1 post tagged “star”
The subatomic realm is uncertain as to where things are. We cannot know where something is. It follows that we don't know where something has been; nor where it is going. All we can work with are tunnels of probability.
Transcript: http://www.davidcolarusso.com/edblog/?p=33#more-33
This video is an adaptation of an earlier piece of mine--Perspective on quantum mechanical tunneling. That film, however, was designed for a unique audience, and I felt its overall length was limiting its appeal here. So I've repackaged it as one of my weekly postings. I Hope you enjoy.
People have been asking for the math. So here it is. The Sun's core temp is ~13.6 MK. For hydrogen nuclei the Coulomb barrier is roughly 0.1 MeV. This corresponds to a temperature in excess of 1 GK! Luckily, tunneling and the distribution of speeds among nuclei lower the actual temperature required. So without tunneling even the Sun's core isn't hot enough for fusion. To see most of this worked through, check out this link:
http://burro.cwru.edu/Academics/Astr221/StarPhys/coulomb.html
for a less mathematical explanation, try:
http://en.wikipedia.org/wiki/Nuclear_fusion#Requirements
The Tabletop Explainer is a quasi-weekly series answering science questions and presenting brief lessons and ideas for teachers and students. If you have any comments, move the discussion to my blog, "On Education" http://www.davidcolarusso.com/edblog/