I think I read something to that effect. That the most common (majority or plurality) type of electromagnetic radiation in the universe is within the range of what we call visible light. Or was it that the most common to reach Earth? I don’t know where I read it, or I would not be asking the teeming masses for assistance. (or education). Anyone? Beuhler? Beuhler?
I don’t have figures, but I seriously doubt it. Heck, most of the radiation coming from the sun, or from an incandescent light bulb, isn’t visible light. Anything hot is putting out more long-wave energy than visible light. Cosmic background radiation isn’t visible light. The band of visioble wavelengths is a very narrow sliver of the possibvle wavelengths of electromagnetic radiation.
There is, it’s true, a “window” in atmospheric absorption that lets viosible light get through the atmnosphere efficiently, but a lot of other wavelengths get through as well.
That depends on how you’re measuring “most”: By amount of energy, or by number of photons? By number of photons, the cosmic microwave background accounts for the significant majority. But they’re all really low-energy photons.
By total amount of energy, well, it probably still isn’t visible light, since the visible band is pretty narrow. But the peak just might be in that range, since stars mostly peak in that vicinity.
The problem is that when we refer to “light,” we’re talking about light that’s visible to humans. And the fact that the band is “narrow” says more about us than the light.
But that’s the point. Is it true that the majority of radiation in the universe happens to be in the visible light band? That, if true, would be an interesting fact.
Not altogether. After all, we did not just “decide” arbitrarily on that band: we evolved a sensitivity to the band that would be of use to us (and that our basic physiological endowment would be able to handle). If there wasn’t plenty of visible light around in our environment, and if its structure didn’t carry behaviorally useful information (radio wavelengths, for instance, probably wouldn’t) we would not have evolved a sensitivity to it.
Almost certainly not.
Charts like the Hertzsprung-Russell chart give the bolometric luminosity of a star, which includes both visible and invisible light, so it’s hard to make a comparison. But, as I say, the sliver of radiation going into visible light (as opposed to other, mostly infrared light) is pretty small. As the Harvard Spectral Classification chart on this page ( Stellar classification - Wikipedia ) makes clear, about 3/4 of all main sequence stars are light orange-red type M stars, with a luminosity only 0.08 or less that of the sun, with little of their energy going into the visible, but a whopping lot of it in the IR. Another 12% are type K orange stars, with bolometric luminosity 0.6 or less of that of the sun, with most of it in the IR as well. 7.6% are type G, like the sun. Before it hits our atmosphere, 50% of this light is IR, and only 40% is visible light.
Of Main Sequence Stars, then, the vast majority of light is in the infrared, not the visible, or even ultraviolet. Stars hotter than our sun (with higher proportions of visible light) make up less than 4% of stars.
Then, of course, there is possible “dark energy” that we currently have no way to detect. Given that the dark matter theory suggests that most of the matter in the universe is invisible, one could easily infer that the lion’s share of radiant energy in the universe is also beyond even our ability to detect.
In 2004, a couple of cosmologists did a “cosmic energy inventory”. Their conclusion was that of the two types of electromagnetic radiation in the Universe — cosmic microwave vs. stellar — there was more cosmic microwave radiation: about 5 x 10[sup]-5[/sup] of the Universe’s total energy for the cosmic microwave radiation, vs. about 2 x 10[sup]-6[/sup] for radiation of stellar origin. That’s a difference of about a factor of 25. They also claim (with a citation) that electromagnetic radiation from stars is dominated by energy in the optical and near infrared portion of the spectrum.
That paper’s quite a bit to absorb. For reason I give above, I have a hard time believing that visible and even near infrared dominates over all infrared. And even by their own accounting the energy of the “primeval thermal remnant: electromagnetic radiation” (entry 2.1 in Table I) is more than an order of magnitude larger than the contribution from visible and near IR light from stars (entries 7.2 and 7.3 in the same table).
While that is true enough, a more significant driver of the evolution is that the visible wave lengths are those the atmosphere is most transparent to. And really short rays are hard to focus. An X-ray telescope does not use lenses, but a kind of mirror. This also has to do with the transparency of glass and whatever eye lenses are made of to visible light.
I’d appreciate your explaining your opinion on why that fact, if true, would “certainly not” be interesting to me.
I did, above. More than once.
I can see it being “interesting” to creationists who might believe God made visible light most abundant for our convenience.
On the other hand, evolutionists would possibly find it interesting as having an influence on the evolution of sight organs.
Peace.
What’s the scoop on other animals? Do they see infrared or microwave?
Not interested in arguing, but I surely don’t see that. I see you doubt that visible light is the most common, but I don’t see where you explained why that’s not interesting to me.