论文标题
Weyl几何形状中的宇宙粒子创造
Cosmological particle creation in Weyl geometry
论文作者
论文摘要
我们研究了Weyl几何形状中均质和各向同性宇宙学解决方案的可能性，这与Riemannian几何形状不同，通过添加所谓的Weyl载体。 Weyl重力是通过构造引力拉格朗日式在弯曲和形式不变的二次获得的。发现只要存在Weyl Vector与物质字段之间的直接相互作用，可能存在这种解决方案。假设拉格朗日是完美的流体，我们发现如何实现这种互动。由于存在二次曲率项和直接相互作用，因此可以直接从真空中产生完美的流体颗粒，我们发现其生产速率的表达似乎是保形不变的。如果在真空状态下创建宇宙``从一无所有''创建宇宙，我们研究了这个问题，无论该真空是否可以持续存在。结果表明，真空可能在产生非盘状物质（带有正压）方面持续存在，但无法抗拒产生灰尘颗粒。这些粒子是非交互的，可以被视为暗物质的候选者。
We investigated the possibility of the homogeneous and isotropic cosmological solution in Weyl geometry, which differs from the Riemannian geometry by adding the so called Weyl vector. The Weyl gravity is obtained by constructing the gravitational Lagrangian both to be quadratic in curvatures and conformal invariant. It is found that such solution may exist provided there exists the direct interaction between the Weyl vector and the matter fields. Assuming the matter Lagrangian is that of the perfect fluid, we found how such an interaction can be implemented. Due to the existence of quadratic curvature terms and the direct interaction the perfect fluid particles may be created straight from the vacuum, and we found the expression for the rate of their production which appeared to be conformal invariant. In the case of creating the universe ``from nothing'' in the vacuum state, we investigated the problem, whether this vacuum may persist or not. It is shown that the vacuum may persist with respect to producing the non-dust matter (with positive pressure), but cannot resist to producing the dust particles. These particles, being non-interactive, may be considered as the candidates for dark matter.
