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Comment Re:Because the laser would be all burninaty (Score 1) 83

The difference is the size of the spot on the back of your eye. Sunlight is spatially incoherent, and forms an image on the back of your eye, spreading out the light over that image. A laser is spatially coherent, so all of the light will get focused down to a very small spot, so a much higher irradiance. A (visible) 1-Watt laser will *immediately* burn a blind spot on your eye. Mid IR light is "eye safe" though, so you could withstand up to ~1 Watt (very ballpark, didn't look it up just now).

Comment Re:"...lasers have been thought of as white-hot... (Score 1) 169

Yes, but they aren't only exchanging radiation with each other. The Earth and Sun are constantly radiating to outer space, and would eventually assume the same temperature as the CMBR. If you set up a system that was only exchanging radiation with the Sun, and otherwise completely isolated, it would assume the temperature of the Sun. And there is no way you could possibly get hotter than that (via thermal coupling to the Sun).

Comment Re:"...lasers have been thought of as white-hot... (Score 1) 169

I don't think I agree with that. Let's say we have one system that is held at a fixed temperature, and another system that is isolated, other than a radiative connection to the first. Looking only at this second system, the only interaction it has is through this radiation field. It eventually assumes the same temperature as the first system. However, it's only "seeing" the radiation field. Therefore it's the radiation field that has that temperature.

Comment Re:"...lasers have been thought of as white-hot... (Score 1) 169

You are also wrong! Blackbody radiation, for example, certainly has a temperature associated with it. I'm actually not sure how to think of the temperature of a laser (and I have put some thought towards it, and am studying in quantum optics in grad school). Even a weak laser can heat up a physical object, so it is quite hot. It comes from a lasing material that is at a negative temperature, so it could also have negative temperature. But as another poster pointed out, it has very low entropy. This leads me to think that a laser has negative zero temperature.

Comment Re:Don't think PC (Score 2, Informative) 112

A quantum computer able to do useful classical computing (i.e., factoring large numbers) would have to have a large number of bits (512-1024, very far away by any metric). A quantum computer able to do simulations of quantum systems beyond what current supercomputers could do would have to have maybe 10 bits (maybe not too far away).

Comment Re:what a stupid situation (Score 1) 206

They aren't (mainly) fighting for resources. They're fighting for prestige/career advancement (one of the advantages of which is is easier access to funding). Scientists aren't these abstract, disconnected, altruistic beings you imagine. They seek personal advancement like everyone else, and there's nothing wrong with that when it's done in the proper manner.

Comment Re:God Schmod, I want my monkeyman! (Score 1) 481

There is an important distinction, if you consider the beam going in your eye. The laser beam is spatially coherent, while sunlight is not. That means that when you look at the sun, not all of the light focuses to the same spot (i.e., an image of the sun is projected on your eye). If you were to look at this laser beam, the light would get focused down to a very small spot, only a few photoreceptors wide. This adds another (pulled out of thin air) ~1000x brighter.

Comment Re:So? (Score 1) 691

I very much expect the government to exert maximum legal pressure...

Certainly, so do I. But this was not legal pressure. There was no law saying BP had to do this, or would have to do something like it. I believe in the rule of law, not the rule of man. If you do as well, you should condemn this. If you don't, then you believe in mob rule, not a Constitutional republic.

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