Having fun with unit fractionsThe number 1 can be written as a sum of unit fractions, that is fractions with 1 in the numerator. But how long can we make such a sum?
Bang, crunch, freeze and the multiverseSome of the things I overheard at Stephen Hawking's 70th birthday conference did make me wonder whether I hadn't got the wrong building and stumbled in on a sci-fi convention. "The state of the multiverse". "The Universe is simple but strange". "The future for intelligent life is potentially infinite". And — excuse me — "the Big Bang was just the decay of our parent vacuum"?!
From planets to universes (part I)This is the first part of the lecture given by Astronomer Royal Martin Rees at Stephen Hawking's birthday symposium.
From planets to universes (part II)This is the second part of the lecture given by Astronomer Royal Martin Rees at Stephen Hawking's birthday symposium.
Free, from top to bottom?A traditional view of science holds that every system — including ourselves — is no more than the sum of its parts. To understand it, all you have to do is take it apart and see what's happening to the smallest constituents. But the mathematician and cosmologist George Ellis disagrees. He believes that complexity can arise from simple components and physical effects can have non-physical causes, opening a door for our free will to make a difference in a physical world.
Freedom and physicsMost of us think that we have the capacity to act freely. Our sense of morality, our legal system, our whole culture is based on the idea that there is such a thing as free will. It's embarrassing then that classical physics seems to tell a different story. And what does quantum theory have to say about free will?
Understanding uncertainty: MicrolivesMany risks we take don't kill us straight away: think of all the lifestyle frailties we get warned about, such as smoking, drinking, eating badly, not exercising and so on. The microlife aims to make all these chronic risks comparable by showing how much life we lose on average when we're exposed to them.
John Conway - discovering free will (part II)In this, the second part of our interview, John Conway explains how the Kochen-Specker Theorem from 1965 not only seemed to explain the EPR Paradox, it also provided the first hint of Conway and Kochen's Free Will Theorem.
John Conway – discovering free will (part I)On August 19, 2004, John Conway was standing with his friend Simon Kochen at the blackboard in Kochen’s office in Princeton. They had been trying to understand a thought experiment involving quantum physics and relativity. What they discovered, and how they described it, created one of the most controversial theorems of their careers: The Free Will Theorem.
John Conway – discovering free will (part III)In this, the third part of our interview, John Conway continues to explain the Free Will Theorem and how it has changed his perception of the Universe.
Outer space: The answer to runnin' in the windRunners and cyclists can tolerate heat and cold but the thing they dislike most is wind. They know it produces slower times. Can we show them why?
