19 research outputs found
Regularizing Property of the Maximal Acceleration Principle in Quantum Field Theory
It is shown that the introduction of an upper limit to the proper
acceleration of a particle can smooth the problem of ultraviolet divergencies
in local quantum field theory. For this aim, the classical model of a
relativistic particle with maximal proper acceleration is quantized canonically
by making use of the generalized Hamiltonian formalism developed by Dirac. The
equations for the wave function are treated as the dynamical equations for the
corresponding quantum field. Using the Green's function connected to these wave
equations as propagators in the Feynman integrals leads to an essential
improvement of their convergence properties.Comment: 9 pages, REVTeX, no figures, no table
DFR Perturbative Quantum Field theory on Quantum Space Time, and Wick Reduction
We discuss the perturbative approach a` la Dyson to a quantum field theory
with nonlocal self-interaction :phi*...*phi:, according to Doplicher,
Fredenhagen and Roberts (DFR). In particular, we show that the Wick reduction
of non locally time--ordered products of Wick monomials can be performed as
usual, and we discuss a very simple Dyson diagram.Comment: 15 pages, pdf has active hyperlinks. To appear in the proceedings of
the conference on "Rigorous quantum Field Theory", held at Saclay on July
19-21, 2004, on the occasion of Jacques Bros' 70th birthda
Is There an Observable Limit to Lorentz Invariance at the Compton Wavelength Scale?
The possibility of a frame-induced violation of Lorentz invariance due to
non-inertial spin-1/2 particle motion is explored in detail for muon decay
while in orbit near the event horizon of a microscopic Kerr black hole. It is
explicitly shown that kinematic and curvature contributions to the muon's decay
spectrum--in the absence of any unforeseen processes due to quantum
gravity--lead to its stabilization at the muon's Compton wavelength scale. This
example is emblematic of the search for unambiguous indicators to critically
assess current and future approaches to quantum gravity research.Comment: 9 pages, 1 figure; 2009 Gravity Research Foundation essay competition
submission; accepted for publication in General Relativity and Gravitatio
Spin-gravity coupling and gravity-induced quantum phases
External gravitational fields induce phase factors in the wave functions of
particles. The phases are exact to first order in the background gravitational
field, are manifestly covariant and gauge invariant and provide a useful tool
for the study of spin-gravity coupling and of the optics of particles in
gravitational or inertial fields. We discuss the role that spin-gravity
coupling plays in particular problems.Comment: 18 pages, 1 figur