Chern-Simons number asymmetry from CP-violation during tachyonic preheating

We consider the creation of non-zero Chern-Simons number in a model of the early Universe, where the Higgs field experiences a fast quench at the end of inflation. We perform numerical lattice simulations in the Abelian Higgs model in 1+1 dimensions and in the SU(2)-Higgs model in 3+1 dimensions with an added effective CP-violating term. We also comment on the appropriate choice of vacuum initial conditions for classical simulations.Comment: 5 pages, 10 figures, to appear in the proceedings of SEWM2002. Modified presentation of final result. Results unchange

Relations between some analytic representations of one-loop scalar integrals

We compare several parametrized analytic expressions for an arbitrary off-shell one-loop $n$-point function in scalar field theory in $D$-dimensional space-time, and show their equivalence both directly and through path-integral methods.Comment: 12 pages, NIKHEF-H/94-2

W-Particle Distribution in ElectroWeak Tachyonic Pre-Heating

Results are presented of a numerical study of the distribution of W-bosons generated in a tachyonic electroweak pre-heating transitionComment: Contribution to Strong and ElectroWeak Matter 2002, 5 page

Multiloop Calculations in QED by Superparticle Path Integrals

We use the worldline path integral approach to the Bern-Kosower formalism for extending this formalism to the calculation of higher order corrections to N - photon scattering. The case of the two-loop QED beta-function is considered in detail. (Talk given by C. S. at the Workshop QCD 94, Montpellier, France, 7 - 13 July, 1994)Comment: 6 pages, uuencoded postscript-file, HD-THEP-94-3

Three Applications of the String-Inspired Technique to Quantum Electrodynamics

We discuss the following recent applications of the ``string-inspired'' worldline technique to calculations in quantum electrodynamics: i) Photon splitting in a constant magnetic field, ii) The two-loop Euler-Heisenberg Lagrangian, iii) A progress report on a recalculation of the three-loop QED beta -- function.Comment: 10 pages, uuencoded Postscript-File, talk given by C. Schubert at the Zeuthen Workshop on Elementary Particle Theory: QCD and QED in Higher Orders, Rheinsberg, Germany, 21-26 Apr 199

Are CP Violating Effects in the Standard Model Really Tiny?

We derive an effective action of the bosonic sector of the Standard Model by integrating out the fermionic degrees of freedom in the worldline approach. The CP violation due to the complex phase in the CKM matrix gives rise to CP-violating operators in the effective action. We calculate the prefactor of the appropriate next-to-leading order operators and give general estimates of CP violation in the bosonic sector of the Standard Model. In particular, we show that the effective CP violation for weak gauge fields is not suppressed by the Yukawa couplings of the light quarks and is much larger than the bound given by the Jarlskog determinant.Comment: 4 pages. To appear in the proceedings of the 8th Conference on Strong and Electroweak Matter (SEWM08), Amsterdam, the Netherlands, 26-29 August 200

Baryogenesis in the MSSM, nMSSM and NMSSM

We compare electroweak baryogenesis in the MSSM, nMSSM and NMSSM. We comment on the different sources of CP violation, the phase transition and constraints from EDM measurements.Comment: 6 pages, 4 figures. To appear in the proceedings of the 7th Conference on Strong and Electroweak Matter (SEWM06), Brookhaven National Laboratory, May 10-13, 200