[With quantum computers] you can calculate how many bits are in the universe, how much energy it takes to flip them, how much energy exists, and use that to rule out lots of things about the universe's history. Anything that takes more bit flips couldn't have happened.
Seth LloydFor hundreds of millions of years, Sex was the most efficient method for propagating information of dubious provenance: the origins of all those snippets of junk DNA are lost in the sands of reproductive history. Move aside, Sex: the world-wide Web has usurped your role.
Seth LloydAll physical systems can be thought of as registering and processing information, and how one wishes to define computation will determine your view of what computation consists of.
Seth Lloyd