Now, see, to an American, “torch” means a stick with some pitch and rags wrapped around one end and lit on fire. Or at least something on fire, like a welding torch. I’m pretty sure that it means that in Britain, too, but here, that’s all it means.
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What’s the brightest light in the universe?
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Can it penetrate 30,000 feet of water?
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Quasars are.
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For sure it can. If placed next to the earth, it’d shine through it. Also the rest of the solar system. And by “shine through it”, I mean disintegrate it.
This kind of highlights the fact that there’s an upper limit to the problem: when your water is beyond a certain depth, delivering a visible flux to the bottom layers requires a flux at the top so high that the absorption will simply boil away the upper layers. I don’t know what that limit is, but Dr. Strangelove’s post (#4), with its inconceivably large exponent, suggests that we may already be there; I would guess that a source which is 10[sup]254[/sup] times as intense as the sun would quickly boil away the entire ocean, along with the rest of the planet. For innumerate readers, understand that 10[sup]254[/sup] is a 1 followed by 254 zeroes. This is vastly more than even the number of particles in the universe (about 10^80). A really big quasar is only about 10[sup]14[/sup] times as bright as the sun; while it would indeed shred the solar system as described, you still wouldn’t see it at the bottom of Challenger Deep - at least not until it vaporized most of the ocean.
See also LSLGuy’s post (#30) for a link to an XKCD “what if” piece, which points out the same problem arising from hitting the moon with too much light.
Cite?
I’m typing this as I get ready to leave, so even more shoot from the hip: flux is flux and lumens is lumens.
Is the “brightness”-energy relation a given at every frequency, a black-body principle?
I’m not being (too) facetious here. If you can’t see frequency range x, it sure is dark out. And OP, wanted to see something, goddamnit.
So I’m chasing the subject back to human-in-the-loop…Which frequency light is the brightest (most tolerable) for us to actually see, before we go blind, melt, are disintegrated? I suppose optic nerve conduction and visual cortex processing time (GQ has a bunch on that) must be taken into account.
Does this make sense ( * checks clock sees he’s late closes computer * )?
I might have misquoted Einstein there :).
There is a quote by Albert Allen Bartlett:
The greatest shortcoming of the human race is our inability to understand the exponential function.
It’s always attributed to Einstein, though, because any professor named Albert but obviously be that guy with the funny hair. I figure, as long as we’re going to misquote people, we may as well have fun with it.
Red photons are about half as energetic as violet photons. OTOH, our night vision is most sensitive to green (right in the middle of the visible spectrum) and blue (closer to the violet end), and water absorbs more strongly in green than blue.
So if you can choose the wavelength of your torch, I think blue is what you want in order to minimize your power requirement.
Einstein did say that compounded interest is the most potent force in the Universe, which is a different way of expressing the same sentiment.
I recall reading an SF story set at a time where our solar system was well-colonized and asteroid-based industry was commonplace. The story included a reclusive tycoon who owned and lived on a moon of Jupiter or Saturn.
Speaking about the tycoon, somebody in the story said something along these lines: Beyond a certain point money develops a Schwarzchild radius and begins growing without limit. You simply can’t contrive any way to spend the money that’s already inside the radius. You can only spend the accretion disk which despite your efforts still keeps getting bigger.
Compound interest indeed.
That sounds like the same problem as the human population growth arguments with regards to the speed of light: population grows exponentially, while an expanding sphere of ships/colonies/etc. only grows with R[sup]3[/sup]. You inevitably run out of space, since exponential functions grow faster than any polynomial.