Found 3250 results, showing the newest relevant preprints. Sort by relevancy only.Update me on new preprints

Renormalized perturbation **theory** at large expansion orders

Our formalism permits to easily complement perturbation

**theory**with non-perturbative information, which we illustrate by implementing expansions renormalized by the addition of a gap or the inclusion of Dynamical Mean-**Field**Theory. Expand abstract. We present a general formalism that allows for the computation of large-order renormalized expansions in the spacetime representation, effectively doubling the numerically attainable perturbation order of renormalized Feynman diagrams. We show that this formulation compares advantageously to the currently standard techniques due to its high efficiency, simplicity, and broad range of applicability. Our formalism permits to easily complement perturbation

**theory**with non-perturbative information, which we illustrate by implementing expansions renormalized by the addition of a gap or the inclusion of Dynamical Mean-**Field****Theory**. As a result, we present numerically-exact results for the square-lattice Fermi-Hubbard model in the low temperature non-Fermi-liquid regime and show the momentum-dependent suppression of fermionic excitations in the antinodal region.3 days ago

4/10 relevant

arXiv

4/10 relevant

arXiv

Distributions in CFT I. Cross-Ratio Space

This is the first in a series of papers on distributional properties of correlation functions in conformal

**field****theory**. Expand abstract. We show that the four-point functions in conformal

**field****theory**are defined as distributions on the boundary of the region of convergence of the conformal block expansion. The conformal block expansion converges in the sense of distributions on this boundary, i.e. it can be integrated term by term against appropriate test functions. This can be interpreted as a giving a new class of functionals that satisfy the swapping property when applied to the crossing equation, and we comment on the relation of our construction to other types of functionals. Our language is useful in all considerations involving the boundary of the region of convergence, e.g. for deriving the dispersion relations. We establish our results by elementary methods, relying only on crossing symmetry and the standard convergence properties of the conformal block expansion. This is the first in a series of papers on distributional properties of correlation functions in conformal**field****theory**.4 days ago

5/10 relevant

arXiv

5/10 relevant

arXiv

A framework for geometric **field** **theories** and their classification in
dimension one

In this paper, we develop a general framework of geometric functorial field theories, meaning that all bordisms in question are endowed with a particular kind of geometric structure. Expand abstract.

In this paper, we develop a general framework of geometric functorial

**field**theories, meaning that all bordisms in question are endowed with a particular kind of geometric structure. We take particular care to establish a notion of smooth variation of geometric structures, so that it makes sense to require the output of our**field****theory**functors to depend smoothly on the input. We then test our framework on the case of $1$-dimensional**field****theories**(with or without orientation) over a manifold $M$. Here the expectation is that such a**field****theory**is equivalent to the data of a vector bundle over $M$ with connection and, in the nonoriented case, the additional data of a nondegenerate bilinear pairing; we prove that this is indeed the case in our framework.11 days ago

10/10 relevant

arXiv

10/10 relevant

arXiv

Bosonic ghostbusting -- The bosonic ghost vertex algebra admits a logarithmic module category with rigid fusion

The rank 1 bosonic ghost vertex algebra, also known as the $\beta \gamma$ ghosts, symplectic bosons or Weyl vertex algebra is a simple example of a conformal field theory which is neither rational, nor $C_2$-cofinite. Expand abstract.

The rank 1 bosonic ghost vertex algebra, also known as the $\beta \gamma$ ghosts, symplectic bosons or Weyl vertex algebra is a simple example of a conformal

**field****theory**which is neither rational, nor $C_2$-cofinite. We identify a module category, denoted category $\mathscr{F}$, which satisfies three necessary conditions coming from conformal**field****theory**considerations: closure under restricted duals, closure under fusion and closure under the action of the modular group on characters. We prove the second of these conditions, with the other two already being known. Further, we show that category $\mathscr{F}$ has sufficiently many projective and injective modules, give a classification of all indecomposable modules, show that fusion is rigid and compute all fusion products. The fusion product formulae turn out to perfectly match a previously proposed Verlinde formula, which was computed using a conjectured generalisation of the usual rational Verlinde formula, called the standard module formalism. The bosonic ghosts therefore exhibit essentially all of the rich structure of rational**theories**despite satisfying none of the standard rationality assumptions such as $C_2$-cofiniteness, the vertex algebra being isomorphic to its restricted dual or having a one-dimensional conformal weight 0 space. In particular, to the best of the authors' knowledge this is the first example of a proof of rigidity for a logarithmic non-$C_2$-cofinite vertex algebra.11 days ago

4/10 relevant

arXiv

4/10 relevant

arXiv

Detectable Optical Signatures of QED Vacuum Nonlinearities using
High-Intensity Laser **Fields**

Here, we present publication focus on all-optical signatures of quantum vacuum effects accessible in the high-intensity regime of electromagnetic

**fields**. Expand abstract. Up to date, quantum electrodynamics (QED) is the most precisely tested quantum

**field****theory**. Nevertheless, particularly in the high-intensity regime it predicts various phenomena, that so far have not directly been accessible in experiments, such as photon-photon scattering phenomena induced by quantum vacuum fluctuations. Here, we present publication focus on all-optical signatures of quantum vacuum effects accessible in the high-intensity regime of electromagnetic**fields**. We present an experimental setup to find signal photons distinguishable from the background. This configuration bases on two optical pulsed petawatt laser which generate a narrow but high-intensity scattering center. We calculate the differential number of signal photons attainable in this**field**configuration analytically and compare it with the background of the driving laser beams.11 days ago

4/10 relevant

arXiv

4/10 relevant

arXiv

Time dependence of reflected entropy in conformal **field** **theory**

We calculate the time dependence of the reflected entropy of two disconnected regions after a global quench in $(1+1)$-dimensional conformal field theories. Expand abstract.

