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View Full Version : Does the premise, "Its turtles all the way down," have a leg to stand on?



potoole
2012-Jun-16, 07:03 PM
I read, somewhere, that a woman suggested that the universe rests on the back of a huge turtle. When asked what was under the turtle, she said, "Another turtle." When asked what did that second turtle stand on, she replied, "After that its turtles all the way down".

Now, I'm just wondering if that postulation has a leg to stand on, or any grounds to support it. :D

Patrick

Stug III
2012-Jun-16, 07:16 PM
I wouldn't like to stick my neck out but I think it is a varient of the Shell Game.

potoole
2012-Jun-16, 07:19 PM
I wouldn't like to stick my neck out but I think it is a varient of the Shell Game.

Heh, heh, heh. :)

PO'T

Stug III
2012-Jun-16, 08:00 PM
Thank you, thank you, I'll be here all week. Try the guilinggao.

DonM435
2012-Jun-16, 08:46 PM
Is 0.999999... equal to 1? We had a few bits of discu8ssion on that topic.

Stug III
2012-Jun-16, 08:48 PM
0.9999999 equal to 1? No, they're turtally different . . .

Strange
2012-Jun-16, 08:50 PM
Is 0.999999... equal to 1? We had a few bits of discu8ssion on that topic.

Is discu8ssion equal to discussion? I don't think we have discussed that.

potoole
2012-Jun-16, 08:54 PM
Is 0.999999... equal to 1? We had a few bits of discu8ssion on that topic.

Not exactly, but pretty close.

PO'T

Strange
2012-Jun-16, 09:03 PM
Is 0.999999... equal to 1? We had a few bits of discu8ssion on that topic.Not exactly, but pretty close.

PO'T

Is this just deja vu or an actual nightmare...

potoole
2012-Jun-16, 09:08 PM
Its deja vu all over, again.
Yogi Berra

Chuck
2012-Jun-16, 09:57 PM
If each turtle has half the mass of the one above it then the infinite stack of them has twice of mass of the top turtle.

Van Rijn
2012-Jun-16, 10:35 PM
Well, if the universe is infinite in scale, then there could be an infinite number of turtles. However, a large stack of turtles standing on each others' backs would eventually collapse from self-gravitation, so "turtles all the way down" can't work if the laws of physics remains the same.

schlaugh
2012-Jun-16, 10:59 PM
If each turtle has half the mass of the one above it then the infinite stack of them has twice of mass of the top turtle.

Does this imply a Planck turtle?

Luckmeister
2012-Jun-16, 11:19 PM
I read, somewhere, that a woman suggested that the universe rests on the back of a huge turtle.

It's the Earth (or world) that is commonly said (http://en.wikipedia.org/wiki/Turtles_all_the_way_down) to be supported by one or more turtles, not the universe.

But which is more believable? Through observation, we cannot see a turtle holding up the Earth but since we can't see the edge of the universe.....:think:

potoole
2012-Jun-16, 11:34 PM
To all the replies above - Oh!

PO'T

Trebuchet
2012-Jun-16, 11:58 PM
Now, I'm just wondering if that postulation has a leg to stand on, or any grounds to support it. :D


Four legs! Per turtle, of course.

I think, however, that there are four elephants interposed between the earth and the first turtle. That's sixteen more legs.

darkhunter
2012-Jun-17, 03:44 AM
Great A'Tuin (Chelys galactica) swims through space. He (or she) doesn't have to stand on anything. ;)

Nicolas
2012-Jun-17, 09:13 AM
If each turtle has half the mass of the one above it then the infinite stack of them has twice of mass of the top turtle.

Finally someone agrees with me that 1.999...(infinite nines) equals 2.

Nicolas
2012-Jun-17, 09:18 AM
The topic starter got us on the wrong track by making us believe the theory claimed it was no sea turtle but a land turtle supporting the earth (or Universe). I believe he did that on tortoise.

jokergirl
2012-Jun-17, 11:24 AM
In that case, the tortoise has no legs to stand on. On the other hand, it does not need to stand on another turtle, swimming in primordial soup as it were.

chrlzs
2012-Jun-17, 12:08 PM
17097
Six visible, twelve by inference.
..Do I win a prize? :p

BTW, I first read this in Broca's Brain by Carl Sagan (p.293), but note the first sentence - 'apocryphal'? I quoth from my copy..

Some ancient Asian cosmological views are close to the idea of an infinite regression of causes, as exemplified in the following apocryphal story: A Western traveler encountering an Oriental philosopher asks him to describe the nature of the world:
It is a great ball resting on the flat back of the world turtle.
Ah yes, but what does the world turtle stand on?
On the back of a still larger turtle.
Yes, but what does he stand on?
A very perceptive question. But its no use, mister; its
turtles all the way down.
...

Jens
2012-Jun-17, 12:31 PM
I read, somewhere, that a woman suggested that the universe rests on the back of a huge turtle. When asked what was under the turtle, she said, "Another turtle." When asked what did that second turtle stand on, she replied, "After that its turtles all the way down".

Now, I'm just wondering if that postulation has a leg to stand on, or any grounds to support it. :D


I don't know if you really wanted a serious answer to this. But it just so happened that I asked a particle physicist about it. I said, is it possible that quarks are really composites of other particles and those in turn are composites of other particles, going on forever? Basically, his answer was, physicists don't really worry much about that. It might be right, and might be wrong, but we have no way of measuring it so it's not something we worry about.

