There are few people that have brought intense scientific concepts to the masses quite like Professor Brian Cox. Sure, Bill Nye the Science Guy has that tasty nostalgia flavour, but the topics that Brian approaches have ranged from the interesting to the existential, from abnormally slick BBC documentaries to symphonic journeys through the cosmos. And among the various concepts he’s delved into over the years, there’s one that’s near and dear to our oscillating hearts: time.
Time has always been inextricably linked to science and physics in particular. So, when we got a few minutes with IWC’s latest friend of the brand, we decided to ask him the simplest question in the world.
What, exactly, is time?
“There are multiple answers to that. The simplest answer – which sounds bizarre – is that we don’t know. At the most fundamental level in modern physics, we don’t know what it is, and it’s something actively being researched. In my area, black holes, interestingly and for very strange reasons, we’ve come to suspect that space and time are made out of something, that they merge from something deeper that doesn’t have space and time in it. One analogy is that a human being is a collection of atoms. There’s nothing special about those atoms specifically, but in that pattern consciousness emerges. We’ve no idea how, but it does in a remarkable property of nature. It seems that in the same way there is some structure to the universe, from which space and time emerge.”
That all said, while we might not know what spacetime is made of, we have gotten pretty good at measuring it. If you’re wondering how to measure nothing, check out engagement on Twitter. We at least have astronomy to lead the way.
“The concept of the second initially came from astronomy,” explains Brian. “We first kept time from the spin rate of the Earth, but we realised that it’s not very constant – our planet doesn’t make a very good clock. So, then we used the orbit of the Earth around the sun, which is a lot better – but still not good enough. And so, you end up with things like atomic clocks using the frequency of light emitted from atoms.”
Basically, in order to get by in daily life with any degree of accuracy, we’ve had a historical habit of forcing a framework onto natural events, civilising it like some kind of chronometric colonialism. It has however led to a calendar that’s… lets say, less than solidly put together.
“When you look at a calendar, it takes all these things into account. The spin rate of the Earth gives you days and the orbit, years. But there aren’t exactly 365 days in a year; why would there be? The first thing you realise is that spin and orbit have nothing to do with one another, they’re completely independent things, so why would one conform to the other?”
IWC Portugieser Eternal Calendar is accurate for 45 million years
That’s why we end up with the leap year nuances of IWC’s Eternal Calendar, the jank that defines the Gregorian calendar’s odd policy of not having leap years on centennial years, unless divisible by 400. It’s a timescale that we’ve not even sure will even things out perfectly as we’re working on scales of centuries and millennia. And yet it’s a scale that rare secular calendars like the Eternal can take into account. Got it so far? Good. Now for something that’s a little hard to wrap your head around. What exactly is the second hand on your watch actually measuring? Sure, you can flippantly say, ‘a second’, but what does that mean?
As Brian says, “Einstein’s theory of relativity would say that the hand is measuring the distance it’s moving in spacetime, how far it moved between one event and the next over spacetime. So, in that framework, your watch isn’t a timekeeper, it’s a map of the past, present and future.
“There’s no such thing as absolute time in the same way there’s no absolute space. We’ve understood this in physics since Newton – or at least thought about it – but even he had to state that there was absolute space, simply because the notion’s incredibly hard to jettison. We don’t live in a big box in a fixed location at a fixed time and that’s existentially hard to consider.”
The repercussions of this admittedly hard-to-grasp concept is that, in an inverse of Star Wars parsecs, a second is a measure of distance rather than time. But that would be straightforward if that were the only impact the theory has. Throw in the well-known idea what a clock in space runs differently to one on Earth and you open up a whole box of brain spiders.
“The extreme example,” says Brian, “would be relativity and Einstein’s model of spacetime. Imagine events as points on a map. Today, now, is a point on that map. Your watch keeps running and wound until the year 2400, measuring time the entire way, another point. Your watch measures the distance you’ve travelled over the map between those two points. You’ll also have taken the longest possible path between them.
“On the other hand, let’s say you get in a rocket and leave the Earth with your watch on your wrist. You whizz around the Earth quite close to the speed of light and come back in six months, let’s say. You could arrive back in the year 2400 at exactly the same point as the Earth-bound you. Your watch will say only six months has passed as opposed to 375 years. This means that in the latter example you’ve taken a much, much shorter route and therefore that the distance between the past and future is shorter if you’re going faster. That’s the weird geometry of spacetime.”
If that’s hard to wrap your head around, Brian is a master of streamlining concepts: “it’s nothing more complicated than saying the distance between London and Manchester depends on the route, but the distance here is the ‘time’ the watch has measured. That’s what your watch tells you.” In some ways, that’s a nice thought. It means there’s no such thing as wasted time – at least on a physics level – as we keep moving through spacetime. It’s also something that Brian wishes could be incorporated a little more readily into a watch, when we asked what blue sky complication he’d love to see.
“I had this conversation with some engineers at IWC actually. I’d love something that simply measures how long the watch has been working, from its very first moments. That would be the total distance it has moved in spacetime. I thought that would be a beautiful thing.”
This concept of time not being, well, time as we know it, is a bit of a mind blown moment. If something as basic as a second is completely upended, what is anything? And yet, this still isn’t the most existential moment I’ve had with Brian. In the early 2010s, Brian hosted a BBC documentary on the lifespan of the universe. The first part was pretty straightforward and focused on Big Bang, formation of the planets kind of stuff. Then he got onto entropy and the heat death of the universe, the concept that eventually there will be no energy left in the universe and everything will have broken down into its smallest possible component, the inevitability of nothingness.
Entropy is a terrifying concept and one that’s generally agreed as the most likely outcome of the universe. How then, does Brian stay so effervescently up-beat about it all? After all, time isn’t time, it’s merely a pedometer that will eventually read nothing.
“There’s a great quote that I borrow in my book on black holes by David L Goodstein. “Ludwig Boltzmann, who spent much of his life studying statistical mechanics died in 1906 by his own hand. Paul Ehrenfest, carrying on the work, died similarly in 1933. Now it is our turn to study statistical mechanics.”
“But seriously, it’s not all depressing! This is what my show is all about. It’s so incredibly rare and lucky that structures of atoms like us, that can think about and define time, came about, that I believe we should celebrate the fact that we exist at all. We shouldn’t strive for eternity. After all, as Bertrand Russel put it, “I was dead a long time before I was born, and it hasn’t affected me at all.”
But, with that ticking yardstick lingering in the background, doesn’t Brian worry about making the most of his time and ensuring that it’s as well spent as possible?
“It’s so miraculous that we have any time at all that I’d consider every second of it well spent.”
More details at IWC.
