- #5,321
BillTre
Science Advisor
Gold Member
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Even the climate change deniers are starting to wilt away.BillTre said:
Don't bet on it.Ivan Seeking said:Even the climate change deniers are starting to wilt away.
There are still enough around here to get posts on the subject removed or censured.Ivan Seeking said:Even the climate change deniers are starting to wilt away.
I worked very hard for most of my life to try to help avoid this. Now part of me is glad I will die before it gets much worse.
The extended temps of 110 degrees F and greater are starting to get peoples attention. For example, Phoenix has been 110 F or more for I think 25 days now.Borg said:Don't bet on it.
https://www.gocomics.com/tomthedancingbug/2023/07/21
No longer tweets. They are now called "X's"Borg said:I'll agree that I haven't seen as many stories (or tweets) about it being fake but I do have a friend who still belives that the science is all made up because "someone in England, deleted their data". Explaining to him that there are far more than one person researching it, didn't really matter.
Also, no one in England deleted their data, I asked them. We are a tiny little country and I know them all. Trust me.Borg said:I'll agree that I haven't seen as many stories (or tweets) about it being fake but I do have a friend who still belives that the science is all made up because "someone in England, deleted their data". Explaining to him that there are far more than one person researching it, didn't really matter.
Naw. Just wait for record cold temperatures this winter and they'll be back because cold temperatures and global warming can't possibly be related.Ivan Seeking said:Even the climate change deniers are starting to wilt away.
? The hike is dangerous so they are going to unenforceably ban swimming in order to discourage hiking.BillTre said:It was too cold in a local swimming hole (38˚F):
View attachment 329649
that would be:
https://www.kezi.com/news/officials...cle_f7d1ad1c-2b42-11ee-99eb-e7933b44d814.html
That's what it sounds like.Hornbein said:? The hike is dangerous so they are going to unenforceably ban swimming in order to discourage hiking.
gmax137 said:I don't know about Bridge, but in casinos I often see the dealers "washing" the cards, ie, mixing them up the way a kid who can't shuffle would.
Wilt away? Or retire to their private islands now that they've made their money off the lie...Ivan Seeking said:Even the climate change deniers are starting to wilt away.
Through my personal interactions, I have observed a subtle but significant change in how deniers react to this subject. My impression is that their confidence has been shaken.DaveC426913 said:Wilt away? Or retire to their private islands now that they've made their money off the lie...
Which galaxy?Hornbein said:TIL that the largest known galaxy has a diameter of 1,764,000 light years.
ESO 383-76 according to Wikipedia.PeterDonis said:Which galaxy?
To put that into perspective, that's about 20 times the diameter of our own galaxy (again according to Wikipedia).Hornbein said:TIL that the largest known galaxy has a diameter of 1,764,000 light years.
Or over half the distance to AndromedaDrGreg said:To put that into perspective, that's about 20 times the diameter of our own galaxy (again according to Wikipedia).
(Caveat: all these numbers are estimates, and different estimation methods can give substantially different answers, yet again according to Wikipedia -- this is a subject I know nothing about.)
68%!BWV said:Or over half the distance to Andromeda
To put that in perspective...BWV said:Or over half the distance to Andromeda
What is the centripetal force acting on an object on the outermost edge of that galaxy?Hornbein said:TIL that the largest known galaxy has a diameter of 1,764,000 light years.
I should clarify that - despite my deliberate artistic licensing - it's actually an elliptical galaxy.Ivan Seeking said:What is the centripetal force acting on an object on the outermost edge of that galaxy?
I don't know what you're trying to do. Were you trying to use ##a = GM/r^2## ?DaveC426913 said:I should clarify that - despite my deliberate artistic licensing - it's actually an elliptical galaxy.
The force shouldn't be too hard to approximate (by pretending it's of uniform density).
Mass: ##2.3\times 10^{14}## M☉ (230 trillion Sols) = ##4 \times 10^{44}## kg
Distance: 882kly = 8.3x1018km
(I'm doing something wrong; I get like 7x1020Newtons). I'll show my work...
$$ M = 2.3 x 10{14} ~~;~~ D=8.8x10^5 \mbox{light years} $$
(1 light year = 9.4E12 ?what?
They do work if you RTFM. I fixed yours a bit.DaveC426913 said:(OK, I give up on LaTeX or MathJax or whatever it is. The commands they say work don't work.)
If it were a spiral, you should be able to get a reasonable approximation to the outer tangential velocity using the Tully-Fisher/MONDian formula ##v_{\text{tan}}^4 = GM a_0##, where ##a_0## is the Milgrom constant. From that you can calculate centripetal acceleration.Ivan Seeking said:What is the centripetal force acting on an object on the outermost edge of that galaxy?
To be pedantically and relativistically correct, the answer is zero.Ivan Seeking said:What is the centripetal force acting on an object on the outermost edge of that galaxy?
Heh. I doubt we get into velocities great enough or gravity strong enough to require GR. But if the word "force" doesn't apply at all, perhaps it should be dropped altogether. Why are we teaching false physics?DrGreg said:To be pedantically and relativistically correct, the answer is zero.
(Gravity isn't a force in relativity, but of course in Newtonian theory it is a force.)
I was just trying to show my work - one equation per line. I RTFM'd and it said that "\\\" starts a new line but it does not.strangerep said:I don't know what you're trying to do. Were you trying to use ##a = GM/r^2## ?
They do work if you RTFM. I fixed yours a bit.
You need the eqnarray* environment. It's basically a three column table with the columns right, center, and left aligned. Within that environment, & delimits the columns, \\\\ ends rows. Like this:$$\begin{eqnarray*}DaveC426913 said:I was just trying to show my work - one equation per line. I RTFM'd and it said that "\\\" starts a new line but it does not.