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Fraser
2005-Apr-21, 05:09 AM
SUMMARY: There's a number in the Universe which we humans call alpha - or the fine structure constant. It shows up in almost every mathematical formula dealing with magnetism and electricity. The very speed of light depends on it. If the value for alpha was even a little bit different, the Universe as we know it wouldn't exist - you, me and everyone on Earth wouldn't be here. Some physicists have recently reported that the value for alpha has been slowly changing since the Big Bang. Others, including Jeffrey Newman from the Lawrence Berkeley National Laboratory have good evidence that alpha has remained unchanged for at least 7 billion years.

Listen to the interview: Alpha, Still Constant After All These Years (3.3 mb)

Or subscribe to the Podcast: universetoday.com/audio.xml

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

Mr. Smartypants gamer guy
2005-Apr-21, 01:48 PM
i think it cant change it is what makes our universe work and if we would change that well... this would be a difrent universe and things wouldent work the same...

Darrrius
2005-Apr-21, 01:52 PM
Originally posted by Mr. Smartypants gamer guy@Apr 21 2005, 01:48 PM
i think it cant change it is what makes our universe work and if we would change that well... this would be a difrent universe and things wouldent work the same...
I agree, but do you think our Universe could potentially change over countless billions of years?

madman
2005-Apr-22, 12:02 AM
i'll make the same comment again. (nb: i'm not trying to be rude or having a go at anyone)

there appears to be a discrepancy when quasars are checked...but none is seen with galaxies.

more studies should be done on both quasars and galaxies to see if this is always the case..or not.


perhaps also the teams could swap subjects and methods to independantly check the situation?..ie: the aussies could check galaxies using Jeff's method..and vice versa.

StarLab
2005-Apr-24, 10:17 PM
I think, Fraser, that based on the news stories concerning the historical value of alpha, you should create the following poll:

Do you believe alpha has changed over time, or remained constant?

A. The value of Alpha has always remained constant
B. The value of Alpha has always changed over time

GOURDHEAD
2005-Apr-25, 02:09 PM
Do you believe alpha has changed over time, or remained constant?*
A. The value of Alpha has always remained constant.
B. The value of Alpha has always changed over time.* Can voting be germain? If alpha assumed a value commensurate with conditions that allow the evolution of living organisms only a few billion years ago, we may be among the first sentients. Let's hope it does not wander out of bounds before we gain the level of technical competence required to control it.

Nereid
2005-Apr-28, 09:02 AM
Originally posted by madman@Apr 22 2005, 12:02 AM
i'll make the same comment again. (nb: i'm not trying to be rude or having a go at anyone)

there appears to be a discrepancy when quasars are checked...but none is seen with galaxies.

more studies should be done on both quasars and galaxies to see if this is always the case..or not.


perhaps also the teams could swap subjects and methods to independantly check the situation?..ie: the aussies could check galaxies using Jeff's method..and vice versa.
Maybe I'm missing something; didn't Brinchmann et al (http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=APCPCS000736000001000117000001&idtype=cvips&gifs=yes) extend Bahcall's [OIII] emission line work to quasars? Didn't they find alpha to be constant (albeit with rather large error bars)?

madman
2005-Apr-28, 10:20 AM
http://www.universetoday.com/am/publish/un...ot.html?1142005 (http://www.universetoday.com/am/publish/universal_constant_not.html?1142005)

Nereid
2005-Apr-28, 12:00 PM
So the discrepancy is between two (or more?) different methods used to estimate alpha - the many-multiplet (Tzanavaris et al) and the [OIII] emission line pair (Bahcall, Brinchmann et al)?

Both groups have used both &#39;near&#39; (z <1) and &#39;not so near&#39; (z ~2-3) objects.


there appears to be a discrepancy when quasars are checked...but none is seen with galaxieswouldn&#39;t it be more accurate to say "when the LyA forest is compared with quasars"?

madman
2005-Apr-28, 03:29 PM
"So the discrepancy is between two (or more?) different methods"

yes...and

"wouldn&#39;t it be more accurate to say "when the LyA forest is compared with quasars"?"

that&#39;s the odd result that stands out.