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Why do you always put an apostrophe in the word "does"?

As soon as you bring rockets into it, you're really talking about something quite different to the apparent motion of galaxies due to expansion. Please stop mixing your metaphors; please be more precise.

You sneaky sneaky thing, you! Don't you remember:

Mass is one of the factors in terminal velocity. So the weighted ball will get faster than the unweighted ball. (Been trying to find a good worked example. For a start: https://en.wikipedia.org/wiki/Terminal_velocity#Derivation_for_terminal_velocity )

Not when dropped in air. Air causes drag. Drag is a force. The different masses of the pin pong ball and ping pong ball full of water then makes a difference. ( Extreme example: a parachutist vs a parachutist whose chute didn't open - same mass, different rate of fall. Of course, the two ping pong balls have the same shape, but ... ) https://www.quora.com/If-we-drop-different-weights-from-same-height-which-will-fall-first-to-ground

( ...and on the Moon: )

You keep saying that.

No. If expansion gave actual-moving-through-space-speed, the furthest galaxies wouldn't be receding faster than light, as we know velocities don't add that way. Metric expansion of space is different.

Just to illustrate metric expansion. Say these letters are galaxies and the hyphens are the space between them: A-B-C-D-E-F-G-H-I-J-K-L-M Note that M is 12 x "-" away from A. After some time, space has expanded: A---B---C---D---E---F---G---H---I---J---K---L---M Now, M is 36 x "-" away from A. That seems a lot: | . . . . . . | A-B-C-D-E-F-G-H-I-J-K-L-M | A---B---C---D---E---F---G---H---I---J---K---L---M ... from the point of view of A, M is now (apparently) "moving" very fast (it moves 18 hyphens in one unit of time). But perspective, or point of view, is still relevant here. Take the view from L: |.| A-B-C-D-E-F-G-H-I-J-K-L-M | A---B---C---D---E---F---G---H---I---J---K---L---M ... not such a big deal, according to L, M moves 2 hyphens in one unit of time; that's a lot less than 18 ... there's no point being incredulous about that (apparent) "speed" of 18 from the point of view of A. As to why/how the Universe is expanding, that's a topic that deserves its own thread.

Multiple experiments that give results that match expectation, yet are waved away by claims of somehow all having the same "error" (that yet gives that expected result). It's clear who is operating on belief, instead of science.

May be a good time for this: "What is the experimental basis of Special Relativity?" http://www.edu-observatory.org/physics-faq/Relativity/SR/experiments.html (Hope I'm not repeating earlier use.)

By that reasoning you may as well call astrology and homeopathy "scientific". Or in other words, why subvert a thread by trying to redefine the topic?

Yeah, it all comes down to the funding.

My favourite bit in the blog was "(picture not ready yet (my markers are dried up. I have to go out and buy some more - picture coming soon!)".

There certainly were times when certain things * occurred (or started, or stopped) when everything was closer together than it is now. That's a kind of "nearer". But be sure that doesn't mean nearer a central location; everything was closer to everything else (i.e. I am not contradicting imatfaal). (* e.g. inflationary period)

If your left eyeball is taken as the centre, then your right eyeball is closer to the centre than either of my eyeballs. If Alpha Centauri A is taken as the centre, then Proxima Centauri is closer to the centre than Aldebaran.

Some of that's covered in the linked Universe Today article. (I'd suggest looking into inflation also, for a period of faster expansion. https://en.wikipedia.org/wiki/Inflation_(cosmology)) The rest is perhaps a bit speculative, and maybe deserves a thread of its own.

It's a very sad "technique" to ask oversimplified questions and try to "trap" people into simple answers looking for a "gotcha". Current science is very clear. e.g. https://www.universetoday.com/122768/how-are-galaxies-moving-away-faster-than-light/ i.e. Nothing is moving through space faster than c, but, due to expansion of the Universe very distant objects are getting further away, faster than c. This answer has not changed since the first five times you asked it.

He could aim to stop by hitting the stronger central part of the building - i.e. where the lifts are. Maybe there'd be some secondary benefit or peril - damage to lifts holds off security? Or removes an escape route?

I think you're missing what "dimension" means. It doesn't mean "value". Follow that link you quoted out of wikipedia. e.g. note that the speed of a car might be measured in km/h (or mph) regardless of whether it's going away from you or coming towards you.

(edit: On second thought, best to step aside a while.)

I generally think that a kind of "entry exam" for forums is the ability to properly use them. * changing font for no good reason (sizes, colours, and type faces). * inability to figure out how to use quotes. * inability to use functions like "report". These (singly or in combination) all say something about a poster.

True. Or false. Definitely one or the other. Maybe.

It's all about proper definition. I no longer have any weeds; just an ugly garden. Science!

Very briefly (I don't want to distract from post #176; you should read the post by Janus, again and again). No, you're not getting the answer you want. Time dilation? Length contraction? Relativity of simultaneity? What absolutes? The departure speed between A and C is 1.2 c according to B; but don't (again) confuse that with anyone actually moving at 1.2 c; B sees the distance between A and C grow at 1.2 c; but since B does not consider A as stationary, B does not consider C as moving at 1.2 c (and vice versa). Sure. (But be sure that the speeds, time and distance are all as measured by B.) And time! Close enough; see above. (Not "speed", "departure speed"). Actually not quite so easy. Who is measuring the time? Is t1 according to C the same as t1 according to B? As with your insistence that there are absolutes, you're expecting some "God's eye view" where there's one "real" truth. There's no such thing. Relativity is the opposite of "absolutivity". All this time and you've never heard of length contraction? See post #172 by imatfaal. Day to day life doesn't prepare us to intuitively understand this stuff. People learning relativity often talk of "logic" or "common sense". Of course 1 + 1 = 2 ! Sorry, it's not that easy. Please read post #176 by Janus again.