DennisP

31 ms·

571.
by DennisP 2y ago
That's why fusion blankets for D-T reactors use lead or beryllium as neutron multipliers. CFS for example uses FLiBe molten salt. Doing it this way a tokamak can not only sustain its own tritium supply, but periodically provide startup
572.
by DennisP 2y ago
Series of short bursts, which heat a neutron-absorbing fluid. That part is relatively straightforward. Helion is an exception, since they have a different fuel which gives them a way to extract electricity directly.
573.
by DennisP 2y ago
I've seen cost estimates around there for tokamaks. If Helion actually works, their estimate is more like $20/MWh, and it looks pretty plausible given their reactor design. They would have relatively low neutron radiation, direct
574.
by DennisP 2y ago
Deuterium is not rare at all. There's enough in your morning shower to provide all your energy needs for a year. https://dothemath.ucsd.edu/2012/01/nuclear-fusion/ Tritium is rare but lithium isn't,
575.
by DennisP 2y ago
Healthcare doesn't depend on a job, and I don't understand why this rhetoric continues. Except in certain red states that refused federal funds, anyone below a certain income gets Medicaid and anyone above it can get ACA insurance
576.
by DennisP 2y ago
Lots of youtube videos are not the well-organized presentations you describe, but instead have a minute or two of good information with ten minutes of meandering asides, background you already know, and other fluff. Some are well-disguised
577.
by DennisP 2y ago
I don't, and yes. I suspect this varies by person.
578.
by DennisP 2y ago
It's not that, it's "too long with low information density so ingest it more efficiently." That way we can spend our time on things that are more productive or enjoyable.
579.
by DennisP 2y ago
I haven't read the study itself, but normal practice is to give the control group some kind of attention that doesn't include the intervention you're testing.
580.
by DennisP 2y ago
That actually sounds like it'd be really helpful.
581.
by DennisP 2y ago
A book I read a couple years ago (I think Peter Attia's) said one of the clearest nutritional studies just sent a weekly bottle of olive oil to half the participants, who had better health results than the control group. They didn&#x27
582.
by DennisP 2y ago
GP didn't say he was a punk, he said he had long hair. I think you're reading defensiveness into it, all I saw was a reasonably interesting point.
583.
by DennisP 2y ago
I don't think a second strike from asteroids would work. You can't just arbitrarily redirect an asteroid towards Earth whenever you want. You need one that's already going to pass nearby. You might have to wait decades for it
584.
by DennisP 2y ago
Sorry, what I mean is: why would I use my rocket and nuke to divert an asteroid years in advance, when I can drop an 8MT nuke on you directly in 30 minutes with much more accurate targeting? One possible reason is plausible deniability, but
585.
by DennisP 2y ago
In this case, the context is "we face the same risk all the time, from asteroids we don't see." I'm not convinced that's reassuring. The Sagan paper concerns much larger asteroids, which are correspondingly more rar
586.
by DennisP 2y ago
Because they completed the initial design in 2001, and broke ground in 2007. The superconductors became available in the early 2010s.
587.
by DennisP 2y ago
So you're calling it a "crisis" that people will be better informed of the risk they've always faced? Seems to me we should use that media coverage to build political support for a real asteroid defense system.
588.
by DennisP 2y ago
We actually do have commercially available superconductors that support much stronger magnetic fields than what ITER is able to do. I don't think it's 100x, but it doesn't have to be. Tokamak output scales with the fourth pow
589.
by DennisP 2y ago
If you're claiming that humans are born with more data than the six gigabits of data encoded in DNA, then how do you think the extra data is passed to the next generation?
590.
by DennisP 2y ago
Looks like actually three billion base pairs in human DNA: https://www.genome.gov/genetics-glossary/Base-Pair#:~:text=O... So six billion bits since two bits can represent four values. Base pairs and bases are effectiv
591.
by DennisP 2y ago
Or Nvidia keeps its earnings and our best frontier models get a hundred times better.
592.
by DennisP 2y ago
It was pretty neat seeing this because a recent paper found that AI models are bad historians: https://techcrunch.com/2025/01/19/ai-isnt-very-good-at-histo... But the gist of its argument just seems to be tha
593.
by DennisP 2y ago
Hmm I'm not convinced that human brains have all that much preprogrammed at birth. Babies don't even start out with object permanence. All of human DNA is only six billion bits, which wouldn't be much even if it encoded neura
594.
by DennisP 2y ago
As I wrote above, by itself gold is a terrible investment. But as a small portion of a portfolio that you rebalance periodically, it has its benefits for improving risk-adjusted returns. See my second link for details. But you can get the g
595.
by DennisP 2y ago
So it bubbled and crashed forty years ago. In the past 25 years it's had decent returns, and in particular: 2007: 31.59%, 2008: 3.41%, 2009: 27.63%, 2010: 27.74% [1] Owning too much gold is terrible, but a modest allocation to gold in
596.
by DennisP 2y ago
It does, but Bitcoin's transaction fees are just paid to the miners. On Ethereum they are mostly destroyed. Combined with the lower issuance of proof-of-stake, this means that the supply of ETH sometimes actually shrinks. That makes ET
597.
by DennisP 2y ago
ETH's supply growth without the burn maxes out at about 2% annually, in the case of almost the entire supply being staked. That's still less than major fiat currencies. Its current growth rate is less than Bitcoin's. For the
598.
by DennisP 2y ago
Proof of stake doesn't require that kind of investment. Ethereum for example has a large decentralized set of validators like Bitcoin, but runs on regular computers with the energy usage of a few hundred average American households. It
599.
by DennisP 2y ago
Well we do have an existence proof that human-level intelligence can be trained and run on a few thousand calories per day. We just haven't figured out how to build something that efficient yet.
600.
by DennisP 2y ago
Once AI becomes self-improving, using its intelligence to make itself more intelligent, exponential progress seems like the logical consequence. Any lack of exponential progress before it becomes self-improving doesn't have much bearin

More ›