So what is the energy power density of fusion?

Well, it's about 10 million times higher than gasoline.

Wow.

Yes.

So I point this out to people all the time, how extraordinary gasoline is, 'cause you have a gallon of this stuff, you get in your 2-ton car, and that gallon can propel that 2-ton car nowadays 30, 40 miles at high speed, right?

So that's an energy density.

It's already an extraordinary— in fact, I just drove here, I drove 80 miles here, no problem.

whatsoever, right?

It's actually— it's interesting.

It's like, this is— these numbers matter, by the way.

It has about 60 times the energy density, which again is the energy you can extract per weight, right?

So say it once again.

How many times?

About 10 million.

Wow.

Right.

Dennis Whyte, welcome to Particles of Thought.

Thanks for having me.

It's a pleasure.

Yeah, so you are a professor of nuclear science and engineering at MIT?

That's correct.

Ah, sort of an overachiever there.

Well, listen, man, you are at the cutting edge of fusion research.

And before we get started, I would love it if you would describe for our audience, you know, the quick version of what is fusion?

So fusion is the process that it sounds like, is that you take two fundamental particles, nuclei, and you fuse them together.

And then they change their identity.

Hmm.

So it turns into a new nucleus, which means it turns into a new element.

So if you remember the periodic table, right?

And fusion fuses light particles into heavier particles.

And so there's an incredible array of reactions that actually do fusion.

In fact, what people, most people don't realize, a fun starting fact, is that the more interesting atoms in your body and in the planet Earth were created by fusion.

We call it nucleosynthesis, which just means the creation of nuclei.

And the heavy ones were created by supernovae a long time back in the history of the universe.

But for our practical purposes, what we're interested in is fusion energy, which is the source of energy of stars and our own sun, which is the fusion of the lightest element, hydrogen—Yes.

—into helium.

Again, this is simplifying it, but basically by that rearrangement, it releases staggering amounts of energy.

And it's basically the engine of the universe.

I love that.

Fusion is the engine of the universe.

Yes.

So there have been many breakthroughs, and the challenge has always been to make it viable as energy for humanity, right?

Yes.

And the sort of the calling card of fusion energy is that it's gonna be really clean in comparison to other fossil fuels and nuclear processes that depend on fission, as well as less expensive.

Is that still accurate?

The first part is totally accurate.

The second part is TBD.

TBD.

Yeah, because as we, I mean, you're right, there have been extraordinary advances in fusion, But what's also, so we're starting to get over what seemed like very difficult scientific issues with respect to establishing the conditions that are like in the center of stars.

Yes, that is difficult, right?

Yeah, yeah.

And there's a wide variety, which we can discuss, there's a wide variety of approaches which has now been successful at that, right?

So now we're starting to get greater clarity on what integrated engineering systems that would look like to actually make an energy product.

And of course, to do that, then that starts to gain clarity as to the cost of it.

I see.

Right.

And so there's a common misconception of fusion is that because the fuel is free, effectively free, is that it'll be a free energy source.

This also just tells you how different of an energy source fusion is.

It's actually, it's not the cost and the accessibility to it is not driven by access to the fuel, but to the technology and the manufacturing capability of building the objects that would actually deliver fusion.

So guess what?

We need a new discipline to tell us about what that's going to cost as a practical energy source, which we are starting to do now as well.

You know, that's one of my favorite parts of being a scientist is that so often you're trying to do something and you can't get all the way there because something you need for an intermediate step has not yet been invented.

Yeah.

Yes.

So you have to invent it in order to get to where you're trying to go.

So in comparison to say other renewables, so when you talk about the fuel is free, right?

So wind, the fuel is free, right?

Solar, the fuel is free, but then you also have geothermal energy.

So how does fusion compare to these other known renewables as well as fossil fuels?

Right.

So its distinguishing feature, it has several distinguishing features, fusion energy.

So one of them is energy intensity or power density.

And what does that mean?

It's the amount of energy that you can extract from, and this is the easy way to think of it, from a single atom.

Yeah.

Or probably even easier to think of, from a mass of fuel.

So if you take a pound or a kilogram, we're scientists, so we use metric.

If you take a kilogram of any particular fuel and you say, okay, I'm going to do something to it and now extract energy.

So let's take, you take a kilogram of coal, or you take a kilogram of gasoline, and then you do it with some process.

So what is the energy power density of fusion?

Well, it's about 10 million times higher than gasoline.

Wow.

Yes.

'Cause, so I point this out to people all the time, extraordinary gasoline is, 'cause you have a gallon of this stuff, you get in your 2-ton car, and that gallon can propel that 2-ton car nowadays 30, 40 miles at high speed, right?

So that's an energy density.

It's already an extraordinary— in fact, I just drove here, I drove 80 miles here, no problem whatsoever, right?

It's actually, it's interesting, it's like, these numbers matter, by the way.

It has about 60 times the energy density, which again is the energy you can extract per weight, than a lithium battery.

Oh, and if you buy an electric car, you go, "how come the battery is so big compared to the old gas tank?"

Well, there you go.

So the gas tank has a higher energy density, so you need a smaller gas tank than lithium battery.

Exactly.

So to get the same amount of energy, you need a bigger volume or a bigger mass of it, right?

So this is where fusion, of like, wow, right?

So say it once again, how many times?

About 10 million.

Wow.

Right.

So you think of a factor of 50 is big, 10 million.

So I think of fusion as like the, the last step before the Holy Grail.

And the Holy Grail is likely never going to occur, perhaps, and that's what Star Trek uses, right?

Matter-antimatter fusion chamber, where you get 100% of the mass converted into energy versus like a tiny amount, but still.

Oh, so actually, since we used factors like that, so fusion is the only thing that comes close even to matter-antimatter.

So it's about 1% actually.

Oh, so it's a factor of 10 million from gasoline, but only a factor of 100 away.

Wow, that is super interesting.

And matter-antimatter is, is crazy actually, which is that all of the energy that's captured in the mass is converted into kinetic energy, which is what you would use as an energy source.

That is nuts.

It is nuts.

I didn't realize it was that close.

Yes.

Wow.

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So I hear you've added a new title to your resume and your curriculum vitae.

Yes.

Can you tell us about that?

Yeah, so I'm going to, in the fall, I'm going to take on the role of Chief Executive Officer of the United Kingdom's Atomic Energy Authority.

Oh, that is very impressive.

Tell us about that organization.

Right.

So that organization is tasked— it's the lead organization, it is the government organization in the United Kingdom to commercialize fusion.

So to lead the— and that entails all the different aspects of it, the science, the technology, and the eventual commercialization and economic viability of fusion.

So it's a great privilege and honor to take that on.

It's really— taking on what is in fact an emerging theme in fusion, which is because fusion has enough viability now, nation-states are starting to make very big plays towards the understanding that this could be a revolutionary new energy source for not for just their country, but then the economic impact that that would have for them.

One of the things that was really enlightening to me, I saw last year, is a plot of energy use by society versus, or energy production, I forget which one, versus their GDP or some economic measure.

It's usually, they often use the human, the UN Human Development Index.

Oh, is that what it is?

Yeah, yeah, yeah.

Okay, yeah, yeah, yeah.

And it's like a direct correlation?

It's a direct correlation.

We've known this for, well, ever since the Industrial Revolution started.

We basically understood that energy use is directly correlated to economic well-being.

Well, again, I mean, just think through that.

Oh, of course.

Of everything that you did today that used energy.

Right.

Yeah.

Like, oh, you woke up.

You charged your phone.

You plugged in your kettle.

You made a hot breakfast.

You ate, which required energy to be expended to get that food.

For food, to grow the food and get it to you.

And then you took— you commuted to work.

And you did those things, these lights, this whole studio, everything, everything, everything uses energy.

So, you know, by all measures, you know, I'm a researcher as well, right?

You know, there are certain places you want to make it to.

You have the greatest resources, you have the greatest minds, you know, everybody wants to come work with you, and you're leaving such a great position where you've also started a company here to go here.

So is the UK the place to be for fusion right now?

Are they, because when I think about— we talk about oil and gas a lot, but when we talk about the cutting edge, my mind immediately goes to United States, China, European Union.

And when I think Europe, I think ITER or ITER, however you pronounce it, right?

So why the UK?

Right.

So why the— it's a great question.

Why the UK?

So this comes about, it's actually, it's really a reflection on what has changed in fusion.

On what timescale?

Well, in the last five years.

Okay.

And a lot of it stemming from, not ironically, from the creation of Commonwealth Fusion Systems out of MIT.

Yeah.

Right, right, right, right, right.

Which was really, what it did was, you know, started in my class at MIT, which was the realization that a new class of technology, new superconducting materials, would have a chance to actually significantly reduce the cost and the size of fusion devices and therefore allow a company to launch actually as a viable incubator basically of a new fusion industry.

Not a nation.

Right, yeah, not a nation, a company, right?

