标题： 以新的方式描述度量仿射理论：替代框架、示例和解 显示英文标题

标题： Describing metric-affine theories anew: alternative frameworks, examples and solutions

摘要： 在本工作中，我们通过改变场变量，重新描述了度量仿射理论。 一系列等效框架被提出，并进行了详细的识别。 应用新框架的优势在于，任何MAG理论都可以作为带有额外场的黎曼理论来处理。 我们使用新的场变量研究了Hilbert-Palatini作用量，并揭示了场空间中在$SO$变换下的有趣对称性。 然后，我们使用可解且合适的黎曼理论作为可解MAG理论的种子模型，仅限于三个例子。 我们提出了一种具有扭率和非度规性的黑洞解，在某种调节下会获得一个规则核心。 还报告了一种由三形式扭率驱动膨胀的德西特宇宙。 显示英文摘要

摘要： In this work we describe metric-affine theories anew by making a change of field variables. A series of equivalent frameworks is presented and identifications are worked out in detail. The advantage of applying the new frameworks is that any MAG theory can be handled as a Riemannian theory with additional fields. We study the Hilbert-Palatini action using the new field variables and disclose interesting symmetries under $SO$ transformations in field space. Then, we use solvable and suitable Riemannian theories as seed models for solvable MAG theories, restricting ourselves to three examples. We present a black hole solution with torsion and non-metricity which under a certain tuning acquires a regular core. A de Sitter universe with the expansion powered by 3-form torsion, is also reported.