m-theory - what does the m stand for?

In m-theory, what does the “m” stand for?

Nova just did a series on it. All the experts said that they had no idea what it stood for.

Who came up with the name originally?

Nobody knows for sure what it stands for, but it’s generally believed to stand for ‘membrane’, as it is based around two dimensional objects known as branes.

[Homer] mmmmm … theory [/Homer]

The m can also be a general index, indicating a number of dimensions: A 1-brane is a string, a 2-brane is a surface, and so on. So what do you call a general brane of m dimensions? An m-brane, of course. I’ve also seen p used in this context, but sadly, it doesn’t seem to have caught on.

That, obviously, depends on the audience. :slight_smile:

Ed Whitten was credited with it, according to the same PBS documentary, The Elegant Universe.