论文标题
物质与爱因斯坦张量之间的非微小（衍生）耦合的修饰重力和宇宙学
Modified gravity and cosmology with nonminimal (derivative) coupling between matter and the Einstein tensor
论文作者
论文摘要
我们构建了新的修改理论类别，其中物质领域与爱因斯坦张量，即，我们考虑了后者与能量momentum张量的直接耦合，以及其痕迹的衍生物。我们提取不包含高阶导数的通用场方程，并将它们应用于宇宙学框架，获得了弗里德曼方程，这些方程的额外术语会产生有效的黑暗能源部门。在背景层面上，我们表明我们可以通过物质和深色能源时代的顺序成功地描述宇宙的通常热历史，而黑暗能源方程式参数可能位于幻影策略中，目前和未来时期逐渐趋于$ -1 $。此外，我们使用宇宙天文仪数据来面对这一理论，这表明该协议非常好。最后，我们对标量和张量扰动进行了详细的研究，并针对物质过度密度提取近似演化方程，我们表明，预测的行为与观察值一致。
We construct new classes of modified theories in which the matter sector couples with the Einstein tensor, namely we consider direct couplings of the latter to the energy-momentum tensor, and to the derivatives of its trace. We extract the general field equations, which do not contain higher-order derivatives, and we apply them in a cosmological framework, obtaining the Friedmann equations, whose extra terms give rise to an effective dark energy sector. At the background level we show that we can successfully describe the usual thermal history of the universe, with the sequence of matter and dark-energy epochs, while the dark-energy equation-of-state parameter can lie in the phantom regime, tending progressively to $-1$ at present and future times. Furthermore, we confront the theory with Cosmic Chronometer data, showing that the agreement is very good. Finally, we perform a detailed investigation of scalar and tensor perturbations, and extracting an approximate evolution equation for the matter overdensity we show that the predicted behavior is in agreement with observations.
