Comments on: epi – pi

By: Gerson W. Barbosa

Gerson W. Barbosa — Wed, 06 Oct 2010 20:00:03 +0000

I’ve come up with a slightly more weird expression:

(sqrt(2)*(pi^17-4*e^pi*(e^pi-pi)))/4 = 99999999.979

I guess this would have worked in the XKCD comic as well

By: Julie

Julie — Tue, 13 Jul 2010 17:07:05 +0000

“Hey, no one’s mentioned the alt-text in that XKCD comic yet:

“Also, I hear the 4th root of (9^2 + 19^2/22) is pi.”

Someone with Mathematica try that out.”

Why the hell would you need mathematica to do that? Put it in a calculator or use Google calculator.

By: Bas Joosten

Bas Joosten — Wed, 04 Nov 2009 12:47:56 +0000

In reply to Adam:
“Also, I hear the 4th root of (9^2 + 19^2/22) is pi.”
I have no mathematica, but I can do high precision calculations. Found out it is approximately pi up to the 9th digit. Aproximately equal is still unequal, of course.

By: ElBosso

ElBosso — Mon, 12 Oct 2009 18:43:16 +0000

1111,1111^2 = 1234567,87654 |*7,2
= 8888888,71109 |sqrt (4 times)
= 2,718335 -> nearly e^1 !
cool, isn´t it?
found out by myself!

By: Eikinkloster

Eikinkloster — Tue, 25 Aug 2009 17:46:53 +0000

For those who are pissed because they don’t get the whole fuss:

1) Click on the image. It will take you to the actual comic. The image is only the first of three frames.
2) The joke in a nutshell: e^pi – pi = 19.999099979, which is very very close to 20. So close that if you don’t know better, you’ll feel tempted to believe you’ve introduced some rounding error on the calculation. The math guy exploits this to drive the computer guys from ACM nuts trying to find where they were making the mistake.

By: adam

adam — Fri, 24 Jul 2009 16:56:43 +0000

Hey, no one’s mentioned the alt-text in that XKCD comic yet:

“Also, I hear the 4th root of (9^2 + 19^2/22) is pi.”

Someone with Mathematica try that out.

By: Steven

Steven — Tue, 03 Mar 2009 08:07:09 +0000

http://mathworld.wolfram.com/AlmostInteger.html

By: Action Lyrics

Action Lyrics — Wed, 18 Feb 2009 05:43:36 +0000

I agree with you, I think it’s just a coincidence.

There are plenty of them if u look for them.

Eg sqrt(10) approx = 22/7 approx = pi.

Even though none of those are integers.

By: Patrick

Patrick — Fri, 24 Oct 2008 18:31:50 +0000

The most explicit definition of e is e = 1 + 1/1! + 1/2! + 1/3! + …

This is a rapidly converging sum (remember n! = n times (n-1) times … times 1).

By: Sephiroth

Sephiroth — Mon, 17 Dec 2007 16:03:25 +0000

e=the tangent line of f(x)=e^x where x=0

By: Some other guy

Some other guy — Wed, 12 Sep 2007 03:24:34 +0000

Does anyone know the official definition of “e”?

I know one fact, that if you tetrate (see http://en.wikipedia.org/wiki/Tetration) e-rt(e) (The base-e root of e) to infinity, the result is e, but if you tetrate anything higher than that to infinity, be it just 10^-1000000000 higher, it goes to infinity. (Well, I actually found this out from experimentation.)

By: Brian

Brian — Tue, 13 Feb 2007 22:09:53 +0000

e[sup]pi>pi[sup]e

By: Brian

Brian — Sun, 11 Feb 2007 20:22:09 +0000

Thanx all for some very interesting posts. In response to Samuel’s hint of a deeper reason that e^pi > pi^e, let f(x) = ln(x)/x. Then f’(x)=(1-ln(x))/(x^2).
f’(x)=0 if and only if x=e, which yields a maximum at x=e for all positive values of x. So if A>0 and A not equal to e, f(e)>f(A)
ln(e)/e>ln(A)/A
Aln(e)>eln(A)
ln(e^A)>ln(A^e)
e^A>A^e
e^pi>pi^e is a special case.

