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Entropy decrease in Quantum Zeno Effect

Arun K. Pati
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Abstract

If a measurement process is regarded as an irreversible process, then by Second law of thermodynamics the entropy should increase after any measurement process. By the same spirit a quantum system undergoing repeated measurement should show strong irreversibility leading to entropy production. On the contrary we show that in quantum Zeno effect setting the entropy of a quantum system decreases and goes to zero after a large number of measurements. We discuss the entropy change under continuous measurement model and show that entropy can decrease if we use a more accurate measuring apparatus.

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Arun K. Pati. 2000-06-20. Entropy decrease in Quantum Zeno Effect. https://arxiv.org/abs/quant-ph/0006089

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