## Search found 198 matches

- Tue Apr 19, 2011 3:15 pm UTC
- Forum: XKCD Meetups
- Topic: Melbourne meet-up?
- Replies:
**449** - Views:
**111865**

### Re: Melbourne meet-up?

I might make it.

- Sun Apr 17, 2011 10:52 am UTC
- Forum: XKCD Meetups
- Topic: Melbourne meet-up?
- Replies:
**449** - Views:
**111865**

### Re: Melbourne meet-up?

I was suggesting that fertilizer might make trousers reproduce.

- Sun Apr 17, 2011 5:20 am UTC
- Forum: XKCD Meetups
- Topic: Melbourne meet-up?
- Replies:
**449** - Views:
**111865**

### Re: Melbourne meet-up?

Have your trousers sprouted?

- Sat Apr 16, 2011 9:04 am UTC
- Forum: XKCD Meetups
- Topic: Melbourne meet-up?
- Replies:
**449** - Views:
**111865**

### Re: Melbourne meet-up?

Yeah, that game is looking at bit like EVE Online: I want to hear about or watch really good players, but I'm not sure I'd want to play it myself...

That photo really makes it look like my head is 4 times bigger than Jess'.

That photo really makes it look like my head is 4 times bigger than Jess'.

- Sat Apr 16, 2011 7:45 am UTC
- Forum: XKCD Meetups
- Topic: Melbourne meet-up?
- Replies:
**449** - Views:
**111865**

### Re: Melbourne meet-up?

http://www.segerman.org/random/xkcd_meetup_16_4_2011.jpg End of the day myspace photo! ToeOfDoom, Gelsamel, dragon, theduffman dinosplosion, fantasyprone, __jess, HenryS (I didn't remember everyone's name, someone tell me how to fill in the blanks.) (Edit: Thanks!)

- Fri Apr 08, 2011 1:06 pm UTC
- Forum: XKCD Meetups
- Topic: Melbourne meet-up?
- Replies:
**449** - Views:
**111865**

### Re: Melbourne meet-up?

Randomly checked the meetup forum for the first time ever, and there's one happening a block away from me next week. Bizarre.

Carlton gardens is pretty big. Which bit?

Carlton gardens is pretty big. Which bit?

- Wed Sep 22, 2010 2:30 pm UTC
- Forum: Mathematics
- Topic: Which is it? (straight line or circle through a portal?)
- Replies:
**33** - Views:
**4991**

### Re: Which is it? (straight line or circle through a portal?)

I happen to know someone who works at Valve, and pointed out that Portal is really about applying a physics engine to Euclidean orbifolds. I think there is a trend towards more complicated and interesting topology and geometry in computer games (Portal, Fez, and upcoming Miegakure to list a few exam...

- Thu May 06, 2010 2:18 pm UTC
- Forum: Mathematics
- Topic: Fitting circles into a circle
- Replies:
**6** - Views:
**1784**

### Re: Fitting circles into a circle

The first example to think about is two circles of half radius of the original. Their total area is exactly half of the original circle, and they only just fit, so 50% is an upper bound on what could be possible.

- Wed May 05, 2010 8:51 pm UTC
- Forum: Mathematics
- Topic: Fitting circles into a circle
- Replies:
**6** - Views:
**1784**

### Fitting circles into a circle

I don't think this has been asked before... Suppose you have an open circular disk D in the Euclidean plane. Suppose I give you a finite collection \{D_1, D_2, \ldots, D_n\} of open circular disks whose total area is at most half the area of D . Can you always arrange these disks to fit inside of D ...

- Thu Nov 05, 2009 5:18 pm UTC
- Forum: Mathematics
- Topic: Can anyone maximize this expression?
- Replies:
**11** - Views:
**1581**

### Re: Can anyone maximize this expression?

Write some code and generate some data?

Presumably you can get numerical answers up to the biggest size of any real life game very easily.

Presumably you can get numerical answers up to the biggest size of any real life game very easily.

- Sat Oct 17, 2009 5:04 am UTC
- Forum: Mathematics
- Topic: Definition of dy and dx?
- Replies:
**16** - Views:
**1893**

### Re: Definition of dy and dx?

In the context of a calculus class I think differentials are a terrible idea. Everything you can do with them you can do with linear approximation, and much less confusingly. In the class I'm teaching right now, we did exactly that.

- Mon Oct 12, 2009 3:13 am UTC
- Forum: Mathematics
- Topic: Becoming a Mathematician?
- Replies:
**17** - Views:
**4676**

### Re: Becoming a Mathematician?

Be aware that grad school is a pyramid scheme. 1 tenured professor teaches 10+ PhD students in their career, and after they retire maybe gets replaced by a single professor (or not). It isn't quite as bad as this, there are lots of undergraduate institutions without graduate programs that need prof...

- Mon Oct 05, 2009 8:43 pm UTC
- Forum: Mathematics
- Topic: Inverse functions and derivatives
- Replies:
**3** - Views:
**2083**

### Re: Inverse functions and derivatives

I think you're supposed to use the result that (f -1 )'(x) = (f'(x)) -1 . (The inverse function graph is a reflection of the original function graph along the line y=x, so you can tell what happens to the reflected tangent line as well: the slope of the new tangent is the inverse of the slope of the...

