}I_{4}, which reveals the realization of massive Dirac fermions in the (100) surface states without breaking the time-reversal symmetry. Combined with first-principles calculations, our experimental results indicate that the spontaneous symmetry breaking engenders two nondegenerate edge states at the opposite sides of monolayer Bi_{4}I_{4} after the structural phase transition, imparting mass to the Dirac fermions after taking the interlayer coupling into account.

View Article and Find Full Text PDF

Background: Grid cells are spatially modulated cells in the entorhinal cortex (EC) that fire in a hexagonally patterned grid which tiles the environment. These cells are assumed important in human spatial navigation. The EC is vulnerable to neurodegenerative processes in both normal aging and Alzheimer's disease and decline in grid cell function may be a key factor in understanding age-related navigational decline.

View Article and Find Full Text PDF

In this work we analytically investigate the alignment mechanism of self-propelled ellipse-shaped cells in two spatial dimensions interacting via overlap avoidance. By considering a two-cell system and imposing certain symmetries, we obtain an analytically tractable dynamical system, which we mathematically analyse in detail. We find that for elongated cells there is a half-stable steady state corresponding to perfect alignment between the cells.

View Article and Find Full Text PDF

Stacking-Engineered Ferroelectricity and Multiferroic Order in van der Waals Magnets.

Phys Rev Lett

December 2024

John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, USA.

Two-dimensional (2D) materials that exhibit spontaneous magnetization, polarization, or strain (referred to as ferroics) have the potential to revolutionize nanotechnology by enhancing the multifunctionality of nanoscale devices. However, multiferroic order is difficult to achieve, requiring complicated coupling between electron and spin degrees of freedom. We propose a universal method to engineer multiferroics from van der Waals magnets by taking advantage of the fact that changing the stacking between 2D layers can break inversion symmetry, resulting in ferroelectricity as well as magnetoelectric coupling.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!