electromagnetism=gravity in higher dimensions

[kashiark]

I recently read an article(http://www.newscientist.com/article/mg20327231.900-beyond-space-and-time-5d--into-the-unseen.html) that said that gravity in the fifth dimension could be electromagnetism, but wasn't his math flawed? I seem to recall there being something wrong with this idea.

[javierR]

You're referring to the idea that electromagnetism follows from 5D general relativity when the 5th dimension is compact? Although you would get a four-dimensional gauge field like a photon from this situation, the original scenario is indeed flawed (I wouldn't say the "math was flawed"); but the general idea of having extra dimensions is still plausible. In the end, such models must account for, among other things, the other Standard Model interactions, the discrepancy in coupling strengths of the forces and where/how matter comes into play.