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Ludger Hannibal

Publications and source records attributed to Ludger Hannibal.

7 recordsLinked to original sources

Response of massive bodies to gravitational waves

The response of a massive body to gravitational waves is described on the microscopic level. The results shed a new light on the commonly used oscillator model. It is shown that apart from the non-resonant tidal motion the energy transfer from a gravitational wave to an electromagnetically coupled body is in general restricted to the surface, whereas gravitational coupling gives rise to bulk excitation of quadrupole modes, but several orders of magnitude smaller. These results do not contradict standard theory, rather present a different viewpoint. A microscopic detector making use of the effect is suggested.

gr-qc

Geometric Foundation of Spin and Isospin

Various theories of spinning particles are interpreted as realizing elements of an underlying geometric theory. Classical particles are described by trajectories on the Poincare group. Upon quantization an eleven-dimensional Kaluza-Klein type theory is obtained which incorporates spin and isospin in a local SL(2,C) x U(1) x SU(2) theory with broken U(1)x SU(2) part.

quant-ph

On Hegerfeldt's paradox

The acausal behavior of relativistic states exhibited by Hegerfeldt is shown not to be present in physical systems described by first order in time evolution equations.

quant-ph

Dirac Theory in Space-Time without Torsion

It is proven that the usual quadratic general-covariant Lagrangian for the Dirac field leads to a symmetric, divergence-free energy-momentum tensor in the standard Riemannian framework of space-time without torsion, provided the tetrad field components are the only quantities related to gravitation that are varied independently.

gr-qc