The universe is a rich and complex place, but its geometry is astoundingly simple, perhaps forcing us to find the next big revolution in physics thinking.
Our universe is actually really simple, it's just our cosmological theories that are getting needlessly complex, argues one of the world's leading theoretical physicists.
This conclusion may sound counter-intuitive; after all, to fully understand the true complexities of Nature, you need to think bigger, study things on finer and finer scales, add new variables to equations, and think up "new" and "exotic" physics. Eventually we'll discover what dark matter is; eventually we'll gain a grasp of where those gravitational waves are hiding – if only our theoretical models were more advanced and more... complex.
Not so, says Neil Turok, Director of the Perimeter Institute of Theoretical Physics in Ontario, Canada. By Turok's rationale, if anything, the universe, on its largest and smallest scales, is telling us that it is actually amazingly simple. But to fully grasp what this means, we'll need a revolution in physics.
In an interview with Discovery News, Turok pointed out that the biggest discoveries of the last few decades have confirmed the structure of the universe on cosmological and quantum scales.
"On the largest scales, we've mapped the whole sky -- the cosmic microwave background -- and measured the evolution of the universe, the way it's changing, the way it's expanding ... and these discoveries reveal that the universe is astonishingly simple," he said. "In other words you can describe the structure of the universe, its geometry, and the density of matter ... you can essentially describe all that with just one number."
The most fascinating outcome of this reasoning is that to describe the universe's geometry with one number, it is actually simpler than the numerical description of the simplest atom we know -- the hydrogen atom. The hydrogen atom's geometry is described by 3 numbers, which arise from the quantum characteristics of an electron in orbit around a proton.
"It basically tells us that the universe is smooth but it has a small level of fluctuation, which this number describes. And that's it. The universe is the simplest thing we know."
From the largest scales to the smallest scales, the universe seems to be "scale-free" -- in other words, no matter what spatial or energy scale you look at, no scale is "special." And this finding actually suggests the universe has a far simpler nature than current theories suggest.
"Yes, it's a crisis, but it's a crisis of the best kind," said Turok.
So, to explain the origins of the universe and come to terms with some of our universe's most perplexing mysteries such as dark matter and dark energy, we may need to look at our cosmos differently. But this will require a revolution in physics understanding, a revolution possibly as historic as Einstein's realization that space and time are one of the same thing when he formulated his theory of general relativity 100 years ago.
"We need a very different view of basic physics. This is the time for radical, new ideas," he concluded, pointing out that this is a great time in human history for young people to get into the field of theoretical physics, as it will be the next generation that will likely transform the way we view the universe.
