时间的非相干箭与纠缠过去假说。

IF 1.2 3区物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY

Foundations of Physics Pub Date : 2024-07-06 DOI:10.1007/s10701-024-00785-3

Jim Al-Khalili, Eddy Keming Chen

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引用次数: 0

摘要

如果时间的不对称性不是从物理学的基本动力学定律中产生的，那么它就可能出现在特殊的边界条件中。通常的说法是，根据热力学第二定律，过去的热力学熵低于未来的热力学熵，那么追溯到宇宙大爆炸前后的时间，就意味着宇宙一开始一定处于非常低的热力学熵状态：这就是热力学过去假说。在本文中，我们考虑了另一个起类似作用的边界条件，但针对的是非相干的时间箭头，即宇宙子系统在未来比在过去更加混杂。根据我们所说的 "纠缠过去假说"，宇宙的初始量子态具有非常低的纠缠熵。我们澄清了 "纠缠过去假说 "的内容，将其与 "热力学过去假说 "进行了比较，并指出了未来研究的一些挑战和开放性问题。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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The Decoherent Arrow of Time and the Entanglement Past Hypothesis

If an asymmetry in time does not arise from the fundamental dynamical laws of physics, it may be found in special boundary conditions. The argument normally goes that since thermodynamic entropy in the past is lower than in the future according to the Second Law of Thermodynamics, then tracing this back to the time around the Big Bang means the universe must have started off in a state of very low thermodynamic entropy: the Thermodynamic Past Hypothesis. In this paper, we consider another boundary condition that plays a similar role, but for the decoherent arrow of time, i.e. the subsystems of the universe are more mixed in the future than in the past. According to what we call the Entanglement Past Hypothesis, the initial quantum state of the universe had very low entanglement entropy. We clarify the content of the Entanglement Past Hypothesis, compare it with the Thermodynamic Past Hypothesis, and identify some challenges and open questions for future research.

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来源期刊

Foundations of Physics 物理-物理：综合

CiteScore

2.70

自引率

6.70%

发文量

104

审稿时长

6-12 weeks

期刊介绍： The conceptual foundations of physics have been under constant revision from the outset, and remain so today. Discussion of foundational issues has always been a major source of progress in science, on a par with empirical knowledge and mathematics. Examples include the debates on the nature of space and time involving Newton and later Einstein; on the nature of heat and of energy; on irreversibility and probability due to Boltzmann; on the nature of matter and observation measurement during the early days of quantum theory; on the meaning of renormalisation, and many others. Today, insightful reflection on the conceptual structure utilised in our efforts to understand the physical world is of particular value, given the serious unsolved problems that are likely to demand, once again, modifications of the grammar of our scientific description of the physical world. The quantum properties of gravity, the nature of measurement in quantum mechanics, the primary source of irreversibility, the role of information in physics – all these are examples of questions about which science is still confused and whose solution may well demand more than skilled mathematics and new experiments. Foundations of Physics is a privileged forum for discussing such foundational issues, open to physicists, cosmologists, philosophers and mathematicians. It is devoted to the conceptual bases of the fundamental theories of physics and cosmology, to their logical, methodological, and philosophical premises. The journal welcomes papers on issues such as the foundations of special and general relativity, quantum theory, classical and quantum field theory, quantum gravity, unified theories, thermodynamics, statistical mechanics, cosmology, and similar.