Qubit Clock in Quantum Cosmology
We investigate the emergent time scenario in quantum cosmology based on the Page–Wotters approach. Using a quantum cosmological model with a qubit clock, it is demonstrated how the entanglement between the qubit clock and the geometry derives emergence of a time parameter, which defines evolution of...
| Published in: | Universe |
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| Main Author: | |
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2022-02-01
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| Subjects: | |
| Online Access: | https://www.mdpi.com/2218-1997/8/2/99 |
| _version_ | 1851861774044758016 |
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| author | Yasusada Nambu |
| author_facet | Yasusada Nambu |
| author_sort | Yasusada Nambu |
| collection | DOAJ |
| container_title | Universe |
| description | We investigate the emergent time scenario in quantum cosmology based on the Page–Wotters approach. Using a quantum cosmological model with a qubit clock, it is demonstrated how the entanglement between the qubit clock and the geometry derives emergence of a time parameter, which defines evolution of the timeless quantum state of the universe. We show that the universe wave function conditioned by a qubit clock obeys the standard Schrödinger equation and the Fisher information for the clock state, which quantifies entanglement between the universe and the clock, and contributes as a negative energy density. |
| format | Article |
| id | doaj-art-0f0934ce74ed4e9c8eb41efbcb65ebc2 |
| institution | Directory of Open Access Journals |
| issn | 2218-1997 |
| language | English |
| publishDate | 2022-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| spelling | doaj-art-0f0934ce74ed4e9c8eb41efbcb65ebc22025-08-19T22:20:21ZengMDPI AGUniverse2218-19972022-02-01829910.3390/universe8020099Qubit Clock in Quantum CosmologyYasusada Nambu0Department of Physics, Graduate School of Science, Nagoya University, Nagoya 464-8602, JapanWe investigate the emergent time scenario in quantum cosmology based on the Page–Wotters approach. Using a quantum cosmological model with a qubit clock, it is demonstrated how the entanglement between the qubit clock and the geometry derives emergence of a time parameter, which defines evolution of the timeless quantum state of the universe. We show that the universe wave function conditioned by a qubit clock obeys the standard Schrödinger equation and the Fisher information for the clock state, which quantifies entanglement between the universe and the clock, and contributes as a negative energy density.https://www.mdpi.com/2218-1997/8/2/99quantum comologyemergent timequantum clockWheeler-DeWitt equationentanglementFisher information |
| spellingShingle | Yasusada Nambu Qubit Clock in Quantum Cosmology quantum comology emergent time quantum clock Wheeler-DeWitt equation entanglement Fisher information |
| title | Qubit Clock in Quantum Cosmology |
| title_full | Qubit Clock in Quantum Cosmology |
| title_fullStr | Qubit Clock in Quantum Cosmology |
| title_full_unstemmed | Qubit Clock in Quantum Cosmology |
| title_short | Qubit Clock in Quantum Cosmology |
| title_sort | qubit clock in quantum cosmology |
| topic | quantum comology emergent time quantum clock Wheeler-DeWitt equation entanglement Fisher information |
| url | https://www.mdpi.com/2218-1997/8/2/99 |
| work_keys_str_mv | AT yasusadanambu qubitclockinquantumcosmology |