Testing Gravity

The "Physical Applications of Millisecond Pulsars" conference is under way at the Aspen Center for Physics, going through thursday when the X-Games take over.

The meeting started with surveys of current observational and instrumentation projects, in particular the amazing serendipitous discoveries being made by NASA's Fermi γ-ray observatory, in conjunction with ground based radio telescopes, and the new observatories being built.
This was followed by a session on pulsar magnetospheric physics, optical companions to pulsars and other goodies.

Today we get tests of theories of gravity, and pulsars in globular clusters.
Followed this evening by the public talk by Prof. Matthew Bailes at the Wheeler Opera House.

Paulo Freire leads off with a summary of tests of relativity and alternate theories of gravity.
General relativity was famously tested by the Hulse-Taylor pulsar, leading to the Nobel Prize award for Hulse and Taylor.

Since then other pulsars suitable for tests of gravity have been found, including the famous double pulsar J0737-3039 and a number of other binary neutron stars and neutron star-white dwarf binaries suitable for testing gravity.

Bottom line: General Relativity is still good.
In particular scalar-tensor theory variants and TeVeS (an implementation of the MOND phenomenological alternative to dark matter) are being squeezed very tightly in the allowed parameter space, in particular, pulsar tests will soon rule out any TeVeS theory that can also provide a description of dark matter phenomenology.