In fact, it was six of us in a room at MIT basically came up with a plan around ten years ago.

So amazing fusion— Wait a minute, wait a minute, wait a minute.

six years ago I was a visiting professor at MIT.

There should have been seven of us in that room.

They didn't send me the memo.

Oh my God.

That was a loss, yeah.

Oh my God, I'm gonna talk to the president of the Galactic Empire.

Yeah, yeah, that's a good idea.

So what has that meant?

So what it has meant is that there's a new era in fusion in front of us.

They're building, we'll talk about it later in detail, they're building a prototype right now just outside of Boston.

But it also tells us what we're not ready, so ready for, which is that namely the, what we have a lot of confidence in now is that we are going to make the science achievement of in fact having, making large, all those things that I promised before, energy density, how you make net energy out of it that becomes a practical energy source.

So let's back that up a little bit because my understanding, I think, 'cause with devices like what we mentioned earlier, DPF, there have been devices that could do fusion, including bombs, but there wasn't more energy out than you put in in a controlled way ever until very recently.

That's right, including the experiment we ran at MIT, including the experiment that was in the UK at the lab that I'll be leading.

And in those, very impressive, right?

And in fact, in the experiment, just to put it into context, in the experiment that was at the UKAEA, produced world records for the amounts of energy that was made out of fusion.

So it was producing approximately 10 million watts.

Again, we'll use that number.

That's a very impressive amount, right?

Right.

And it sustained that for like five or six seconds.

However, at that point, it was approximately that there was about double that amount of power going into the fuel to keep it hot, to keep the fusion reaction.

So I said, okay, so that's an incredible accomplishment, but it is not what the— is not sufficient for being able to do it for an energy source.

Right.

So that's actually what Commonwealth Fusion Systems is doing right now, using this new superconducting magnet technology that was not available when those old experiments, including ITER, was actually designed.

That actually now has the prospect to actually make about ten times the amount of— so ten times the fusion energy as the energy that you put into the fuel to get it hot.

And it's like, aha, now we're cooking, right?

Good pun.

Right, so, but to go back to like why this changed then, because then, like most new technology sectors, it's not just one revolution that occurs.

It's actually a stacked set of accomplishments that then get you to an actual energy product or a product of some kind that you can start selling and get out into the marketplace.

In fact, they told us to turn these off.

But if you go back and look at the history of this thing, is that that's not one invention.

It's actually a stacked set of inventions— It is.

Which basically allowed this technology to finally integrate into a product that then obviously changed the way that we deal with data and communicate with each other.

Fusion will be no different on this.

And so the next set of challenges are really— you can basically break down fusion into two, two, three difficult things.

We'll just talk about the first two.

One, you have to make this fuel very hot and make net energy, which is almost all that we've concentrated on because it has to get very hot, hotter than the center of the sun.

Yeah.

Yeah, it's like, oh yeah, that's going to be hard.

It has been hard, right?

But, you know, we can see that like right on the horizon, right, on that part.

But the second part of it is you must extract this energy.

And the energy that really is released from fusion is in a very peculiar or particular form, right?

It's very, very, very energetic particles because of that large energy density that I talked about.

Yeah, yeah.

And it's in a very special environment.

So now what you have to do is develop all of those integrated technologies that will actually make— extract the energy, put it into a sellable and usable form, say electricity or fuels, and be able to construct those, diagnose them, like measure them, maintain them.

And that's actually where the UK has made a significant investment is in those.

Because right now on the ground, they are building three major new capabilities in the fusion space.

And along with a commitment from the UK government to not only do those as technical developments, but to commercialize them.

So it's really an evolution.

It's a mirror of the evolution that fusion itself is taking.

So is this the case that by being an early investor, they're going to be the leader for the future?

That's their proposal.

And that's actually why they've garnered such significant support, actually, from their government towards that.

Because in the end, there's going to be— when you look at a fusion industry, which is the thing that we actually want in the end, like a worldwide fusion industry, there will be multiple components of this.

Again, it's like— I like to use modern airplanes.

So everybody thinks of Boeing or Airbus, right?

Who are essentially vertical integrators because they take the concept.

They sort of— here's what the general feature of the plane is going to be.

Here's the customer base.

They take care of that part.

But do you know how many vendors there are that actually go into a commercial airplane?

I mean, it's staggering, right?

So think about, oh, then there's Pratt & Whitney or Rolls-Royce, which make the engines.

But there's even the things that make the screens that go in front of you in the seat or other things.

And you know what I just discovered a week ago?

Is that most airlines don't even own their planes.

They lease them.

They lease them.

Yeah, yeah, yeah, yeah, yeah.

And then there's other aspects which are specialized economics.

Exactly.

So within this, that is the prospect that's in front of everybody now.

It's like, how do you make the best— because what always slows down or stops tech innovation is two things.

It's going to be— it's like, the two bottlenecks are always money, resources, and talent.

Right.

And so investment, large-scale public programs, partnerships around these things, they are all mechanisms about how do you find the most effective, time-effective, and resource-effective way to get to that end goal.

Well, let me ask you this.

So I was in a semiconductor field 30 years ago or so, 25 years ago.

Well, yeah.

And there's an organization called SEMICON where there are problems that all of the semiconductor companies are facing.

And so they say, okay, let's pull together and solve this.

I'm so glad you asked me about that because I use this analogy or that historic example all the time.

So here you are in the competitive landscape, like brutally competitive between the different ones.

Good, because we love the competitive market because it brings out great products.

Yeah.

We get great, you know, great benefit to our economy.

But then you also realize there are classes of problems where if you, you basically should work together on them because they're so fundamental.

Yeah.

That actually they will stop everybody from being more competitive, right?

It's like, so, um, thank you for asking that because that's actually very much, like, in fact, when we started the company, I made a personal decision not to go into the company, Commonwealth Fusion Systems.

Yeah.

And it's a wonderful company and it has amazing people in it.

And it's like they are going forward with their particular concept and that team towards building their prototypes and doing that.

It's like we need that.

But there are also a whole class of problems that if you look into the next five or ten years, everybody in fusion is going to face.

And that is basically this extraction of the energy, which we can get into more details of that.

Yeah.

So the way I look at my own personal commitment in this is that if I helped get commercial fusion going by helping start a company, incubate the technology innovation, finding the right talent to do it, and finding a cost-effective manner towards really advancing fusion, it's like we need to do that across the board of all of those things.

The SEMICON of fusion was probably going to be a large publicly funded laboratory that has that consistency around that vision, but aligns itself with an emerging industry.

There you go.

There you go.

That's basically my job is to do that.

So it's really an expansion and a multiplier to the things that I've done at MIT.

And by the way, MIT almost certainly is going to be a partner in this because as a leading academic institution in the world and starting to tackle those problems, we're going to— it's not an either/or.

It's like we're going to need everybody that we can actually to solve these problems.

And so how is this all going to work?

Well, the way that it's going to work is that primarily is to basically build technology.

Like again, if you go back to the semiconductor industry and the things which are challenging, like lithography and so forth.

Right, yeah.

There were government and public accessible labs that started to develop the underlying technology that could then go towards those things.

I was a part of that.

I was on a team that developed EUV multilayer mirrors in the— Bingo.

A long time ago.

And in fact, if you know about— in fact, that has another link into fusion, it turns out.

Oh, it does?

Yes, because the laser technology that was used for the ablation and basically the— To make the little EUV sources?

Yes, that came from fusion.

Oh, did it?

It came from laser fusion.

Oh, wow.

Yes, yes, which we don't take enough credit for.

Again, one of those examples of when you try really hard things, usually you figure out how to do other hard things.

Right, right, right.

Which has opened up incredible capabilities in semiconductor manufacturing, right?

Almost down to the atomic scale.

Down to the atomic scale, exactly.

That's crazy, right?

That's nuts.

That's insane.

Yeah.

Right.

So what are we looking at here?

What is the future of this economy?

Who's going to benefit?

Are there going to be, you know, the fuels don't have to be extracted in damaging ways, right?

Right.

Because we're talking water.

Yeah.

Yeah, yeah, yeah.

Right?

And small amounts of lithium, actually.

And small amounts of lithium.

Yeah, but very small amounts, yeah.

Okay, so what does that future look like, both economically and impact on humanity?

So I can speak to the generalities of that, right?

Yeah, the generality.

The generality is that this is the other feature of why you want fusion, right?

And it's because the access to this as an energy source is not an accident of the history of the geology that you have, right, or where you are, or access to some particular raw resource with respect to like a rare mineral or something like this.

Well, let me interrupt here because when you keep mentioning magnets, right, it's very much in the news now that they rely on these— Rare earths.

Rare earths, yeah, yeah.

And you notice that rare earth is one of the key ingredients in the new magnet technology.

except it's used at staggeringly small total amounts.

So in something that would be a fusion power plant, there would probably be maybe 50 kilograms, maybe, of that rare earth.

