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Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

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Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#151

Post by DennisP »

beambot wrote: post #41

They're using a deuterium reaction? That's not bad (per se), but the neutron production can create difficulties: major regulatory hurdles (can be used for nuclear material refinement?), difficult to extract energy, and causes a lot of nearby material fatigue. Another big contender (IMHO) is Tri Alpha's aneutronic approach: http://en.wikipedia.org/wiki/Tri_Alpha_Energy,_Inc . Either way, cool stuff!

Fwiw, high school kids build small reactors and fuse deuterium with basically no regulatory hassle at all. Lots of larger fusion experiments use deuterium too and do fine. Getting permission to experiment with fission is far more difficult. I'm sure there will be some regulation but it's unlikely to be very burdensome.

Boron fusion is pretty much the ultimate of course.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#152

Post by BugBrother »

tjradcliffe wrote: post #142
marvin wrote: post #138

Earlier quoted context omitted.

This is a simplification. Defending yourself against unprovoked attack is not juvenile, although there are moral systems that advocate rolling over and giving up if you are attacked. And there is a whole spectrum of combat actions where "defense against unprovoked attack" is one extreme. In industrialized countries, wars of aggression are usually never profitable, but the same can unfortunately not be said for less-d…

Actually, wars of aggression are almost never profitable. Accumulating riches via conquest is almost always a myth, because armies a) destroy much that is of value and b) are unbelievably expensive. "Wealth through superior firepower" has hardly ever been achieved. Even Rome mostly got rich through trade after its armies conquered Europe and North Africa, and a lawful peace was imposed. Had everyone been economically…

Interesting, you know more than me but afaik it is correct. Both in facts and arguably in moral.

Since you brought up Rome in discussing payback for warfare, you could also ask "Cui bono" here -- "who benefits?"

A war is potentially just like a gold rush, the people getting rich are the ones selling the tools to dig or make war.

Just look at my native Sweden, we managed to stay out of a few wars and shamelessly sold high quality steel to the countries fighting. It made Sweden go from the bottom to the top in Europe.

What this implies about lobbying and how wars starts I'll leave to the imagination.

(I might also add that IS has declared war on the democratic world. So trying to stop their expansion is arguably self defence.)

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#153

Post by ctdonath »

Dylan16807 wrote: post #97
rsync wrote: post #83

Earlier quoted context omitted.

"I mean, defense contracting is a bit of a drag and there's tons of red tape" Not to mention the tremendous moral hazard. I am unclear as to how anyone can function as a reasonable moral actor when they profit from war. Calling it "defense" does not solve that problem.

Generally I would expect direct fire weapons to have much less collateral damage than bombs. Building a better bullet can save lives.

And of late someone has: guided .50BMG bullets which can adjust their flightpath to assuredly hit a target (which, one can presume, is being shot to prevent others from being killed). EXACTO .50-caliber demonstration: http://www.darpa.mil/NewsEvents/Releases/2014/07/10a.aspx

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#154

Post by DennisP »

cletus wrote: post #115

As much as I hope this succeeds and as glad as I that HN is betting on such "moonshots", I remain skeptical about the practicality of nuclear fusion as a commercially viable power source. Fusion works particularly well for stars because of gravity. We're trying to use magnets to contain superheated plasma. The Sun generates less energy on a kg-for-kg basis that compost [1]. And it has gravity to contain the byproduct…

The second-easiest reaction is deuterium-deuterium. Half the time it produces He3, and the other half it produces tritium, which decays into He3. So start with D-D and bring in He3 as you get it to reduce neutron output.

Even with D-D alone the neutrons are a lot less energetic than with D-T.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#155

Post by DennisP »

tormeh wrote: post #37
sillysaurus3 wrote: post #32

Earlier quoted context omitted.

What is meant by eccentric science? Would you be specific?

Well, I don't know much about the subject, but the way I've understood it there's ITER and then there are a couple other reactor projects. Everyone except ITER is violating some kind of popularly held belief among physicists - they could be cheaper and better, but it's far from certain that they'll work at all. This just looks like another one of those.

