If an extra dimension exists, it must have a size of less than 44 microns.

http://www.npl.washington.edu/eotwash/p ... 021101.pdf

## Search found 548 matches

- Sat Jun 05, 2010 8:30 pm UTC
- Forum: Science
- Topic: Evidence for Extra Dimensions?
- Replies:
**31** - Views:
**4319**

- Fri Jun 04, 2010 1:14 pm UTC
- Forum: Science
- Topic: Find the paper with the coolest title.
- Replies:
**11** - Views:
**2578**

- Thu Apr 29, 2010 10:18 pm UTC
- Forum: Science
- Topic: People who just don't get it
- Replies:
**23** - Views:
**2825**

### Re: People who just don't get it

And I wonder if spelling errors count as mistakes.

- Thu Apr 29, 2010 10:17 pm UTC
- Forum: Science
- Topic: What determines the lifespan of an organism?
- Replies:
**32** - Views:
**3191**

### Re: What determines the lifespan of an organism?

By scaling arguments, all organisms have about the same number of total heartbeats. Larger animals have slower heart beats, so they live longer. (This is not causation, it's just an interesting tidbit).

- Thu Apr 29, 2010 1:23 pm UTC
- Forum: Science
- Topic: People who just don't get it
- Replies:
**23** - Views:
**2825**

- Wed Apr 28, 2010 7:32 pm UTC
- Forum: Science
- Topic: How do we capture solar energy?
- Replies:
**14** - Views:
**1874**

### Re: How do we capture solar energy?

Connect either a capacitor bank, a battery recharghing facility, or a hydrogen lysing plant to the solar array.

- Tue Apr 27, 2010 5:16 pm UTC
- Forum: Mathematics
- Topic: First Math Paper
- Replies:
**6** - Views:
**1318**

### Re: First Math Paper

jaap wrote:Are you sure it's not simply that they want an anonymised version of your paper that they can use for the peer review process?

I believe this is correct.

- Mon Apr 26, 2010 10:54 pm UTC
- Forum: Mathematics
- Topic: What kind of series is this and how does it work?
- Replies:
**3** - Views:
**839**

### Re: What kind of series is this and how does it work?

Thanks for the link, squareroot1, and thanks for the math, OverBored.

Hypergeometric series, eh. It always comes back to hypergeometrics.

Hypergeometric series, eh. It always comes back to hypergeometrics.

- Mon Apr 26, 2010 9:45 pm UTC
- Forum: Mathematics
- Topic: What kind of series is this and how does it work?
- Replies:
**3** - Views:
**839**

### What kind of series is this and how does it work?

Let's say I have a series of numbers, Z, such that:

[math]\frac{Z_{n+1}}{Z_{n}}=f(n)[/math]

Where f(n) is a polynomial function of n. What is this type of series called, and is there a way to calculate the nth value of Z?

[math]\frac{Z_{n+1}}{Z_{n}}=f(n)[/math]

Where f(n) is a polynomial function of n. What is this type of series called, and is there a way to calculate the nth value of Z?

- Mon Apr 05, 2010 2:11 pm UTC
- Forum: Individual XKCD Comic Threads
- Topic: 0723: "Seismic Waves"
- Replies:
**94** - Views:
**26835**

### Re: "Seismic Waves" Discussion

If nobody's pointed this out yet, this comic is actually a reformulation of the Huygens-Fresnel principle. Each point on the wavefront acts as the centre of emission for another wave!

- Mon Mar 08, 2010 5:54 pm UTC
- Forum: Mathematics
- Topic: Favorite math jokes
- Replies:
**1452** - Views:
**485184**

### Re: Favorite math jokes

dx/dy=0 in those parts

- Mon Mar 08, 2010 2:49 pm UTC
- Forum: Mathematics
- Topic: Favorite math jokes
- Replies:
**1452** - Views:
**485184**

### Re: What's the derivative of x?

e x is walking down the street and he sees a constant running towards him. "Help me" he says, "a differential operator is coming towards me." e x says "don't worry, he can't hurt me, I'll take care of him." e x walks up to the differential operator and confronts him. &q...

- Thu Feb 25, 2010 2:27 am UTC
- Forum: Mathematics
- Topic: Search strings for x^x
- Replies:
**4** - Views:
**1118**

### Re: Search strings for x^x

Is there a journal or a branch of mathematics that focuses on integrating unusual functions? By the way, if anyone is interested, the history and derivation are both given pages 46-51 in this book: http://books.google.ca/books?hl=en&lr=&id=QnXSqvTiEjYC&oi=fnd&pg=PP16&dq=The+Calcu...

