Ignatios Antoniadis

An electron flies out of a tritium nucleus with an energy of 18.57 keV, leaving behind an invisible partner: a neutrino. If that neutrino has access to a fifth dimension, its mass splits into a whole tower of states, and each one takes its own bite out of the spectrum.

In the first instants after birth, the universe might have been multidimensional, like a sheet of paper that suddenly gained thickness. This "thickness"—the extra dimensions — began to inflate rapidly. Such superfast growth is called inflation.

Gravity is a remarkably weak force. A small magnet holds a paperclip against the pull of an entire planet. Physicists have long sought the reason for this weakness, and one guess leads us into hidden dimensions. Perhaps gravity 'leaks' into them, losing strength in our three-dimensional world.