http://www.metacafe.com/watch/522542/what_is_quantum_tunneling/
Here is a video thats related
QM tunneling in stars
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Nov 17, 2009
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#2
I watched the first 34 seconds to see if it was anything new. Anything that begins with something along the lines of "you were taught in high school...but...." I have found is bound to be only introducing basics, read over and over again. Some people may find it interesting though I can't imagine this stuff will be included in a semi-advanced paper.
Nov 17, 2009
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#5
There is a brief but very well written discussion of the problem of solar fusion and its solution in 1928-9 in Timothy Ferris' wonderful book "Coming of Age in the Milky Way" -- pp. 260-263.
It turns out, by the way, that while Eddington had calculated a temperature of 40,000,000 K for the interior of the sun, he had no clue at the time what the mechanism might be for fusion to take place. When p+p fusion was examined classically, it turned out that the necessary temperature to overcome the Coulomb barrier classically was on the order of 1000 times the actual temperature - i.e. 10,000,000,000 K.
Even with tunneling (which Gamow had originally studied in connection with alpha decay) solar fusion still appeared to require temperatures on the order of 100,000,000K - an order of magnitude too high.
That's when Atkinson and Houtermans had the final flash of insight -- that the velocity of the atomic particles at the solar core would not be a constant, but would be an average, composed of a few particles going an order of magnitude slower and -- the critical insight -- a few going an order of magnitude faster. Just enough, it turned out, to light the solar fusion candle.
Unfortunately all i have about stellar physics is written in italian, but i can lend an hand if you have specific questions...
Dec 16, 2009
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#7
That "flash of insight" by Atkinson and Houtermans seems remarkably obvious! Why would anyone expect particles in the core of a star to have a fixed speed rather than a broad distribution of speeds similar to that for a gas at normal temperatures?
Dec 16, 2009
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#8
"Finally it slowly dawned on Atkinson and Houtermans, who were rather dim bulbs, that the velocity of the particles in the core of the star would be an average ..."
May be before their idea the mean was taken first on the thermal distribution and then on the cross section with the velocity given by the former (even if it does not make much sense)...
i'm in
I'm not yet doing a degree (in physics and mathematics) but I wouldn't mind reading the paper myself! :-)
)
I have to write a 2000 word essay on a 'high physics context' subject. I chose QM tunneling in stars because I could include a lot of physics from other areas in order to estimate the temperature of the core of a star, and then show that QM tunneling is necessary. So, anything that we can discuss on that front that could spurn some ideas would be great!