Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Preheating of the nonminimally coupled inflaton field   We investigate preheating of an inflaton field $\phi$ coupled nonminimally to
a spacetime curvature. In the case of a self-coupling inflaton potential
$V(\phi)=\lambda \phi^4/4$, the dynamics of preheating changes by the effect of
the negative $\xi$. We find that the nonminimal coupling works in two ways.
  First, since the initial value of inflaton field for reheating becomes
smaller with the increase of $|\xi|$, the evolution of the inflaton quanta is
delayed for fixed $\lambda$. Second, the oscillation of the inflaton field is
modified and the nonadiabatic change around $\phi=0$ occurs significantly. That
makes the resonant band of the fluctuation field wider. Especially for strong
coupling regimes $|\xi| \gg 1$, the growth of the inflaton flutuation is
dominated by the resonance due to the nonminimal coupling, which leads to the
significant enhancement of low momentum modes. Although the final variance of
the inflaton fluctuation does notchange significantly compared with the
minimally coupled case, we have found that the energy transfer from the
homogeneous inflaton to created particles efficiently occurs for $\xi<-60$.

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The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
10
The categories of this paper are: q-bio
36
The categories of this paper are: cmp-lg