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Comment Re:Too bad... (Score 3, Insightful) 610

Hmm.. Let's see. The Sun is getting hotter and the last time the concentration of CO2 was as high as it is now was about 20 millions years ago. At that time there were trees growing in Antarctica and the global temperatures were about 8C hotter than now. The seas were at least 30 meters higher.

Oh, and since we're not planning to stop spewing CO2 any time soon, it's possible that we'll get its concentration as high as during the period when dinosaurs roamed the Earth and trees were growing near the poles. Are you sure that such sudden change won't overwhelm natural feedback mechanisms?

Comment Re:Hoax (Score 4, Interesting) 986

I kinda doubt that Einstein knew about Olinto. But relativistic transformations are called Lorentzian for a reason, and Heaviside discovered the relativistic length compression. However, both of them thought that their results were artifacts of calculations and can be made to disappear with a careful selection of a reference frame and/or aether properties.

Then why do we Einstein made the mental leap that nobody before him was able to do - he actually said that the relativistic effects are _real_ and that if you consider them all together then they form a consistent theory. A weird theory where clocks run at different speeds and length and mass are not constant, which is why lots of physicists dismissed it at first.

Comment Re:Hoax (Score 2) 986

We can't really trust the report, given that there are so many variables in play here. Like an unknown heat camera, questionable setup (why no watt-meter to measure the accurate power use??) and interference from the inventor. If I was planning to hoax everybody then I'd bribe one of the investigators to look the other way while I 'calibrate' a biased camera.

So no, I don't think that this merits further investigation unless Rossi provides the clear instructions to prepare the 'fuel' to a third party.

Comment Re:Hoax (Score 2) 986

Monitoring output is surprisingly complicated. They've used heat cameras to watch the temperature of the 'reactor' and from that they calculated the supposed heat output.

Except that it's not so straightforward to do. Emissivity of materials can affect measurements by quite a bit - just look at a thorium lantern mantles or newer rare-earth mantles, they are very bright at fairly low temperatures. I don't see that anybody checked the "reactor" coating materials for rare earth dopants.

Then there's a question of the control experiment - Rossi had set it up himself, to avoid overheating the coils (?). Lots of potential for mischief right there.

Comment Re:please no (Score 1) 423

Just admit that you know jack shit about the subject. In particular, any radiative forcing calculations have to deal with the water vapor which acts to amplify the heating. So it's not a calculation for a piece of paper and 20 minutes anymore.

We also know one important point from linear stability analysis. For the Earth's climate system to be stable at all, it has to respond to perturbations in forcing by opposing the change, not augmenting it.

Or maybe flipping between two extremes? How about that for a "null hypothesis"? Do you know that once there were trees growing in the Antarctic?

Oh, and since we're talking hypothetical shit without any real connection to the actual science, you MUST also mention the possibility of the Venus effect - runaway greenhouse warming. Why do you think it's impossible? After all, the Sun is growing hotter and this time _just_ might be nonlinearly different! If we think about the nonlinear systems then we MUST fail on the side of caution and stop ALL the CO2 emissions NOWNOWNOWNOW!!!!!!!111111



And reality check - we actually do know quite a bit about actual climate processes and we can model them with a significant precision. The models show that the global warming won't be catastrophic for the environment itself, but it'll cause wild upheavals in the human economy.

Comment Re:please no (Score 1) 423

I very much doubt that you've ever seen a spectrograph or have any actual knowledge of physics. The greenhouse effect of CO2 is easily confirmed by simple experiments, in particular.

And what's your crap about the "null hypothesis" and "basic physics" has to do with it?

The Earth is warming. Rising CO2 concentration provides explanation why it happens. Both are facts.

The details of the warming, on the other hand, are extremely complicated.

Comment Re:please no (Score 1) 423

Dude, you're incoherent. Climate models start from one veeeeeeery simple fact: more heat is going in then going out. That's been measured by the satellite albedo measurements and can be directly quantified.

Then we have a direct causative agent - the rising amount of CO2. It's directly measured without any integration or even differentiation needed! So what do you say to that?

No need to invoke Lyapunov or Kolmogorov. Do you think you're the only one here who knows that ODEs are?

Comment Re:The NERVA Project (Score 1) 125

NERVA has poor specific impulse at the sea level. It can work as an engine for launch, but not any better than the classic liquid engines. It's theoretically possible to improve its efficiency by using better reactor design and specific impulses up to 600 seconds are probably possible.

Also think about it - you are flying a freaking high-powered nuclear reactor on a rocket. What if something goes wrong? Well, say 'hello' to your own mini-Chernobyl conveniently delivered into the upper atmosphere!

And once you're in space... You can use VASIMIR or good old ion engines for slow-but-steady high-specific-impulse propulsion. There's no need for high-thrust acceleration.

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