A Quantum Theoretical Formulation of Proper Time for Spin 1/2 Particles

Information-theoretical formulation of anyonic entanglement

Anyonic systems are modeled by topologically protected Hilbert spaces which obey complex superselection rules restricting possible operations. These Hilbert spaces cannot be decomposed into tensor products of spatially localized subsystems, whereas the tensor product structure is a foundation of the standard entanglement theory. We formulate bipartite entanglement theory for pure anyonic states and analyze its properties as a non-local resource for quantum information processing. We introduce a new entanglement measure, asymptotic entanglement entropy (AEE), and show that it characterizes dist…

Theoretical formulation of finite-dimensional discrete phase spaces: II. On the uncertainty principle for Schwinger unitary operators

We introduce a self-consistent theoretical framework associated with the Schwinger unitary operators whose basic mathematical rules embrace a new uncertainty principle that generalizes and strengthens the Massar-Spindel inequality. Among other remarkable virtues, this quantum-algebraic approach exhibits a sound connection with the Wiener-Kinchin theorem for signal processing, which permits us to determine an effective tighter bound that not only imposes a new subtle set of restrictions upon the selective process of signals and wavelets bases, but also represents an important complement for pro…

Theoretical formulations on thermodynamics of quantum impurity systems

In this work, we put forward the theoretical foundation toward thermodynamics of quantum impurity systems measurable in experiments. The theoretical developments involve the identifications on two types of thermodynamic entanglement free--energy spectral functions for impurity systems that can be either fermionic or bosonic or combined. Consider further the thermodynamic limit in which the hybrid environments satisfy the Gaussian--Wick's theorem. We then relate the thermodynamic spectral functions to the local quantum impurity systems spectral densities that are often experimentally measurable…

开放量子系统中耗散路径量化的通用框架。I. 理论表述

General Framework for Quantifying Dissipation Pathways in Open Quantum Systems. I. Theoretical Formulation

本文提出基于Nakajima-Zwanzig投影算符技术的通用理论框架，用于量化开放量子系统中各浴自由度的能量耗散路径，并验证其满足能量守恒和细致平衡等热力学原理。

坍缩模型：理论、实验与哲学的回顾

Collapse Models: a theoretical, experimental and philosophical review

本文回顾了坍缩模型实现完整精确表述所需的理论、实验和本体论三个基本条件，指出只有坍缩模型在非相对论量子力学中具有实验后果，并强调澄清其本体论暗示对于理解理论本质、深化表述理解和拓宽解读视野具有重要意义。

A Quantum Model for Coherent Ising Machines: Discrete-time Measurement Feedback Formulation

Recently, the coherent Ising machine (CIM) as a degenerate optical parametric oscillator (DOPO) network has been researched to solve Ising combinatorial optimization problems. We formulate a theoretical model for the CIM with discrete-time measurement feedback processes, and perform numerical simulations for the simplest network, composed of two degenerate optical parametric oscillator pulses with the anti-ferromagnetic mutual coupling. We evaluate the extent to which quantum coherence exists during the optimization process.