  We study a four-dimensional spacetime induced by the recoil of a
D(irichlet)-particle, embeded in it, due to scattering by a moving string. The
induced spacetime has curvature only up to a radius that depends on the energy
of the incident string. Outside that region (`bubble') the spacetime is matched
with the Minkowski spacetime. The interior of the bubble is consistent with the
effective field theory obtained from strings, with non-trivial tachyon-like and
antisymmetric tensor fields (in four dimensions the latter gives rise to an
axion pseudoscalar field). The tachyonic mode, however, does not represent the
standard flat-spacetime string tachyon, but merely expresses the instability of
the distorted spacetime. Due to the non-trivial matter content of the interior
of the bubble, there is entropy production, which expresses the fact that
information is carried away by the recoil degrees of freedom. We also
demonstrate that a particle can be captured by the bubble, depending on the
particle's impact parameter. This will result in information loss for an
external asymptotic observer, corresponding to production of entropy
propotional to the area of the bubble. For the validity of our approach it is
essential that the string length is a few orders of magnitude larger than the
Planck length, which is a typical situation encountered in many D-brane-world
models. A very interesting feature of our model is the emission of high-energy
photons from the unstable bubble, which might be related to the observed
apparent ``violations'' of the GZK cutoff.