'Cause tokamaks are notoriously massive.

So 50 kilograms is a tiny fraction.

It's a trivial fraction actually of it, 'cause it's mostly steel and concrete actually is really what it is, yeah.

But this goes back to this, to the question that you asked, and in some sense links into about what the UKAEA is doing as well too, is that in the end, it's not about access— it is about access to something, but it's not about access to the raw resources.

It's about access to the knowledge base of the science and the technology.

It's about access to the ability to do— to actually fabricate these highly specialized components.

So what we often call supply chain, which is, I hate that name for fusion because the supply chain is like high-tech like you can't believe, right?

And then three, and it's the ability to actually financially lift them and organize them to the point where they're profitable.

So what's the financial upside for fusion?

Will it be, if independent, if private companies make fusion, are they going to be the equivalent of the Exxons of today?

Yes.

Yeah.

Yeah.

There's going to be trillionaires.

I don't want to say about individual wealth, but it's like— Wealth generated.

Wealth generated.

And why is this?

Because it actually goes to that number that I mentioned before, which is the economic multiplier of energy to economic output.

And so if you look at the world, then that actually is something like the totality of energy, not just electricity, the totality of energy, is somewhere in the $7 or $8 trillion per year.

There we go.

That's the market.

And for various reasons, which we'll probably talk about later when we get more into the details of fusion.

Fusion, if it can meet economic targets, has the chance to do vast displacements of basically all of those existing energy sources.

So what does this mean geopolitically?

So first of all, we've been talking about— renewables for a long time.

But there are forces that are like, no, we're making too much money with these non-renewables.

And then you have the issues of things like the digital divide, right?

Just because this community can afford to pay for internet and that community can't.

So when we look at, to take a word from an adjacent world, the proliferation of fusion energy generation, is it going to eventually proliferate around the world?

Will it be a case where nations will be able to take a, hey, you come and build our reactor, and then they take it over?

Like, what does that look like, that scale-up for humanity?

Yeah, it's a great— another question.

So it's the other— so we keep listing the reasons about like why fusion, right?

And it's like, and this is another one, which is that its expandability and its scalability into a wide variety of not just energy sectors or energy markets, but also geopolitically.

Right.

And as best as we can tell, and in fact, this is one of the other things that really has happened in the last five years, is that there's growing clarity about the regulatory environment for fusion.

And without getting too technical about it, it really stems into, one, it's a— and people assumed that it would be, I'm not sure why they assumed this, but they just thought, oh, this is going to be regulated like nuclear power plants, which have got some, if you follow that— Sounds natural.

No, no, it has some, and that has some real challenges about how you, when you export technologies into different political systems and countries and economies.

So fusion, so it looks like the decision, and this is another one where the UK in fact had the lead, they made an explicit and correct ruling that fusion would not be regulated like nuclear energy.

Because it doesn't have a potential downside effect that could be catastrophic.

Because of its inherent safety.

So things like Chernobyl are physically impossible.

You can't even do it even if you tried, right?

No meltdowns.

Right.

And then the second one is, and again, it's more, there's some nuances to it, but the general comment about how fundamentally different it is with respect to the control of special nuclear materials.

Right.

There's a little thing going on right now you might have read in the news.

Oh yeah, I heard about this little thing.

You heard about that little thing?

Yeah.

Which is real, it was really, and that's a very interesting example actually, because the enrichment of uranium is a necessary aspect, in fact, of operating a legitimate nuclear energy industry.

That's right.

But it's also an illegitimate aspect of being able to develop nuclear-grade weapons materials.

And so it's like, oh, so fusion, again, it's not that it has zero regulatory environment, because you have to have a proper regulatory environment, which is, of course, we want that, because we have that for everything, for planes, for fridges, and everything else, right?

But of course, we're going to have it for something like fusion, right?

Right, yeah.

And you still have to think through the issues about what this means to transport the technology around.

But it seems so fundamentally different and not directly tied to nuclear nuclear proliferation, that in fact, this is what my hope is.

And in fact, it's something that I work on, because I think here it's particularly to the design of the— this is where it comes to the specifics of the fusion designs themselves will be more or less translatable into other energy markets and into other countries.

But of course, it's our job as engineers to develop products which will just like go and fill up the energy ecosystem as much as possible.

And you want that both for the good of our ecosystem, but you just want it also because it maximizes the profit, which is totally fine as well too.

Those things can be mutually compatible.

They can be mutually compatible.

So it almost sounds like this is a step towards an all-electric world once you have electric power generation from fusion.

Not necessarily.

Not necessarily.

There are going to be some environments where high energy density transportable fuels are still necessary.

Exactly.

Yes.

Well, in fact, it goes— this goes all the way back to— like, if we want to loop that back in, it goes all the way back to energy density, actually, is that there's a reason we use liquid fuels for long-range transportation, like in airplanes, long-range shipping, and so forth.

You know, 60.

There's 60 times the energy density in liquid fuel than there is in an electric battery.

So that's very different going to your local grocery store than getting— than you and me getting a car and going to Los Angeles.

Right.

It's like those are fundamentally scales, right, around those things.

So here's where— and again, this will— I'm not going to describe the technicality of it, but this is where fusion— we're going to keep listing the things.

Like, why are we trying this semi-crazy thing called fusion energy?

Because fusion has another distinguishing feature.

And in fact, one that I realized primarily by working with economists, not my fusion colleagues, which is that it turns out that because the rules of nature force the thing that's making the energy, which is this very hot fuel that's in the conditions of a star, must by the rules of nature have no direct physical coupling to the thing that makes the energy product, that extracts the energy.

Right, yeah.

They must be— So it's confined by magnetic fields, and surrounding that is a vacuum.

And there's a— well, there's— but there's a— there's an object around it that's going to extract the energy in some— like to make electricity, for example, or whatever it might be.

But it must know nothing directly of the fact that there's a super— like there's a star in the middle of it.

Right.

And vice versa.

Right.

Which sounds like— that sounds really hard, Dennis.

It probably is.

Magnetic confinement?

Yeah, no, yeah, but, but this is very important because what it means is is that what you make with the energy is only limited by the cleverness of your integrated engineering, not by physics.

Ah, there you go.

Right?

And so he's like, why would physics limit this?

In fact, you already asked about this.

Like, oh, solar panel, physics, because it comes from how hot, in fact, how hot another fusion thing is, the sun.

The spectrum of photons of the light that hit a solar panel will forever set the energy density of that.

And the silicon things that— and the semiconductors that are basically in the solar panel must directly interact with and convert those photons into electricity.

They have a direct coupling to each other.

They do.

A gas turbine has to be designed at the temperature that you burn the gas at.

Right.

Because there's a physical coupling between them that must be there.

Fission, the water that's going by the fuel rods participates in the moderation and the criticality of the fission device.

So there's a direct role in that, but that's the energy product.

There is no such coupling in fusion.

Right.

So if you say, Dennis, show me a fusion design where the— let's say we're making heat for some process.

Can this be at 300 degrees, 800 degrees, or 1,500 degrees?

Yes, is the answer, the physics answer.

I don't know if that's the engineering answer yet, but that makes it almost unstoppable with respect to how much it can expand into, in terms of an energy product.

And so to be clear, in the first— like, we're kind of skipping forward— in the first implications— sorry, implementations of fusion, almost certainly is going to be electricity.

Right.

Just because it's a very, you know, straightforward— in a relative way, straightforward.

Like, you make the heat, the fusion comes out, fusion products heat up the thing, you bring out the heat, then you put it through the standard.

And then because after that, everything's fairly standard because all the generating technology and things like that.

But after that, who knows?

So when you look at economics, things like location matter.

So because of fusion, is it something like you'd put in a city center because you don't have the big danger and that might be the most efficient place to distribute it?

Yeah, so here we go.

Then here comes the next advantage.

So we talked about its ability, we believe, to be distributed around the world, which is also why it's part of a geopolitical race as well too.

Oh my gosh, right?

Right, yeah, big time.

But then you look at its siting, and in fact, here there's growing clarity, but it's not all set at this point, because there will be a regulatory environment.

I mean, it is an object that makes a lot of power and a lot of heat.

Yeah.

So you still have to take these things into consideration.

But right now, the objective would be, again, this is where we need to get our act together in fusion and come up with the best set of integrated technologies and/or different fusion configurations, which we haven't even talked about that.

There's an enormous— We'll get to that next.

Yeah, there's an enormous ways to get to— I actually want to see three or four different fusion energy concepts and energy products come forward, 'cause they're gonna be able to fill the ecosystem in a better way.

And then the details of this will be, the general conclusion is that it'll be much more expandable or flexible with respect to where you site it.

You know what, since we're getting nerdy, man, let's take a quick transition moment here.

Yeah, okay.

And let's unpack some of these nerdy details, 'cause what we've talked about so far are you, your new position, the economy that fusion is gonna bring about, and why fusion is the way to go for the future.