"It's something that philosophers think about." He, he.

potoole
2012-Jun-17, 10:40 PM
I don't know if you really wanted a serious answer to this. But it just so happened that I asked a particle physicist about it. I said, is it possible that quarks are really composites of other particles and those in turn are composites of other particles, going on forever? Basically, his answer was, physicists don't really worry much about that. It might be right, and might be wrong, but we have no way of measuring it so it's not something we worry about.

"It's something that philosophers think about." He, he.

The scientists keep confusing us with facts.
Are they gonna stop at quarks? :think:

Chuck
2012-Jun-17, 10:56 PM
If each turtle is half the height of the turtle above it then the whole infinite stack will be twice the height of the top turtle. Since there will still be no bottom turtle, the stack doesn't need anything to stand on.

John Mendenhall
2012-Jun-18, 01:23 AM
If each turtle is half the height of the turtle above it then the whole infinite stack will be twice the height of the top turtle. Since there will still be no bottom turtle, the stack doesn't need anything to stand on.

Yes, but then you get into the question of the Planck limit again. When the limit is reached, will the whole stack go kerPlanck?

Nicolas
2012-Jun-18, 07:10 AM
So apparently the bottom turtle is standing on a planck. Mystery solved.

Tobin Dax
2012-Jun-19, 01:41 AM
17097
You might have just turned cosmology on it's head. Obviously, from that picture, it's turtles all the way up!

DonM435
2012-Jun-19, 12:42 PM
According to Jonathan Swift, it's actually fleas all the way down.



But there must be a dog in there somewhere!

Hornblower
2012-Jun-19, 01:17 PM
I remember a chapter in a book by Isaac Asimov, if I am not mistaken, in which one ancient society envisioned the Earth as a flat platform supported by four columns. Each column rested on the back of an elephant, and the four elephants stood on the back of a great turtle that was swimming in a vast ocean. Of course there was no observational evidence for or against whatever was supposed to be below the ground, so this model was based on faith rather than on science.

These people started having philosophical difficulty when it occurred to someone to ask what supported the water in that ocean. They knew very well that water naturally settled to low places on the ground. It was here that the head-scratcher concept of infinity was rearing its ugly head. The author portrayed the Greek thinkers as getting around this conundrum in part by envisioning a spherical Earth which naturally settles to its own center. That did not eliminate infinity, but rather displaced it from direct contact with the Earth.

DonM435
2012-Jun-19, 02:39 PM
Turtles were a good choice due to their design. Or rather, their evolution. I'd guess as they can be greatly enlarged without losing functionality. I'd think that a really big turtle could support a tall column of smaller turtles, up to some point, of course.

It wouldn't work for most bugs, including fleas, as their little legs, howevermany, couldn't take the stress without alteration. No, if you want to stack some critters, turtles would be a good choice.

Swift
2012-Jun-19, 04:41 PM
First, assume a spherical turtle....

NEOWatcher
2012-Jun-19, 07:52 PM
You might have just turned cosmology on it's head. Obviously, from that picture, it's turtles all the way up!
No; the picture is just upside down. They are bench pressing the earth.

BigDon
2012-Jun-23, 12:42 AM
Finally someone agrees with me that 1.999...(infinite nines) equals 2.

Except it doesn't...this is math we're talking about. Not some sloppy best guess and feelings will do discipline, like medicine or engineering...

Tobin Dax
2012-Jun-23, 04:01 AM
Except it doesn't...this is math we're talking about. Not some sloppy best guess and feelings will do discipline, like medicine or engineering...

The word "infinite" is the key, Don. They are equal. There are a few older threads around on the topic (of 0.999... equaling 1), but I can't find them at the moment.

Nicolas
2012-Jun-23, 08:03 AM
Except it doesn't...this is math we're talking about. Not some sloppy best guess and feelings will do discipline, like medicine or engineering...

Somehow I want to expand on what Tobin Dax said in an attempt to keep this sidetrack short. :)

In sloppy disciplines such as rocket engineering or brain surgery, we could agree that 1.9999 equals 2.
In an exact discipline like math, we can never say that 1.9999 equals 2.
However, in the exact discipline math, there is a definition of infinity that states that 1.999... (mathematically infinite nines) equals 2 by definition of infinity.

Now there is a beatiful old thread to argue this point further (please don't :D); the above is just the definitions as they are.

Noclevername
2012-Jun-23, 04:25 PM
Since the Flat Earth hypothesis is largely disproven, it would have to be turtles all the way in, with the turtles at the Earth's core shrinking to infinitesimal size.

Solfe
2012-Jun-24, 02:08 AM
Anyone here read Yertle the Turtle? The turtles get upset if you stack them too high.

StratMaster
2012-Jun-24, 06:37 AM
Finally someone agrees with me that 1.999...(infinite nines) equals 2.

I agree with you, even if I think the example seems more relevant to the equality of of 1.111...(base two) and 10 (base two).

Nicolas
2012-Jun-24, 09:52 AM
Given that it are 4 elephants on the back of a turtle supporting the earth, I'd suggest we use base 4 in this case.

Noclevername
2012-Jun-26, 09:24 PM
Maybe it's one turtle with infinitely long legs.

Swift
2012-Jun-26, 09:47 PM
Maybe dark matter is made of turtles?

Noclevername
2012-Jun-28, 02:59 PM
Maybe dark matter is made of turtles?

So A'Tuin is swimming in an aether of quantum pico-turtle foam?

Swift
2012-Jun-28, 06:07 PM
We had some quantum pico-turtle foam in the terrarium before I cleaned it out.