In this review, we present the key aspects of modern thermal perturbation theory based on the hard thermal loop (HTL) approximation, including its theoretical foundations and applications within quantum electrodynamics (QED) and quantum chromodynamics (QCD) plasmas. To maintain conciseness, we focus on scenarios in thermal equilibrium, examining a variety of physical quantities and settings. Specifically, we explore both bulk thermodynamic properties and real-time observables in high-temperature domains relevant to heavy-ion physics.

中文翻译：

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硬热环——理论与应用


在这篇综述中，我们介绍了基于硬热环（HTL）近似的现代热扰动理论的关键方面，包括其在量子电动力学（QED）和量子色动力学（QCD）等离子体中的理论基础和应用。为了保持简洁性，我们重点关注热平衡场景，检查各种物理量和设置。具体来说，我们探索了与重离子物理相关的高温领域的体热力学性质和实时可观测值。