He wrote that 5 years ago, but the pixels just arrived now.
This is, of course, completely wrong. There is no “point where the Big Bang took place” and we can’t be “off to one side.” Nothing can. The Big Bang took place everywhere, all at once. Every point was “inside” the Big Bang.
Relativity restricts the speed of anything moving in space. It does not restrict the space expansion effects.
on edit: I gotta check dates before responding.
It’s not that things are going, it’s that there is changing?
Distance and time are the same thing, light is constant in speed, and gravitational time dilation has nothing to do with this question. Just so the record is clear.
Almost. I’d say it isn’t that things are going, but that between is changing.
I was waiting for this.
Chronos, how do avoid using up a lifetime quota of :smack:'s?
Your allotment for me alone must be running dry.
I don’t view such statements as :smack: moments, but as teaching opportunities, especially in a public forum such as this. I might or might not get through to the poster of the original comment (often, such a poster never returns to the thread), but I can get through to many other people.
In the ideal case, the poster of the original statement does return, and explains why they thought what they did, which allows me or other knowledgeable posters to get at the root of the misconception.
I am a tree of misconceptions, my roots are many.
eta: and I love your posts - I usually don’t respond to them or ask many quesitons about them, but I do watch for them and read them. Bravo for the many years of contributions since I haven’t bothered to thank you previously.
Of course. I felt bad immediately after I posted it.
It reads absolutely like a combo :rolleyes::dubious: post directed at the OP content, and by implication OP as a person. That this sentiment is wrong for any GQ post, which fights ignorance, is the Board’s primal strength. One poster’s obviousness is always some other’s ignorance, and we self-select to respond to that.
It’s that, In my experience here, for example, some questions of music theory or history are so huge, mixing detail with philosophy (not unlike May in TS Eliot’s calendar), that even to begin to respond with pedagogical intent seems, and often is, unworkable.
The only possible response in these cases is to respond factually ex cathedra, which is not my style. A lot of error is on the Internet, even that small segment of SD, and I let it flourish on its own recognizance. Even though occasionally I feel guilty for not contributing some anti-ignorance where I can.
Finally, given the above, and despite its collateral damage, I intended the post to be a compliment directed to you for your constant and decade-long responsibility, responsiveness, and teaching. Except, by reflection, when you’re going mano-a-mano with other physicists, and most of us, myself include, scatter like ants when the elephants are fighting.
Google is your friend.
Gravity can affect light, and time.
Hence, a light-year is a unit of distance, not time. Distance and time are separate, especially when not on earth.
You do realize you’re wiki citing to a professional physicist, right?
Not much of a physicist if wiki can show him up, eh?
Just kidding. I love your stuff Chronos! Always interesting to read.
So, just so I can be clear on this:
Is it like space is the 3-dimensional hypersurface of a 4-dimensional hyperballoon that is in the process of inflating?
That is circumstantial ad hominem. Hopefully Chronos will critique the message rather than the messenger. Thanks for the heads up though.
More on the variable speed of light:
That second article deals with the speed of light through a medium. It’s like how the speed of light is slower through water or glass than it is through air. In these cases, c still has the same value.
What the “variable speed of light” crowd usually means is a hypothetical speeding up or slowing down of the speed of liight in a vacuum. In other words, they’re claiming that c itself has changed with time.
Granted, but space is not a perfect vacuum.
Doesn’t matter in the end, all Wiki physics articles are routed to Chronos’s ISP, where he types out anew text for each Internet search.
I doubt that the density of the interstellar medium results in an index of refraction higher than 1.0000…0001, where “…” is shorthand for “a whole buttload of zeroes”.