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arXiv · 0903.0089

The semilinear Klein-Gordon equation in de Sitter spacetime

Karen Yagdjian
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Abstract

In this article we study the blow-up phenomena for the solutions of the semilinear Klein-Gordon equation $\Box_g ϕ-m^2 ϕ= -|ϕ|^p $ with the small mass $m \le n/2$ in de Sitter space-time with the metric $g$. We prove that for every $p>1$ the large energy solution blows up, while for the small energy solutions we give a borderline $p=p(m,n)$ for the global in time existence. The consideration is based on the representation formulas for the solution of the Cauchy problem and on some generalizations of the Kato's lemma.

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Karen Yagdjian. 2009-02-28. The semilinear Klein-Gordon equation in de Sitter spacetime. https://arxiv.org/abs/0903.0089

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