Friday, June 6, 2014

Chess in "Donald in Mathmagic Land"

In the Disney short "Donald in Mathmagic Land," Donald watches a game of chess. This is supposed to show how math is used in an everyday setting.
The game is shown without players, pieces moving on their own through stop motion. The game is played rapidly, lasting only about 24 seconds. In order to finish the game in such a short time, some moves begin to take place before the previous ones have finished.
The game begins as the Blackmar Gambit, but quickly devolves into a shallow novice game designed to remove pieces as quickly as possible rather than exhibit strong play. The simple discovered check in 16...Nc5+ seems to have come as a complete surprise to white. It is a flurry of movement to entertain and impress the uninitiated, but it is useless for serious study. I record the details here for the curious.

1. d4 d5
2. e4 dxe4
3. d5 c6
4. dxc6 Qxd1+
5. Kxd1 bxc6
6. Nc3 Nf6
7. f3 exf3
8. gxf3 e5
9. Bh3 Bxh3
10. Nxh3 Bb4
11. Bd2 Bxc3
12. Bxc3 e4
13. Bxf6 gxf6
14. fxe4 Nd7
15. Nf4 O-O-O
16. c3 Nc5+
17. Kc2 Nxe4
18. Rad1 Rxd1
19. Rxd1 Nf2
20. Rd6 Kc7
21. Rxf6 Rf8
22. Nd5+ cxd5
23. Rxf2 Re8
24. Rxf7+ Kc6
25. Rxa7 Re2+
26. Kb3 Rxh2
27. a4 Kb6
28. Rd7 Rd2
29. Rxh7 d4
30. cxd4 Rxd4
31. Rh6+ Ka5
32. Rc6 Rd3+
33. Ka2 Kxa4
34. Rc4+ Kb5
35. b3 Rd5
36. Ka3 Rd8
37. Rb4+ Kc5
38. Ra4 Kc6
39. b4 Kb5
40. Ra5+ Kc6
41. Ka4 Kb7
42. b5 Ra8
43. Rxa8 Kxa8
44. Ka5 Kb7
45. b6 Kb8
46. Ka6 Kc8
47. Ka7 Kd8
48. b7 Ke8
49. b8=Q+ Ke7
50. Qe5+ Kf8
51. Qe6 Kg7
52. Kb7 Kf8
53. Kc7 Kg7
54. Kd7 Kf8
55. Qe7+ Kg8
56. Qf6 Kh7
57. Ke7 Kg8
58. Qe6+ Kh8
59. Kf7 Kh7
60. Qg6+ Kh8
61. Qg7#
The white queen is shown capturing the red king.

Sunday, January 26, 2014

Why Forward Must Be Up

When signs need to indicate a forward direction, they typically use an upward pointing arrow. "Forward" is actually perpendicular to the face of the sign, so an up- or down-arrow is equally wrong. However, roads leading away from you rise in your field of vision as they get farther away, so an upward vector is the more sensible choice.
I've wondered for years about the apparently arbitrary "up equals forward" convention, and I just today realized this satisfying explanation.

Sunday, October 30, 2011

The Parking Gods Reward Hubris

On Tuesday, I was exhausted. I had worked hard all day and only came back to my apartment for dinner. I still had a major project to finish and needed to go back to my office. Normally, I'm only too happy to walk to school since it only takes 15 minutes, provides the only exercise I get these days, and saves gas. This day, however, I felt I owed myself a ride.
Parking regulations in the lot next to the math building are only enforced until 6, so I could safely park in any spot. Even after hours, people seem to avoid parking in the spot reserved for the dean. Feeling a bit cheeky, I took it myself.
I worked long and hard on my project. As I left, security guards were prowling the building and there was a danger of tripping an alarm if I exited through the wrong door. I was pretty tired, so to keep from sulking over the sleep I had lost, I picked some cheerful music from my iPod for the walk home.
Walk home.
The significance of these last words did not occur to me until Saturday afternoon when I found that my truck was not parked in its usual spot by my apartment. A black horror overcame me as I realized that—in my exhaustion—I had forgotten that I needed to extract my vehicle from "Reserved for the Dean: $50 fine, towing enforced."
I trudged to the campus police office listening to the march from "1941"—normally a sure-fire way to cheer me up. Passing the math building, I noticed something odd: my truck was still parked in the dean's spot.
"Great," I thought, "so, instead of a single $50 ticket and a towing/storage fee I get three $50 tickets?"
I checked the wipers. No tickets.
"Then it's the boot! Oh, no! Anything but the boot!"
I looked down. No boot.
"So... do I just drive away?"
I checked the rest of my truck. Nothing out of the ordinary. I looked around for cops (sometimes they toy you by letting you think you've gotten away with it). There was no indication that my truck and I had violated anything.
Safely on the road home, I said a prayer of thanks. Specifically, I promised three of my first four children to any god that could prove his involvement, but suffice to say I was relieved.
Now, I happen to know several people who have been ticketed (or worse) for parking in that lot without a permit. They parked in the ordinary stalls (aware of the risks) and came back in a couple of hours only to discover that justice had been delivered in their absence. I parked in the prime location (flippantly enough that I forgot) and wandered back half a week later without consequences. Since every other factor is stacked in favor of my receiving a harsher punishment, I can only conclude that whatever forces guard wayward parkers are fond of my insolence, irony in general, or both.

Sunday, September 18, 2011

Presidential Consumer Review

I wondered today, what if we reviewed our elected officials like we review books, personal electronics and pet shampoos? Being the creative sort, I made up an answer:

Wednesday, August 31, 2011

Definition of Combinatorics

Those who study combinatorics are working to discover how many different ways they can suffer. The binomial coefficient that dominates their work is


.

This expression does not mean that I am over the pain. It is pronounced "I choose Pain."

Thursday, July 7, 2011

Gain and Loss

Everyone seems to believe that one man's gain must be another man's loss. The only exception they allow is government action in which case the poor gain and somehow, nobody loses. Well, maybe some rich pigs get taxed, but we hate them anyway.
Reality is precisely the opposite: unless coercive forces like the government get involved, people only interact by choice. Every exchange has expected gains for all parties. You can tell that they expected to gain because if someone expected to lose, they wouldn't have participated.

Tuesday, June 28, 2011

Subconscious

My brain comes up with some pretty weird stuff while I sleep, but this one is pretty interesting even a few hours after waking up. I dreamed that I was vandalizing a Port-a-John by writing on the wall:
Parapsychologists and parasitologists: one makes your ghosts flee, the other makes your fleas ghosts.