We study the quantum evolution of the early universe, its semi-classical analogue together with inflationary regime, in view of a generalized modified theory of gravity. The action is built by supplementing the nonminimally coupled scalar-tensor theory of gravity with scalar curvature squared term and a Gauss-Bonnetdilatonic coupled term. It is generalized, since all the parameters are treated as arbitrary functions of the scalar field. It is interesting to explore the fact that instead of considering additional flow parameters, an effective potential serves the purpose of finding inflationary parameters. The dilaton stabilization issue appears here as a problem with reheating. Addition of a cosmological constant term alleviates the problem, and inflation is effectively driven by the vacuum energy density. Thus Gauss-Bonnet term might play a significant role in describing late-time cosmic evolution.

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从修正的引力理论来看早期宇宙

我们根据广义的修正引力理论研究早期宇宙的量子演化，它的半经典类似物和暴胀机制。该动作是通过用标量曲率平方项和 Gauss-Bonnetdilatonic 耦合项补充引力的非最小耦合标量-张量理论来建立的。它是广义的，因为所有参数都被视为标量场的任意函数。探索这样一个事实很有趣，即不是考虑额外的流动参数，而是一个有效的潜力用于寻找膨胀参数的目的。膨胀子稳定问题在这里表现为再加热问题。添加一个宇宙常数项可以缓解这个问题，并且真空能量密度有效地驱动了膨胀。