Related papers: A few more comments on secularly growing loop corr…
We show that the leading derivative corrections to the Heisenberg-Euler effective action can be determined efficiently from the vacuum polarization tensor evaluated in a homogeneous constant background field. After deriving the explicit…
We continue the program [1] of carving out the space of large $N$ confining gauge theories by modern S-matrix bootstrap methods, with the ultimate goal of cornering large $N$ QCD. In this paper, we focus on the effective field theory of…
Conformal theories with a global symmetry may be studied in the double scaling regime where the interaction strength is reduced while the global charge increases. Here, we study generic 4d $\mathcal N=2$ $SU(N)$ gauge theories with…
QED formulated in prescribed classical background electromagnetic fields is a standard framework for strong-field and laser\textendash matter interactions. It is usually treated as a theory modified by externally imposed fields, obscuring…
We study the non-linear corrections to the matter and velocity power spectra in the synchronous gauge (SG). We consider the perturbations up to third order in a zero-pressure fluid in flat cosmological background, which is relevant for the…
We show that the one-loop Euler-Heisenberg QED effective Lagrangian in a constant background field acquires a very different non-perturbative trans-series structure at two-loop and higher-loop order in the fine structure constant. Beyond…
We investigate the field dependence of the gauge couplings of $N=1$ string vacua from the point of view of the low energy effective quantum field theory. We find that field-theoretical considerations severely constrain the form of the…
We investigate two-loop higher-order binding corrections to the fine structure, which contribute to the spin-dependent part of the Lamb shift. Our calculation focuses on the so-called ``two-loop self-energy'' involving two virtual closed…
Following Veltman's approach, we formulate and discuss a general cutting equation for QED in a plane-wave background. We apply the corresponding cutting rules to justify the connection between the two-loop radiative corrections to elastic…
Aiming towards understanding the question of the discrete states in the light-cone gauge in the theory of two-dimensional strings with a linear background charge term, we study the path-integral formulation of the theory. In particular, by…
We study fluctuations around the warped conifold supergravity solution of Klebanov and Tseytlin [hep-th/0002159], known to be dual to a cascading N=1 gauge theory. Although this supergravity background is not asymptotically AdS,…
We compute the two and three loop corrections to the beta function for Yang-Mills theories in the background gauge field method and using the background gauge field as the only source. The calculations are based on the separation of the one…
We calculate the one-loop corrections from inflationary gravitons to the electromagnetic fields of a point charge and a point magnetic dipole on a locally de Sitter space background. Results are obtained both for an observer at rest in…
The 2d gauge theory on the lattice is equivalent to the twisted Eguchi-Kawai model, which we simulated at N ranging from 25 to 515. We observe a clear large N scaling for the 1- and 2-point function of Wilson loops, as well as the 2-point…
Two-loop self-energy corrections to the bound-electron $g$ factor are investigated theoretically to all orders in the nuclear binding strength parameter $Z\alpha$. The separation of divergences is performed by dimensional regularization,…
Scalar QED is studied with higher order derivatives for the scalar field kinetic energy. A local potential is generated for the gauge field due to the covariant derivatives and the vacuum with non-vanishing expectation value for the scalar…
The classical symmetry of the source-free Maxwell equations under electric-magnetic duality rotations leads to a conserved Noether charge, corresponding to the circular polarization of light. We show that, in quantum field theory, the…
We introduce form factors that relate the amplitude of a QED process in vacuum to its corresponding background-field process. The latter is characterised by a reduced S-matrix element where one or more photon field operators are replaced by…
The double copy is by now a well-established relationship between scattering amplitudes and classical solutions in gauge and gravity (field) theories, and is itself inspired by amplitude relations in string theory. In this paper, we…
This is the second of two papers devoted to the proof of conformal invariance of the critical double random current on the square lattice. More precisely, we show convergence of loop ensembles obtained by taking the cluster boundaries in…