Difference between revisions of "Talk:2516: Hubble Tension"

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(Missing joke about the "slowness" of 85mph/kph)
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I think we've missed an important joke in the last panel. Dave says the galaxies are moving at 85mph/kph and "booking it". However, KM/S/Mpc is going to be on the scale of several thousand times faster than 85mph/kph. Dave's reference to "booking it" is actually moving quite slow. [[User:Pconwell|Pconwell]] ([[User talk:Pconwell|talk]]) 12:57, 16 September 2021 (UTC)
 
I think we've missed an important joke in the last panel. Dave says the galaxies are moving at 85mph/kph and "booking it". However, KM/S/Mpc is going to be on the scale of several thousand times faster than 85mph/kph. Dave's reference to "booking it" is actually moving quite slow. [[User:Pconwell|Pconwell]] ([[User talk:Pconwell|talk]]) 12:57, 16 September 2021 (UTC)
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How is the expansion rate different from an acceleration? The (correct) units surprise me. [[Special:Contributions/172.70.130.87|172.70.130.87]] 14:15, 16 September 2021 (UTC)

Revision as of 14:15, 16 September 2021

Having noticed that 85 KPH is slower than 85 MPH, it took me a while to work out that 85 MPH is much slower than 68 km/s (and I was blindly assuming that the universe is at least one megaparsec in radius), after which the title-text joke started making sense. Congratulations on being almost too subtle for me.00:46, 16 September 2021 (UTC)

Is the 85 mph number significant in any way? Why does "Dave" who points radar guns in random directions get this number? 108.162.245.167 03:41, 16 September 2021 (UTC)

Well, it's probably over the speed limit in most places. Maybe Dave is a traffic cop? --172.68.129.137 04:55, 16 September 2021 (UTC)

Unfortunately, the explanation only explains the things everyone can read on the internet anyway. 85 mph or 85 km/h have the wrong unit, because for the expansion speed we need to look at two points of space, measure how fast they move away from each other. Obviously this should be a number that increases linearly with the distance of the two points (if space is created equally everywhere in the universe). Thus the 85 km/h misses the length. Is the joke here that a random dudes results are reported equally (false equivalence)? --162.158.93.142 04:41, 16 September 2021 (UTC)

Dave again: "But when they hit 88 mph, we're gonna see some REALLY weird shit!" RAGBRAIvet (talk) 06:50, 16 September 2021 (UTC)

Just a thought: maybe Dave is talking about Fords Galaxies? -- 162.158.183.222 08:39, 16 September 2021 (UTC)

I had already added that before I saw your comment. --Kynde (talk) 10:37, 16 September 2021 (UTC)

Relating (coincidentally) with several of the above comments, I added in a "what Dave could be measuring" paragraph (ultimately: just traffic!), via a diversion where I totally messed up a factor and it sent me down a rabbithole of completely the wrong distance! ((Sanity-check my new figures, please: e.g. 85mph => ~0.038km/s => ~0.0005588(of the 68km/s/Mpc figure) => therefore 558.8pc, etc and onwards)) Anyway, perhaps Dave just is/wants to be a traffic-cop? (If you can find humour in the 'all directions' - presumably away from - then obviously supercede the 'both directions' bit.) 172.70.134.47 09:16, 16 September 2021 (UTC)

I believe a radar speed gun pointed at the sky would actually display something like "no reading" when it doesn't receive any radar echo, rather than 85 miles/h. It wouldn't do to fine drivers for speeding when the measurement fails. 162.158.183.208 09:39, 16 September 2021 (UTC)

Dave is measuring Ford Galaxies that are all speeding away from him, either way too fast, or if kph just moderately speed for a normal road between cities. --Kynde (talk) 10:37, 16 September 2021 (UTC)
Unless it is actual some kind of a Ford MPV Owners' Club 'burn out' session of some kind, I read it as more general "large, relatively unwieldy family-style vehicle passing in conspicuous quantities and not actually holding up the rest of the traffic" rather than truly committing traffic violations (in excess of any other vehicle on the road). To "book it" is to hurry, but (more colloquial understandings allowing) more as in the "not dawdling" sense. (They'd be noteworthy only for narrative punning reasons, really, as one of the comic's hooks. But that's only meta.)
Though (outwith the most obviously speed-trapped areas) my personal experience is indeed that driving at the posted speed limit often means being treated as an inconvenient mobile-roadblock, by more than half the rest of the vehicles that come up behind and tailgate or pass, I would still consider hugging-the-limit (whatever it is) as going fast and not actually slow. 162.158.159.11 12:49, 16 September 2021 (UTC)

I think we've missed an important joke in the last panel. Dave says the galaxies are moving at 85mph/kph and "booking it". However, KM/S/Mpc is going to be on the scale of several thousand times faster than 85mph/kph. Dave's reference to "booking it" is actually moving quite slow. Pconwell (talk) 12:57, 16 September 2021 (UTC)

How is the expansion rate different from an acceleration? The (correct) units surprise me. 172.70.130.87 14:15, 16 September 2021 (UTC)