- Sun Sep 06, 2009 9:12 pm UTC
- Forum: Mathematics
- Topic: Why Do Mathematicians Play Go?
- Replies:
**23** - Views:
**2459**

### Re: Why Do Mathematicians Play Go?

According to the Wikipedia link, Many Faces of Go is the best computer program, and according to the M.F. Go website , at its strongest level it's 2 Kyu on a 19x19 board, or 3 Dan on a 9x9 board. That means on a 19x19 board it's equivalent to a top-tier amateur player, and on a 9x9 it's as good as ...

- Mon Jul 20, 2009 3:23 am UTC
- Forum: Mathematics
- Topic: What should I put on my "Calc Clock"?
- Replies:
**12** - Views:
**2067**

### Re: What should I put on my "Calc Clock"?

I think it would be good to have some number (not necessarily 12) of important constants arranged around the circle at the correct positions mod 12. So pi would appear a little below the right hand middle point of the circle, and 163 would appear in the 7 o clock position.

- Thu Jul 02, 2009 4:58 am UTC
- Forum: Mathematics
- Topic: chaos grapher
- Replies:
**9** - Views:
**1775**

### Re: chaos grapher

Python Imaging Library might be useful for producing pictures.

- Sat Apr 11, 2009 6:08 am UTC
- Forum: News & Articles
- Topic: Students Fear Math
- Replies:
**42** - Views:
**4818**

### Re: Students Fear Math

I've read in a few places opinions from mathematicians along the lines of the big problem with math(s) education being the focus on calculus as the core goal of the high school curriculum. This is a problem because calculus really isn't that useful for most people, unless they go on to study the sci...

- Mon Apr 06, 2009 6:55 am UTC
- Forum: Mathematics
- Topic: Spheres and cubes in high dimensions
- Replies:
**7** - Views:
**1048**

### Re: Spheres and cubes in high dimensions

According to http://en.wikipedia.org/wiki/N-sphere , if V_n is the volume of an n -ball of radius R then \frac{V_n}{R^n} \rightarrow 0 as n\rightarrow \infty . The largest that any ball that fits inside a cube of side length 2 can be is the ball of radius 1, and so its volume goes to 0, whereas the...

- Sat Apr 04, 2009 9:53 pm UTC
- Forum: Logic Puzzles
- Topic: The Devil's Quarter Game
- Replies:
**87** - Views:
**40012**

### Re: The Devil's Quarter Game

Ok then, again with quarters of radius 1: Devil plays first at (-n,0) (n is some big number) Player plays at (0.5,0) (which is not mirror-able and blocks the center position so:) Devil plays at (n,0) Player plays at (-1.5,0) (not mirror-able, cent...

- Sat Apr 04, 2009 5:45 pm UTC
- Forum: Logic Puzzles
- Topic: The Devil's Quarter Game
- Replies:
**87** - Views:
**40012**

### Re: The Devil's Quarter Game

Right, that's exactly the problem with the example I gave: since the quarters are radius 1, there is no room to put one in the center. If the game is played "on a grid", by which I assume you mean that there are a finite number of non-overlapping spots on which a quarter can be played...

- Sat Apr 04, 2009 3:48 pm UTC
- Forum: Logic Puzzles
- Topic: The Devil's Quarter Game
- Replies:
**87** - Views:
**40012**

### Re: The Devil's Quarter Game

What happens if the following are the first two moves (played with circles of radius 1):

**Spoiler:**

- Sun Mar 22, 2009 8:32 pm UTC
- Forum: Logic Puzzles
- Topic: Image cypher
- Replies:
**11** - Views:
**2524**

### Re: Image cypher

Here's an entirely different image cypher (I was playing this kind of game on a different forum some time ago).

- Sun Mar 22, 2009 8:30 pm UTC
- Forum: Logic Puzzles
- Topic: Image cypher
- Replies:
**11** - Views:
**2524**

### Re: Image cypher

Actaeus wrote:HenryS:Spoiler:

**Spoiler:**

- Sun Mar 22, 2009 6:25 pm UTC
- Forum: Logic Puzzles
- Topic: Image cypher
- Replies:
**11** - Views:
**2524**

### Re: Image cypher

**Spoiler:**

- Sun Mar 15, 2009 6:34 am UTC
- Forum: Mathematics
- Topic: Fair multiple choice test
- Replies:
**11** - Views:
**1892**

### Re: Fair multiple choice test

I taught multivariable calculus last semester using an online multiple choice system for homework. It did have some advantages over open response (and of course the disadvantages people have already mentioned). For one, students get immediate feedback on if their answer is correct, and have the oppo...

- Tue Mar 03, 2009 5:06 pm UTC
- Forum: Mathematics
- Topic: Math and instant messaging
- Replies:
**2** - Views:
**1139**

### Re: Math and instant messaging

There is also the facebook latex app: http://apps.facebook.com/mathematics/, although that works in messages and wall posts rather than IM.

