Imagination is an important part of how science works. You may be surprised, you may have thought that science depended on the protean skills of people doing mathematics or chunking through equations. Perhaps for people who don't like math, that can be a little boring. But science is very exciting because creativity and imagination are built-in at the core. That's how we learn about new things and new aspects of the universe that we never anticipated. My favorite example of imagination, is how you can take two disparate things or two disparate pieces of information and combine them to find something new or surprising. In this example from the artist Pablo Picasso early in his career, he combines two routine elements of a rusty old bike. The seat and the handlebars, to make a completely new image of a bull. It's surprising and delightful. The same feeling comes to scientists when they invent a new theory that explains disparate data sets. Another reason imagination is important in science is, it can take us to places that we can't yet venture with our telescopes or our spacecraft or our instruments because we have the power to imagine the impossible or the power to imagine things that could be, but aren't. There's an idea in science called contra-factual. That is things that could be true that don't violate any law of nature or physics, but are not apparently true, they've never yet been observed. Sometimes, we can test our theories or ideas by imagining contra-factuals. Things that we don't actually observe but could be true. That's an interesting hypothetical and imaginary way to do science. In the end, of course, we do need observations to prove or disprove our theories. Continuing our analogies in the arts, here are some examples of impossible things that can be visualized by artists. They look like real physical objects but they cannot actually be constructed. Going along and riding over the top of them, some music written by Conlon Nancarrow early in the 20th century called the X cannon. It involves player pianos altered so they play notes at an impossible speed. This is not physical music. This is not music that any human could play. So it's imagining impossible in music, does this mean we can imagine it in art and in science? Two important examples of imagination and Astronomy involve the imagination of space travel or visualizing space travel hundreds of years before it was possible. Isaac Newton produced a famous diagram which shows a cannon placed on the top of a tall mountain. The cannon is pointing sideways and it fires a cannonball at increasing speeds. As the muzzle velocity increases, the cannonball falls in a parabolic trajectory, explained by his theory of gravity. But Newton realized that if the atmosphere was thin and so not slowing down the cannonball, in other words there was no friction force. If you increase the speed of the cannonball, there would be a speed at which the cannonball was falling at the same rate that the Earth was curving down under it. That's the imagination of an orbit. The speed you get from that calculation in his theory is the orbital speed. We just needed the technology to accelerate any object to that speed which would not happen for over 300 years. But Newton was imagining space travel. Another example that's more relevant recently as we discover exoplanets, is the work of space artists and visionaries going back a hundred or more years who've imagined other worlds in space. The idea of other worlds in space, worlds like the Earth or different from it, far from view maybe even far from telescope analysis goes back hundreds of years. But space artists have increasingly used their talents to visualize worlds and space similar or dissimilar to the Earth, how they might look if we could be there what it might be like to live there or explore there. This space art is helping us in our imagination. It helps propel us into the space exploration that we think will one day take us to these other worlds. Another example from the popular culture involves the imagination of wormholes or white holes. In gravity theory, these are hypothetical situations where space-time is so curve that it doubles back on itself. Essentially, we can have a portal into a completely different region of space or time by stepping through into another world. Here we go. I'm okay, go. Initiate drop sequence on my mark, 10, 9- Now, transmitting. 8, 7- It's released. 6, 5, 4, 3, 2. I'm okay. go. Hello to control. Do you read me? Hello to control. Do you read me? I'm going to try and keep recording. I'm going through some kind of tunnel. There's a light source ahead, brilliant, blue, white. This is already a ship. In movies this has been portrayed several times in several ways including recently, but the idea of a wormhole exists firmly in the theory of gravity. It's just a situation we don't know exists in the real universe though people are in fact looking. The behavior of space-time in situations of intense gravity is a frontier field of research in astrophysics. Imagination is extremely important in science and in particular in astronomy were so few things have been predicted. We use our theories and our observations to bolster our science but we're completely free to imagine situations that haven't yet been observed. Something called the counterfactual, is something that could happen in the universe but has not yet been observed. We can test our theories and our ideas by imagining such things.
