Physicists discuss fusion progress at a Bay Area lab

Since the beginning of time, humanity has longed to create the sun. And for more than 70 years, scientists have known how to create an artificial nuclear fusion reaction, forcing positively charged particles to collide and fuse, generating enormous amounts of heat. It’s something the sun has been doing for about 4.6 billion years.

But every time humans have tried it in the past, it took enormous amounts of energy to heat up the protons and get them moving fast enough to overcome their natural repulsion for one another, far more than the reactions themselves have generated. . Containing the reaction, that is, preventing it from becoming a bomb, has also proved risky. Achieving those two goals has been a holy grail, a dream that holds tremendous promise for clean energy, long-distance spaceflight, and other science-fiction breakthroughs. It’s also been “20 years” since the concept has existed.

That all changed on December 5, at 1:03 a.m., when a handful of night-owl scientists at the National Ignition Facility at Lawrence Livermore National Laboratory bombarded a small capsule of frozen hydrogen with 192 intense lasers, forcing the atoms to bounce the container at an incredibly high speed. The protons in these atoms were positively charged, which means they repel each other.

But when they moved fast within a relatively small space… well, sometimes they couldn’t help but bump into each other. And forcing the protons together caused them to fuse, emitting a burst of gamma rays with 1.5 times the energy that the lasers had put into the capsule. It was the first time that scientists managed to trigger a process called ignition, the same series of chain reactions that power the sun, producing more heat than it put out.

In other words, they did.

The idea of ​​tabletop fusion has been a white whale to both scientists and consumers for most of my life. But now, the promise seems much closer to reality: truly clean energy. No uranium. No plutonium. No nuclear waste. No gas, no coal. Hydrogen in, energy out (and maybe a little helium). The lab didn’t explode. No one died in the reaction, or was transformed into a superpowered octopus. So congratulations. You lived to see the dawn of the fusion era.

…Or did you?

There are many signs that the narrative surrounding this discovery is a classic exercise in American salesmanship. First, experiments like the one NIF performed do, in fact, produce radiation, in the form of stray neutrons. They can make anything they pass through radioactive, and not in the funny comic book way.

More damning, the scientists only produced a net energy gain if you count the power of those 192 lasers, and not the power needed to run those lasers. These are very hot spot lasers, which means a huge amount of power is needed, hundreds of times the amount of power produced in the reactor. So the official energy surplus announced this week is something of an accounting trick.

“Lasers are an incredibly inefficient way of doing anything,” says Phillip Broughton, a healthcare physicist (if you’re wondering what a “healthcare physicist” is, Broughton says he’s actually a radiation safety specialist) and officer laser safety at UC Berkeley, who previously worked at the Livermore lab in a similar capacity. “It’s a lot more power on the wall to do the lasers… It’s a bull for power. It’s not a question of power generation, and it never will be.”

Broughton also pointed out that while the scientists were able to produce surplus energy from the fusion reaction, there was no way to HARNESS that energy. There was no water tank in his test room that would produce steam to turn a turbine. There was just a brilliant burst of heat, and then nothing.

Still, those limitations didn’t stop other physicists I spoke to from registering their enthusiasm (or, at least, their admiration) for what Lawrence Livermore’s team has accomplished.

“This is huge,” said Matthew Bellis, an associate professor in Sienna College’s Department of Physics and Astronomy and a member of the CMS Collaboration involving the Large Hadron Collider. “There is a joke that fusion energy is always 20 years in the future. You go back to when they started working on this, probably in the ’50s or ’60s, and they were like, ‘Well, 20 years to go.’ Then 20 years later, ‘Well, give us 20 more years and we’ll have this. We will be able to create more energy outside than inside. That’s the holy grail.”

Bellis, like Broughton, is well aware of the power requirements of those big honking lasers. He believes that what the NIF team did qualifies as ignition and noted that the techniques used could be applied by other laboratories, with more efficient lasers. Generating clean nuclear power was never a priority for the Lawrence Livermore Laboratory, which was clandestinely founded in conjunction with the Manhattan Project to ensure the safety of America’s now aging nuclear arsenal. Other laboratories, particularly in the private sector, have it has already been devoting enormous resources to this project; now, they have something much closer to a model for finding atomic gold.

There is also the possibility that this is less scientific breakthrough, and more than one psychological one, one that Bellis believes could accelerate a global race to produce fusion power on a commercial scale. Let’s be frank: if something isn’t going to happen in our lifetimes, we’re much less inclined to give a shit, whether we’re investing in a technology or voting for our government to do so. Now, today, it feels possible, even reasonable, to give a shit about the merger, because it might actually be coming. There’s a huge difference between something being theoretically possible and definitely being possible, and this event made the idea of ​​fusion much more tangible, achievable, to a lot of very important and weirdly useful people.

“Funding agencies can show the general public that this money is being spent on something worthwhile. I think that’s huge. I think it’s really great to be able to show people things like, ‘No, this is here.’ Now we just have to figure out how to scale it up,’” Bellis told me. “Making a proof of principle that humanity can produce the same conditions that occur on the sun, even if only for a millisecond, is huge in giving everyone confidence that there is a way forward for this type of energy.”

That confidence is no small thing. It has the potential to change both the way the world views fusion energy and the aggressiveness with which it pursues it. You have been told, many times, that there is climate apocalypse won’t stopthat democracy is in your deathbed, that arms will win, and on and on and on. It’s easy to forget that the future is unwritten and that humanity is far more resourceful than we are often credited with.

But listen. We went to the fucking MOON. We have put robots on Mars. We have launched two probes that are currently floating outside of our home solar system. Almost all of those breakthroughs were preceded by accidents, wrong guesses, opposition, tragedy, red herrings, and false hopes. Us i kept trying anywayWhat the scientists in Livermore did was a reminder that we have some control over our destiny, and that we don’t have to choose our own demise. What that destiny

We have to keep trying, and now hopefully we will. Because if we let reality stop us, we’re all going to die.

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