- Mon Feb 22, 2010 5:42 pm UTC
- Forum: Mathematics
- Topic: Search strings for x^x
- Replies:
**4** - Views:
**1118**

### Re: Search strings for x^x

Oh I've got something up my sleeve.

- Mon Feb 22, 2010 4:44 pm UTC
- Forum: Mathematics
- Topic: Search strings for x^x
- Replies:
**4** - Views:
**1118**

### Search strings for x^x

I'm interested in reading up on some of the work that's been done concerning the function f(x)=x^x and its integral (The Sophomore's Dream). I'm wondering what search strings I should type into google scholar to help me find papers. The caret notation isn't used in formal work (I don't think), and i...

- Mon Feb 08, 2010 2:20 pm UTC
- Forum: General
- Topic: Sleep-time holodeck experiences
- Replies:
**3404** - Views:
**762712**

### I dream of Randall

I had a dream last night where Randall Monroe used my apartment for some kind of XKCD fan expo.

As a token of appreciation, he left me a nude picture of Gillian Anderson.

As a token of appreciation, he left me a nude picture of Gillian Anderson.

- Fri Jan 29, 2010 2:07 am UTC
- Forum: Mathematics
- Topic: Show us your articles! Or what's your Erdos number?
- Replies:
**187** - Views:
**272803**

### Re: Show us your articles! Or what's your Erdos number?

My first paper has been accepted, and it will give me an Erdos number of 7. I'm not sure that is the lowest I can get; my coauthor is not in the collaboration distance calculator so I had to investigate and find a link. I have an Erdos number of 5 if you count my undergrad thesis, or the footnote in...

- Sun Dec 20, 2009 10:41 pm UTC
- Forum: Science
- Topic: Monte Carlo master equation
- Replies:
**12** - Views:
**2058**

### Re: Monte Carlo master equation

Check it out!

- Sun Dec 20, 2009 4:49 pm UTC
- Forum: Mathematics
- Topic: Question about Logarithms & Pi
- Replies:
**9** - Views:
**1690**

### Re: Question about Logarithms & Pi

You must have rounding errors.

- Wed Dec 16, 2009 3:45 am UTC
- Forum: Science
- Topic: The nature of gravity and spacetime
- Replies:
**19** - Views:
**2350**

### Re: The nature of gravity and spacetime

Spacetime isn't a fluid.

- Tue Dec 15, 2009 4:23 am UTC
- Forum: Science
- Topic: Monte Carlo master equation
- Replies:
**12** - Views:
**2058**

### Re: Monte Carlo master equation

Got my 1 and 2D simulations working. It's cool how you can see magnetization go towards +/- 1 over time, with fluctuations, and how the fluctuations depend on B.

- Mon Dec 14, 2009 9:18 pm UTC
- Forum: Science
- Topic: Monte Carlo master equation
- Replies:
**12** - Views:
**2058**

### Re: Monte Carlo master equation

Well it's for my master's research so the book might be useful.

That Landau gets his nose in everything.

That Landau gets his nose in everything.

- Mon Dec 14, 2009 7:14 pm UTC
- Forum: Science
- Topic: What's the difference between Physics and Chemistry?
- Replies:
**20** - Views:
**5715**

### Re: What's the difference between Physics and Chemistry?

Chemistry is the physics of electrons.

- Mon Dec 14, 2009 5:39 pm UTC
- Forum: Science
- Topic: Monte Carlo master equation
- Replies:
**12** - Views:
**2058**

### Re: Monte Carlo master equation

Eventually I want to be able to simulate polymer dynamics, but I'm working my way up from an easier system. Next step is 2D Ising.

- Mon Dec 14, 2009 4:49 pm UTC
- Forum: Science
- Topic: Monte Carlo master equation
- Replies:
**12** - Views:
**2058**

### Re: Monte Carlo master equation

Thanks guys. Removing Z gives decent sized probabilities, depending on how I fiddle with B. I'll play around with it. Metropolis algorithm is a good term to google, too.

I'm using the one true programming language.

MATlAB.

I'm using the one true programming language.

MATlAB.

- Mon Dec 14, 2009 3:29 pm UTC
- Forum: Science
- Topic: Monte Carlo master equation
- Replies:
**12** - Views:
**2058**

### Monte Carlo master equation

I'm trying to teach myself the Monte Carlo method. I'm programming a one-dimensional Ising simulation. I create a configuration of spins, and calculate the energy by multiplying nearest neighbors. Instead of calculating the partition function explicitly, I just take Z=(2*cosh(BJ))^N+(2*sinh(BJ))^N, ...

- Tue Dec 08, 2009 3:03 am UTC
- Forum: Science
- Topic: Something I've never understood
- Replies:
**24** - Views:
**3034**

### Re: Something I've never understood

Pretty much.

