et: "And here I thought you were from Astronomy. "

Nope, Never claimed that...Though that is the area I am working in now. My degree is in Physics, along the way I got a lot of experience with lasers... turns out that laser work is more lucrative than opening up a physics shop... I have studied astronomy and cosmology a lot formally and informally, but my degree is in physics...

As for your question:

According to the standard model, antiH and H should look the same spectroscopically- spectroscopic measurements have become AMAZINGLY precise and so such measurements on AntiH would be an excellent test of the standard model...

Problem is the only antiH made so far has been travelling at high velocities and short lived- several groups are hoping to make "cold" antiH in the near future- If you are interested in this subject look up papers in phys rev. by Gabrielse, I believe he still is the leader in the field.

In general relativity there is an assumption that H and antiH behave the same in a gravitational field, but that is not absolutely required to be true. This assumption is the "Equivalence principle" . Testing this would either confirm what most already believe or, if there was a difference, shock the heck out of a lot of physicists and open up new science...

It really is a very interesting subject.