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arXiv · hep-th/9305116

Valleys in String Foam Suppress Quantum Coherence

John Ellis N. E. Mavromatos·D. V. Nanopoulos
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Abstract

We exhibit string contributions to the $\nd{S}$ matrix relating in- and out- state density matrices that do not factorize as a product of $S$ and $S^\dagger$ matrices. They are associated with valley trajectories between topological defects on the string world sheet, that appear as quantum fluctuations in the space-time foam. Through their ultraviolet cut-off dependences these valleys cause non-Hamiltonian time evolution and suppress off-diagonal entries in the density matrix at large times.

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John Ellis N. E. Mavromatos, D. V. Nanopoulos. 1995-01-25. Valleys in String Foam Suppress Quantum Coherence. https://doi.org/10.1142/s0217732395000466

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