So just a warning to those of you who want the really juicy, delicious nerddom, that's where we're about to go.

Yeah.

Okay, so let's get to some nerdy stuff.

Nerdy stuff.

So, you know, we talked about the fact that there are different types of fusions, and I gotta read here, 'cause I'm gonna give you some lists of these— Test time, yep.

All these different fusion companies and organizations.

We have Helion, we have the National Ignition Facility, General Fusion, Commonwealth Fusion, we have Stellarators, we have Zap.

How do we make sense of the differences in all these different companies and approaches to fusion?

Some get like, oh, this is great, in January, then by March they're like, yeah, I don't know, like Stellarators, right?

They got a lot of excitement, then it was like, yeah, I don't know.

And then it comes and goes, yeah.

And like anything that's complicated, so actually I'm gonna pull up a whole level.

Okay.

Right?

It's like, so why does it look so diverse?

Like when you see these things and you see these companies and you see a, like, you're going to be my sample of one on this, right?

Okay.

So you probably see these news articles, right?

And you see one from Commonwealth Fusion Systems and you see this like big magnet.

Yeah.

And everybody's going, holy cow, this magnet.

That was me.

Because it's like, yeah, because that was one of the foundations of the reason for starting Commonwealth, which is focused on this new magnet.

And then all of a sudden comes out, then you see a picture of the National Ignition Facility and this, this enormous laser.

Right.

Okay, I thought it was a magnet.

Right.

Oh, now it's a laser.

Oh, and then, and then you see something from Zap.

Yeah.

And, and you're seeing this little, you know, very compact thing where there's basically a set of capacitor banks and this little, like, it's like, what, what happened to the magnets and the lasers?

Right.

Yeah, it's like— Where's the big giant building?

Yeah, yeah, yeah, yeah, where's the things?

Like, right, it's like, so why is this, right?

So I'll actually— this is really important to understand because it comes from a fundamental physical principle that's required for fusion, right?

And what that is required— so we have a name for this, it's called the Lawson criterion.

I've taught this like 100,000 times maybe, right?

Yeah.

And it's actually, it's extremely simple, but it's also extremely profound what this tells you.

And what you end up with is that there are, like in any relationship, it turns out that you can separate the variables that control, and there are three variables that actually— Right, right.

That set it.

So one is the most famous one, the temperature.

And the temperature of the fuel, and in fact, so for the most commonly used one, it turns out that there are minima in temperature that you must be if you want to achieve particularly ignition, which is when the fusion power is finite, but the external power is zero.

So basically it's completely self-sustaining.

Wait, once you get ignition, you can actually get a self-sustaining plasma?

Yes.

Oh.

Yes.

Wow.

Which is called the sun.

What?

That's igniting—No, no, no, no, no, no.

See, because here's the thing.

There's a constant input of gravitational energy.

Yeah, but the gravity does nothing for fusion.

It keeps it dense.

Well, no, ah, but that's actually not what makes the fusion reactions happen.

Otherwise you would have—Density matters.

No, no, but we would have fusion.

Oh yes, it does.

Ah, great.

Yes.

So density does matter.

If you go back to this, what you end up is you get a plot, and you can see that temperature matters, and that there's a minimum temperature, like for the most common kind of fusion fuel combination, deuterium-tritium, it's about 50 million degrees Celsius.

But it turns out that this actually, the shape of what temperature you need strongly depends on two other parameters.

And those other parameters is the density of the fuel.

Yep, yep.

Which is just the number of particles in that volume or per volume, right?

Right.

And something which we call the energy confinement time.

And what is that?

Well, this just goes back to this analog that I said of if I put hot water into this cup and I just watch for it to kind of like cool, the characteristic cooling time is the energy confinement time of the system.

So you don't have to even know anything about it.

It's just actually, it comes from thermal— It comes with thermodynamics.

It's just basically the characteristic time that it wants to cool.

So you don't have to know anything about what the process is that does it.

So in the end, what it turns out is that this plot, which is very famous in fusion, actually has the temperature is the independent parameter.

So it's on the horizontal axis, right?

Oh, I see.

Yeah.

And on the vertical axis, and this is where it gets wild, is the density and the energy confinement time, but it's the product of those two.

Okay.

Oh, well, what does that mean?

Oh, well, what that means is that because it's the product of the two, is that any combination of those that give you the right product is what you're after.

And there's different ways of— I imagine there's many ways of manipulating— This is where fusion's diversity fundamentally comes.

Because if you think about the energy, if you think about the density of the fuel, like, in fact, we already talked about this a couple of times, like the fuel in your car, right?

Yeah.

And if you would think of ammonia fuel versus like gas fuel, so it's like these are maybe factors of two in difference or something like that.

Or if you think of different fission designs, the fuel is maybe different by 50% in difference.

And people, oh, this is a big difference.

In fusion, like literally the concepts that we talk about, like magnetic fusion, which is a very common one now, and laser fusion, which is also very prevalent.

The difference in the densities is 10 billion.

Whoa.

That's a big difference.

That's a huge difference.

But guess what?

The difference— and in fact, so the laser fusion is 10 billion— again, I'm using approximate numbers— 10 billion times higher density than magnetic fusion.

You go, oh, that's a huge advantage, isn't it?

Oh, yeah.

But the energy confinement time— Tiny.

—is also 10 billion times smaller.

Wow.

And you just go, oh, wow.

Yeah.

This means— so this is really cool from a physics point of view, but it's also confusing from a technology point of view.

Because when you look at this— and by the way, and there's things which are in those private companies that you commented to, they span this entire region.

And therefore, this means that the technology implications and eventually also the economic implications are profound.

Because you're changing this really important parameter, which is of great interest.

So is it true to say that these different technologies manipulate these fundamental parameters in different ways?

Some optimize for one and sacrifice the other and vice versa?

That's exactly what they do.

And then this is why fusion is this interesting example of integrated— so what you have to do is take that science realization and then combine it with engineering intuition and integrated design to put all of this together into a system that will provide the best economic pathway to, and the most cost-effective pathway to actually realizing this quite complicated system.

Wow.

Right.

Wow.

And this, so this is also, remember I talked about before about why has fusion been a little bit slower, right?

One of them is minimum power density, right?

And the other one, or minimum power, which just means the tries at it, like slower.

You gotta be hot.

You gotta be hot.

And that's actually, it comes from the Lawson criterion.

Underneath it, it comes, because what the Lawson criterion is describing is that the reason it's staying hot is because of the fusion reactions.

It's like, ah, okay.

Ah, yeah.

Now I got it, right?

It's like the fire has to be intense enough to keep the fire going.

Yeah, the fire needs the fire.

Fire needs the fire, right?

So, but you do that, and then the other reason is because there are so many different ways to do it.

It's just like, oh, so what should I concentrate on, right?

So now, now we can talk about the companies, because the companies— so hopefully this helps explain like why is it look so confusing.

It looks so confusing because this is part of fusion's allure in many ways, is because there's so many different ways to to actually get up to par.

So you're easier to be a, we're different from the others, invest in us?

Yes, very much so.

And this is also, I mean, personally, I like this because I love a good competition.

But in the end, from a holistic point of view, this is also why, again, combined with all those other parts of fusion, particularly this business about the fact that the energy extraction system has to be independent.

So that is common to all those fusion systems because it must happen at these temperatures.

Again, the Lawson criterion says something basically, you probably design it around 100 million degrees.

This means there can be zero physical contact of this fuel— Oh, absolutely.

—with anything else because otherwise the fuel will get too cold because they cannot coexist, right?

But if you take those two things together, namely almost infinitely adaptable energy extraction along with an incredible, like a factor of like 10 billion in these fundamental parameters, it's like, oh good, because what this means is that the ability to deliver different kinds of energy products at different kind of cost points and different kinds of efficiencies, we should figure out a way to get there, not just with one of them, but with several of them.

Then you have bespoke energy.

Yeah, exactly, right?

So this is also then one of the reasons why there's been an explosion of private sector fusion companies, because— and this is particularly where the entrepreneurial venture capital system does well.

It's like, oh my gosh, it's like there's all these trade-offs about one approach versus the other.

Where will they be good?

And venture capitalists, and then eventually, you know, and then at some point investors, and then at some point the market—Right, right.

Sort this out.

Yeah, they sort it out.

They sort it out, right, yeah.

And then in the end it's based on how good your product is.

Well, let's get down to the discussion of the fuel.

So here's a point I like to make about how stars work.

So everybody says, oh, it takes protons and combines them to create helium.

But when you get into the details, you see that the pp chain really has this bottleneck in the first step where these two protons have to overcome each other's Coulomb barrier and then quantum tunnel, right, to interact, to convert one of the protons into a neutron to create a deuterium nucleus.

And the deuterium nucleus doesn't have so much resistance to fusing now, right?

