Einstein's Theory of Relativity has held up as long as the examiner does not go too small, then it seems to fall apart. For the ultra-small, it appears we need a separate theory, but that theory has eluded us. And to join the two theories, everyone scrambles to find the holy grail of physics: The Unified Theory. No luck there either. Meanwhile, Einstein's work just keeps working. Einstein and Beyond
"Astronomers have used ESO’s Very Large Telescope, along with radio
telescopes around the world, to find and study a bizarre stellar pair
consisting of the most massive neutron star confirmed so far, orbited by
a white dwarf star. This strange new binary allows tests of Einstein’s
theory of gravity — general relativity — in ways that were not possible
up to now. So far the new observations exactly agree with the
predictions from general relativity and are inconsistent with some
alternative theories. The results will appear in the journal Science on
26 April 2013," John Antoniadis, Max-Planck-Institut für Radioastronomie, Bonn, Germany; Michael Kramer, Max-Planck-Institut für Radioastronomie, Bonn, Germany; Richard Hook, ESO Public Information Officer, Garching bei Munchen, Germany.
Einstein Was Right--So Far: Record Breaking Pulsar Takes Tests of General Relativity Into New Territory