Enhanced non-macrorealism: Extreme violations of Leggett-Garg inequalities for a system evolving under superposition of unitaries
- URL: http://arxiv.org/abs/2411.02301v1
- Date: Mon, 04 Nov 2024 17:27:05 GMT
- Title: Enhanced non-macrorealism: Extreme violations of Leggett-Garg inequalities for a system evolving under superposition of unitaries
- Authors: Arijit Chatterjee, H. S. Karthik, T. S. Mahesh, A. R. Usha Devi,
- Abstract summary: Quantum theory contravenes classical macrorealism by allowing a system to be in a superposition of two or more physically distinct states.
We show that a system, upon subjecting to transform under superposition of unitary operators, exhibits enhanced non-macrorealistic feature.
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- Abstract: Quantum theory contravenes classical macrorealism by allowing a system to be in a superposition of two or more physically distinct states, producing physical consequences radically different from that of classical physics. We show that a system, upon subjecting to transform under superposition of unitary operators, exhibits enhanced non-macrorealistic feature - as quantified by violation of the Leggett-Garg inequality (LGI) beyond the temporal Tsirelson bound. Moreover, this superposition of unitaries also provides robustness against decoherence by allowing the system to violate LGI and thereby retain its non-macrorealistic behavior for a strikingly longer duration. Using an NMR register, we experimentally demonstrate the superposition of unitaries with the help of an ancillary qubit and verify these theoretical predictions.
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