So deuterium, you guys will start with it, you don't have that first step.

That's right.

But then once you have that deuterium, it interacts with other isotopes.

So we've heard like, oh, we can mine helium isotopes on the moon, because that might be better than this isotope that we were thinking of.

So what is that realm of potential fuels?

And do the different fusion confinement and ignition technologies have more favorable fuels, or are they all agnostic to the different fuel types?

Yeah, yeah, yeah.

They're— right.

So I'll actually get to— so it's a bit of a zoo, but we'll just walk through the ones that are— as I commented at the beginning, is that there's an incredible array, actually, of fusion reactions.

Like, there's way too long to go through.

But I'll just talk about the ones that we consider, because there's basically two criteria that are required to consider it for a terrestrial energy source.

Right.

So one is that it has to have a high enough probability, this thing of overcoming the Coulomb barrier.

It has to have a high enough probability at temperatures that we think we can access.

Oh, by the way, the 100 million degrees, we've done in the laboratory many, many, many, many times.

Right?

Yes, which sounds like the crazy part of all this, right?

Yeah, we've actually done that.

Yeah.

So if you pick like 100 million degrees, then there's basically a set of those so that they have a high enough probability of fusing just so that there's enough reactions so that it can work.

Two is that they have net energy, large net energy per reaction.

Like this isn't the plant energy, it's just for each reaction.

Right.

And what defines large enough?

It's not a hard criterion, but it tends to be that it's net energy, obviously, right, out of it.

And it tends to be, and the number tends to be in the multiple MeV.

So we are getting nerdy here because, I mean— Millions of electron volts.

Millions of electron volts, which is the unit that we use to measure energy.

To put this into context, a chemical reaction, like when you burn coal or something like that, has one electron volt typically, again, approximate.

Oh, wow.

One electron volt.

And these are things which have above a million electron volts.

This actually goes all the way, this is the technical way of saying what I said at the beginning, that when you make fusion happen, 10 million times the energy density.

That is it.

That's it right there.

So, and in fact, the ones that we mostly look at have around ten MeV of energy, right?

So what are those ones?

So the most prevalent one that is considered in the private sector and for fusion in general is deuterium-tritium.

Deuterium-tritium.

So those are the heavy forms.

So deuterium, which we already talked about, which was a proton with an extra neutron added on, that happened at the Big Bang.

So we don't actually have to make it by— The universe made it for you.

And it's in this water right here.

You drink it every day.

Yeah, you drink it every day.

All safe, stable everywhere.

That's why the fuel— that's the wonderful thing, right?

Deuterium.

Tritium is then the next heaviest one.

So that's a proton with two neutrons on it, right?

And it turns out that that extra, the reason, and so this is one of the, is really right now the most attractive reaction that we use.

Deuterium-tritium.

Deuterium-tritium.

And the reason for this is because this probability of the reaction happening at 100 million degrees is several hundred times larger than any other fusion reaction.

Oh, wow.

And this comes about from an aspect of nuclear physics where that extra neutron creates a resonance in the reaction.

And the peak of the energy where that happens is actually very small, very, very small for a nuclear reaction.

So it's only about a 10th of an MeV.

And if you remember from your textbooks, most nuclear reactions happen at MeV for exactly the reason that we talked about, because that's the characteristic energy of nuclei, right?

Yea.

Right, right.

So it's got this wonderful combination of that.

So it has a, again, to get nerdy, it has this probability is measured in a unit called barn.

And the very highest— The cross-section.

The cross-section, the cross-section.

And most nuclear reactions, the very significant nuclear reactions happen at one barn.

This has a peak reaction of five barn, which is like staggering time.

And as I said, about 100 to 200 times bigger than any of the reactions.

Listen, I think we've confused our audience enough.

I think that's a lot.

Let's get back down to earth and let's talk about, we mentioned the company you helped to found many times, Commonwealth Fusion Systems.

Now, I lived here in Massachusetts, then I moved to Virginia, so I got Commonwealth all in my blood now.

I used to live in states, but lately I've lived in Commonwealths.

So how did you get the idea for this?

You mentioned that there was a new magnet.

Was that the inspiration?

You saw an opportunity created by a new technology?

That's right, right.

So it came about from the realization that a new class of superconducting materials was going to arrive.

What, 'cause they were higher temperature?

Higher temperature and they could tolerate higher magnetic field.

Oh.

So it was both of them, yeah.

So is it the case that other materials would sort of break down under the high magnetic fields—That's right.

From stresses?

So just to quickly explain, so this is for superconductivity.

And superconductivity is the state at which the material will pass electric current with no dissipation, with no energy loss.

So they don't get heat up.

They don't heat up.

It doesn't heat up, right?

So this means you don't actually have to use electricity to actually maintain the current in the conductor.

Once the current is there, it's just there.

It's there, right?

And so electromagnets, which is magnetic fusion, we use electromagnets.

which are that you pass current around basically in a loop to make a magnetic field.

Yeah.

So when you work through the numbers, you can't use normal conductors like copper and so forth because you will always spend more power powering the magnets than you can get from the fusion.

It takes longer to derive it, but just trust me, that's what the answer is.

So when we look at power plants, so while we use copper in experiments, it was always realized you have to move to superconductors for a for a power plant around on that.

And the limits to that are various, but one of the fundamental limits of the superconducting state, because it's essentially like a quantum state of matter, is that it doesn't like high magnetic fields.

Right.

And the high magnetic field will break down the superconducting state and make it not superconducting.

And there's a variety of other things.

So along came this incredible new material, these so-called high-temperature superconductors.

In fact, that was interesting itself, discovered in the laboratory in the late 1980s, won the Nobel Prize in Physics.

All the physics— you were kind of probably interested in physics, like the nerds were going crazy that this could be— I didn't know enough in the '80s.

Yeah, that's okay.

Everybody was going crazy, like how could this thing be superconducting at these incredibly high temperatures, meaning like 80 degrees above absolute zero?

Exactly, I was going to say.

Which is still pretty cold.

Minus 200 Celsius.

It's not millikelvin or is it low Kelvin?

No, no, no, no, no, but it's extraordinary.

But then it was started to be realized.

So we're talking liquid nitrogen?

Liquid nitrogen temperature.

And that they could tolerate very high magnetic fields.

So double whammy.

Right.

So that was in the late 1980s.

And around 2010, it took that long basically then for there started to emerge a very small capability in industry to actually produce these crystals in a form that you could actually have them on a conducting wire, or it's actually technically a tape, right?

Got it.

So it's more 2D than 1D.

Yeah, yeah, yeah, yeah.

So it's a thin tape, and they basically figured out a way to deposit these superconducting crystals on this very small— on this tape.

And this was the realization.

I mean, the origin story was actually literally walking down the hallway at MIT, and I bumped into a colleague who also worked at the Fusion Center, but tended to work on— he works a lot on plasma technologies applied into other sectors, not fusion directly.

Yeah.

And he was carrying this reel that looked almost like a movie reel in his arms.

I said, "oh, what's that, Leslie?"

He goes, "oh, this is high-temperature superconducting tape."

And I said, "what?

You can buy that?"

He goes, "oh yeah, I just bought this reel."

Wow.

And it was just emerging as this idea.

What year are we talking here?

This is about 2010.

Okay.

Yeah.

And I said, oh, I said, "can you send me some data on that?"

And I was looking at this data.

I was like, oh my gosh, this is fascinating.

So I took this tape data, and I walked into my fusion— which I was about to start teaching my fusion design class.

And I needed a topic.

And I said, you know what?

So what we're going to do is— I had a different topic in mind, and I changed it.

What we're going to do is we're going to see if we could design a fusion science experiment out of this new material.

Wow.

And it was really like a thought experiment.

It was no idea of a— See, our professors did that to us at Stanford as well.

We'd get a problem on an exam and we'd immediately recognize it.

Like for example, one professor said on an exam, a qualifying exam, we're going to make a missile defense system where we're shooting frozen turkeys.

And we were immediately like, yep.

He's working for somebody and they're using a projectile that's about the same mass as a frozen turkey and he's having us do the calculations.

So what role did the students actually play in developing Commonwealth?

Oh, they were at the lead of thinking through the adaptation of this new— So was that just, that was the first day with the tape?

Yeah, actually in that class were four, including, if you include myself, it was four of the co-founders.

Of the six.

It was six—Of the six, yeah, yeah.

So at the origins of it was, and then that kept— How long did you go from there?

Well, then it kept progressing.

And in fact, then I taught, and then that ended up with like five peer-reviewed publications, I think, around on that.

Wow, from a class.

From a class, yeah, yeah, yeah.

Wow.

Yeah, and this was always, 'cause it's a theme that keeps coming with me all the time, it's like it needed almost a class to do it because none of those students had ever worked on superconductors.

superconducting magnets.

