Albert Einstein studied this effect and came up with a compelling theory that stated light was both wave and particle.

Despite what you may have heard, diamonds are not forever. Given enough time, your sparkling rock will degrade into common graphite. The carbon atoms that constitute that diamond, however, are forever, or close enough. Stable isotopes of carbon are thought to enjoy lifetimes that extend far longer than the estimated age of the universe

as Hawking notes, Earth was lucky to avoid a cataclysmic collision with an asteroid or comet in the past 70 million years. Other planets could have had their early life-forms wiped out in such a cosmic crash.