From MSNBC:
The cosmos would make perfect sense … if it turns out we’re living in a 10- or 11-dimensional realm where gravity is bubbling off a different plane entirely. At least that’s what’s emerging as the hottest concept on the frontier of physics. Though these sound like virtually unverifiable claims, physicists are trying to come up with ways to gather evidence to back up or disprove the extradimensional theories currently in vogue. But it’ll take several years to get that evidence, if it can be gotten at all.
The claim that the cosmos has more than the four dimensions we can perceive — that is, three spatial dimensions plus time — is exotic enough. But the quest to prove that claim brings in a virtual menagerie of mysteries: mini-black holes and dark matter, gravitational waves and cosmic inflation, super-high-energy particle collisions and ultra-powerful gamma-ray bursts.
Even the physicists behind today’s most-talked-about extradimensional theory, Harvard University’s Lisa Randall and Johns Hopkins University’s Raman Sundrum, aren’t yet exactly sure whether the approaches will pay off.
More here.