And it's because the technology and its implications were so new, right, that it was almost difficult for people who had worked on superconducting for a long time to kind of like let go of the standard assumptions.

Like, they were— we were throwing all kinds of crazy ideas at the fridge, right, uh, on this.

And, uh, and some of them stuck, right, around on that.

Yeah.

So it was that aspect of like, this is where students and young people— it's like, it's why startup companies are started by young people, right?

It's just like because they're not saddled with conventional wisdom around those things.

And so that kept evolving, and eventually, and then the next version of the class was really the beginnings of thinking of like, we designed this research device, oh my God, like the implications.

So now let's build it?

Well, no, the implications of it where I realized it's like we should be thinking of this towards really advancing fusion energy, like just outside of the research topic.

So we took, basically it was the idea of taking ITER, which is like a very, like still under construction.

And this was like in 2014, 2013, the class was taught.

And I said, let's take that design and that physics and we're going to see how small we can make it by using this new superconducting technology.

And that was ARC.

Yeah.

And after that paper came out, like the bells started to go off on a variety of— It took, I mean, it took a while, but it was a realization.

It wasn't just a technical innovation about using this new superconducting magnet to make fusion much smaller, but it had all other kinds of development and economic implications.

And that was the origins of— then Commonwealth came out of that.

So I want you to tell me two things really quick.

One of them is really fast.

How do you go from total time from concept, the day you see the reel to the formation of the company, that duration?

And the second question is, you mentioned ARC.

So I want you to tell the audience about ARC and SPARC.

Yeah, so that was about seven years.

Seven years.

Yeah, between that, because it was like three classes.

I also became the director of the Fusion Center in the intermediate.

So this is like a background project?

Oh yeah, yeah, well, it was a background project.

In fact, they literally had the students who then became students and then were postdocs at MIT had a funny— they call it the SPARC Underground, because they were basically bubbling this along with the idea, hey, this could end up as a company, this could end up as a project.

We owe so much to them, right?

I love their ability to think through those things.

So that was that.

So what did that end up being?

And the reason it's called the SPARC Underground, not the ARC Underground, was that we kind of sat back and looked at this, and we realized collectively, it's like ARC was— because it was this thought—What is ARC?

ARC is, basically, it ended up being a design for a prototype fusion power plant.

Got it.

Kind of a little bit by accident, almost, set by the design goals that I had put in the class, right?

But if you looked at it, you go, oh, wow, that's like too big of a chunk to take off, like to just try that right away.

So let's think through, and in fact, through a variety of different pathways, including who was in that original class, who's now the CEO of— Bob Mumgaard, who's the CEO of Commonwealth Fusion Systems, and his friend.

And his friend was actually quite experienced in entrepreneurship.

And they basically took— I love this story, right?

They took the ARC paper, which is a scientific paper, flipped it over, and said, how would we create a company that would be able to build this?

Wow, nice.

And then one of the other ones was we realized it's like technically it was too big of a— chunk to take off.

So how would we take this technology and design something really compact, really small, that would have everyone know that fusion worked?

And that was SPARC.

And so SPARC was an adaptation of that technology to make it even smaller, but not have the full mission, basically, of a fusion power plant.

And SPARC is what is now 80% complete in the suburbs of Boston, and is about to turn on.

Oh, wow.

About equals months, a year?

About in a year-ish timescale.

Wow.

So mentioning all this, you have a colleague.

This is tough, but your colleague Nuno, tell us about your colleague Nuno.

Yeah.

So Nuno was a professor at the— a colleague of mine in nuclear science and engineering and a pioneer in plasma science.

And plasmas are the core thing that we make fusion happen.

He was the discoverer of one of the most profound, and in fact solved a 50-year-old mystery about how magnetic reconnection, which is a very important phenomenon that happens in plasmas.

I remember the phrase sweet Petschek or something like that.

Sweet Parker.

Sweet Parker.

Wait, what am I thinking?

Where the hell did Petschek come from?

I don't know.

It's the P. Is there another Petschek process?

Oh yeah, sweet Parker.

Yeah, sweet Parker, which was a process.

And it's because plasmas can make magnetic fields and they're also contained by magnetic fields.

So it's a very complex relationship about how they— and reconnection is this basically tearing apart.

Like usually you think of magnetic field lines, like if you think of the— Continuous.

Yeah, continuous, like the iron filings around the horseshoe magnet, things like that.

It's like ripping those apart and rearranging them very quickly.

And people could not figure out like what on earth was going on.

I did magnetohydrodynamics as a graduate student.

There you go, it's MHD.

So I didn't know until later, after I graduated, that people who do MHD must be crazy to make that choice.

It's very, very hard.

It's basically the science of electrically conducting fluids.

Fluid mechanics is hard enough, now they're electrically conducting things.

You still can't solve the fundamental equations of fluid dynamics, the Navier-Stokes equation.

Now add in electrodynamics.

It's very, very hard.

Spoken from the MIT professor.

Yes, absolutely.

And so Nuno really cracked that, and he discovered that there was an underlying set of essentially layered instabilities that basically cascade away to create this very fast reconnection called plasmoids.

So brilliant, brilliant scientist.

He was also my successor as the director of the Fusion Center at MIT and was carrying on the legacy of leading-edge technical research alongside of leading-edge science research and education and so forth.

Unfortunately, he was murdered at the end of last year.

So in fact, we just held a memorial service for him at MIT with people who came from the fusion world from around the world to actually honor him as well too.

That is amazing, man.

And when I've seen people like your friend who passed away, and I attended their memorial services, it just, I'm always blown away by how many people come, how impactful, you know, I felt like it was platitudes, and I would hear professors say, oh, you know, how important their students are to them, both the researchers as well as their students in their classes.

And, you know, I got enrolled, and these people mean so much to you, but you don't really know as a professor.

How often, how many people's lives you impact, and how many people hold you in their heart.

Oh, it's the best part of the job.

You can't be— once in a while— so I've had the privilege to see my students succeed.

Like, oh, it's a satisfaction.

It's hard to describe.

It's a satisfaction.

Like, we have a job where we get an amazing privilege, where we get to discover.

And like, there's kind of like a— my daughter, by the way, who's doing a PhD right now, is figuring this out.

Like she discovered something that her professor hadn't.

It's like, do you realize you're the first person ever, ever to discover?

It's like this, it's an amazing privilege, right?

All right, so when we talk about the future of fusion, my mind immediately goes to one of the other great endeavors right now that's the cutting edge, and that's humans in space.

So we're going to the moon, allegedly we're going to Mars, and they're going to need energy.

And not only that, if we have spacecraft, right?

So for example, my students and I developed a new propulsion technology, but it required a megawatt reactor that did not exist for space application, right?

Yes.

So because our, you know, we looked at it as an ion propulsion technology, right?

So what is the future of fusion in space?

Right.

And of course this becomes more speculative because of course we're going to have to develop terrestrial fusion systems before we get there.

But the features of fusion that we mentioned, energy density, this aspect of— Wait, before you go, I want to add one more phrase that we use a lot in the spacefaring world, and that's ISRU, in-situ resource utilization.

Yes, yes, yes, exactly right.

Well, actually, there's another one, specific impulse.

And specific impulse.

You know that one as well too, which is very important in those.

So it's clear that fusion's features actually have a lot of advantages when you think about these uses.

And what I would say, places where the environment is highly constraining, right, around them.

And then it turns out it has an interesting connection into space travel because a lot of people, when they look at it, go, we probably want high specific impulse, which just means high velocity of the exhaust particles.

Yeah.

And that leads you almost naturally to plasmas, which of course have a strong link back into fusion itself as well too.

Right.

So actually, there are companies, there are private companies now looking at ways, their technology maturity is less, but they're looking at ways to exploit fusion for space travel.

But there are, and there are also simultaneously companies which are looking at using the technology of fusion a little bit like the one that you mentioned, but there's others as well too, about how to use particularly the plasma and magnetic technology, which primarily were developed from fusion, to actually get significant improvements in terms of propulsion performance as well too.

So they're sort of like spinoffs.

Yes, yeah.

So in fact, one of those is one of these other companies that I've been helping getting off the ground, which is an adaptation of the magnet technology we developed in fusion towards greatly improving the efficiency of thrusters that would be used, for example, in large-scale space propulsion, but also for things like microsatellites.

Oh, nice, nice, nice.

So these new magnet technologies will be used in those micro— wow.

Yes, yeah, yeah.

What about fusion on Mars?

Fusion on Mars, yeah.

So we actually did the— so it's interesting, after all this work, so this turned out to be, I decided to change up, I decided instead of just making only a design that might change the world's energy markets, that's too easy.

Let's actually try to develop an energy source, and the idea of it was I want to see a self-consistent plan for colonizing Mars.

Okay, all right.

And that means getting to Mars, getting there safely, right?

Without— and then if you want to colonize any place, you actually have to have energy because you have to have energy to be able to do the things you're going to do.

