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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
The Definition of Entropy for Quantum Unstable Systems: A View-Point Based on the Properties of Gamow States
Osvaldo Civitarese1, Manuel Gadella2
1Department of Physics, University of La Plata, and IFLP-CONICET, 49 y 115. c.c.67, La Plata 1900, Argentina.
Abstract:
In this paper, we review the concept of entropy in connection with the description of quantum unstable systems. We revise the conventional definition of entropy due to Boltzmann and extend it so as to include the presence of complex-energy states. After introducing a generalized basis of states which includes resonances, and working with amplitudes instead of probabilities, we found an expression for the entropy which exhibits real and imaginary components. We discuss the meaning of the imaginary part of the entropy on the basis of the similarities existing between thermal and time evolutions.
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