By: Steve

Steve — Fri, 02 Feb 2007 10:51:57 +0000

Phill you B*$*Â£”% Hadn’t been aware of that webcomic before, thanks for giving me another way to waste time at work (as if i didn’t have enough already)

By: Patrick

Patrick — Thu, 01 Feb 2007 21:39:23 +0000

Phil is commenting on the fact that the result is near 20, but that’s not the end of joke. Read the rest of the comic!

By: Bill Nettles

Bill Nettles — Thu, 01 Feb 2007 20:35:49 +0000

Correction:
In Si units, the acceleration of gravity near the surface of the earth is very close to pi^2. Hmmmm. [I SQRT'd the wrong thing...that can be dangerous]

By: Bill Nettles

Bill Nettles — Thu, 01 Feb 2007 20:33:19 +0000

Physics has interesting numerical coincidences which suggest that our standard measurements need tweaking:

The number of seconds in a tropical year is about 3.1557 x 10^7 seconds, remarkably close to pi x 10^7. If the second was just a little “longer”, then they would match, as long as the earth doesn’t slow down.

In SI units, the acceleration of gravity near the surface of the earth is very close to the SQRT(pi). Hmmmm…

Finally, we know where Ol’ McDonalds Farm is: on the Argand Plain [sic] about 0.6517 units from the origin (wherever THAT is), 38.22 degress east of south. Check out e^(i^(e^(i^0))). Oh, and the imaginary component of the farm has a magnitude close to (slightly larger than) the mass-energy of the electron in MeV. Ooooo…

By: Quiet_Desperation

Quiet_Desperation — Thu, 01 Feb 2007 19:47:04 +0000

I used to like math humor until my uncle was killed in a tragic long division accident.

By: Rob

Rob — Thu, 01 Feb 2007 19:42:21 +0000

Sweet Lord Christ, could someone please explain what the $%*k this means to those of us who don’t get it?

Maybe we should just accept that we’re out of our league and leave you Matharians to enjoy yourselves, but I feel I’m smart enough to play with you guys if you’ll help me understand.

Thanks
Rob

By: Todd

Todd — Thu, 01 Feb 2007 19:13:47 +0000

It’s a coincidence.

Kind of like the coincidence that

10! (=10*9*8*…*3*2*1) is exactly equal to the number of seconds in 6 weeks.

Given that there are an infinite number of numbers, coincidences can always be found.

By: APP

APP — Thu, 01 Feb 2007 18:12:54 +0000

Pi itself is much more interesting in the first 10 digits you get all 10 digits. Of course this is in the base 10 number system which only appeals to us because we have 10 fingers.

Huh?

3.141592653…

Two 1′s, two 3′s, two 5′s, no 0′s, 7′s, or 8′s.

By: DennyMo

DennyMo — Thu, 01 Feb 2007 14:26:59 +0000

I was gonna make some pithy comment about those stupid emails that have you go through some silly math gymnastics and arrive at some result that sounds impressive or surprising. But then you all start throwing around imaginary numbers, natural logarithms, etc., makes my comment seem kinda sophomoric, so I’m gonna just keep my mouth shut…

By: AntiQuest

AntiQuest — Thu, 01 Feb 2007 14:25:46 +0000

I (physics student) caught out a few of the Comp Sci majors with this today. Not really significant but funny to see them struggle with thier program.

Oh and TomPaine, check out Tom Lehrer before you say mathematicians aren’t funny. Especially “That’s mathematics” (and “Werner von Braun” for the Phil’s interest…).

By: Kullat Nunu

Kullat Nunu — Thu, 01 Feb 2007 10:13:15 +0000

My favorite is

e^(i * pi) + 1 = 0

Three basic arithmetic functions (+, *, ^), five fundamental constants (0, 1, pi, e, i [= imaginary unit, i^2 = -1]), one equation.

And it is not a coincidence.

Ah, Dr. Goulu already mentioned it.

By: Lab Lemming

Lab Lemming — Thu, 01 Feb 2007 08:55:00 +0000

Some numerical coincidences are useful!

When I took geophysics, we would cancel out the pi that results from the earth’s orbit in various geophysical calculations by approximating a year as pi x 10^7 seconds. Obviously you don’t want the guys who do spacecraft trajectories using this trick, but it’s close enough for the order-of-magnitude type calculations that we did in undergrad planetary.