Chasing Einstein

Once we’re out of school, most of us don’t ever stop to think about physics again, and probably also breathe a sigh of relief about that fact. But whether we understand how they work or not, the laws of physics shape our world, and in many cases are more second nature to us than we realize. You might not be able to calculate the coefficient of friction between your car tires and the street, but you know instinctively that said car will brake faster and more efficiently on dry pavement than it will when there’s snow on the road. In the documentary Chasing Einstein, the filmmakers recruit a group of physicists from several nations to discuss one of the biggest mysteries of physics today, a little concept called dark matter.

It’s becoming something of a sci-fi catch phrase, but it’s really a term physicists use for something no one quite understands. Gravity is one of the fundamentals of physics and life. It ranks with death and taxes as something that can be counted on, keeping our feet on the ground and allowing planets to sail smoothly around their respective stars. From the first hominid noticing that leaves never fall up, to Sir Isaac Newton, to Albert Einstein himself, gravity has been one of the most studied phenomena around. Then, thanks to Einstein’s Theory of General Relativity, we realized that gravity as we know it can’t explain some fairly basic things.

For example, there are galaxies rotating contentedly away that shouldn’t be able to stay together based on the gravitational forces of the matter we can see, yet stay together they do and no one can explain it. The phrase dark matter was coined to refer to “Whatever is holding that stuff together when gravity as we know it can’t possibly be holding that stuff together”. The idea is that there’s some new form of matter that can’t be detected with the usual instruments but still has the mass to generate all this extra gravitational pull. Chasing Einstein — and by the way, the Theory of Relativity still hasn’t been toppled after over 100 years and countless leaps forward — is almost as much about following in the great man’s footsteps as it is about the pursuit of the truth of dark matter. That might seem intimidating, but the film doesn’t forget its audience and keeps things simple yet still fascinating.

A dark matter detector.
A dark matter detector. Don’t worry, you don’t need to know how it works.

Some scientists — Dr. Elena Aprile of Columbia University, for one — have spent years of their professional lives in pursuit of proof that dark matter exists. Others, like twin physicists Erik and Herman Verlinde, believe there isn’t necessarily any matter in dark matter, and the real problem is simply that our understanding of gravity is imperfect on a more cosmic scale. Right now either approach might be the correct one, and there’s no telling what the future will bring. All anyone can say for certain right now is that for Einstein’s theory to be correct, there has to be something hidden out there, dark matter or something else, and every physicist out there wants to be the one to solve the enigma.

Featuring other rock stars of science like James Beacham and 2017 Nobel Laureates Kip Thorne and Barry Barish, the film captures a sense of wonder and awe that’s worthy of any science-fiction epic while still staying grounded. It’s our own innate curiosity that drives us to explore the unknown, but it’s physics that propels us forward. The theories can be intimidating, but they also hold the key to all the mysteries of the cosmos — if we can just figure out exactly where and how to look. Chasing Einstein shows us one aspect of the grandest search of all, and does it in an accessible, compelling fashion.