What would the properties of an infinitely long wavelength of light be? And what about a wavelength of light that is infinitely short? What would that look like?
edit: light as in electromagnetic waves, not visible light. Sorry if it was not very clear
There is no upper limit, so really this comes down to how big the universe is.
It’s properties would be that it’s extremely low energy … and basically impossible to detected as you’d need a universe-sized antenna.
For short wavelengths you’ll eventually concentrate so much energy in one spot that it will form a black hole. So that would be the lower limit.
The idea that a very small wavelength would cause a black hole doesn’t really make sense to me since I thought a black hole requires mass. I’m no physicist, so I don’t really know.
However, a search about light with a Planck wavelength came up with this result which seems to claim that eventually the wavelength would become so small as to no longer be capable of holding information and would essentially do nothing.
What the two other replies have neglected to mention as the cool side-effect of light affecting the curvature of spacetime despite being massless is that it’s theoretically possible to make a black hole out of nothing but light. The concept is called a “Kugelblitz”, https://en.wikipedia.org/wiki/Kugelblitz_(astrophysics)
It’s mass OR energy.
Light, even though massless will still bend (and be affected by distorted) spacetime because it has energy in form of momentum. (See: gravitational lensing).
It is affected by gravity. But does it have gravitational pull? The thing about black holes is that they have a lot gravitational pull.
I’m asking because I honestly don’t know.
They do indeed. It’s totally minuscule of course.
Everything that has energy deforms spacetime and spacetime affects how anything with energy moves.
Mass and energy are basically the same thing though. Since
E = mc²you can substitute mass in any equation withE / c².Interesting, I learned something new today :D
How would you create the infinite wavelength? Would you redshift a light source for eternity? Would you have to move it at the speed of light?
Infinities are generally outside of practical applications, so you wouldn’t. It’s more of a thought experiment.
this is actually one of the most fascinating things I’ve read in awhile, thank you.
Why would it be the limit? Couldn’t you keep stuffing more and more energy and get a bigger black hole? Also would such a blackhole move at the speed of light?
I guess. But it wouldn’t be light with a wave length anymore. It would be a black hole.
That’s an interesting thought. I don’t think so. Once you get the black hole it should gain mass. But that’s really hitting the limit of my physics knowledge.
Nothing that has non-zero mass can move at the speed of light so no
I’d say we have set an artificial limit: at some frequency/wavelength, we do not call it “light” anymore. Around 1mm, we call it “Radar” or “microwaves”, and at about 1 m or more, we call it “radio”.
Unless you specifically say “visible light” I assume “light” to just mean electromagnetic radiation.
Otherwise, the answer would be trivial, about 800 nm.