I'm a big fan of nuclear fusion as a concept and hope to shift toward doing active research in the field at some point.

I'd like to open this discussion to talk about topics regarding nuclear fusion as a future energy source. To start, I'll lost a couple of ongoing fusion efforts I'm familiar with.

ITER:Of course the biggest fusion project is ITER, the massive multinational collaboration which is building a massive tokamak reactor in France. Unfortunately ITER will never produce power for average people, as it's purely a test reactor with no plans to be connected to the grid. The following effort to build a functional grid connected reactor, DEMO, isn't set to be built until at least 2050. This has resulted in a considerable number of private ventures trying iut experimental alternative approaches.

HELION:At the time of writing this, there's quite a bit of buzz surrounding Helion energy, both because of the ambitious timeline theyve recently proposed as well as the investment of Sam Altman of OpenAI fame. Helion uses an FRC topology, which I personally think is a really cool idea. Basically it's a tokamak without the physical shell around it, and is kept sustained by the internal plasma physics. Helion also has another interesting quirk, they are not pursuing the typical DT fuel strategy, but are instead planning to use DD fusion to breed He3 and use DHe3 fusion as the primary energy source. I think this is a good idea because DHe3 fusion is "aneutronic", whereas DT fusion produces high energy neutrons that are somewhat of an unsolved problem to deal with. I wonder though, how they intend to deal with the inevitable tritium pollution that DD fusion creates, and how they will separate that out before Iit creates neutrons anyway.

TRIALPHA:In addition, another major company TriAlpha Energy, also pursued FRCs, hoping to use an alternative proton-boron11 mix to achieve aneutronic operation. I think they've sort of pivoted toward being more a neutron source than working toward breakeven.

HB11: A recent proposed approach is HB11, which is also going for proton-boron fusion. Now with Tri Alpha this seemed really dubious, because hydrogen boron has a much lower cross section for fusion than other options, even the DHe3 that Helion is doing. In addition, boron has way more electrons than hydrogen, so a proton boron plasma has more electrons with causes more bremsstrahlung loss. HB11, however, thinks they can overcome this through high energy laser acceleration. They want to use a high power laser to shoot a fuel pellet into a target. This supposedly will work much better than heating the stuff, because the laser will impart a specific impulse and thus the thermal spectrum of the impact will have a much higher Q factor centered around the cross sectional peak. I'm not really convinced on this, just because I feel like that thermal spectrum would only last for the first few atomic layers of impact before it doesn't really matter amymore.

CFS: The next option I would consider to be one if the most popular fusion startups is Commonwealth Fusion Systems. They have what I'd consider the most conservative approach, they are attempting to build a Tokamak design like ITER, but hope to reduce the size considerably by taking advantage of advances in superconductor technology with REBCO tapes.

W7X:The next reactor type I'll mention was in the news a lot a few years back, the Wendelstein-7X in Germany. This is a stellarator design, the crazy twisted car wreck of a thing you may have seen before. The stellarator is shaped that way so that it doesn't require an induced current like the tokamak to have magnetic helicity, because the shape does that automatically.

ZAP:Another well liked dark horse is Zap Energy. They're not as flashy as the other reactors but seem to be working off solid physics that have been proven out over many years. They're trying to do sheared flow z-pinches, which is basically creating a lightning bolt that's perfectly straightened out and super dense.

DPF:One more somewhat obscure option is Eric Lerner's Dense Plasma Focus approach. I'm a little puzzled by this option because it seems to be the exact opposite of Zap, where they make an incredibly twisty lightning bolt instead of a straight one.

FUSOR/POLYWELL:There are a couple reactor types that get mentioned often but are more or less obsolete are the Fusor and the Polywell. A Fusor is a neat device that can be built to fit on a desktop and still produce actual fusion reactions, but has a fundamental design flaw of a physical electrode inside the plasma that introduces too much conductive heat loss. The Polywell is a more advanced concept thay tries to create a "virtual" cathode with orthogonal magnetic mirrors, but I think after many years of experimentation researchers were unable to validate the formation of such a virtual cathode.

NIF:One option that is sort of tangential is the NIF, which you might have heard technically produced more energy than it produced. I dont think its necessarily going to go anywhere, mostly because it's more a weapons program than an energy program, but I think the chirped pulse amplification technology they use is really cool.

