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Comment Re:Self Cleaning (Score 1) 388

Not really. With high power lasers you really should make sure your optics are clean. Not so much for the energy loss of the beam but for damage of the optics. Any dirt on a lens or mirror will partially reflect some light which propagates back into the lens and is eventually being focused therein. For low power lasers this is harmless but when you go to high power this little amount of light is able to form a plasma when focused and hence destroy the optics. Since they try to ignite the gasoline I assume it is a somewhat powerful laser. If it is the optics might be damaged by soot, if not the soot will just stay there and you'll have to remove it manually.

Comment Re:Longer lifetimes is the answer (Score 1) 627

Nitpick... the time dilation for a constant relative velocity is, as the term 'relative velocity' suggests, symmetrical. People on earth see the ships clocks go slower as the crew sees the clocks on earth go slower. Both age at the same rate, that's the Twin Paradoxon of special relativity.
A constant high velocity is not the reason why this works, you have to take the acceleration into account a real ship would have to undergo.

Comment Re:Achem (Score 1) 234

I blindly assume you have not read the pdf either you have linked, or did you? No relation to thermodynamics in it.

Wrong and wrong. Did you read it? The first part is about magnetism in general which is later used to define the partition function of a paramagnet and calculate thermodynamic properties it, i.e. heat capacity or entropy.

In other words: the famous 1st, 2nd and 3rd law of thermodynamics have no relation to magnetic or electric or other fields.

You forgot the 0st law...
Anyway, the laws of thermodynamics only account for the macroscopic features of an ensemble. They define relations between these properties independently of the microscopic nature of the ensemble. But to use this on any real system the microscopic interaction has to be described to derive the first set of macroscopic properties. And this has to include the magnetic or electric forces if present.

Comment Re:Aside from that... that isn't scientific litera (Score 1) 1038

I beg to differ. We do have quite some evidence. The human evolution can be traced back to about 3 million years where the Australopithecine lived. Only after that the Homo genus appeared and its remains could be found. There might still be some links missing and you could give or take a million years due to undiscovered specimens for the first appearance of the Homo genus. But the overall picture is consistent and to assume there have been human ancestors 65 millions back in time together with the dinosaurs is just absurd.

We have a consistent picture of human evolution which starts 60 million years after the dinosaurs became extinct. Of course you might doubt the extinction but for that we have quite some good arguments, too. On the one hand how likely would it be that you find all kinds of skeletons only up to the point of extinction but not afterwards? Unless all remainung dinosaurs gathered together in a yet undiscovered spot on earth this cannot be explained plausibly. But that's not real evidence, granted. At the same time the dinosaurs stopped to exist we also see that remains of many species stopped to appear afterwards, leading to the assumption of global mass extinction. And last but not least an impact crater of a meteor dating back to the very time the assumed extinction took place has been found. All in all this picture is pretty consistent, too.

Comment Re:Achem (Score 1) 234

Like other posters pointed out: you likely don't know what thermodynamics even is. Hint: thermo has something to do with temperature. Thermodynamcs is about entropy and heat not about magnetic fields or electric fields.

Do you? Try googling the next time... some random examples:

Classically thermodynamics was all about heat and temperature and as been developed to accurately describe steam engines. Since then this has evolved and been applied to many other situations. Thermodynamics is about describing macroscopic properties of a large ensemble of particles (this includes photons and such) by their microscopic behaviour. This is not limited to simple mechanical effects like gas molecules bouncing off of each other.

Comment Re:Energy Independence (Score 1) 438

So we agree, coal plants generate more radioactive waste than nuclear plants.

No, that's not true. Coal only contains minor radioactive components that are all around us anyway. In nuclear reactors additional highly active material is produced and other components get activated. But it is completely contained and therefore you can control it much better. In that we agree.

It's been a while since I last did a paper on this stuff, but here's a semi recent link:

From the abstract I guess we talk about different things. Transuranic components are not the waste I talked about. They surely can be used for another fission cycle. But the resulting lighter elements thereafter can not be fissioned in a proper chain reaction for energy production and are thus waste.

Coal plants are just treating the pollution as an externality, that and NIMBY are the only reasons it's "cheaper". We've already agreed the nuclear plant is safer. If you want to talk about "terrorists" or boogey men attacking something, drive past the billion gallon LNG tanks in New Jersey and tell me how dangerous natural gas is first.

Ok, first we do agree that coal plants are worse than nuclear. For the time beeing nuclear is IMHO the only real option of energy production. But that doesn't mean it's an optimal solution. There might not have been accidents for a long time but these things are not completely safe. And the worst case scenario of a nuclear plant accident is way worse than of any other power plant. The only good longterm energy source I see is fusion. Inherently safe and only short-lived radioactive waste.
Second, the nowadays so popular terrorist scare tactics might work well in the US, but not where I live.

Fast breeder reactors were indeed in use 20 years ago, they continue today and that usage is, outside the US, increasing. The so-called security concerns are that the US doesn't want other nations to be able to POSSIBLY make weapons out of that plutonium that is a by-product of using U238.

Well, according to only 4 breeders are operational at the moment, in contrast to >300 non-breeders. The weapon-making-issue is not what I had in mind. Breeders have a way lower power / volume ratio than other types of reactors, making them economically less interesting. This might change however when the Uranium resources deplete. Plus you have in some types liquid sodium as coolant which has to be handled safely, again increasing the costs. Quite sad that higher costs seems to be a stronger argument than a superior technology...

I'd love to see an accessible paper that shows coal is as clean as and still cheaper than nukes that isn't from a loon, including the cost of storing that arsenic, cesium and other "nasty stuff" that goes up the coal plant smokestack, unfiltered, much less recapturing the CO2 in any fashion.

Most coal plants nowadays use filters which get almost anything out except the CO2. Some of the stuff like sulphur oxides can even be turned into useful stuff like plaster. Extracting the CO2 is currently work-in-progess. The costs for both types of energy are almost the same. Give or take a cent, varies from country to country.

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