Well, let me ask you another question on that before you go into that because another thing that, you know, radiation is a hazard in space.

And one idea for protecting yourself from charged particles is to create a big magnetic field around your spacecraft.

Yes.

So it sounds like your magnetic technology and your fusion technology might be useful.

So were you in my class?

I was not, I wish I was.

It sounds like you were in my class because that's exactly what we came up with.

So you're ready for how we applied.

This basically was, and it's another sign of when you make a technology innovation, it has implications in lots of other things.

So what did we do?

So first of all, we designed a different kind of fusion.

So at its core was the idea of a fusion device, but it actually used an adaptation of the magnets in a different kind of topology called a mirror.

But in particular, its approach was that we use that one because we know that there's thorium on the surface of Mars, and thorium is a so-called fertile material.

So you can actually use the products that come from the fusion reaction to self-consistently keep making fuel on the surface of Mars.

Fusion fuel?

Yeah, fusion and fission fuel combined.

Because I know there are thorium reactors, like the Chinese ones.

So it's basically like a combination actually between these and in a way that garnered particular advantages.

So we'd use it in that one.

Right.

Two was we used superconducting magnets.

It was an adaptation of what you had commented to, which was like a new kind of plasma thruster.

So this has a magnetized plasma thruster, right?

Which is, I think, a little similar to what you were talking about.

This had variable specific impulse.

So we actually looked at these and that one required about ten megawatts because we were like trying to send huge spacecraft to Mars in a very fast period of time, right?

Right, right.

Three, then we use these new superconducting magnets for something called an MHD generator.

We talked about magnetohydrodynamics— Yeah, I've never heard of this technology.

Yeah, so this is actually something that was kicked around actually quite a bit in the 1980s, but what it uses is that instead of trying to do direct heat conversion into, like with a turbine, into electricity, that what it uses is the direct products that are coming out of this hot hybrid fission-fusion device, and it uses direct conversion using— it forces the hot particles across a strong magnetic field to do direct conversion of that fluid velocity energy into electricity.

Okay, so is it the fact that they are charged particles that are moving, so they are an electric current?

Yes, yes, yeah, yeah, and there's a variety of ways that you do that.

do that.

But guess what?

That needs high magnetic fields.

Yeah.

So in fact, there's a consideration right now going on about a next generation of MHD generators that use this high-generating magnetic field.

So that's three different uses of those magnets.

And then the 4th one, which is the final one that we glommed onto because we kept looking at this and going, oh my gosh, it's like the ability to shield the astronauts, the colonists actually on their way to Mars, is very, very challenging because there's very high energy, very high energy charged particles in the so-called background plasma, cosmic radiation.

And guess what?

We have a way that protects us on Earth that's called the magnetic field of the Earth.

That's right, the magnetosphere.

The magnetosphere.

Not to mention the heliosphere.

Right, which is produced by currents which are going inside the Earth which produce the magnetic field which goes around us.

Fantastic.

Yeah.

And, you know, very much like MIT students who do, like, we sat down and we looked at it and we go, oh my gosh, it's like, what if we made basically a magnetosphere that we carry with us?

Yeah.

So that was— so the idea was a circular magnet— Right.

Right, that makes that— and then when you look at it, you go, oh yeah, it looks like the Earth's magnetic field, and it deflects the the charged particles to keep them from hitting into solid objects.

So it deflects them.

That's what magnetic fields do to charged particles.

And the astronauts would live inside the magnet.

So what happens when humans in interplanetary space are living inside a magnet?

Yeah, so it's not as crazy as it sounds because it's an electromagnet, right?

So just have to distinguish, this is not a permanent— this is not like the magnet that goes onto your fridge.

The magnetic field is produced by an electric current, which is in some pattern that produces that field.

Okay.

So what you do is you use an aspect of electromagnetism that tells you that when you make an electromagnet, if you go to the center of the place where the electric current is being produced to make the magnetic field, there's no magnetic field there.

Beautiful.

Beautiful.

So they are now subject to these strong fields.

So it can't quite get down to zero because you couldn't actually have people live in the— 'Cause the magnetic fields are very strong.

Sorry, we'll have to use a unit.

So it's what, ten Tesla?

Okay.

Very, very strong.

So to put that into context, that's about 10,000 times the Earth's magnetic field.

'Cause it has to be so much stronger 'cause it's in such a, so much smaller of an object, right?

To provide the same kind of relative protection that the Earth's magnetic field does.

So people cannot, you can't, well, I mean, in some sense you can live, but at around five or six Tesla, I think.

Humans start to hallucinate pretty badly in a magnetic field.

Wow.

Yeah, yeah, because your brain, your neurons basically, and the chemicals which are in your brain have enough of a magnetic dipole moment, is what they're called, right?

That basically they start getting changed by too strong of a magnetic field.

Wow.

So anyway, so we can reduce the magnetic field low enough, and then the idea is that the mag— and so the idea that they would be living in the part of the magnet, so you get the good things from it, which is the strong magnetic field deflects the energetic charged particles, but they don't hallucinate.

So you reminded me of something.

I just wrote a book, came out at the end of April titled Why Do We Exist?

And I talk about the future of humanity.

And I talk about, I look at this idea that people have of, oh, we're gonna have to leave the Earth because the sun is expanding.

So we're talking billion years out here.

But that whole notion of, oh, aliens are coming 'cause they had to leave their planet.

Yeah.

And I thought about it, and I was thinking about this after the NIF result of net fusion came out.

I was like, wait a minute, we got fusion now.

If you can do interstellar travel, definitely you can do fusion.

So why do you ever need to leave your solar system?

Even if the sun goes out, we can build our own suns.

We can be on Titan, right, with fusion reactors in orbit and on the ground.

So you're talking about taking the magnetosphere with you.

I'm talking about creating artificial suns.

Is all of that really possibly in our future?

Could that be?

Yeah, I mean, of course, again, it becomes more speculative because you've gotta push the technologies so hard.

Absolutely, yeah.

But I almost wanna say the fact that we're talking about any of this anyway that we've made these artificial stars, that we've done all those things.

Like, you got to keep reaching, right?

And that's always what we've done.

I'll just keep going back.

We need, as a species, we need to keep trying to do the hardest things because they teach us about ourselves, what is possible.

Not all of it is possible, but it's like, and by pushing ourselves, we open up new vistas because they are even hard to imagine without even— Without being there.

You can't see the next horizon.

Yeah, exactly.

So in the end, I concluded colonizing Mars is way harder than fusion on Earth.

That is a statement.

That puts things in perspective.

Yeah, well, because of how hard it is on multiple things at the same time, which is namely propulsion, radiation protection, energy in a remote, difficult place with no supply chain, but all of those things together.

So I said, okay, so then I went back to, let's go back to just trying things on Earth again as well too.

But it was also an indicator of— it was, again, from that idea came this idea for this new company, which was just like, oh, we should be thinking about smaller-scale things of the adaptation of this technology into those things.

So very, very, very exciting.

And who knows what the other parts of the future will hold in this, right?

Yeah.

It's like completely changing the makeup of of our energy supply on the planet Earth is revolutionary.

Well, there's other parts to this other than the technology, and you founded another company called Rutherford.

Tell me about that company.

So Rutherford Energy Ventures, named after my scientific hero, but ironically it was actually co-founded with another professor at MIT who's in the business school.

And his academic expertise is in how do you build financial instruments that can actually very effectively garner resources and make profitability in things which are at the intersection of different technologies.

Like Bitcoin.

Yeah, like Bitcoin, right.

But in particular, his approach was in biotech.

I see.

So how do you find— biotech is a very interesting thing.

Now we just take it for granted.

Of course we can finance things in biotech.

Developing one revolutionary drug costs you $2 billion or something.

How do you distribute these?

He has thought very, very hard about how you build financial evaluation and eventually financial tools that actually allow you to account for high technology risk, but enormous possible economic reward on the other side of this.

Let me understand if I get this right.

It's almost like a strategy, like if I want to win the lottery, I could create a strategy that buying a large number of tickets and once it reaches some threshold and then it's profitable.

So is this something similar where you have, you could throw away a lot of money or you could make a lot of money?

Absolutely.

Yeah.

But there's a way.

Yeah, absolutely.

And the way to do that mathematically is a portfolio approach of investment, which is that namely, so if you think of all the things we've talked about in fusion already, all its incredible opportunities of how it can fit into the ecosystem, but also its extremely wide variability and the fact that it costs a lot of money per try, these have all the features about why you would think of a portfolio approach.

And what does it mean by portfolio approach is that you take— portfolio theory is very common in financial lens because the idea is that you make investments in things which have a wide distribution of risks and rewards or technology risks or costs or things like this, right?

So you have to figure out about how to measure these things.

But in the end, what you're doing is that you're improving the return, or you're keeping things like— you're changing the ratio of the reward, the financial reward that you get to the risk that you have to assume, right?

