论文标题
在核环境中用于喷射QCD轻QCD的量子模拟
Quantum Simulation of Light-Front QCD for Jet Quenching in Nuclear Environments
论文作者
论文摘要
我们开发了一个框架，以模拟量子计算机上的核环境中的喷气淬火。该公式基于QCD的轻型汉密尔顿动力学。哈密顿量包括与喷气淬火研究相关的三个部分：动力学，扩散和分裂术语。在动量空间中由$ n $粒子状态组成的基础上，动力学哈密顿量是对角线的。代表扩散和分裂零件的矩阵稀疏。哈密顿量的扩散部分取决于经典的背景量规场，在构建时间演化之前，需要在构造量子电路之前经过经典采样。采样的成本随演化的时间长度和动量网格体积线性缩放。该框架会自动跟踪量子干扰，因此可以在具有两个以上相干分割的情况下研究Landau-Pomeranchuk-Migdal的效果，这超出了最先进的分析范围，无论培养基是静态还是静态，还是静态或膨胀，稀薄或浓密的，也是较薄还是浓，或冷的，也是如此。我们将此框架应用于小晶格上的玩具模型和gluon辐射。在玩具模型和Gluon情况的量子模拟结果中观察到Landau-Pomeranchuk-Migdal效应的本质，这是由抑制总辐射概率的培养基相互作用引起的量子变质。
We develop a framework to simulate jet quenching in nuclear environments on a quantum computer. The formulation is based on the light-front Hamiltonian dynamics of QCD. The Hamiltonian consists of three parts relevant for jet quenching studies: kinetic, diffusion and splitting terms. In the basis made up of $n$-particle states in momentum space, the kinetic Hamiltonian is diagonal. Matrices representing the diffusion and splitting parts are sparse. The diffusion part of the Hamiltonian depends on classical background gauge fields, which need to be sampled classically before constructing quantum circuits for the time evolution. The cost of the sampling scales linearly with the time length of the evolution and the momentum grid volume. The framework automatically keeps track of quantum interference and thus it can be applied to study the Landau-Pomeranchuk-Migdal effect in cases with more than two coherent splittings, which is beyond the scope of state-of-the-art analyses, no matter whether the medium is static or expanding, thin or thick, hot or cold. We apply this framework to study a toy model and gluon in-medium radiation on a small lattice. The essence of the Landau-Pomeranchuk-Migdal effect is observed in the quantum simulation results of both the toy model and the gluon case, which is quantum decoherence caused by medium interactions that suppresses the total radiation probability.
