Discover Magazine Covers Magnetism in Baloney
Most recent answer: 03/31/2011
- Mike W
What's most peculiar is that Maddox is worked up about magnetism seeming to act at a distance. Yet gravity seems the same way- when you jump, you fall back to the earth even though you aren't contacting the earth during the fall. Didn't he notice? Maddox says he read somewhere that electricity also acts at a distance. Anyone who has ever rubbed a balloon on a sweater can see that without the aid of books.
There is a theory (Maxwell's version from the 1860's is good enough for this purpose) that shows how there really is something (a field) filling the space between the things you directly see, so the electromagnetic forces don't really act a distance. The symptom of this is that it takes a while for the influence to propagate from one place to another- that's how Maxwell calculated the speed of light from the laws of electricity and magnetism.
For all its bluster, Maddox' gripe is really just that the basic descriptions of things turn out to involve math. There's not much we can do about that.
(published on 03/31/2011)
Follow-Up #1: What is gravitomagnetism?
- Paul Miko
Sure, it's called gravitomagnetism and there's a nice Wikipedia article on it. The article doesn't seem to have been updated yet to include the nice confirmation from the Gravity Probe B experiment: .
(published on 10/10/2013)