A Blog for the Curious and the Scientifically Perplexed

This is the story of a great journey that started with a great thought. One day in 1895 a boy looked into a mirror and wondered what the universe would look like if he could travel on a beam of light. That sixteen year old boy was Albert Einstein and that one thought started him on the road to discover his Theory of Relativity. The great man has been reinvented as Albert 2.0 to come back and blog about a journey through space on a beam of light and explain the science behind everything from atoms, blackholes to global warming. If you've just joined and want to start at the beginning use the index on the left. If you're bored try these links below just for fun.


Monday, December 31, 2007

Albert’s lost secret revealed. What is the one thing that can travel faster than light?

The time has come, as the Walrus never said, to think of many things: of light and life and quantum cats, of planets and their rings and why the sun can shine so hot and give imagination wings.

By now Albert and his travelling companion are lost somewhere inside your head which just leaves me to finish off the story. Albert 2.0, like an imaginary friend, is only the palest imitation of the real thing. But then what sequel ever matched the original? I hope having first imagined this journey over a hundred years ago Einstein would have enjoyed finally completing it.

This journey was a thought experiment, the real Albert’s favourite type of experiment. A thought experiment that allowed us to imagine travelling across huge distances of space and time. When we started out 3000 years ago humans didn’t understand much about how things worked. Almost everything humanity knows about light, the universe, life and just about everything else about science was discovered during our travels. From a distant star called Deneb this journey has covered everything from how the sun shines and atom bombs to quantum mechanics and black holes. By ending up being seen we even managed to get inside one of the most the mysterious places in the universe, the human mind.

Different parts of this journey connect in surprising ways. People that made big discoveries in one area often made just as big a discovery in another. Newton worked out gravity and the basics of what light is all about. Kepler worked out planetary movement and was the first to properly explain how the human eye works. Albert himself, famous for his theories of relativity and E=Mc2, received his Nobel prize not for that but for showing that light comes in little packets or photons as they were later named. The total eclipse of the sun that shot Einstein to fame happened at a place and time that was predicted using Newton’s and Kepler’s laws.

Erwin Schrödinger who made the breakthrough in quantum mechanics went onto write a little book in 1944, called ‘What is Life?’ based on three lectures he gave in Trinity College Dublin in early 1943. He predicted that life needed some genetic code in the form of what he called an aperiodic crystal. James Watson read this book and this set him on the path to discover the structure of DNA with Francis Crick in 1953. As Watson himself put it, “Up until then, I was interested in birds. But then I thought, well, if the gene is the essence of life, I want to know more about it. And that was fateful because, otherwise, I would have spent my life studying birds and no one would have heard of me".

The discovery of the structure of DNA relied on a technique that involved using the scattering of X-ray photons to work out the internal shape of crystals. Linking all these discoveries together is light. Light and other forms of electromagnetic radiation, like x-rays and microwaves, crop up in almost every aspect of science from physics to understanding the climate, possibly even in the origin of life itself.

Not bad progress in 3000 years, even if humanity didn’t leave the planet for the first time until 40 years ago. Humans haven’t travelled far in galactic terms but our understanding of what’s going on out there now stretches across the galaxy and the whole universe. In just 500 years since the renaissance, human knowledge and awareness of the universe has spread from one little planet to distant galaxies billions of light years away. So human understanding has travelled far faster than light ever could - the one thing in the universe that breaks Einstein’s rule about nothing going faster than the speed of light, apart from imagination of course.

The big question that no-one can answer is ‘why are all these laws here in the first place?’ Did they just happen by chance? Some of the laws seem so simple and elegant it’s hard to imagine they were just the random results of a huge cosmic accident. To mathematicians and physicists these equations even appear beautiful. The question of how it all started is still unanswered. Did God invent the rules and then just sit back let the universe unfold for the next fifteen billion years? Is it all some huge cosmic experiment by a super advanced race, so powerful they might as well be God? Or are we really inside The Matrix, a huge computer simulation? It’s always worth remembering that despite everything that all the smartest people on Earth do know, there is much more that they don’t know.

With all this progress humans tend to think that all the big discoveries have been made. Does that mean there’s nothing much left to discover nowadays? People thought the same thing a hundred years ago. It wasn’t true then and it almost certainly isn’t now. One of the most successful scientists of the 19th century and one of the contributors to the second law of thermodynamics, Lord Kelvin, proved this point. In 1895 he said that “heavier-than-air flying machines are impossible”, just 8 years before the Wright brothers flew the Kitty Hawk on December 17 1903 - the world’s first heavier-than-air flying machine or aeroplane as they are now called. He also came up with the now famous line in 1900 –

“There is nothing new to be discovered in physics now. All that remains is more and more precise measurement.”

This was just a few years before Einstein’s theory of relativity, quantum mechanics and the discovery of radioactivity completely changed science. So being a world famous scientist doesn’t guarantee you’ll always be right.

The science fiction writer Arthur C Clarke, the man that wrote ‘2001: A Space Odyssey’, invented three laws about progress.

First law: When a distinguished but elderly scientist states that something is possible, he is almost certainly right. When he states that something is impossible, he is very probably wrong.

Second law: The only way of discovering the limits of the possible is to venture a little way past them into the impossible.

Third law: Any sufficiently advanced technology is indistinguishable from magic.

Imagine how the things you take for granted would look like to Lord Kelvin if we could take him on a 100 year journey forward through time. Supersonic aeroplanes, space travel, microwave ovens and computers would all look like some form of magic. What seems like science fiction now could, with the help of the next generation of scientists, be just as real as all these things. Sometime it takes a leap of imagination to start believing that there are things still to be discovered.

So how much more is still to be discovered? Of all the things that seem impossible now, how many will become possible in your lifetime? Maybe someone reading this will go on to prove the impossible really is possible. Remember Einstein was only working in the patent office as a clerk when in a single year he changed the world. May be it could be you that’ll make the next great breakthrough and produce hover cars and space ships that can cover huge distances to finally let humans travel more than a light second into the galaxy. Admittedly there are only a few Albert Einsteins and Isaac Newtons ever born, but for every one of them there are thousands of scientists and inventors who have imagined the impossible and proved it’s possible. Like Alice said, in Through the Looking Glass:

So every second your brain is working flat out to make sense of the pattern of light reaching your eyes. Scanning across this page a jumble of black and white arrives at the retina in the back of your eyes. At the back of your head edges are picked out by individual brain cells. Lines of light and dark put together to make up the letters of the alphabet, the shapes programmed into your brain from nursery school. The letters are effortlessly pieced together into words. Words into sentences and sentences into meaning. The meaning lingers on in your memory, slowly fading over time.

So we will last within you for as long as the memory of this journey remains with you. I hope that some of what you’ve read will stay with you forever and you will try to imagine at least one impossible thing everyday before breakfast. I know we were only a minute fraction of the light reaching your eyes at the moment we arrived. But we can still say we were there, we were seen. Not immortality perhaps, but far better than never being seen at all.

After travelling so far it would have been a dreadful pity to have arrived just as you were blinking.