Quantum superposition of thermodynamic evolutions with opposing time’s arrows
- Author(s)
- Giulia Rubino, Gonzalo Manzano, Caslav Brukner
- Abstract
Microscopic physical laws are time-symmetric, hence, a priori there exists no preferential temporal direction. However, the second law of thermodynamics allows one to associate the “forward” temporal direction to a positive variation of the total entropy produced in a thermodynamic process, and a negative variation with its “time-reversal” counterpart. This definition of a temporal axis is normally considered to apply in both classical and quantum contexts. Yet, quantum physics admits also superpositions between forward and time-reversal processes, whereby the thermodynamic arrow of time becomes quantum-mechanically undefined. In this work, we demonstrate that a definite thermodynamic time’s arrow can be restored by a quantum measurement of entropy production, which effectively projects such superpositions onto the forward (time-reversal) time-direction when large positive (negative) values are measured. Finally, for small values (of the order of plus or minus one), the amplitudes of forward and time-reversal processes can interfere, giving rise to entropy-production distributions featuring a more or less reversible process than either of the two components individually, or any classical mixture thereof.
- Organisation(s)
- Quantum Optics, Quantum Nanophysics and Quantum Information
- External organisation(s)
- Vienna Center for Quantum Science and Technology (VCQ), University of Bristol, University of the Balearic Islands, Österreichische Akademie der Wissenschaften (ÖAW)
- Journal
- Communications Physics
- Volume
- 4
- No. of pages
- 10
- ISSN
- 2399-3650
- DOI
- https://doi.org/10.1038/s42005-021-00759-1
- Publication date
- 11-2021
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103025 Quantum mechanics, 103036 Theoretical physics
- Keywords
- ASJC Scopus subject areas
- Physics and Astronomy(all)
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/quantum-superposition-of-thermodynamic-evolutions-with-opposing-times-arrows(0eabe27f-4c7d-4f6d-9636-7097a2c38fb1).html