#### Filter Results:

- Full text PDF available (47)

#### Publication Year

1996

2014

- This year (0)
- Last 5 years (1)
- Last 10 years (20)

#### Publication Type

#### Co-author

#### Journals and Conferences

Learn More

- Holger Gies, Joerg Jaeckel
- 2003

We investigate the possibility of constructing a renormalizable standard model with purely fermionic matter content. The Higgs scalar is replaced by point-like fermionic self-interactions with couplings growing large at the Fermi scale. An analysis of the UV behavior in the point-like approximation reveals a variety of non-Gaußian fixed points for the… (More)

Within the geometric optics approximation, we derive the light cone condition for a class of homogeneous non-trivial QED vacua using the effective action approach. Our result generalizes the “unified formula” suggested by Latorre, Pascual and Tarrach which turns out to be a low-energy limit. We calculate the velocity shifts induced by electromagnetic fields… (More)

- Holger Gies
- 2008

This lecture course is intended to fill the gap between graduate courses on quantum field theory and specialized reviews or forefront-research articles on functional renormalization group approaches to quantum field theory and gauge theories. These lecture notes are meant for advanced students who want to get acquainted with modern renormalization group… (More)

- Holger Gies
- 2003

We analyze the possibility of nonperturbative renormalizability of gauge theories in D.4 dimensions. We develop a scenario, based on Weinberg’s idea of asymptotic safety, that allows for renormalizability in extra dimensions owing to a non-Gaussian ultraviolet stable fixed point. Our scenario predicts a critical dimension Dcr beyond which the UV fixed point… (More)

- Holger Gies, Joerg Jaeckel, Andreas Ringwald
- Physical review letters
- 2006

Possible extensions of the standard model of particle physics suggest the existence of particles with small, unquantized electric charge. Photon-initiated pair production of millicharged fermions in a magnetic field would manifest itself as a vacuum magnetic (VM) dichroism. We show that laser polarization experiments searching for this effect yield, in the… (More)

- Holger Gies
- 2002

The effective average action of Yang-Mills theory is analyzed in the framework of exact renormalization group flow equations. Employing the background-field method and using a cutoff that is adjusted to the spectral flow, the running of the gauge coupling is obtained on all scales. In four dimensions and for the gauge groups SU(2) and SU(3), the coupling… (More)

- Holger Gies, Klaus Klingmüller
- Physical review letters
- 2006

We compute Casimir interaction energies for the sphere-plate and cylinder-plate configuration induced by scalar-field fluctuations with Dirichlet boundary conditions. Based on a high-precision calculation using world-line numerics, we quantitatively determine the validity bounds of the proximity-force approximation (PFA) on which the comparison between all… (More)

We employ the recently developed worldline numerics, which combines string-inspired field theory methods with Monte Carlo techniques, to develop an algorithm for the computation of pair-production rates in scalar QED for inhomogeneous background fields. We test the algorithm with the classic Sauter potential, for which we compute the local production rate… (More)

The derivation of a convergent series representation for the quantum electrodynamic effective action obtained by two of us (is reexamined. We present more details of our original derivation. Moreover, we discuss the relation of the electric-magnetic duality to the integral representation for the effective action, and we consider the application of nonlinear… (More)

- Holger Gies
- 1999

As an application of the QED effective action approach at finite temperature [1]-[5], we investigate the aberration of low-frequency photons from the usual vacuum light cone in the presence of a heat bath. The propagation of photons can deviate from the classically free vacuum behavior when external perturbations exert their influence on the vacuum… (More)