Indefinite Causal Orders from Superpositions in Time
- URL: http://arxiv.org/abs/2107.08076v2
- Date: Thu, 23 Dec 2021 00:13:01 GMT
- Title: Indefinite Causal Orders from Superpositions in Time
- Authors: David Felce, Nicetu Tibau Vidal, Vlatko Vedral, and Eduardo O. Dias
- Abstract summary: We derive a scheme in which superpositions in time are used to perform operations in an indefinite causal order.
We propose a specific implementation of the scheme and recover the Quantum SWITCH, where quantum operations are performed in an order which is entangled with the state of a control qubit.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Treating the time of an event as a quantum variable, we derive a scheme in
which superpositions in time are used to perform operations in an indefinite
causal order. We use some aspects of a recently developed space-time-symmetric
formalism of events. We propose a specific implementation of the scheme and
recover the Quantum SWITCH, where quantum operations are performed in an order
which is entangled with the state of a control qubit. Our scheme does not rely
on any exotic quantum gravitational effect, but instead on phenomena which are
naturally fuzzy in time, such as the decay of an excited atom.
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