量子动力学和快速编码的精确宇宙界限
Amit Vikram1, Victor Galitski1
1Joint Quantum Institute and Department of Physics, University of Maryland, College Park, Maryland 20742, USA.
Physical review letters
|February 9, 2024
概括
光谱形状因子为量子动力学提供了普遍的限制,超越了短时间和长时间的现有速度限制. 这一发现对理解量子混沌和多体系统中的信息杂乱产生了影响.
科学领域:
- 量子物理学的量子物理学
- 这是量子混沌.
- 凝聚物质理论 凝聚物质理论
背景情况:
- 量子速度极限,就像曼德尔斯塔姆-塔姆和马戈卢斯-莱维廷极限一样,在短时间范围内限制了量子动态.
- 这些极限是能量-时间不确定性原理的表述.
研究的目的:
- 为了建立一个普遍的,独立于状态的量子力学局限性,适用于任意长时间.
- 为了将此局限于时间依赖或消散系统的概括.
- 在相互作用的多体系统中限制信息乱的速度.
主要方法:
- 使用光谱形状因子,量子混沌中的一个关键量.
- 分析量子系统的实时动态,包括时间依赖和消散系统.
- 调查哈密尔顿系统状态密度的数学属性.
主要成果:
- 光谱形状因子对量子力学设定了比以前已知的速度限制更紧密,更普遍的界限.
- 这一边界适用于在较长时间内完成初始状态的完整集.
- 对于哈密尔顿系统,最快的编程时间与状态密度的里埃变换的非负性有关.
- 在Sachdev-Ye-Kitaev模型中,在大型费米子子系统中的持续混需要指数级长的时间.
结论:
- 光谱形状因子为界定量子动力学和信息杂乱提供了一个强大的,通用的工具.
- 这项研究揭示了量子信息编码速度的基本限制,即使在高度混乱的系统中也是如此.
- 了解这些界限对于开发量子技术和理解复杂的量子现象至关重要.
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