## Articles

In the 1930s Alan Turing discovered a computer program that is logically impossible. What other limits are there to computation?

Are there problems computers will never be able to solve, no matter how powerful they become?

Why a DNA match doesn't necessarily prove your guilt.

Here's the ancient proof that there are infinitely many prime numbers.

Is time real? Are we just puppets living out a future already written? Marina Cortês explains why she thinks time is fundamental and that we don't live in a block universe.

Fundamental physics says time is symmetric - so why does time move forwards for us in a block universe?

Has the future already already been written? Is time just an illusion? Take a step outside of spacetime with cosmologist Marina Cortês to discover the *block universe*.

Marina Cortês is one of a growing number of physicists who believe time is fundamental. We ask her about the alternatives theories to the block universe, where time comes first.