Friday, April 21, 2006

Mu may have changed over the lifetime of the universe

According to an articne in New Scientist based on a paper in Physical Review Letters, a group is claiming evidence that mu (the ratio of the mass of the proton to the mass of the electron) may have changed over time. Obviously, this would be a significant thing, and this result hasn't been confirmed yet, so it's very early.

Do the astrophysicists around these parts happen to know anything about this or the group that is making the claim?


Blogger Vincent said...

One of the other postdocs at NRAO studies changes in fundamental constants. Usually what happens is that someone gets a 3-sigma result. Then they get better data, beating the error bars down by a factor of two. At the end, they still get a 3-sigma result. It doesn't inspire confidence....

4/21/2006 11:45:00 PM  
Blogger Eric said...

I don't know this group. However, I can comment on the recent rapid growth in the subfield of "using astronomy/cosmology to learn about particle physics". This has become very popular over the last several years. I first noticed about 1999 when supernovae observations supported an accelerating universe and hence the existance of dark energy. Now, it's reached the point where that mentality is showing up in the job market. Now, only time will tell whether this is the emergence of a new interdisciplinary field, the redefining of an old field, or just a passing fad. However, it is clear that at least in the US it becoming very stylish, and hence many more people are working on this kind of thing. When you have many people starting to work on something new, some of them will try new things, make different assumptions, use different techniques, etc., so it wouldn't be suprising to me if there were some early results that turn out to be the product of a lot of enthusiasm.

However, this definitely would be a very big deal, if true. And given the current enthusiasm for the field, I am confident that at least one or two other groups will think of a way to test the claims.

4/23/2006 12:49:00 PM  
Blogger Vincent said...

By the way, have you seen their plot? (I think it's in Phys Rev Lett.) If they didn't include the best-fit lines, would you be able to see the effect they claim in the data?

5/03/2006 11:55:00 PM  

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