- Mon Feb 23, 2009 4:23 pm UTC
- Forum: Individual XKCD Comic Threads
- Topic: 0547: "Simple"
- Replies:
**121** - Views:
**23471**

### Re: "Simple" Discussion

Re: math professors explaining things in simple English: There certainly is a tension between making a proof or explanation short versus making it more understandable, but it isn't as simple as gaining one loses the other. Precision of language is very important in mathematics, it isn't good enough ...

- Fri Feb 13, 2009 4:18 pm UTC
- Forum: Mathematics
- Topic: best excuse for being fat!
- Replies:
**17** - Views:
**2744**

### Re: best excuse for being fat!

You mean surface area to volume ratio. And the insulation probably doesn't hurt either

- Tue Feb 10, 2009 5:23 am UTC
- Forum: Mathematics
- Topic: What is the smallest positive integer with no google hits?
- Replies:
**34** - Views:
**4864**

### Re: What is the smallest positive integer with no google hits?

Right, if we are going to allow non standard representations to count, then we should just go all out and note that "the smallest positive integer with no google hits" currently returns 2 hits, and therefore does not exist...

- Mon Feb 09, 2009 7:26 am UTC
- Forum: Mathematics
- Topic: What is the smallest positive integer with no google hits?
- Replies:
**34** - Views:
**4864**

### Re: What is the smallest positive integer with no google hits?

I know neither the answer nor an efficient way to find it. Someone just asked me what I would guess (my initial guess was something around 100000, way too low). I suspect it might be relatively quick for someone internal to Google to find out.

- Sat Feb 07, 2009 10:53 pm UTC
- Forum: Mathematics
- Topic: What is the smallest positive integer with no google hits?
- Replies:
**34** - Views:
**4864**

### Re: What is the smallest positive integer with no google hits?

I wasn't sure about the forum placement, but then I read somewhere else about someone estimating the answer using a smattering of probability theory. http://godplaysdice.blogspot.com/2008/09/first-number-not-in-google.html thinks that the answer has to be in the high eight digits.

- Sat Feb 07, 2009 8:44 pm UTC
- Forum: Mathematics
- Topic: What is the smallest positive integer with no google hits?
- Replies:
**34** - Views:
**4864**

### What is the smallest positive integer with no google hits?

So, what would you guess is the smallest positive integer with no google hits?

- Fri Feb 06, 2009 10:13 pm UTC
- Forum: Mathematics
- Topic: Line Integral of a Space-Filling Curve
- Replies:
**6** - Views:
**965**

### Re: Line Integral of a Space-Filling Curve

Although, if the function is holomorphic, then the integral is 0 no matter the sequence of approximations.

- Fri Feb 06, 2009 9:10 pm UTC
- Forum: Mathematics
- Topic: Line Integral of a Space-Filling Curve
- Replies:
**6** - Views:
**965**

### Re: Line Integral of a Space-Filling Curve

Well, I was thinking along the lines of contour integrals of holomorphic or meromorphic functions, when you should get a sensible answer of integrating around the Koch snowflake, as long as there aren't any poles too near the curve. I see what you mean though: even in this case the limit only exists...

- Fri Feb 06, 2009 7:29 pm UTC
- Forum: Mathematics
- Topic: Line Integral of a Space-Filling Curve
- Replies:
**6** - Views:
**965**

### Re: Line Integral of a Space-Filling Curve

You could try evaluating the integral along the curves approaching the space filling curve, for many of the constructions the curve is piecewise, so these will be possible to integrate. Then see if the limit exists. I would imagine that you'd get something sensible for integrating around the Koch cu...

- Mon Jan 12, 2009 12:41 am UTC
- Forum: Mathematics
- Topic: Where to publish
- Replies:
**10** - Views:
**1461**

### Re: Where to publish

It is on arXiv?

- Thu Nov 27, 2008 8:11 pm UTC
- Forum: Logic Puzzles
- Topic: Portal Paradox
- Replies:
**137** - Views:
**33989**

### Re: Portal Paradox

Basically, if I can send information from one end of the barn to the other quickly enough (ie faster than light), then there are two distinct versions of reality, one in which the barn can be closed, trapping the pole and its bearer inside (the version from the barn person (...master?)), and the ot...

- Tue Nov 18, 2008 5:05 am UTC
- Forum: Mathematics
- Topic: Trouble using Beamer
- Replies:
**3** - Views:
**1629**

### Re: Trouble using Beamer

I've used pdf figures and pdflatex to compile beamer code, has worked well.

- Mon Nov 17, 2008 7:11 am UTC
- Forum: Individual XKCD Comic Threads
- Topic: 0505: "A Bunch of Rocks"
- Replies:
**406** - Views:
**117406**

### Re: "A Bunch of Rocks" Discussion

The Swiss patent office reference implies that desert guy is Einstein.

- Sat Nov 15, 2008 9:20 am UTC
- Forum: Logic Puzzles
- Topic: Portal Paradox
- Replies:
**137** - Views:
**33989**

### Re: Portal Paradox

Portals do violate one concept in relativity automatically-information can't be transferred faster than c. I don't think there's a problem here, you get the same effect with wormholes, which afaik are possible in relativity. All you have there is the wrong concept of distance. Space-time with a por...