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Alex Calogeracos

Publications and source records attributed to Alex Calogeracos.

3 recordsLinked to original sources

The Strong Levinson Theorem for the Dirac Equation

We consider the Dirac equation in one space dimension in the presence of a symmetric potential well. We connect the scattering phase shifts at E=+m and E=-m to the number of states that have left the positive energy continuum or joined the negative energy continuum respectively as the potential is turned on from zero.

quant-ph

A detailed recalculation of the spectrum of radiation emitted during gravitational collapse of a spherically symmetric star

We address the question of radiation emitted from a collapsing star. We consider the simple model of a spherical star consisting of pressure-free dust and we derive the emission spectrum via a systematic asymptotic expansion of the complete Bogolubov amplitude. We present a review of standard features of the problem and we point out certain inconsistencies in previous derivations.

gr-qc

Recalculation of the spectrum of radiation emitted during gravitational collapse

We recalculate the spectrum of radiation emitted from a collapsing star. We consider the simple model of a spherical star consisting of pressure-free dust and we derive the thermal spectrum via a systematic asymptotic expansion of the complete Bogolubov amplitude. Inconsistencies in previous derivations are pointed out.

gr-qc