Brian Greene

One of the strangest features of string theory is that it requires more than the three spatial dimensions that we see directly in the world around us. That sounds like science fiction, but it is an indisputable outcome of the mathematics of string theory.

The central idea of string theory is quite straightforward. If you examine any piece of matter ever more finely, at first you'll find molecules, atoms, sub-atomic particles. Probe the smaller particles, you'll find something else, a tiny vibrating filament of energy, a little tiny vibrating string.

Startups need to focus on building a foundation for their company culture early, and then they need to revisit it often. Every time a hire is made, a feature is launched, a Facebook status is updated, a press interview is given, a round of financing is raised, or a meeting is held, culture should be part of the decision-making process.

The Internet has become an integral part of everyday life precisely because it has been an open-to-all land of opportunity where entrepreneurs, thinkers and innovators are free to try, fail and then try again.