Actually, meters per meter makes sense in a variety of circumstances. If I’m traveling north and you’re traveling west at the same speed, the distance between us in meters increases by 1.41 meters per meter I’ve traveled. If a square with a fixed area is squeezed, the length increases by A/w^2 meters per meter of squeezing. For every meter than the equator moves (as the earth rotates), the city of London moves by about 0.62 meters (.62 meters/meters). Of course the “meters” part is arbitrary - it could be any unit of length, but it’s always length/length.
This thread is very interesting to me but also way over my head. The OP posed a good question.
Does light travel? It has a measurable velocity so it must right?
At the risk of showing my extreme ignorance of the subject of light can I ask a couple of questions?
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Is there such a thing as an individual photon?
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Suppose a flashlight is floating “motionless” in space and it has a torque free on switch. If it is turned on would the photons leaving cause the flashlight to move backwards? (Similar time a gun’s recoil)
Yes and yes. Individual photons can be created and photons carry momentum and so can cause recoil.
Thank you.
So does momentum act as mass? I was expecting the answer to be no as photons have mass.
Photons have no mass (meaning what physicists used to call “rest mass” but now prefer to just call “mass”), but have momentum proportional to their energy (momentum for a photon = Energy times speed of light (P=Ec)).
Andy L already answered, “yes and yes” which is correct.
See double slit experiment for examples of us shooting single photons and getting…weird results.
See solar sails as a use of using light to push a spacecraft (and it would push your flashlight…only ever so slightly but assuming a very long lasting battery the effects add up over time and you would see it move).
As for my post know that as you go faster length in the direction of travel contracts. Time slows down as you go faster and the distance between you and your destination gets shorter. At light speed time stops and distance contracts to zero.
So, to a photon, it goes nowhere in zero time.
Mass is zero, but the photon has momentum, which results in stress-energy hence spacetime bending, etc.
Ok, but photons indisputably take paths through space-time, and these paths have well-defined lengths. And the particles move at the speed of light 
From you sitting there watching them…yeah.
But again, from the photon’s perspective there is no time and no distance. Your room and the universe are the same to it.
We can get close to seeing this in action. Of course, we can never get to light speed but we can imagine it getting pretty close and see how this works:
Agreed that if a photon is emitted in Andromeda, and is observed here, the space/time interval between these events is zero. But, that does not mean that we are in Andromeda (although, as you say, if you go fast enough relative to Earth, Andromeda is not very far at all). The only thing you can’t do is go so fast that the light seems to stay put (or even slow down).
ETA since the light travels a path of length 0 (= 0 time!), that is one way to look at it, yes…
Since time does not pass for a photon, doesn’t that mean that a single photon can be everywhere simultaneously and that maybe there’s only one photon in the entire universe? I know that a single-electron universe was considered by Wheeler. Could a similar line of reasoning apply to a photon?
Part of the one-electron universe is the idea that positrons (anti-electrons) are electrons moving back in time. Since there is no distinct anti-photon, that idea might not work. Or it might work just as well. It’s kind of a bizarre theory anyway.
Anti-photons! So that’s what all the dark matter is.
Key word there: There is no distinct anti-photon. That’s not because there are no anti-photons, just because they aren’t distinct. An anti-photon is the same thing as a photon.
What happens when a neutron meets an anti-neutron?
Neutrons and anti-neutrons are distinct: They have the same charge, but charge isn’t all that matters. And so when they meet, there’s an energetic event that initially releases three pions, which in turn eventually (in a fairly short time) decay into some combination of photons and neutrinos. Note that it’s not quite the same as an electron and positron (anti-electron), which go straight to photons, because neutrons are more complicated particles, composed of quarks, and subject to the strong interaction in addition to electromagnetism.
How can any kind of object have no mass?
Why should it have mass?
It isn’t an easy question.
Thanks for the explanation, it was interesting.
One more question, though.
How energetic is that event? Exceeding nuclear fusion style events, particle for particle reaction? Or tamer than that?
Not that I have anything nefarious in mind, of course. 
Light is a wave. A wave is a type of motion. You can’t have a wave without motion. Things that are moving travel.