GENERAL-FUSION:And finally I'd be remiss if I didn't mention the very highly funded and publicized General Fusion. I definitely give them points for pure childlike wonder. The original pitch was they were going to take a giant swirling tornado of molten metal, fire a ball of plasma into the eye of the storm, then smash the whole thing from all sides with a hundred giant hammers. To be honest is such a wild concept that I don't really know if it really makes any sense or if it's a fever dream. It's undergone a few revisions after finding out that certain parts of its concept just weren't going to work. This doesn't inspire a ton of confidence, but also shows flexibility in their thinking.

There's definitely lots of other companies with other variations, but this gives a general idea of the huge range of ideas and approaches being pursued. I think it's a really cool field to explore and I'd love to hear all your thoughts about it.

https://www.businessinsider.com/gray-whales-or-devil-fish-friendly-to-humans-baffling-scientists-2023-7#:~:text=Gray%20whales%20were%20nicknamed%20'devil,humans%20pet%20them%2C%20baffling%20scientists.&text=Gray%20whales%20were%20hunted%20to,the%2018th%20and%2019th%20centuries.

Gray whales put up such a fight against whalers and their boats they earned the nickname "devil fish." Today, in the same places where the whales were hunted to the brink of extinction just decades ago, they swim right up to boats, enchanting and even befriending the people in them.

One of those remarkable encounters was captured in March in the Ojo de Liebre, a lagoon in Mexico's Baja Peninsula. The video showed a gray whale right beside a boat, allowing the captain to pick whale lice off its head.

Although some thought the whale was purposefully going to the captain for help with the whale lice — which are actually crustaceans, not insects — experts told Insider that's probably not the case.

Still, the fact that the gray whales of the Baja lagoons interact with boats and humans at all baffles researchers.

"This is what's so strange. They were hunted almost to extinction," Andrew Trites, director of the Marine Mammal Research Unit at the University of British Columbia, told Insider. "You would think being near a person in a boat is the last thing the few remaining gray whales would've ever done and they would've had this disposition to avoid them at all costs, the few that survived."

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A rare, half-billion-year-old fossil gives us a clue to how a bizarre marine invertebrate can possibly be related to humans. In a study published on July 6 in the journal Nature Communications, Harvard University researchers identified a prehistoric specimen in a collection at the Natural History Museum of Utah as a tunicate, or sea squirt. The preserved invertebrate, which was originally discovered in the rugged, desert-like landscape of the House Range in western Utah, can be used to understand evolution mysteries that go way back to the Cambrian explosion.

“There are essentially no tunicate fossils in the entire fossil record. They’ve got a 520- to 540-million year-long gap,” says Karma Nanglu, an invertebrate paleontologist at Harvard. “This fossil isthe first soft-tissue tunicate in, we would argue, the entire fossil record.”

https://www.popsci.com/environment/tunicate-fossil-cambrian-explosion/#:~:text=A%20500%2Dmillion%2Dyear%2D,the%20history%20of%20animal%20life.

https://undark.org/2023/07/05/neglect-of-a-museums-collection-could-cause-scientific-setbacks/

IN A DUSTY ROOM in central Florida, countless millipedes, centipedes, and other creepy-crawlies sit in specimen jars, rotting. The invertebrates are part of the Florida State Collection of Arthropods in Gainesville, which totals more than 12 million insects and other arthropod specimens, and are used by expert curators to identify pest species that threaten Florida’s native and agricultural plants.

However, not all specimens at the facility are treated equally, according to two people who have seen the collection firsthand. They say non-insect samples, like shrimp and millipedes, that are stored in ethanol have been neglected to the point of being irreversibly damaged or lost completely.

When it comes to how the FSCA stacks up with other collections she’s worked in, Ann Dunn, a former curatorial assistant, is blunt: “This is the worst I’ve ever seen.”

Experts say the loss of such specimens — even uncharismatic ones such as centipedes — is a setback for science. Particularly invaluable are holotypes, which are the example specimens that determine the description for an entire species. In fact, the variety of holotypes a collection has is often more important than its size, since those specimens are actively used for research, said Ainsley Seago, an associate curator of invertebrate zoology at the Carnegie Museum of Natural History in Pittsburgh.

A paper published in March 2023 highlighted the importance of museum specimens more generally, for addressing urgent issues like climate change and wildlife conservation, with 73 of the world’s largest natural history museums estimating their total collections to exceed 1.1 billion specimens. “This global collection,” the authors write, “is the physical basis for our understanding of the natural world and our place in it.”