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Fraser
2005-Apr-18, 06:53 PM
SUMMARY: Researchers from UC Berkeley have looked into the past to confirm that a fundamental aspect of the Universe - the fine structure constant, or alpha - has remain unchanged for at least 7 billion years. This constant shows up in many formulae dealing with electricity and magnetism, and helps describe how radiation is emitted by atoms. This conflicts with a recent announcement from Australian researchers that described a change in alpha over time.

View full article (http://www.universetoday.com/am/publish/light_aspect_unchanged.html)

What do you think about this story? Post your comments below.

Don Alexander
2005-Apr-18, 07:35 PM
The REAL question is: If $\alpha$ is changing, then which fundamental constant that makes up $\alpha$ is changing over time??

After all, it is:

$\alpha=\frac{e}{4\hbar c\pi \varepsilon_0}$

with the fundamental constants e (the charge of the electron), h bar (Planck's constant h divided by 2 pi) and epsilon_0 (the vacuum permittivity constant).

Changing any of these constants seriously screws with the workings of the universe.

David Alexander Kann
PhD Student, Gamma-Ray burst Afterglow Collaboration at ESO
Thueringer Landessternwarte Tautenburg, Germany

antoniseb
2005-Apr-18, 08:13 PM
Originally posted by Don Alexander@Apr 18 2005, 07:35 PM
The REAL question is: If $\alpha$ is changing, then which fundamental constant that makes up $\alpha$ is changing over time?
Hi David,

There is a paper in arXiv today that does a good job of showing that systematic errors and other factors easily explain any observation so far about changing alpha.

Slicksister
2005-Apr-19, 12:53 PM
The article is confused on what an angstom is. There are 10 angstroms per nanometer, not 10 nanometers per angstrom.

madman
2005-Apr-19, 05:02 PM
so when quasars are checked there seems to be a discrepancy in alpha...but with galaxies there is none.

more studies should be done to see if this is always the case...or just a mistake...rather than taking the galaxy result and saying "it's been sorted out".