Spaceships and astronomy
Jun 16th 2019, 3:57 pm
#316
Thread Starter
Joined: Dec 2001
Location: Dixie, ex UK
Posts: 52,446
Re: Spaceships and astronomy
I think it's something to do with whether the internal angles of triangles add up to 180 degrees. in a flat universe, they do.
Take a sheet of paper. Draw a triangle on it, using straight edges and stuff. The internal angles add up to 180 degrees.
Now wrap that paper around a large toilet roll. The paper seems curved, but the angles of the triangle drawn on it still add up to 180 degrees. It's flat.
Draw a triangle on the surface of a smooth sphere. The internal angles of that triangle will add up to more than 180 degrees. Not flat.
I think that's it.
I could be wrong. I'moften a figment of mu own imagination - never somebody else's...
Take a sheet of paper. Draw a triangle on it, using straight edges and stuff. The internal angles add up to 180 degrees.
Now wrap that paper around a large toilet roll. The paper seems curved, but the angles of the triangle drawn on it still add up to 180 degrees. It's flat.
Draw a triangle on the surface of a smooth sphere. The internal angles of that triangle will add up to more than 180 degrees. Not flat.
I think that's it.
I could be wrong. I'moften a figment of mu own imagination - never somebody else's...
Jun 16th 2019, 8:29 pm
#317
BE Forum Addict
Joined: Jun 2010
Posts: 2,847
Re: Spaceships and astronomy
Or more.
Jun 16th 2019, 9:47 pm
#318
`
Joined: Oct 2003
Posts: 38,613
Re: Spaceships and astronomy
Jun 17th 2019, 2:03 am
#319
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Joined: Feb 2013
Location: State College Pa.
Posts: 1,585
Re: Spaceships and astronomy
I once won an easter egg from a maths teacher with similar to this. It was a puzzle posed to the class about how the sum of a triangle could be more than 180° . I solved & answered this but said teacher was not pleased at all. I waited long for that flippin' egg and that wretched man thereafter made my life uncomfortable.
Jun 17th 2019, 2:13 am
#320
`
Joined: Oct 2003
Posts: 38,613
Re: Spaceships and astronomy
That reminds me of the story of the great mathematician (to be) CF Gauss, who, as a child, was told to add all the numbers from 1-100 up - the teacher expecting it to take all lesson. Gauss did it in a couple of minutes, got it right, and explained the method. He wasn't popular either....
All I know is that bluddy easter egg was not worth the misery that dreadful man put me through for a long time afterward. When it was finally sneeringly & begrudgingly given to me, I gave it away. Shame, as treats like that were very few and far between at home.
Jun 17th 2019, 2:25 pm
#321
I have a comma problem
Joined: Feb 2009
Location: Fox Lake, IL (from Carrickfergus NI)
Posts: 49,598
Re: Spaceships and astronomy
Incidentally, I recommend the numberphile videos and their associated families in physics, computing and other fields to anyone, they're a great watch.
Jun 17th 2019, 2:39 pm
#322
Thread Starter
Joined: Dec 2001
Location: Dixie, ex UK
Posts: 52,446
Jun 17th 2019, 2:45 pm
#323
I have a comma problem
Joined: Feb 2009
Location: Fox Lake, IL (from Carrickfergus NI)
Posts: 49,598
Re: Spaceships and astronomy
Lots of great astronomy content on their associated channel Deep Sky Videos, too.
Jun 17th 2019, 10:40 pm
#324
Yo
Joined: Nov 2012
Location: UK
Posts: 24,474
Re: Spaceships and astronomy
I was going to sketch this, but the best explanation I've found that I can point you at is Laurence Krauss' book
https://www.amazon.com/Universe-Noth.../dp/1451624468
https://www.amazon.com/Universe-Noth.../dp/1451624468
Mar 25th 2020, 12:45 am
#325
Forum Regular
Joined: Jul 2018
Location: California
Posts: 254
Re: Spaceships and astronomy
https://time.com/5802128/alexei-leon...wsletter-brief
"They eventually reached solid ground — however, after emerging from the craft they realized, cruelly, they were in a thick forest surrounded by wolves and bears, in a snowstorm."
I doubt if they would've been too unhappy!
"They eventually reached solid ground — however, after emerging from the craft they realized, cruelly, they were in a thick forest surrounded by wolves and bears, in a snowstorm."
I doubt if they would've been too unhappy!
Mar 25th 2020, 12:52 am
#326
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Joined: Feb 2013
Location: State College Pa.
Posts: 1,585
Re: Spaceships and astronomy
https://time.com/5802128/alexei-leon...wsletter-brief
"They eventually reached solid ground — however, after emerging from the craft they realized, cruelly, they were in a thick forest surrounded by wolves and bears, in a snowstorm."
"They eventually reached solid ground — however, after emerging from the craft they realized, cruelly, they were in a thick forest surrounded by wolves and bears, in a snowstorm."
Last edited by steveq; Mar 25th 2020 at 12:52 am. Reason: Spelling !
May 27th 2020, 8:26 pm
#329
Turning into a PA gal!
Joined: Feb 2013
Location: State College PA, finally!
Posts: 3,563
Re: Spaceships and astronomy
They will try again on Saturday 30 May at 15:22 local time.
