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View Full Version : alpha - physics???????beyond me



IzmSchism
14th April 2002, 02:50
okay, I was reading the Economist today,

http://www.economist.com/science/displaySt...tory_id=1066862 (http://www.economist.com/science/displayStory.cfm?story_id=1066862)

and one of the articles was on the inconstant constant, to the point the alpha number, which a group of Australian physicists claim to be increasing?? I did not understand a dam thing in this article, I'm a simple social science grad, but I am interested by this possible discovery and what it means, if any one knows please drop me a note,
Cheers!

(Edited by IzmSchism at 2:51 am on April 14, 2002)

antitrot
14th April 2002, 10:44
Oh, you people and your social sciences! j/k ;)

peaccenicked
14th April 2002, 12:11
Theoretical physics sometimes throws up anomolies,
I would not be to bothered by this.
The constant alpha is obtained by using other constants,
it seems to me they have to show what in the other other constants is changeable.
This is highly unusual. The simlest constant to understand is pi. The length of the circumference of a ciricle divided by its diameters length. 3.14........
Plancks constant belongs to quantuum physics
The speed of light is also constant in theory.
Alpa is used in determining the wavelength of light, to my mind.
It is highly unlikely that the change will really affect precision engineering at all or cause much of a stir in astronomy.

honest intellectual
14th April 2002, 18:41
"To get alpha, square the charge of the electron and divide it by the speed of light times Planck's constant, a key value used in quantum theory. Then multiply the result by two times pi"

(1.6 X 10/-19)/2 X (299796304 X 6.63X10/-34) X 2(3.1415926535897)

I make it about 3.197 by 10 to the - 62 (but I think i got the speed of light wrong)

Anyway, if alpha is changing, it means one of the factors is changing (planck's constant, pi, speed of light or the charge of the electron).
Pi cannot change, because space-time has always been the same shape (as far as we know) so all circles have the same diameter:circumference ratio.
Personally, I think it is most likely that the speed of light is changing. It has been be shown that near the beginning of the universe, when the universe was much smaller, the speed of light was greater. Hubble found that the the universe is expanding, so the speed of light should gradually change with it

"The constants that physicists measure in their laboratories are only four-dimensional shadows of more fundamental entities that exist in 11 dimensions. These shadows would shift with time if the hidden dimensions changed scale."
Traditionally, space-time is 4 dimensional, but recent developments in string theory show that on the smallest scale, space time is either 11 dimensional or 26 dimensional.
As the article goes on to say, these extra dimensions are controlled by the laws of M-theory. Which we are only beginning to understand. A change in these dimensions would affect the charge of the electron and thus alpha

libereco
14th April 2002, 21:23
i don't see why any of the other consants would change, so it would probably be light.

Malvinas Argentinas
16th April 2002, 00:34
What is Planck´s constant??

libereco
16th April 2002, 11:33
it's h. about 6.6262 *10^-34 Js

the plank constant times the frequency of a wave is the Energy is carries. h*f = E (or W)

i lack the english terminology, but it's also the steepness or whatever of the graph of frequency and U. (f')


so if you have two lightwaves, and what U is needed to stop the electrons their photons release, then you can calculate h.