Friday, July 12, 2013

Medieval astronomy was dominated by the writings of Aristotle.  Aristotle divided motion into earthly lines and heavenly circles, so the planets must surely move about us in perfect circles.  Astronomers soon learned this wasn’t true, but the physics of Aristotle was so deeply rooted in the minds of scholars that astronomers imposed circular motion upon the heavens for a thousand...

Thursday, July 11, 2013

Image credit: Armando Bernui, Braz. J. Phys. vol.35 no.4b, 2006 ...

Image credit: Frank Close, Nature 424, 376-377(24 July 2003). “In any case, the number three fitted perfectly the way quarks occur in nature.” -Murray Gell-Mann ...

 Chess is Almost Solved  Image credit: © 2013 Masterpiecegift.com. “There are some things we do much better than computers, but since most of chess is tactically based they do many things better than humans. And this imbalance remains. I no longer have any issues. It’s a bit like asking an astronomer, does he mind that a...

  Image credit: NASA / ESA. “When I say, ‘I love you,’ it’s not because I want you or because I can’t have you. It has nothing to do with me. I love what you are, what you do, how you try. I’ve seen your kindness...

Hydrogen, Helium, and not much else   Image credit: Frank X. Timmes of http://cococubed.asu.edu/. “I see a lot of new faces. But, you know the old saying, ‘out with the old, in with the nucleus.’”...

Credit: NASA The Sun The majority of stars in the galaxy, including our Sun, Sirius and Alpha Centauri A and B are all main sequence stars. The Sun's relative longevity and stability have provided the conditions necessary for life to evolve here on Earth. Our understanding of the processes involved and characteristics of this key group of stars has progressed in parallel with our...

Imagine you were standing in the center of a circle 100 meters in radius.  How long do you think it would take to leave the circle?  Usain Bolt could do it in 10 seconds, but most people could leave the circle in under a minute.  After all, it’s just a casual 100 meter stroll and you are out of the circle.  But suppose we...