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Robotbeat

13,838 karma · joined February 3, 2017

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Robotbeat··on Kentucky man becomes the first humanist granted religious exemption from AI
Imagine a civil engineer that refuses to use a computer of any kind for his work. How much do you trust scribbled long division?

Edit: what about a civil engineer that refuses to use steel. Or Arabic numerals. Or a construction worker that refuses to use power equipment. A delivery man who swears off wheels.

Robotbeat··on Worlds more habitable than Earth?
Twice the rocket fuel or half the payload. Again, regular rockets can do this today, like the Atlas V 551/2.
Robotbeat··on Tesla Roadster
? Do you think a Lambo is a particularly practical car? Obviously it’s a stunt car. It’s doing stunts! And no, it’s not legal to drive around shooting huge supersonic jets around the car; that’s hardly a criticism.
Robotbeat··on Tesla Roadster
That would be impressive.
Robotbeat··on Tesla Roadster
You’d want to dry the water beforehand, like is usually done in such things.
Robotbeat··on Tesla Roadster
Then don’t make the deposit?
Robotbeat··on Tesla Roadster
Yeah, you can sell fighter jets to private US citizens, if the guns and stuff are removed.
Robotbeat··on Tesla Roadster
Hydrogen is 1/14th the density of air.
Robotbeat··on Tesla Roadster
It had 4700kg of downforce. It would’ve been quite a feat to make a vehicle (or prop, call it whatever you like) like that less than 1 tonne.
Robotbeat··on Worlds more habitable than Earth?
That is a totally different topic. We’re talking about a hypothetical, where Earth is 20-30% larger, not whether an identical copy of Earth but 20-30% larger actually exists nearby. We know such roughly similar exoplanets are common, though. In that size range and in habitable zone.

And again, 30% greater escape velocity just isn’t a challenge. Existing rockets could be used to reach LEO, like Atlas 551 (well, probably want 552 to reduce the gravity losses). And then you can use electric thrusters (which don’t have a hard Isp limit) to reach wherever.

Heck, we could probably reach LEO even if escape velocity was twice what it is. Even 3 times, if you include more exotic propulsion methods that we’ve done some testing for (nuclear thermal, etc). With staging, etc, it’s just a matter of a worse and worse mass fraction, not really whether it’s possible or not. And once you get to low orbit, electric propulsion allows much better scaling as you can adjust Isp higher (although reduces thrust and means it takes longer to do your mission).

Robotbeat··on Worlds more habitable than Earth?
There are a bunch of exoplanets in that size range, and we could probably contrive chemical rockets with over 20km/s delta-v if necessary. Nuclear rockets 30km/s.
Robotbeat··on Worlds more habitable than Earth?
This isn’t accurate. 20-30% larger diameter with a constant density would mean about 20-30% greater escape velocity (mass is radius cubed but gravity is inverse radius squared, etc). So instead of 11km/s escape, it’d be 13-14km/s. And instead of ~9km/s to reach LEO, it’d be about 11km/s. This is not at all a showstopper. Even in the 60s and 70s, we built rockets with enough stages to go land on the moon and return to Earth, which is a round-trip delta-v of like 14-15km/s, and the Soviets did this mostly with low Isp hypergolic propellants, not even hydrolox let alone an exotic propellant like nuclear thermal hydrogen or electric thrusters. We often just launch stuff directly to GTO or GSO instead of bothering with electric propulsion, so even today’s rockets (many of which also have high enough thrust to weight ratio, like an Atlas V 551) you could do it (and then probably rely more heavily on electric thrusters). Even with higher gravity losses.

It’d be more expensive, sure, but the idea that it’d be almost impossible is just not true at all. It’s a very common thing that even a lot of fairly smart people often say, though.

Robotbeat··on Whatever became of holography? (2011)
They're also useful for analytical purposes.

It's possible to do this with digital methods, too, but the lower spatial resolution of most digital LCDs and most digital camera sensors (compared to film) limits it somewhat. But I think it'd be more practical than the analog film based analytical holograms.

