# Happy Pi day

All of you have a happy international Pi day.

pi=3.13? may wanna check those calculations again =]

It's not pi day yet..

woohoo, pi day is finally here!! :uhh: :tongue: Can't wait til pi+0.01 day

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woohoo, pi day is finally here!! :uhh: :tongue: Can't wait til pi+0.01 day

Another hour and a half for me..

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Hmmmm, $\pi$

I'd rather remember today as Einstein's birth anniversary, and wait till April 31st for pi-day.

pi day again already? Just where has the year gone? I didn't even get my pi day shopping done.

Homework Helper
Are there e and i days, too? :tongue2:

Are there e and i days, too? :tongue2:
e-day: 27th January
i-day: e^(i*pi/2) = 27th Jan^(i*31st April/2) = :uhh:

Homework Helper
The only problem is, how to decide if it's celebrated at 3:14 am or 3:14 pm.

The only problem is, how to decide if it's celebrated at 3:14 am or 3:14 pm.

3.14 is taken care of by the date. So you celebrate it at 1:59:26(.5) in the morning (or in the afternoon if you don't use a 24-hour clock).

The only problem is, how to decide if it's celebrated at 3:14 am or 3:14 pm.
I don't see it as a problem. We can precisely define pi's birth in this scheme, minutes second and everything, can't we ?

I mean :
month day hour minute sec...
3 14 15 9 27

now, maybe I see your objection
why not :
month day hour minute sec...
3 1 1 9 2
or :
month day hour minute sec...
3 14 1 59 27
...

indeed, I assumed that one fills as much decimal places as possible at each step. Thus for instance I took 9 minutes, because 92 minutes exceeds 60=1h... This might be a little simplistic, or even unesthetical. But eh, why not celebrating on the first of march otherwise ?

A more esthetical solution, would be to write down everthing in a decimal basis.

3.14 is taken care of by the date. So you celebrate it at 1:59:26(.5) in the morning (or in the afternoon if you don't use a 24-hour clock).
I do use a 24-hour clock, but I would have thought we need to pick up 15:9:26

this is highly debatable...

Homework Helper
Now you see it indeed is a sophisticated issue, gentlemen.

Homework Helper
Oh yes, and there's another issue. In my country, we write the day first, and then the month, so we have no pi day! Which proves that the pi day is a those-who-write-the-month-first-o-centric product. Down with it! :tongue2:

Math Is Hard
Staff Emeritus
Gold Member
Pi day at last! Can't wait to get up to campus at lunch time. Usually the math department sells yummy pie slices for a buck.

Oh yes, and there's another issue. In my country, we write the day first, and then the month, so we have no pi day! Which proves that the pi day is a those-who-write-the-month-first-o-centric product. Down with it! :tongue2:
And that's why I said that I would rather wait will April 31st. This is strictly a US-centric Pi-day.

I know the first 120 digits of pi:

3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651

whew!

thats all I know off the top of my head.

thats all I know off the top of my head.
so, what is the accuracy with which you can calculate the circumference of the galaxy, supposing you know it's diameter with a precision equivalent to that of the size of the proton ?

Homework Helper
I know the first 120 digits of pi:

3.14159265358979323846264338327950288419716939937510582097494459230781640628620899862803482534211706798214808651

whew!

thats all I know off the top of my head.

Did you have a pi-digit-listing contest today? :tongue:

haha, our math building had free pie for all starting at 1:59 this afternoon.
and you can also buy pi day t-shirts for pi^2 dollars ($9.87) radou Homework Helper and you can also buy pi day t-shirts for pi^2 dollars ($9.87)

Did someone actually buy one of these? :rofl:

Wow, 120 digits eh?
I know:
3.141592653597932384626

22 digits...

so, what is the accuracy with which you can calculate the circumference of the galaxy, supposing you know it's diameter with a precision equivalent to that of the size of the proton ?

I don't really know the exact measurements of the galaxy, in fact nobody on Earth does. However, the galactic disk has been estimated to have a radius of 60,000 light years. Based on this figure, I would estimate the circumference to be around 360,000 light years. Or, if you want a more accurate figure (assuming pi = 3.14), it is somewhere between 376,800 - 378,000 light years.

Did you have a pi-digit-listing contest today? :tongue:

No, unfortunately. In fact, even the math geeks in my class were unenthusiastic about it (probably because of social pressure ). But, even if we did at my school, I would have still owned them. Most people don't remember past 3.14, and most of the so-called math-wiz's in my school know only about 20 digits or so.

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memorizing pi isn't math.

There is no more use to memorizing pi than to memorizing a random number. Although the story of the calculation of pi is very interesting.

If the math 'whiz's' spent their time memorizing pi, they wouldn't have time to become good at math.

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One of my high school math teachers said he used to memorize pi (while a math grad student at UIUC) to impress his friends (I think he said that he knew a few hundred digits). I never understood why anyone would bother memorizing pi, I can't even think of the last time I used pi.

My calculator knows pi to 10 digits, thats good enough for my uses. lol :)

I can sort of understand it, I mean, it is an important number.. But at the end of the day its probably better to memorize something that can be used. (other than to impress friends)

Definitely no more useful then memorizing any random number :P Its kind of odd that someone would think that a math student should know pi to more then 10 decimal places.

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My calculator knows pi to 10 digits, thats good enough for my uses. lol :)

I can sort of understand it, I mean, it is an important number.. But at the end of the day its probably better to memorize something that can be used. (other than to impress friends)

Definitely no more useful then memorizing any random number :P Its kind of odd that someone would think that a math student should know pi to more then 10 decimal places.
Well in principle you don't have to memorize it, afteral there is a formula that gives you the value of any particular digit of $\pi$.