We calculate the time dependence of the reflected entropy of two disconnected regions after a global quench in $(1+1)$-dimensional conformal

**field****theories**. We focus on conformal**field****theories**which are either rational or holographic. For the former class of theories, we find that the time evolution of the reflected entropy is the same as that of the mutual information. We discuss how this result is consistent with the quasi-particle picture of Calabrese and Cardy.11 days ago

9/10 relevant

arXiv

9/10 relevant

arXiv

Dynamical RG and Critical Phenomena in de Sitter Space

Perturbative quantum field theory in de Sitter space is known to give rise a variety of contributions that diverge with time (secular terms). Expand abstract.

Perturbative quantum

**field****theory**in de Sitter space is known to give rise a variety of contributions that diverge with time (secular terms). Despite significant progress, a complete understanding of the physical origin these divergences remains an outstanding problem. In this paper, we will study the origin of secular divergences in de Sitter space for interacting**theories**that are near attractive conformal fixed points. We show that the secular divergences are determined by the anomalous dimensions of the same**theory**in flat space and can be re-summed using the dynamical renormalization group. This behavior is mandatory at the conformal fixed point but we show that it holds away from the fixed point as well. We analyze this problem in general using conformal perturbation**theory**and study conformally coupled scalar**fields**in four and $4-\epsilon$ dimensions as examples.11 days ago

4/10 relevant

arXiv

4/10 relevant

arXiv

Canonical analysis of **field** **theories** in the presence of boundaries:
Maxwell+Pontryagin

We study the canonical Hamiltonian analysis of gauge theories in the presence of boundaries. Expand abstract.

We study the canonical Hamiltonian analysis of gauge

**theories**in the presence of boundaries. While the implementation of Dirac's program in the presence of boundaries, as put forward by Regge and Teitelboim, is not new, there are some instances in which this formalism is incomplete. Here we propose an extension to the Dirac formalism --together with the Regge-Teitelboim strategy,-- that includes generic cases of**field****theories**. We see that there are two possible scenarios, one where there is no contribution from the boundary to the symplectic structure and the other case in which there is one, depending on the dynamical details of the starting action principle. As a concrete system that exemplifies both cases, we consider a**theory**that can be seen both as defined on a four dimensional spacetime region with boundaries --the bulk**theory**--, or as a**theory**defined both on the bulk and the boundary of the region --the mixed**theory**--. The bulk**theory**is given by the 4-dimensional Maxwell + $U(1)$ Pontryagin action while the mixed one is defined by the 4-dimensional Maxwell + 3-dimensional $U(1)$ Chern-Simons action on the boundary. Finally, we show how these two descriptions of the same system are connected through a canonical transformation that provides a third description. The focus here is in defining a consistent formulation of all three descriptions, for which we rely on the geometric formulation of constrained systems, together with the extension of the Dirac-Regge-Teitelboim (DRT) formalism put forward in the manuscript.11 days ago

7/10 relevant

arXiv

7/10 relevant

arXiv

Decay of Correlation Rate in the Mean **Field** Limit of Point Vortices
Ensembles

It is a classical result that in such limit correlations functions converge to 1, that is, point vortices decorrelate: we compute the rate at which this convergence takes place by means of Gaussian integration techniques, inspired by the correspondence between the 2-dimensional Coulomb gas and the Sine-Gordon Euclidean

**field****theory**.... Expand abstract. We consider the Mean

**Field**limit of Gibbsian ensembles of 2-dimensional point vortices on the torus. It is a classical result that in such limit correlations functions converge to 1, that is, point vortices decorrelate: we compute the rate at which this convergence takes place by means of Gaussian integration techniques, inspired by the correspondence between the 2-dimensional Coulomb gas and the Sine-Gordon Euclidean**field****theory**.13 days ago

4/10 relevant

arXiv

4/10 relevant

arXiv

Density Formalism for Quantum **Theory**

The new formalism, developed first for the single-particle case, has the advantage of generalizing immediately to quantum

**field****theory**and to the description of relativistic phenomena such as particle creation and annihilation. Expand abstract. A simple mathematical extension of quantum

**theory**is presented. As well as opening the possibility of alternative methods of calculation, the additional formalism implies a new physical interpretation of the standard**theory**by providing a picture of an external reality. The new formalism, developed first for the single-particle case, has the advantage of generalizing immediately to quantum**field****theory**and to the description of relativistic phenomena such as particle creation and annihilation.13 days ago

4/10 relevant

arXiv

4/10 relevant

arXiv