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[Music] High budget, big hair episode of The Last Theory. I flew all the way to Oxford. This beautiful stone building is where I studied physics, way back in the 20th century. Yes, I'm that old.
The 20th century was a truly exciting time. From 1905 to 1973, we made extraordinary progress, probing the mysteries of the universe: special relativity, general relativity, quantum mechanics, the structure of the atom, the structure of the nucleus, enumerating the elementary particles. Then, in 1973, this extraordinary progress stopped. I mean, where are the fundamental discoveries in the last 50 years? He bought a general relativity or quantum mechanics, as Eric Weinstein has claimed on Big Think and reiterated on The Joe Rogan Experience. Elaborations on the Standard Model, but stalled from the theory side since 1973.
The question is, why? Why has there been no progress in physics since 1973? I've come to Oxford to tell you why progress stopped, and why it's set to start again. Why progress in physics might be about to accelerate in the early 21st century, in a way we haven't seen since those heady days of the early 20th century.
How many professional physicists were there at the dawn of the 20th century? A few hundred, a few thousand. There just weren't that many people who were paid by universities to make progress in physics. Again, these few hundred or few thousand physicists did make progress, astonishing progress. How many professional physicists are there today? A few hundred thousand, a few million. There are several orders of magnitude more people paid by universities to make progress in physics today than they were at the dawn of the 20th century.
Something paralyzing happens when a pursuit becomes a profession. When Lord Kelvin, a man of independent means if ever there was one, pursued physics in the 19th century, he wasn't aiming to secure tenure at some prestigious university, and he wasn't worried about helping pay the mortgage on his many talented mansion. There was no money in physics then. Whether we like it or not, Lord Kelvin's wealth allowed him to follow whatever wide-ranging ideas in physics piqued his interest, regardless of whether or not some narrow-minded university don approved.
Now that physics is a profession, however, any physicist with an eye to a secure salary does have to worry about whether a whole host of narrow-minded universities approve. Here's where these academics lecture. I don't know what they like today, but when I was here, I found these lectures awful. And here is where those academics work. I mean, seriously, have you ever seen such an uninspiring place to probe the mysteries of the universe? This is an inspiring building. This is an inspiring building. This is an inspiring building. This. I mean, it's kind of hard to imagine anyone who works here approving a wildly contrarian PhD thesis.
What happens when the younger generation's research has to be approved by the older generation? Well, String Theory. String Theory is what happens. The thing is, physics is hard. It takes serious mental work to wrap your mind around something as difficult as String Theory. You have to mold your mind to be fluent in the mathematical language in which such theories are framed. Once you've molded your mind, it's difficult to unmold it. Even if you're able to unmold your mind, you're not much inclined to. You've made too much of an investment in an accepted way of thinking about the universe to want to start from scratch with an alternative way of thinking about the universe.
Imagine you're a young physicist. You have some wildly comparing ideas, but when you take them to your thesis advisor, who gently guides you to safer ground. If you're not like Lord Kelvin, a matter of independent means, if you're dependent on grants and fellowships and professorships and ultimately tenure, then you follow your thesis advisor's guidance. For now, you toe the line, learning the theories of the older generation, probing some peculiarity in the equations, working around the edges. You imagine that once you're more secure, you'll go back to your wildly contrarian ideas. But you're never quite secure. You do have a mortgage to pay, not on a many-talented mansion, but on a small house on the edge of an extremely expensive university town. And if you do find secure tenure at some prestigious university, well, by then it's too late. You've invested half a lifetime into the older generation's theories. Your mind is molded. Now you're the older generation. You're still interested in holy contrarian ideas, but you know you'll never be fluent in the fundamentally different languages in which such theories might be framed, and certainly not sufficiently fluent to advise a PhD thesis framed in such a foreign language. Whenever a young physicist comes to you with her own wildly contrarian ideas, you gently guide her to safer ground.
