The computer may never be so programmed; but the fact that it could is an essential fact about it, without which it would not qualify as a computer. The counterfactuals that matter to science and physics, so far neglected, are facts about what could or could not be made to happen to physical syst...

Penrose and Hameroff were met with incredulity. Quantum mechanical laws are usually only found to apply at very low temperatures . Quantum computers, for example, currently operate at around

When you change something's direction of travel, you change its velocity - the speed it has in a particular direction. A change in direction always means a change in velocity and acceleration.

Newton's laws of motion state that you can only change the speed of something or...