It's been a while, Science 2.0.

My excuse (if anybody needed one): I've been rather busy over the summer with fieldwork. Not a good excuse, admittedly. But, anyway, I'm back now!

Anyway. There's a rather disparaging quote by Francis Bacon, the 16th century philosopher who basically invented science, who said,

Many secrets of art and nature are thought by the unlearned to be magical.

Quantum physics freaks me out as it is, and Francis Bacon's quote is exactly what jumped to mind when seeing this video. Clearly, it's not magic to some people - people that are more learned than me.

This is a pretty stunning example of what is called the Meissner effect. As some hasty googling has told me (so correct me if I'm wrong) when a superconductor goes below its Critical Temperature, T_c, it won't allow any magnetic field to freely enter it, because of the dipoles induced inside it. This induced field repels the source of an applied field, and will consequently repel the magnet associated with that field.

The cunning bit is that if you place a magnet on top of the superconductor when the superconductor was above its Critical Temperature, and then proceeded to cool it down to below T_c, the superconductor would then exclude the magnetic field of that magnet. So, the magnet itself is repelled, and hey presto - levitation. Not so magical now, then, but still pretty awesome.

I'll leave you with another quote, this time from the author of Saurus, Eden Philpotts. You can imagine this as a direct reply to Francis Bacon.

The universe is full of magical things, patiently waiting for our wits to grow sharper