I don't know exactly how many professional physicists there were at the dawn of the 20th century, but I do know that Albert Einstein wasn't one of them. When in 1905, he proposed that the passage of time is relative, but the speed of light is absolute, and the energy mass are the same thing, Einstein wasn't being paid by any university to make progress in physics. He wanted to be. He'd been lobbying academics to be considered for a lowly teaching position at whatever university might take him, but he wasn't getting anywhere. So he fell back on making a living as a patent clerk. At the time, he had his most revolutionary ideas, Einstein was an outsider. I don't think he needed to be an outsider. I'm sure he would have had his most revolutionary ideas even if he'd been offered professorships at every university in Europe.
Similarly, I, I don't know exactly how many professional physicists there are today, but I do know that Stephen Wolfram isn't one of them. When in 2020, he laid out a path to a fundamental theory of physics based on the application of rules to hypergraphs, Wolfram wasn't being paid by any university to make progress in physics. He had been in 1980 at Caltech. His PhD thesis in particle physics had been approved, but he then pivoted into computation, founded Wolfram Research, and released Mathematica. All family means an entrepreneur more than an academic. At the time he launched the Wolfram Physics Project, he too was an outsider.
I'm not saying that Wolfram is Einstein. Here's one of the deep differences between them. I don't think Einstein needed to be an outsider to have his most revolutionary ideas. I do think that Wolfram needed to be an outsider to have his most revolutionary ideas in physics. It's no accident that when Wolfram studied physics in this beautiful stone building, he quit without getting his degree. It's no accident that Wolfram has said that when he was here in Oxford, he too found the lectures awful. It's no accident that Wolfram turned away from academia to become an entrepreneur. Through his entrepreneurship, Steve Wolfram has become like Lord Kelvin in his time, a man of independent needs. Whether we like it or not, Wolfram's wealth has allowed him to follow whatever wide-ranging ideas in physics pique his interest, regardless of whether or not some narrow-minded university don approves. He has not invested half a lifetime into String Theory or any of the other theories that have gone nowhere in physics over the last 50 years. His mind has been molded instead by a lifetime of work in computation. They suspect that without this complete freedom from the profession of physics, Stephen Wolfram would never have been able to lay out so completely different a path to a fundamental theory of physics based on computation rather than mathematics.
It may be an exaggeration to say that there has been no progress in physics since 1973, but I do think that physics has become paralyzed in the last 50 years, and I do think that the reason lies among these beautiful stone buildings, and yes, this ugly concrete one. Some celebrated advances in physics have happened here since 1973, such as Roger Penrose's work on black holes, but these advances have been based on the theories of older generations. Penrose's work, for example, was based on Einstein's general theory of relativity. I hesitate to say that a physicist as decorated as Roger Penrose was merely probing some peculiarity in the equations, working around the edges. Still, I can't help but observe that the equations he was probing were written down by Einstein in 1915, way back in the early 20th century.
When physics became a profession, a way to make a living, the incentives for physicists changed. Professions are always vigorously defended by the professionals whose livelihoods depend on it. In the case of physics, it's not just the practice of physics that has been defended, but the theories of physics too, as well as the language of physics. Sure, the trend towards professionalization began long before 1973, but to me, it's no surprise that we've seen the effects compound over the last 50 years, as each generation of physicists has stymied the next with dead-end theories.
I believe that physics might be about to accelerate in the early 21st century in a way we haven't seen since the heady days of the early 20th century. I believe that we'll soon see new theories of physics based on a new language of physics, the language of computation rather than the language of mathematics. And to me, it's no surprise that the most promising development in physics I've seen in my lifetime has come from someone, Stephen Wolfram, who rather than being a professional physicist, is an outsider.
Thanks for listening to The Last Theory. Join me for fresh insights into Wolfram Physics every other week. Subscribe to the free newsletter, podcast, or YouTube channel at lasttheory.com. After all, this might be the most fundamental scientific breakthrough of our time.
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