- Thu Dec 03, 2009 7:56 am UTC
- Forum: School
- Topic: Careers in Physics?
- Replies:
**10** - Views:
**1637**

### Re: Careers in Physics?

I worked for a year in an experimental ultrasound lab studying bubbles after I graduated.

- Tue Nov 10, 2009 12:29 am UTC
- Forum: Science
- Topic: I have some sulphuric acid. What do?
- Replies:
**31** - Views:
**5214**

### Re: I have some sulphuric acid. What do?

If you get some nitric acid you can mix them to make aqua regia, which can dissolve gold.

- Tue Nov 10, 2009 12:25 am UTC
- Forum: Mathematics
- Topic: Linear Algebra - Should I take it?
- Replies:
**8** - Views:
**1785**

### Re: Linear Algebra - Should I take it?

If you end up doing anything MRI related you'll need to know your linear algebra.

- Sat Nov 07, 2009 10:04 pm UTC
- Forum: Science
- Topic: I have some sulphuric acid. What do?
- Replies:
**31** - Views:
**5214**

### Re: I have some sulphuric acid. What do?

ASSUMING YOU HAVE PROPER SAFETY EQUIPMENT AND KNOW WHAT YOU'RE DOING mix it with sugar.

- Fri Nov 06, 2009 12:41 am UTC
- Forum: Mathematics
- Topic: Help with trig identities
- Replies:
**8** - Views:
**817**

### Re: Help with trig identities

Do you know a relationship between sin^2 and cos^2?

- Wed Nov 04, 2009 2:17 am UTC
- Forum: Mathematics
- Topic: Inverse of y=sinx +3x
- Replies:
**9** - Views:
**6713**

### Re: Inverse of y=sinx +3x

I don't think there's an analytic function for this, it'd have to be done numerically.

- Tue Nov 03, 2009 11:59 pm UTC
- Forum: Logic Puzzles
- Topic: Can you break my code?
- Replies:
**17** - Views:
**3975**

### Re: Can you break my code?

I think it's "a shatter'd visage"... although "as hat terd" is totally reasonable. :) Good poem , by the way. By the way, the cipher you used is equivalent to a Vigenère cipher with a keyword of ABCDEFGHIJKLMNOPQRSTUVWXYZ. Actually, for me at least, saying you used a...

- Tue Nov 03, 2009 8:23 pm UTC
- Forum: Logic Puzzles
- Topic: Can you break my code?
- Replies:
**17** - Views:
**3975**

### Re: Can you break my code?

HIHOWAREYOUDOING

codes to

IKKSBGYMHYFPBWCW

That should help.

codes to

IKKSBGYMHYFPBWCW

That should help.

- Tue Nov 03, 2009 4:11 am UTC
- Forum: Logic Puzzles
- Topic: Can you break my code?
- Replies:
**17** - Views:
**3975**

### Re: Can you break my code?

Did nobody reply because it's too hard or did nobody reply because nobody cares?

- Mon Nov 02, 2009 2:44 pm UTC
- Forum: Individual XKCD Comic Threads
- Topic: 0657: "Movie Narrative Charts"
- Replies:
**337** - Views:
**147773**

### Re: "Movie Narrative Charts" Discussion

There's an error on the Lord of the Rings graph.

Saruman (and possibly Grima, I forget) lived on and corrupted the shire and turned in communist, until getting arrowed.

Saruman (and possibly Grima, I forget) lived on and corrupted the shire and turned in communist, until getting arrowed.

- Sun Nov 01, 2009 7:30 pm UTC
- Forum: Logic Puzzles
- Topic: My write-up of the "Blue Eyes" solution (SPOILER A
- Replies:
**1368** - Views:
**418674**

### Re: My write-up of the "Blue Eyes" solution (SPOILER A

Can somebody explain to me what information the Guru gives, if everyone can already see someone with blue eyes?

- Sat Oct 31, 2009 4:02 pm UTC
- Forum: Logic Puzzles
- Topic: Can you break my code?
- Replies:
**17** - Views:
**3975**

### Can you break my code?

I came up with this code when I was bored and wrote a little program to implement it. Can anyone break it? I'll post a large passage in coded form. If it's still too hard I'll post some phrases with their coded versions, or something like that. The uncoded version of the following is in all caps, wi...

- Wed Oct 28, 2009 9:05 pm UTC
- Forum: Mathematics
- Topic: Is Pi Infinitely Long?
- Replies:
**57** - Views:
**5625**

### Re: Is Pi Infinitely Long?

If pi was a fraction then you'd get a contradiction.