Robotbeat··on 100+ reactions to 100+ solutions
I don’t blame OpenAI for that. There’s a ton of weirdly politically motivated denial of AI being useful for solving problems that require new answers. This is one of the very few possible ways to objectively prove that AI can do that.
Robotbeat··on OpenAI, the Partition Principle, and Mathematics
Impossible to know without either more information about the actual occurrence or a deep understanding of the person making the claims. Just as OpenAI could easily be acting improperly, researchers who (understandably) feel deeply attacked by their problem getting solved right from under them might not be the most unbiased, either.
Robotbeat··on Our Project Suncatcher prototype satellite is in orbit
Starmind is 75W/kg to start. You assumed half that for some reason.
Robotbeat··on Our Project Suncatcher prototype satellite is in orbit
Terrestrial data centers are having a hard time connecting to power. What’s the good of a $40/Watt compute asset you can’t turn on? Spending $10 or even $20/Watt extra to get power by sending inference load to orbit starts to sound like a bargain, and that’s doable with today’s launch vehicles. With high reuse, that number drops to below $1/Watt for 24/7 power, which makes it cheaper than any terrestrial energy source. And the vast majority of compute load is inference. Part of the training process benefits from a large, coherent (ie low latency) data center, but that’s a minority of the load nowadays.

Also: low Earth orbit is already pretty low latency. A lot of people’s intuitions about space latency are from when satellite internet was based out of distant geosynchronous satellites, but even that is probably just fine for most inference workloads.

Robotbeat··on Nazi Germany had no hope of making an atomic bomb, uranium cubes reveal
Yup. The race-to-AGI-because-China in particular. I’m basically a China Hawk and generally in favor of AI development, but I can recognize the same pattern.
Robotbeat··on New York thoracic surgeon: "For many patients 9/11 is not over"
I bet that happened for no reason at all, just like how the US went into Afghanistan for no reason in 2001.

(Sarcasm aside, there obviously are big problems for how these 2 nations responded to the massive terrorist attacks. But I kind of think it’s questionable to pretend there was no big terrorist attack that triggered the response...)

Robotbeat··on More questions about whether researchers can trust OpenAI with unpublished math
Neither? Competitive academic researchers are susceptible to exaggeration and self-aggrandizing, and CEOs are that and also mostly psychopaths. I tend to think there isn’t systematic spying on researchers looking for breakthroughs. A lot of people are looking for the same things using similar approaches.
Robotbeat··on Growing proof that autonomous cars save lives
I think people are just incredibly bad drivers when drunk, but they do it because they don’t want to hire a cab or leave their car at the bar overnight, etc. Having FSD handle driving would be way safer.
Robotbeat··on Growing proof that autonomous cars save lives
Things require resources regardless of “capitalism” or some other system.
Robotbeat··on Growing proof that autonomous cars save lives
It is, at least in a place like LA. Fares are like less than 10% the actual total cost of an average bus ride. https://www.reddit.com/r/LAMetro/comments/1orftnt/should_you...

Now if you’re ONLY serving high density and high passenger volume times, buses are incredible.

Robotbeat··on Growing proof that autonomous cars save lives
That’s a really difficult problem to solve with the built environment being the way it is. Buses get the closest, but to make it usable at times other than rush hour, they have to run empty or nearly empty, which drives the cost very high (although this is often hidden by subsidies). The way to deal with low density transit is automation.
Robotbeat··on Growing proof that autonomous cars save lives
I believe Tesla’s FSD is already better than such unassisted drivers. Particularly with the current FSD limitations which require monitoring driver attentiveness. If every drunk who attempted to drive was using FSD, deaths due to drunk driving would be virtually eliminated. Heck, even advanced lane keeping and smart cruise control from other manufacturers, while much more crude, would still help tremendously.
Robotbeat··on Stopping the Unstoppable: When an unstoppable force meets a dashpot snubber
Unions.
Robotbeat··on Private German rocket makes history, reaches orbit from European soil
This is an inaccurate simplification
Robotbeat··on Private German rocket makes history, reaches orbit from European soil
French Guyana is part of the EU, actually, in spite of being in South America. (Colonialism!)
Robotbeat··on Uber shuts operations in Nigeria and Uganda with immediate effect
In Nigeria: Lithium totally irrelevant compared to oil. I think people have this really weird idea that lithium is to electric cars as oil is to regular cars, but it’s literally like a factor of 50 less.
Robotbeat··on The Gargantuan Lie That Is Collapsing the Climate
I mean, in the real world, people will just vote out politicians who raise their gas prices.
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