It's better to read first rate science fiction than second rate science-it's a lot more fun, and no more likely to be wrong.

Science isn't just for scientists - it's not just a training for careers.

I'm a technological optimist in that I do believe that technology will provide solutions that will allow the world in 2050 to support 9 billion people at an acceptable standard of living. But I'm a political pessimist in that I am concerned about whether the science will be appropriately applied.

It's becoming clear that in a sense the cosmos provides the only laboratory where sufficiently extreme conditions are ever achieved to test new ideas on particle physics. The energies in the Big Bang were far higher than we can ever achieve on Earth. So by looking at evidence for the Big Bang, and by studying things like neutron stars, we are in effect learning something about fundamental physics.

Science is a part of culture. Indeed, it is the only truly global culture because protons and proteins are the same all over the world, and it's the one culture we can all share.

I think all countries need to aim to cut the CO2 emissions per person, taking account of externalities like imports and exports.

There may be organic life out there, or maybe machines created by long-dead civilizations, but any signals, even if they are difficult to decode, would tell us that the concepts of logic and physics are not limited to the hardware in human skulls, and will transform our view of the universe.