Are there parallel universes? Universes in which, rather than reading this article, you are still asleep; in which you are happier, unhappier, richer, poorer, or even dead? The answer is "possibly". It's a controversial claim but one that has won more and more followers over the last few decades.
The 2012 Nobel Prize for Physics has been awarded to Serge Haroche and David J. Wineland for ground-breaking work in quantum optics. By probing the world at the smallest scales they've shed light on some of the biggest mysteries of physics and paved the way for quantum computers and super accurate clocks.
According to Einstein, the past, present and future have exactly the same character - so why do we feel that there is a particular moment we call "now"? The physicist George Ellis looks for an answer in the curious laws of quantum mechanics.
When it comes to the science of the very small, strange things start happening, and our intuition ceases to be a useful guide. Plus finds out about the crazy quantum world, and spin that a politician would die for.