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Does Pi terminate or never?

Complexity said:
Actually, it would be very easy for you to describe if you actually had an answer.

Since the knowledge that you are claiming contradicts what is provable, full of beans you are.
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I think you're confusing ynot with yrreg.
 
Andrew Wiggin said:
Even with things like calculating the diameter of the observable universe, Pi reaches the limit of meaningful precision rather quickly. I don't have the figures at hand, but I remember Asimov calculating it in one of his essay series. Diameter of the observable universe calculated to less than the radius of a proton, or some such.

A
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Wikipedia says 39 decimal places are enough for the scenario you describe; quite a small number considering that the current record is in the low trillions of decimal places.
 
Mea culpa

ynot said:
Would it help for you to realise I'm merely joshin if I used alot of >>> :D:D:D:):):):cool::cool::eek::boggled::eye-poppi:jaw-dropp:blush::rolleyes::(:o:D:p
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Oops! I think I did confuse Ynot with Yrreg. Two years is a long time to be away...

My apologies. I'm glad that dueling is no longer in fashion, for I would surely die at dawn.

Yrreg would have held the position you adopted for our entertainment until the bloody end, believing it just to be contrary.

I'm wondering which other gaffs I'll make. Might as well get a bunch of them out of the way as quickly as possible. :o
 
Engineering may only have use for a paltry handful of Pi's decimal places, but there is more to life than engineering (important though it is).

Pi is transcendental and far beyond mere usefulness.
 
Andrew Wiggin said:
Even with things like calculating the diameter of the observable universe, Pi reaches the limit of meaningful precision rather quickly. I don't have the figures at hand, but I remember Asimov calculating it in one of his essay series. Diameter of the observable universe calculated to less than the radius of a proton, or some such.

A
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Now, I'm making this up as I go, but I think the situation's even worse than that.

Suppose we postulate a universe that has gravity and massive objects (for example, our universe). Now, that means space isn't flat and I think that means that the relationship between radius and circumference for a particular patch of space isn't exactly pi.

Of course, to the extent that you know the mass distribution, then you can compensate for the curvature of space (assuming that you're far, far better at math than I), but I suspect that the uncertainty principle keeps you from ever perfectly knowing the distribution of masses in a volume of space, so you're never perfectly know the curvature, so pi's utility may run out even sooner.

ETA: Or maybe it's a really small effect. I don't know.
 
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Thank you all, especially thanks for the April Fools hoax link to Snopes.

I can imagine there being a reporter getting hold of that "viral" story, second or more handed, then hearing the hoax had "come to an end", reporting that in a brief notation, and due to the wording, my acquaintance misreading that as an "end" of Pi.

Well, that is just a fantasy, but it might explain how he came to believe that...:D

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On a related note, how many ways are there to calculate the digits of Pi?

I know that NO measurement of a circle can possibly yield more than a handful of digits, and I was once told of a method (semi-graphical) using inscribed and circumscribed polygons or some such, but I think I have heard there are better algorithms.

Is it possible to get a listing w/references to the method?

Thanks to all,

Dave
 
dasmiller said:
Now, I'm making this up as I go, but I think the situation's even worse than that.

Suppose we postulate a universe that has gravity and massive objects (for example, our universe). Now, that means space isn't flat and I think that means that the relationship between radius and circumference for a particular patch of space isn't exactly pi.

Of course, to the extent that you know the mass distribution, then you can compensate for the curvature of space (assuming that you're far, far better at math than I), but I suspect that the uncertainty principle keeps you from ever perfectly knowing the distribution of masses in a volume of space, so you're never perfectly know the curvature, so pi's utility may run out even sooner.

ETA: Or maybe it's a really small effect. I don't know.
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Space isn't flat, but the rulers we use are imbedded in it so they flex and stretch along with it, so flat, newtonian space is a pretty good approximation. Pi would vary by space curvature assuming a rigid, non imbedded ruler so that would make it rather useless on a universal scale, but it also makes the eyes cross and the mind warp, so that's OK...

A
 
Complete non-mathematical amateur here but doesn't the relationship among "e", the square root of -1, and the value of the ratio of the circumference of a circle to its diameter mandate that it doesn't terminate?

Can you also curve the circle so that pi is an integer? What would that do to "e" and the square root of -1?
 
CaveDave said:
On a related note, how many ways are there to calculate the digits of Pi?

I know that NO measurement of a circle can possibly yield more than a handful of digits, and I was once told of a method (semi-graphical) using inscribed and circumscribed polygons or some such, but I think I have heard there are better algorithms.

Is it possible to get a listing w/references to the method?

Thanks to all,

Dave
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This Wiki page has a lovely collection of them. Some of these people must have had ... strange... minds... (I'm looking at you, Ramanujan)

I've been idly wondering - would physical reality be observably different in any way if pi was equal to 3, or any other rational number? I.e., is the irrational or transcendental character of pi in any way responsible for major characteristics of physical reality?
 
Pi is 3 for sufficiently large values of 3. There. Terminated.. ;-)
 
erlando said:
Pi is 3 for sufficiently large values of 3. There. Terminated.. ;-)
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Is that possible? Is there such a thing as 3-ish or pi-ish? I could easily be falling for some kind of inside math joke but you'd have to explain it...which would ruin its humour value but might be educational in some way.
 
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