432 citations · 5.7k across the 212 of their papers we have counts for
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New Limits to the Drift of Fundamental Constants from Laboratory Measurements
M. Fischer, N. Kolachevsky, M. Zimmermann +17
We have remeasured the absolute - transition frequency in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a l…
The 2S-2P Lamb Shift in He+
U. D. Jentschura, G. W. F. Drake
The current theoretical status of the Lamb shift in He+ is discussed. Recent calculations of two-loop binding corrections to the Lamb shift significantly shift the theoretical valu…
Renormalization-Group Analysis of the Generalized sine-Gordon Model and of the Coulomb Gas for d >= 3 Dimensions
I. Nandori, U. D. Jentschura, K. Sailer +1
Renormalization-group (RG) flow equations have been derived for the generalized sine-Gordon model (GSGM) and the Coulomb gas (CG) in d >= 3 of dimensions by means of Wegner's and H…
Two-Loop Bethe Logarithms
Krzysztof Pachucki, Ulrich D. Jentschura
We calculate the two-loop Bethe logarithm correction to atomic energy levels in hydrogen-like systems. The two-loop Bethe logarithm is a low-energy quantum electrodynamic (QED) eff…
Physics of Skiing: The Ideal-Carving Equation and Its Applications
U. D. Jentschura, F. Fahrbach
Ideal carving occurs when a snowboarder or skier, equipped with a snowboard or carving skis, describes a perfect carved turn in which the edges of the ski alone, not the ski surfac…
The Study of the Heisenberg-Euler Lagrangian and Some of its Applications
S. R. Valluri, U. D. Jentschura, D. R. Lamm
The Heisenberg-Euler Lagrangian is not only a topic of fundamental interest, but also has a rich variety of diverse applications in astrophysics, nonlinear optics and elementary pa…
Lamb Shift of Laser-Dressed Atomic States
U. D. Jentschura, J. Evers, M. Haas +1
We discuss radiative corrections to an atomic two-level system subject to an intense driving laser field. It is shown that the Lamb shift of the laser-dressed states, which are the…
Two-Loop QED Bound-State Calculations and Squared Decay Rates
Ulrich D. Jentschura, Christoph H. Keitel, Krzysztof Pachucki
We discuss the epsilon-method as used in various recent QED bound-state calculations by considering mathematical model examples. Recently obtained results for higher-order self-ene…
Quantum Electrodynamic Bound-State Calculations and Large-Order Perturbation Theory
Ulrich D. Jentschura
The subjects which are discussed in this Thesis include: the self energy of a bound electron and the spin-dependence of QED corrections in bound systems, convergence acceleration t…
Extrapolation of the Zalpha-Expansion and Two--Loop Bound--State Energy Shifts
Ulrich D. Jentschura
Quantum electrodynamic (QED) effects that shift the binding energies of hydrogenic energy levels have been expressed in terms of a semi-analytic expansion in powers of Zalpha and l…
Radiative energy shifts induced by local potentials
Ulrich D. Jentschura
We study a specific correction to the Bethe logarithm induced by potentials which are proportional to a Dirac-delta function in coordinate space ("local potentials"). Corrections o…
Theory of the Lamb Shift in Hydrogenlike Systems
Ulrich D. Jentschura
Analytic calculations of the Lamb shift represent a considerable challenge due to the size and the complexity of the expressions that occur in intermediate steps. In the current wo…
Asymptotic properties of self-energy coefficients
Ulrich D. Jentschura, Eric-Olivier Le Bigot, Peter J. Mohr +2
We investigate the asymptotic properties of higher-order binding corrections to the one-loop self-energy of excited states in atomic hydrogen. We evaluate the historically problema…
Perturbation Approach to the Self Energy of non-S Hydrogenic States
Eric-Olivier Le Bigot, Ulrich D. Jentschura, Peter J. Mohr +2
We present results on the self-energy correction to the energy levels of hydrogen and hydrogenlike ions. The self energy represents the largest QED correction to the relativistic (…