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Comment Re:I agree, but not for the same reasons as Musk (Score 1) 80

Congratulations, you have it entirely backwards.

The maximum efficiency of a prop, in newtons per watt, is 1 / (v_wake + v_freestream), where velocity is in meters per second. The faster you're moving (the freestream velocity), the less thrust you get per watt. Which is why large props are more efficient (more air moved at a lower wake speed), particularly at low speeds, and same for high bypass jet engines.

Now, in terms of "energy per 100km" or "miles per unit energy", obviously a hover yields "infinite joules per 100km" and "0 miles per joule", because you're not going anywhere. But that's an entirely different situation than propulsive efficiency. If you want to start factoring in motion, then your cross section / drag coefficient / L:D ratio / altitude (and thus density) and so forth come into play, and the optimum speed comes down to a balance between a wide range of factors - the faster you go, the less time you spend flying, but your drag increases quadratically, and your prop efficiency drops (the rate of drop relative to the difference between the freestream and wake velocities). Airplanes maximize this balancing point by having extremely low drag coefficients (Cd), far less than cars tend to have.

Comment Re:Really? (Score 1) 80

The assumption is that if flying cars were common, there would be vastly more locations. As they basically function like helicopters (in most conceptions - VTOL), they need only something equivalent to a helipad, not an airport. Which is much cheaper and smaller footprint than an airport.

To get to the point of allowing takeoff and landing from, say, a driveway, you'd have to have a long track record of excellent proven safety, and levels of noise reduction that current technology doesn't yet support. It's certainly conceivable in the future, but is anything but a first step for companies working on flying cars today.

I personally view flying cars as pretty much inevitable (although not around the corner) regardless of whether or not they're pursued directly at present. Namely because of delivery drones. Businesses are not going to stop pushing for them because there's such an economic case for them (not having to drive a big truck around city streets, pairing trucks with drones to not have to go down each sidestreet or stop at each location, etc), and they'll advance the technology as needed to get approval - starting small. But economics will continually push them toward making larger and larger models, and the technology to get approval for those. And eventually you'll have models large enough to carry people around, wherein the question will inherently arise, "Why, exactly, aren't they carrying people?"

Comment Re:Really? (Score 1) 80

So your concept is that something statistically likely to crash and injure people would be approved by regulators, rather than manufacturers being forced to prove reliability in real-world usage conditions before being granted approval?

Comment Re:Really? (Score 1) 80

The assumptions involved in your post:

1) Flying cars would be allowed to just take off and land wherever they want.
2) People would be manually piloting them.

I don't know where you're getting your concept of flying cars, but none of the flying car advocates I've ever heard from advocate for either of those things.

Comment Re:The problem with flying cars is... (Score 2) 80

I don't want to think of what they would be like as pilots

Yes, because when people talk about flying cars, they totally mean manual piloting.

I don't even want to consider those traffic jams.

Um...

Waterfall Sr.: Our peace ring has 'em trapped like a tiger in a washing machine!
[The engine of the Planet Express ship flares up.]
Leela: Get ready!
Protestor #1: Look out!
Protestor #2: Hold on!
Waterfall Sr.: Here they come!
[The ship rises up from the middle of the peace ring and tows the tanker over the top of the protestors. It flies away.]
Leela: When you were planning this peace ring, didn't you realise spaceships can move in three dimensions?
Waterfall Sr.: No, I did not.

Comment Re:Well it's easy to show superhuman AI is a myth. (Score 1) 211

in the middle range, 90 - 110 points,

IQ tests are also unreliable at the tail ends, for epistemological reasons.

How do you construct an intelligence test? You start with a collection of reasonable-seeming tests and you have a sample population perform them. You then rank them on test performance and assess whether your ranking confirms your preconceptions. So here's the problem with the tail ends: it's really hard to get a large enough sample of subjects to test the predictive value of your test with people who score three or more standard deviations away from the mean.

So while you can probably make predictions about differences in accomplishments between someone who scores 90 on IQ and someone who scores 110, I don't think you can predict much from a difference in IQ between 150 and 170, other than that people with an IQ of 170 will likely consistently score higher on an IQ test.

Comment Re:Well it's easy to show superhuman AI is a myth. (Score 1) 211

You seem to be confusing the concept of intelligence with *measuring* intelligence.

You know you're right. But I think there's a good reason for this: magnitude is an intrinsic part of the concept. I've never heard anyone talk about intelligence except as a concept that allows you to rank things (e.g. Chimps are more intelligent than dogs, which are more intelligent than gerbils). So to apply it to an entity like a human or a program is to implicitly measure that thing.

What I'm saying is that the concept is useful but of intrinsically limited in precision.

Comment 1,000 quatloos on the newcomer AI? (Score 1) 211

In some regards I'd argue that one deserved an insightful mod. The comment that actually had one (at this time) didn't deserve it, and no "funny" comments at all. Sad. (#PresidentTweety contamination is bigly sad.)

Consider the Fermi Paradox. Obvious resolution is that they're out there, but not talking to us because we're still amusing enough to bet quatloos on. What are they betting on?

Whether we create our AI successors before we exterminate ourselves. Right now the odds are falling fast. (#PresidentTweety again.)

Yeah, I'm speculating, but natural evolution is a kind of random process and follows many paths. There is some convergence, but it's still interesting to watch the various paths. The AIs are NOT coming from random processes and blind watchmakers, but will probably converge on the laws of physics without much of interest to watch. When our AI descendants get to that point, they'll get (and be able to understand) the greetings from the others.

Comment Well it's easy to show superhuman AI is a myth. (Score 3, Insightful) 211

Because intelligence as a single-dimensioned parameter is a myth.

We already of have software with super-human information processing capabilities; and we're constantly adding more kinds of software that outperforms humans in specific tasks. Ultimately we'll have AIs that are as versatile has humans too. But "just as versatile" doesn't mean "good at the same things".

So it's probably true that software is getting smarter at exponential rates (and humans aren't getting smarter as far as I can see), but only in certain ways.

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