I don't think it violates physicists' beliefs, it's just that they're more confident in tokamaks like ITER because they've been studied a lot more.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#156

Post by Chronic29 »

FiatLuxDave wrote: post #106
swalsh wrote: post #95

Earlier quoted context omitted.

Nuclear bombs aren't that dangerous though... in the grand scheme of things. That's because their use could trigger a chain reaction which creates a virtual apocalypse scenario. Basically ensuring their use impossible. What's scary is a weapon that can cause massive damage, that we are actually willing to use.

In the grand scheme of things, the situation that held during the Cold War was a historical accident. Not every nuclear bomb in the future will necessarily be possessed by nations who are facing adversaries who can respond in kind to the use of nuclear weapons. Nuclear weapons are very scary indeed, and we are very lucky to have made it decades since they have last been used in war. I have good faith that we will mak…

I, however, would make the bet that they never ever are used again.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#157

Post by lotsofmangos »

kghose wrote: post #140
rsync wrote: post #83

Earlier quoted context omitted.

"I mean, defense contracting is a bit of a drag and there's tons of red tape" Not to mention the tremendous moral hazard. I am unclear as to how anyone can function as a reasonable moral actor when they profit from war. Calling it "defense" does not solve that problem.

Plasma cannons don't kill people, people kill people, and we've already invented those.

Changes in topology kill people.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#158

Post by hindsightbias »

aetherson wrote: post #121
sillysaurus3 wrote: post #109

Earlier quoted context omitted.

Rather than a literal plasma gun, I think they were just saying the risk is that the team will pivot into weapons research. But no one has thus far explained why weapons research would be anything but a positive thing. Yes, using weapons is unfortunate. The decision to ever use a weapon should be made with the utmost discretion. But when it comes time to use a weapon, it seems hard to argue against having the most ef…

And what I'm saying is that regardless of the ethics of it, why should we regard it as in any way plausible that this company would pivot into weapons research? By a huge margin, the most plausible military application of anything this company develops is "a fusion reactor on an aircraft carrier." And I say that as someone who regards it as deeply unlikely that this company will create any major step towards a fusion…

Not big enough for a carrier, and that last generation is already designed.

But about right for a submarine.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#159

Post by sounds »

jccooper wrote: post #88
ChuckMcM wrote: post #39

Earlier quoted context omitted.

The risk of #3 is that they don't create fusion but they do develop a machine that can emit streams of hot plasma which is then turned into the Navy's weapon of choice for close weapons support on carrier battle groups. That said, I am looking forward to at least one of the fusion efforts bearing fruit. I'm something of an optimist here but I expect a durable solution to the 'energy problem' to emerge from our develo…

No doubt they could come up with something dangerous, but I wouldn't worry about that particular mode. Plasma doesn't travel far. A nice portable high intensity directed neutron radiation source might be pretty nasty, though.

Sadly enough, those already exist:

"Fusors have also been developed commercially, as sources for neutrons by DaimlerChrysler Aerospace" http://en.wikipedia.org/wiki/Fusor

But you're right, plasma is not the deadly weapon. Neutrons are.

Re: Y Combinator And Mithril Invest In Helion, A Nuclear Fusion Startup

#160

Post by malandrew »

soperj wrote: post #78
malandrew wrote: post #61

Earlier quoted context omitted.

I don't understand why this was downvoted. I'm not going to discount the possibility to invent something worse then our most powerful fusion bomb, but if we talk probability here, developing processes that allow greater control is likely to result in a worst case scenario where we have a weapon that is at most as powerful as what we already have, but more focused. IMHO focused fusion destruction is likely to be far m…

I'll never understand being able to kill someone in a humane way(through acts of war). You're killing someone.

If you were going to have to die some way, would you prefer to die from 3rd degree burns over most of your body and with your retinas burned from a bright searing light or would you prefer to die from a lethal dosage of heroin?

The outcome may be the same, but there's a whole lot more humanity in subjecting someone to the latter.

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