Things react to the presence of gravity fields because they have mass. Do wormholes, or the mouths of wormholes, have mass?
Ok, I give. What happens if C continues to slow down? To the point of, say… 99.9%?
Then the expansion appears to accelerate even more. It takes longer for the signals to get to us, so it appears like the galaxies are farther away than they ‘should’ be…ergo they appear to be accelerating.
( since D=rt…if the rate, light speed goes down, and we assume it is constant, then we falsely assign a larger D than actually exists.)
Isn’t negative energy one of the theories put forth to explain the acceleration of the expanding universe?
If the acceleration is really just an optical illusion, then that is that much less proof that negative energy exists I suppose.
I believe quantum mechanics predicts wormholes down at the ‘quantum foam’ level. But I don’t remember where I was reading about it.
So to get a macroscopic wormhole, you’d need to somehow enlarge the wormhole by an insane amount.
Nobody’s tackled my paradox yet! Of course, you need to make a lot of assumptions before you get to the conditions that create the paradox.
False. Light has no mass, but its path is altered by gravity. Basic general relativity.
This (the link) is some of the goofiest stuff and worst science I’ve ever seen.
A quick look at the data in the article would suggest that the speed dropoff is faster as you go back in history and then slows down in the last century. That’s just plain bizarre, and there’s a more simple explanation: the measurements were wrong.
A similar graph exists for the charge on an electron. After it was first measured, later measurements got higher and higher at a slower rate until we reached the accepted value of today. Was the charge on the electron increasing? No, it was simply erroneous. When a new measurement was made, those who published were aware of the previously measured value, and simply didn’t publish the highest values they measured assuming they were wrong.
False. Light has no “rest mass”, but it has a momentum 4-vector. Mass-energy is an artifact of the coordinate system in use and only the tangent covector (a geometric object) enters the equations. That is basic GR.
Wormholes probably do have mass, but that’s not necessary for them to be affected by gravity. Everything is affected by gravity.
Negative energy (at least, of the sort necessary to stabilize a wormhole) has never been observed, and it’s not even actually predicted by theory like magnetic monopoles are (as my advisor puts it, it’s certain that monopoles exist, but there may be only a very small number of them, like zero). Discussions of negative energy are more along the lines of “Well, we don’t know if this stuff exists or can exist, but if it does, this is how it would behave”. It’s not the same as the stuff that’s driving the accelerating expansion of the Universe: That’s dark energy, which is certainly weird, but not quite that weird. Dark energy has a negative (and very strong) pressure, but still a positive energy density. Gravity is actually generated both by energy density and by pressure, though the latter is usually relatively insignificant, so the negative pressure can cause gravitational effects.
As for speculation that the speed of light varies, it’s very difficult to quantify that. By comparison with what do you measure the speed? The usual standard of speed is c, but by that standard, of course, the speed of light has not and cannot change. In order to say that the speed of light is changing, you would need to construct some other speed from constants of physics, and what you actually end up saying is something along the lines of “the ratio of Planck’s mass to the mass of the proton has changed”. But even then, is it Planck’s mass that’s changing, or the mass of the proton? And even if it’s Planck’s mass, does that mean that c is changing, or that hbar or G is changing?
I seem to remember reading that some astronomical observations suggested the fine structure constant had changed slightly from some number of billions of years ago to the present. Since the easiest way to vary the fine structure constant is to vary c, many VLS theorists took this to be evidence their theories were correct.
However, subsequent observations of the same astronomical phenomena that first brought the constancy of alpha into question appear to have refuted the earlier observations. There’s apparently no good observed evidence presently that c has changed.
I’ve read the OP’s billiard ball scenerio over and over and over and over. And over. I think I get it. What I don’t get is how it resolves the grandfather paradox. Sure, it works for certain very specific arrangements of billiard balls; but how the heck does it work if I go back in time and kill my grandfather?