Dona, Pietro Fanizza, Marco Sarno, Giorgio Speziale, Simone

The Lorentzian EPRL spin foam amplitude for loop quantum gravity is a multi-dimensional non-compact integral of highly oscillating functions. Using a method based on the decomposition of Clebsch-Gordan coefficients for the unitary infinite-dimensional representations of SL(2,C) in terms of those of SU(2), we are able to provide for the first time n...

Jeong, Saebyeok Lee, Norton Nekrasov, Nikita

We explore the $\textit{difference Langlands correspondence}$ using the four dimensional ${\mathcal{N}}=2$ super-QCD. Surface defects and surface observables play the crucial role. As an application, we give the first construction of the full set of quantum integrals, i.e. commuting differential operators, such that the partition function of the so...

Jeong, Saebyeok Lee, Norton

We study two types of surface observables $-$ the $\mathbf{Q}$-observables and the $\mathbf{H}$-observables $-$ of the 4d $\mathcal{N}=2$$A_1$-quiver $U(N)$ gauge theory obtained by coupling a 2d $\mathcal{N}=(2,2)$ gauged linear sigma model. We demonstrate that the transition between the two surface defects manifests as a Fourier transformation be...

Albayrak, Omer Vachaspati, Tanmay

We consider the creation of kink-antikink pairs of a scalar field $\phi$ by the scattering of classical wavepackets of a second scalar field, $\psi$, when there are no direct interactions between $\phi$ and $\psi$. The creation becomes possible only due to a quantum field that interacts with both $\phi$ and $\psi$. We scan parameter space and find ...

Cohen, Timothy Lu, Xiaochuan Zhang, Zhengkang

We revisit the calculation of anomalies for global and gauge symmetries in the framework of the Covariant Derivative Expansion (CDE). Due to the presence of UV divergences, the result is an ambiguous quantity that depends on the regularization procedure and the renormalization scheme. We introduce a class of regulators that facilitate a straightfor...

Critelli, Renato Rougemont, Romulo Noronha, Jorge
Published in
Journal of High Energy Physics

We use holography to investigate the process of homogeneous isotropization and thermalization in a strongly coupled N=4\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$ ...

Álvarez-Gaumé, Luis Chaichian, Moshe M. Oksanen, Markku A. Tureanu, Anca

The CPT theorem originally proven by L\"uders and Pauli ensures the equality of masses, lifetimes, magnetic moments and cross sections of any particle and its antiparticle. We show that in a Lorentz invariant quantum field theory described by its Lagrangian, CPT-violating interaction alone does not split the masses of an elementary particle and its...

Rovelli, Carlo Zatloukal, Václav

We sharpen a recent observation by Tim Maudlin: differential calculus is a natural language for physics only if additional structure, like the definition of a Hodge dual or a metric, is given; but the discrete version of this calculus provides this additional structure for free.

Alvarez-Gaume, Luis Vazquez-Mozo, Miguel A.

Anomalies are a very powerful tool in constraining theories beyond the standard model. We give a pedagogical overview of some topics illustrating the important role played by spacetime anomalies in string theory. After discussing the general problem of anomaly cancellation in quantum field theory, the focus is set on the cancellation of anomalies i...

Komatsu, Shota Martina, Adrien Penedones, João Suchel, Noé Vuignier, Antoine Zhao, Xiang

We revisit the Berenstein-Maldacena-Nastase (BMN) conjecture relating M-theory on a PP-wave background and Matrix Quantum Mechanics (MQM) of $N\times N$ matrices. In particular, we study the BMN MQM at strong coupling and finite $N$ and derive an effective Hamiltonian that describes non-relativistic free particles in a harmonic trap. The energy spe...