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Comment Re:Let's clarify some things (Score 1) 42

I can't force anyone to answer questions they don't want to. Also, we gave him every single question that were asked by users that were worded civilly. If the question was extremely toxic and rude we didn't give it to him. Why would someone who is taking out time to answer questions respond to people rudely insulting him? If you can get an inventor like DHH to answer some questions that are worded extremely toxically, let me know and I'll post it here.

Comment Re:points of interest (Score 1) 361

> Its probably the least efficient use of electricity ever invented actually.

Well, except that even this experiment is seeing a thrust-to-power ratio almost 400x larger than photon rockets. So, if it's proven to be a real effect then it has great potential in space, where the benefits of a lack of a gas tank are hard to overstate.

Moreover others, including but not limited to the original inventor, are already claiming to have achieved thrust ratios several orders of magnitude larger, getting into the range of ion drives. If *that* is true then they start looking really attractive. And if his power-scaling theory is correct (yes, even I'm smelling a lot of "if" coming off this conjecture) then they have the promise to scale considerably further, eventually even to the point of becoming a viable alternative to jet engines and the like.

Basically - at present we're working to verify the presence of an anomalous phenomenon. If verified, then it's hard to estimate what might come of it. What became quantum mechanics was once regarded as nothing more than a cluster of unexplained but largely unimportant anomalies. Now it powers awesomely powerful pocket computers far beyond anything imagined at the time. (And that doesn't even touch on any of the really interesting properties)

Comment Re:Vs. Ion Drive [Re:points of interest] (Score 1) 361

Unfortunately it doesn't work that way - the first 1% of reaction mass has to accelerate not only the ship, but also the other 99% of the reaction mass being carried. So as you add additional reaction mass every additional bit gives you less of a speed boost that the one before it. The final result being that if you graphed top speed versus amount of reaction mass, you get something looking like a logarithmic function that rapidly levels off. Theoretically there's no upper limit, but quite rapidly you reach the point where you're having to add multiple solar masses worth of fuel to get an extra few mph to your top speed.

Ion drives are a huge improvement over chemical rockets, but basically you're changing the multiplier in front of an exponential function. It has a dramatic difference at the low end, but pretty quickly the exponential part becomes so huge that a factor of even a few thousand gets lost in the noise.

On the plus side, ion drives promise to be quite suitable for travel within our solar system. With sufficiently powerful thrusters and reactors power them we could conceivably get to Neptune and back in a few weeks. They're just not suitable for crossing interstellar distances on human timescales.

Comment Re:Let's clarify some things (Score 2) 42

I'm gonna weigh in here. Normally I don't react to trolls in the comments because I'd rather the comments stay on topic about the story. I read every story and the vast majority of comments as my time allows. I rarely ever downmod, as other users usually do a good job. I think you're a bit confused if you think someone telling me to commit suicide is "constructive criticism". Judging by your past comments you're just a troll, and hey, that's fine. This isn't Reddit, we're not going to ban you. People can accuse of us "blatant slashvertisements" as the OP here does constantly, but the fact is we have never been paid for a story. There's no way to prove that, but its the truth so if you want to keep accusing us of that, you can, if it makes you feel good rather than just scrolling past the story and reading one that interests you. Again, we're not going to ban you. If you get downmodded for other users, perhaps its because you consistently post things people don't want to read instead of posting a thoughtful comment about the topic at hand.

The fact is the world of technology is a lot larger and more broad than it was when Slashdot was started years ago, so we cover more topics. There are more nerdy topics now than ever. If you wanted to improve Slashdot you'd email your feedback to us rather than starting flame wars in the comments. I assure you I read and consider every email I get. This will probably fall on deaf ears to trolls, but I thought I'd weigh in in case any cooler heads are reading and interested in what I have to say.

Comment No such thing as a scientific proof. (Score 1) 361

There is no such thing as a proven scientific law. Proofs are for mathematics - i.e. conceptual worlds entirely bound by laws of our own creation.

Scientific laws are simply iteratively improved models of an unknown reality that have thus far failed to be disproven despite many qualified people attempting to do so until the consensus emerges that they are valid. And often they're not even that - Newton's Laws have been disproven yet are still honored as laws because they are easy to work with and, for most things within the realm of human experience, they hold true to the limits of our ability to measure, despite the fact that we now know they are only a special case of a far more complicated relativistic model.

Furthermore we know with certainty that our current laws are flawed - for example both General Relativity and Quantum Mechanics cannot be true as they require conflicting values for the vacuum energy constant, implying that one or both models are flawed. And I could give you a list of well-documented phenomena that are unexplained by currently accepted scientific law, implying that either the existing laws are flawed, or their are further laws that we have not yet discovered.

Comment Check your efficiency (Score 1) 361

>Except that we already have engines which are *more* efficient: photonic drives

Not hardly. If that were the case nobody would care aside from physicists searching for new physics.

Wikipedia says the maximum thrust for a perfectly collimated nuclear photon drive is 300MW/N

and that NASA did done laser-thruster experiments last year reaching 500kW/3.5mN = 142MW/N
  - over twice as efficient, I assume because it was a (possibly recycling) "light-sail" design with an external laser, and thus gains twice the momentum per photon (more if they're recycled)

Meanwhile according to the article, the EagleWorks EmDrive experiment claims 1kW/1.2mN = 0.8MW/N
Or almost 400x more efficient than a perfectly collimated photon drive.

And the inventor claims to have improved the ratio by orders of magnitude beyond what's generated by the crude prototype EagleWorks is testing.

Comment Re:I hate Apple, but no (Score 1) 508

>For one thing, the government absolutely has the authority to tell a corporation "yes, these are the taxes that you owe".

Except, clearly, they do not. Ireland is not a wholly independent nation, but a member of the EU, and is governed by EU laws even within its own borders.

A better analogy might be Apple negotiating a tax break or other incentive with a US state that is illegal according to federal law. When caught, Apple would not simply be allowed to keep their ill-gotten gains - they are bound by federal law and it is their responsibility to make sure they are in compliance with those laws. A state government does not have the authority to waive them.

Comment Re:Phase 2 testing (Score 1) 175

Actually, Everest or Antartica would be far colder for most practical purposes. Yes, Mars is technically much colder, but the air is thinner than the insulation in a vacuum thermos, so there's essentially zero thermal transfer except into the ground, which is easy enough to insulate against. Go exert yourself outside in an uninsulated (except for the soles of your feet) pressure suit, and just like in an orbital EVA overheating will be your problem, not the cold.

Comment Re: Only SOME Optical Media Is Durable (Score 1) 382

True, windows don't block 100% of UV, but they're usually in the high 99% range. Bleaching though - I don't think that's specifically a UV effect. Surprising that it wasn't an issue with the disks.

I stand by my luck assertion though - I've lost data from discs of most every brand over the years, as have most people I know. Some people just get lucky with such things. Me, I've only had two hard drives die on me in the last 30 years - and I'm still using drives from 15+ years ago, which also seems very unusual. Hey, the world is a big place. Statistical anomalies abound.

Comment Re: Only SOME Optical Media Is Durable (Score 1) 382

Rear deck... the shelf behind the rear seats? Then they almost certainly weren't in direct sunlight, though they may have been heated nicely. Modern car windshields are pretty much universally designed to block UV rays, the high-energy wavelengths that cause most damage. Without that protection most of the plastic interior of the car would rapidly become brittle and crumbly within a few years, photodegradation is a major problem for plastics.

Still, you probably also got very lucky if you truly had no problems.

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