Professor Jim al-Khalili’s new two-part science series Light and Dark began to be broadcast on Monday on BBC4 – you can still catch it for another two weeks on BBC’s I-Player here.
Khalili began by taking us back to the 3rd century BC when the Greek mathematician Euclid discovered that light travels in straight lines. This was crucially important because it meant that if we could manipulate light and change its path then we could alter the way we look at the world. Khalili took us to Italy where at the beginning of the 1600’s Galileo did precisely that by building a telescope that had an eight times magnification. Galileo was now able to observe far more of our solar system than had ever previously been seen. And in the UK, the scientist Robert Hooke manipulated lenses to look at the world of the very small using one of the first ever microscopes.
Scientists in the coming years would build on these achievements and discover ever more of the universe. There was a very funny bit where Khalili wrote out James Clerk Maxwell’s four famous equations and his subsequent derivation of the “wave equation”. Now this was definitely way above my head and I am pretty sure would have similarly confounded the vast majority of the viewers. However, it was great to see Khalili refusing to dumb this down – it certainly added to my sense of utter awe at Maxwell’s amazing achievement of deriving the speed of light (300,000 Km/second since you ask).
Khalili ended the programme by saying that just when scientists thought that by understanding the properties of light they were coming closer to a fuller understanding of the universe and the Big Bang, the rug appears to have been pulled from under their feet. Starting around thirty years ago, scientists began to suspect that the vast majority of the universe – perhaps 99% of it – is made up of dark matter and dark energy – and we have no idea at present what that really is.
That was a brilliant end to the first part of Light and Dark. A true cliff-hanger if ever there was one. Can’t wait for the second part.
A couple of weeks ago I visited the Royal Observatory in Greenwich and I took a picture of two quotes from our greatest scientific giants, one from Sir Isaac Newton and the other from Albert Einstein. Both quotes sum up for me the wonderful outlook of science and why it has been – and continues to be – so incredibly successful at helping us better understand the world around us.