Neutrino Masses and Noncyclic Geometric Phase of Entangled Charged Lepton-Neutrino Pair in External Magnetic Field

Neutrino flavor-mass uncertainty relations and an entanglement-assisted determination of the PMNS matrix

As a result of a non-trivial mixing matrix, neutrinos cannot be simultaneously in a flavor and mass eigenstate. We formulate and discuss information entropic relations that quantify the associated quantum uncertainty. We also formulate a protocol to determine the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) matrix from quantum manipulations and measurements on an entangled lepton-neutrino pair. The entangled state features neutrino oscillations in a conditional probability involving measurements on the lepton and the neutrino. They can be switched off by choosing a specific observable on the lepton …

自旋纠缠重子-反重子对的半轻子衰变

Semileptonic decays of spin-entangled baryon-antibaryon pairs

本文推导了自旋极化重子-反重子对半轻子衰变的模块化表示，通过实值矩阵传递自旋信息，便于计算联合微分分布并提取半轻子形状因子。

Dynamics of disentanglement, density matrix and coherence in neutrino oscillations

In charged current weak interaction processes, neutrinos are produced in an entangled state with the charged lepton. This correlated state is disentangled by the measurement of the charged lepton in a detector at the production site. We study the dynamical aspects of disentanglement, propagation and detection, in particular the conditions under which the disentangled state is a coherent superposition of mass eigenstates. The appearance and disappearance far-detection processes are described from the time evolution of this disentangled "collapsed" state. The familiar quantum mechanical interpre…

Charged lepton mixing via heavy sterile neutrinos

Pseudoscalar meson decay leads to an entangled state of charged leptons ($μ,e$) and massive neutrinos. Tracing out the neutrino degrees of freedom leads to a reduced density matrix for the charged leptons whose off-diagonal elements reveal \emph{charged lepton oscillations}. Although these decohere on unobservably small time scales $ \lesssim 10^{-23} s $ they indicate charged lepton \emph{mixing} as a result of common intermediate states. The charged lepton self energy up to one loop features flavor off-diagonal terms responsible for charged lepton mixing: a dominant ``short distance'' contri…

Short baseline neutrino oscillations: when entanglement suppresses coherence

For neutrino oscillations to take place the entangled quantum state of a neutrino and a charged lepton produced via charged current interactions must be disentangled. Implementing a non-perturbative Wigner-Weisskopf method we obtain the correct \emph{entangled} quantum state of neutrinos and charged leptons from the (two-body) decay of a parent particle. The source lifetime and disentanglement length scale lead to a suppression of the oscillation probabilities in short-baseline experiments. The suppression is determined by $π\, L_s/L_{osc}$ where $L_s$ is the \emph{smallest} of the decay lengt…

Entanglement in neutrino oscillations

Flavor oscillations in elementary particle physics are related to multi-mode entanglement of single-particle states. We show that mode entanglement can be expressed in terms of flavor transition probabilities, and therefore that single-particle entangled states acquire a precise operational characterization in the context of particle mixing. We treat in detail the physically relevant cases of two- and three-flavor neutrino oscillations, including the effective measure of CP violation. We discuss experimental schemes for the transfer of the quantum information encoded in single-neutrino states …

Neutrino Oscillations, Entanglement and Coherence: A Quantum Field Theory Study In Real Time

The dynamics of neutrino mixing and oscillations are studied directly in finite real time in a model that effectively describes charged current weak interactions. Finite time corrections to the S-matrix result for the appearance and disappearance probabilities are obtained. It is observed that these effects may be of the same order of the S-matrix result in long-baseline appearance experiments. We argue that fundamentally, the S-matrix is ill-suited to describe long-baseline events due to the fact that the neutrino is produced in an entangled state with the charged lepton, which can be disenta…

Running CP-violating Phases of Majorana Neutrinos

Three CP-violating phases of the $3\times 3$ lepton flavor mixing matrix $V$, denoted as $δ$, $ρ$ and $σ$ in a useful phase convention, are entangled with one another in the one-loop renormalization-group equations. We show that $δ=90^\circ$ at the electroweak scale ($Λ_{\rm EW} \sim 10^{2}$ GeV) can be radiatively generated from $δ=0^\circ$ at the seesaw scale ($Λ_{\rm SS} \sim 10^{14}$ GeV) in the minimal supersymmetric standard model, provided three neutrino masses are nearly degenerate. As for the Majorana phases $ρ$ and $σ$, it is also possible to radiatively generate $ρ=90^\circ$ or $σ= …

长寿命中微子质量媒介子的味层析：在高亮度大型强子对撞机（HL-LHC）上探测中微子质量序

Flavor Tomography of Long-Lived Neutrino-Mass Mediators: Probing the Neutrino Mass Ordering at the HL-LHC

该研究提出在HL-LHC通过长寿命带电粒子的延迟轻子信号，利用共享耦合条件确定的味比区分中微子质量序，约25个事例即可实现3σ区分，且不依赖CP相位δ_CP。

统一理论中由轻夸克介导的双圈中微子质量

Leptoquark-Mediated Two-Loop Neutrino Mass in Unified Theory

本研究提出基于SU(5)规范群的统一理论，通过标量轻夸克双圈产生中微子质量，该模型可实现规范耦合统一，预言TeV量级新物理态及可观测轻子味破坏速率，兼具简洁性与预测能力。

Neutrino mixing and oscillations in quantum field theory: a comprehensive introduction

We review some of the main results of the quantum field theoretical approach to neutrino mixing and oscillations. We show that the quantum field theoretical framework, where flavor vacuum is defined, permits to give a precise definition of flavor states as eigenstates of (non-conserved) lepton charges. We obtain the exact oscillation formula which in the relativistic limit reproduces the Pontecorvo oscillation formula and illustrate some of the contradictions arising in the quantum mechanics approximation. We show that the gauge theory structure underlies the neutrino mixing phenomenon and tha…

强电磁场中类轴子粒子衰变成电子 - 正电子对的自旋分辨衰变

Spin-Resolved Decay of Axion-Like Particles into Electron--Positron Pairs in Strong Electromagnetic Fields

研究强激光场中类轴子粒子衰变成电子 - 正电子对的自旋分辨衰变，用Baier - Katkov形式和局部恒定场近似推导解析速率，揭示有限质量、阈值效应与自旋分辨光谱、纠缠的关系，为强场ALP搜索提供特征标识。