So does that make this an analysis and investment company?

Yes, yes, it makes it both of those things.

So what we've done— and it's a fairly new company, we've only started about a year and a half ago.

We've built up a technical team, uh, that I basically personally assembled of like, like amazing technical talent that understands fusion science technology.

And we've put this alongside world-class economics, right?

And, and, and, and economics is more than just like the fundamental theory.

It's actually the practicalities about how you would invest.

So for example, here's a good example of this.

So when you think about a distribution in a technology, and we'll just pick fusion because that's the one that we're doing, is that if you make— it's a good idea to make investments, but ones which are given by deep knowledge about what their risks are and what their probability of success is, but also how much money it will take for them to get to the finish line.

Right.

But you— and then when you make— And is the finish line defined, and that's profitability?

Profitability, right?

And that's right.

And but then, then what you want to do is, but you don't want to make investments that are all of the same kind because you're basically making the same kinds of risks.

So figuring out correlations or de-correlations of risk within all of those things, right?

Yeah.

So we've been— we've had a very, how shall I say, positive outlook conversation here.

Let's switch things up.

How could all of this, how could this all go wrong?

Right.

So how can it go wrong?

So there have been cycles in the history of fusion, right?

So you can get the science wrong, right?

In some of the very earliest attempts at fusion, it was such a new system, a new physical system, they saw measurements and they misinterpreted them.

It's almost like, fusion is 30 years out.

Yeah, yeah, yeah.

Imagine that, imagine that, right?

And then there had to be a maturation basically of measurement techniques, of understanding of the physical systems, and so there needs to be continued diligence basically that the underlying science is actually— in fact, I had a long-time, a very long-time friend of mine come in, and there's always these debates about in any kind of new technology sector, like about underlying science discipline versus like the applied aspects of it.

Right.

And it's like, and of course in fusion, you're never going to escape the fact that it's fundamentally like a challenging thing actually to make.

Right.

So we need continued diligence in that and making sure, and it's interesting in a competitive, like one of the things that it can, that can stop it is that we don't figure out frameworks in which we can protect sensitive information because it's being done by investors and through companies and so forth, but it still has scientific validity.

So how do you run it?

So it's one of the things we've thought about in Rutherford, for example, is that in some sense you need agencies which actually can treat the information confidentially, but actually have extremely high levels of confidence in the underlying science to make sure that it's not— because it could be prone to things where the underlying science claims are not actually all that they seem to be, and you need to be very diligent about that.

So that's one place.

The second place is an obvious one, which is this energy extraction aspect, right?

Right.

So you've made this rather exotic energy source, which is the plasma and all these particles coming out.

Now you have to build integrated components that can meet all the challenges of this, which is putting it into an environment, for example, where it's changing the identity of the atoms which are in the components that you build.

That's why it can change mercury into gold, but when you put steel in front of it, it changes it into a new atom.

Right.

Not like it's— it changes it into a new atom.

Just think about that.

My steel became wood!

Yeah, yeah, no, yeah.

Not quite that.

But it changed— Well, because what I'm getting at is, what if it changed it to a material that has properties that are no longer favorable for a reactor.

Exactly, exactly.

So when you look at that, for example, you put iron in there, even the isotope of iron matters because it actually changes how then you have to handle the product of it because the radioactive products that can come, which are temporarily activated by the fusion device, come from the choices of your engineered materials around on those things.

So these processes which have to do with extraction of the energy, extraction of the fuel and the ability to maintain these devices in a timely and efficient manner will clearly be the next set of integrated technology challenges that we have.

And our relative level of readiness is lower in those because we've spent most of our resources and we've trained most of our people in making that first part happen, which was really hard about making the fusion thing happen and all that.

Yeah.

So that's the thing that— that's— so progress slowing down, or I'll put it the other way, if we are not as innovative in the second part as we were in the first part, then it will clearly slow down our progress towards integrated fusion products.

And then the third one is that, and then when you put all of those constraints together, of the science constraints of it, and then essentially the technology constraints of the thing that you put around it, can you meet economic criteria.

Because if it's too expensive to build or doesn't make profitability long enough, at some point people will just— the market will just go, I'm not interested in this because I just don't want to deploy this.

And then fusion will not confer the benefits that we really hope that it would.

And that third one is— Is that the one that keeps you up at night?

Yes.

Because the first one we've got a really good beat on.

Of course, there's still some challenges on it.

The second one, We kind of know how to ask the questions around it.

And what we particularly lack there is just experience with it because you kind of like the first one comes along, you build this object.

It's like you've never seen a car before.

And then, but how do you change like the brakes on it?

Right.

It's just like, it's like if you've never changed a brake, that might be a daunting— okay, once you know how to do it, you know how to do it.

It's possible.

It's in the realm of possibility.

But that last one, it's because it's the culmination of all of those things together.

And we have so many different approaches, so many different ways we could use the resources.

How do we find a really efficient way to get all the way to that last part?

And if we don't do that in an effective enough manner, then I think people will just get tired of it and not use the technology.

And you're using it in an evolving environment.

It's not like other energy sources are just there not being engineered to be more efficient.

But I just want to add two stories that this reminds me of in developing technologies.

And one of them is a diffraction grating, and the other has to do with relativity.

So my PhD advisor, we did spectroscopy, so he loved telling the story— Actually, that's what I did for my PhD too.

Oh, okay.

Nerd.

But anyway, diffraction grating, for those of you who don't know what that is, is basically a piece of glass with a whole bunch of little lines carved into it at like thousands of lines per millimeter density.

But they have to be equally spaced perfectly.

So he used to say to us all the time, like, yeah, you know, the diffraction grating was known from science, but in order to actually make one, it had to wait for the invention of the perfect screw.

'Cause in order to get those lines equally spaced on these small distances, you had to have a perfect screw so every time you gave it a little tiny fraction of a turn, it moved the blade forward by this perfect increment.

Exactly, precise amount, yeah.

Precise amount.

And then with Gravity Probe B, It's like, oh, when a planet like the Earth is rotating, it drags spacetime with it, and we can measure that.

And so they came up with that idea in the '60s, but in order to make the measurement, they had to invent the most perfect sphere on Earth, which took 30-some-odd years.

Yeah, yeah.

Yeah, so it's like you have everything together, and you have all the technology that you know you need, but then you can get to a point where— There's some next step, and you just can't get over it, and then it's like, oh— It just takes time and engineering.

Well, yeah, and it takes cleverness because at some point you've got a finite amount of resources and a finite amount of time to be able to get this done, right?

Like, those are great examples.

Bragg diffraction.

Bragg diffraction, yeah, exactly.

I mean, that was a set of equations that were written down.

It's like you realize, oh, this is— and then it took like how long?

I already mentioned one, the discovery of the superconducting material, right?

And then it takes 30-plus years to actually make a commercial product out of it, right?

So these are the things that make you pause, right, in these and realize is that there's a big challenge that's in front of us.

In fact, a lot of commentary that I make is to AI, right?

Because that's a really great recent example in front of us.

In fact, the intellectual foundations of AI and fusion came about almost exactly at the same time.

No way.

Turing.

Yeah, right, right.

Because it came about in the 1940s and '50s, right?

And what stopped, like, so the intellectual principles of AI, like the Turing test, right?

And then the things that were done by people like Minsky at MIT, for example, that they were built in information theory and all the— how these things would work, but they lacked the tool.

And the tool was high-performance computing and access to enormous datasets because you realize that you actually had to test them, right?

In a particular way.

You had to have the internet invented first and then all this information piled in there.

The pathway that you had to, like everybody thought, oh, well, we're just going to keep building, like if we just kept building things with tubes, right?

And then you talked about— You mean vacuum tubes versus transistors?

Yeah, vacuum tubes versus transistors.

And you just, people wrote science fiction stories in the 1950s about the ultimate computer built with like, and it's like the size of Boston and it's built with vacuum tubes.

And you realize you were never going to get there actually with that, right?

Right.

So it was this, it was this, it's never, it's not just about the intellectual foundation.

Of course, that's you need that because that gives you the imagination to see about what it might be.

It's this crazy set of circumstances of how these things and people and organizations that come along that can apply these technology and innovations, and then all of a sudden it merges into this new thing that you didn't realize was possible before.

Because when ChatGPT arrived, like, the intellectual foundations of ChatGPT were not a surprise.

Right.

But the fact that you could actually do it in something you could deliver to a customer was like, that was the great surprise.

So here we go.

Like, we are now launched on this endeavor in fusion.

And I'm going to work as hard as I can to see that all come together.

From what it sounds like, you've already done the impossible.

And it sounds like you have already found viable economic pathways, even if it's not that final product, in the intermediate, pathways, and I can't wait to chat with you at some time later because things are moving forward and they shall.

Thank you, this has been amazing.

Thank you.

Thank you, and if you ever need help on anything, I know a guy.

Yeah.