We study the future causally geodesically complete solutions of the spherically
symmetric Einstein-scalar field system. Under the
a priori assumption that the scalar
field
scatters locally in the scale-invariant bounded-variation (BV) norm, we prove that
and
its derivatives decay polynomially. Moreover, we show that the decay rates are sharp.
In particular, we obtain sharp quantitative decay for the class of global solutions with
small BV norms constructed by Christodoulou. As a consequence of our results, for
every future causally geodesically complete solution with sufficiently regular initial
data, we show the dichotomy that either the sharp power law tail holds or that the
spacetime blows up at infinity in the sense that some scale invariant spacetime norms
blow up.
Keywords
Einstein-scalar field system, spherical symmetry,
quantitative decay rate
Department of Pure Mathematics and
Mathematical Statistics
University of Cambridge
Centre for Mathematical Sciences
Wilberforce Road
Cambridge
CB3 0WB
United Kingdom