Central Charge in Quantum Optics
- URL: http://arxiv.org/abs/2402.17114v2
- Date: Thu, 17 Oct 2024 13:56:07 GMT
- Title: Central Charge in Quantum Optics
- Abstract summary: We show that an expression in terms of a single exponential is possible only at the expense of the introduction of a new element.
A quantum-optical experiment is proposed that brings to light this phenomenon.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: The product of two unitaries can normally be expressed as a single exponential through the famous Baker-Campbell-Hausdorff formula. We present here a counterexample in quantum optics, by showing that an expression in terms of a single exponential is possible only at the expense of the introduction of a new element (a central extension of the algebra), implying that there will be unitaries, generated by a sequence of gates, that cannot be generated by any time-independent quadratic Hamiltonian. A quantum-optical experiment is proposed that brings to light this phenomenon.
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