Quantum theory and Einstein's theory of general relativity are two of the greatest successes in modern physics. Each works ...

Does quantum mechanics allow the future to retroactively influence the past or not? Does quantum mechanics allow the future to retroactively influence the past, as in the infamous delayed choice ...

The ball rolls across the floor because it was kicked, just as Earth orbits the sun because it is tugged by gravity. The connection between cause and effect is fundamental to how we understand the ...