Mooncakes, Suncakes

The upcoming Mooncake Festival has me thinking about lunar calendars again.

All civilizations eventual commit to either the solar calendar (where the revolution of the Earth around the sun is primal and the Moonths just fit in as they can) or the lunar calendar (where 'years' are always a integer number of lunar revolutions (usually 12 or 13)). Since the Chinese and Islamic holidays are on a lunar schedule they do not occur at the same point every year on the solar calendar. The Chinese calendar cheats with intercalary days to keep it relatively even with the solar year. Of course if I'm going to call that cheating then we have to call leap years and leap seconds (added to solar calendars to keep the 24 hour day in line with the solar year) cheating too!

This is all beside the point - what is on my mind is writing language right to left versus left to right. It seems like there is a correlation between lunar calendar cultures and writing right to left versus solar calendar countries writing left to right. My cursory research reveals no definitive answer why some cultures settled into left to right versus right to left. I am fairly positive there is no real correlation with writing and the calendar choice but I want there to be one so I post this anyway...

Physics Rap in Progress

Going from the D to the V to the A
Kinematics, that’s what I say
Those equations be child’s play
Thinkin’ with my noggin, the price I pay

Finding rise over run so patiently
Tracking units so diligently
Doing Calculus conceptually

You outside – jumpin’ rope
I rhyme physics – really dope
Ya’ll mopes, just take them slopes!

Finding rise over run so patiently
Tracking units so diligently
Doing Calculus conceptually

Up & down graphs I pantomime
Areas under curves have a sign
Vectors or scalars – I don’t mind

Finding rise over run so patiently
Tracking units so diligently
Doing Calculus conceptually

Goodnight, Water Dumplings, and Neuroscience

I was trying to get Sebastien to say "go to bed"(shui jiao) in Chinese for his grandparents (I thought it meant 'goodnight'), but he was uncooperative and the grandparents just started laughing at me. I asked what was so funny and they said I was saying "water dumpling" (shui jiao). It turns out that in Chinese, an emphasis on a different part of an otherwise identical sounding word can mean an entirely different thing. Even after several repeats of the two variations, I couldn't really tell the difference.

(image from http://www.worldfoodieguide.com)

As a baby learns, it turns out they are mostly pruning connections from their brain. A baby's apparent confusion and inability to parse the world is due to an over-connectedness of neurons in their brain. For this reason, if a baby in not exposed to certain sounds from a language at an early age, it will be extremely difficult for them to ever speak that language as a native speaker would. Certain connections within the brain would have already been deemed not useful and severed, making it difficult afterwards to differentiate those foreign sounds.

As a baby I was filled with potential and could differentiate between water dumplings and going to bed, but, in a quest for simplicity, I lost my way...

My Friend Chuckles

When I was in high school, my math teacher said something like "figure this out" but, for some strange reason, I though he said "big fat jerk." Since I felt pretty comfortable in his class (we called him 'coach' since he sponsored the Math Team), I blurted out "Did you just call me a Big Fat Jerk?" He paused - looked confused and then started to laugh. The rest of the year he would affectionately call me "BFJ".

Years later in college, some of us were trading misunderstood lyrics in the dorm and all agreed our favorite was Jimi Hendrix's "Excuse me while I kiss this guy."

Last year in school I was telling a story about Ton-Ton Roger ("My French Uncle") to one of my classes. Perhaps it was the one where he had turned his car window washers out 90 degrees in order to spray pedestrians on the sidewalk (he had replaced the window washer fluid with plain water). Or maybe it was the one where I was trying to hide the fact that I had been dangling a winery employee by the feet into a fermenting vat of red wine to retrieve my glasses. Or maybe it was the one about the rat in the Chardonnay. Who knows... the point is, at the end of my story, one kid turns to another and says "Who's his friend 'Chuckles'?

MCAS and Slippery Statistics

Scot Lehigh had an interesting editorial recently in the Boston Globe defending the MCAS (Massachusetts Comprehensive Assessment System, the required-for-graduation standardized test). He cites some interesting statistics comparing how well current students (class of 2011) are doing on the MCAS compared to the class of 2003. He, like almost everyone, compares the scaled scores of the MCAS which has cutoffs for being “Advanced”, “Proficient, “Needs Improvement” (but passing), and “Failing”.

The problem here is that the MCAS is a moving target; to be proficient this year only required a raw (unscaled) score of 47/72 on the English portion, but in 2003 you needed a 52/72. To pass, the cutoff has been lowered from 2003’s 38/72 to today’s 31/72 (that's a 43 % to pass!). By moving these cutoffs around and changing the content of the questions on the test, the MCAS can make public schools look great or lousy at will.

Here are some specific statements in his piece that I take issue with:

"Teachers, too, have stepped up...overall they've done a good job helping students master the required material." Good performance on a test is frequently simply a reflection of good prep for that particular test, not necessarily an indication of mastery of the subject material.

“When the MCAS actually started to count, the passing rates went up dramatically.” I personally have seen the MCAS given to students for whom the test does not count: they make pretty designs on the answer key, they purposely try to get the answers all wrong (surprisingly hard to do), they answer all ‘C’, or they simply leave the entire test blank, etc. No surprise to me that the score on any test taken by teenagers goes up when “it counts.”

“Since we’ve implemented high standards here [meaning MCAS], Massachusetts students… have been turning in top-notch performances. That’s just more evidence of the value of strong curriculum frameworks and standards” What’s the ‘more evidence’? If there is improved MA performance on national assessments post-MCAS then that would be something, but improving MCAS scores is just inside baseball.

On the recent poor results on the Science MCAS: “To some, that may mean delaying or lowering the new standard. That, however, would be precisely the wrong reaction.” Lowering the standard is exactly what the state did (see my second paragraph) when it became a real possibility that thousands of otherwise eligible high school students would be denied graduation because of a poor English MCAS score.

Fires, Flux, and Wintertime

It is one of the more commonly known confusions in Science: The Earth is closest to the Sun in the wintertime (assuming you live in the northern hemisphere!) not when it is hottest. Of course, logic dictates that we can't be closer in the summertime because all the southern hemisphere folk are trudging through wintertime "down" there.

It turns out the proximity of Earth actually has nothing to do with the seasons. As you are taught in grade school, the perihelion and aphelion could occur anytime during the year and we wouldn't notice a difference - the reasons for the seasons is axial tilt. Most of us know this fact, but I'd wager most of us still picture it as a distance issue rather a tilt issue down in our guts. After all, if you are standing about 10 feet from a bonfire and take a few steps closer - you feel warmer. Take a few steps back and you cool off! We know this to be true by experience and we like to think of the Sun as a big fire in the sky. We know this simple fact to be true and so we keep coming back to it when thinking about heating up and cooling off.

(image from http://www.braintree.gov.uk/Braintree/default.htm)
I think one of the reasons for the persistence of science misconceptions in general is that we are not taught well. One must take the misconception head-on and run with it. Your science teacher should pursue this idea of getting closer to a fire: If the Earth -Sun distance was indeed 10 feet, then we could approximate the real change in distance during one orbital revolution by moving our face 2 inches closer to the bonfire. Not much of an effect, eh?

Now, watch the bonfire from 10 feet away and tilt you head back 23.5 degrees. Note the difference between your forehead (northern hemisphere wintertime) and your chin (southern hemisphere summertime). Your forehead is not cooler because it is further away, it is cooler because fewer rays of light are hitting your forehead now. This concept is called flux. Imagine putting your open hand in a waterfall, palm up. Now rotate your hand until only the edge of it is being struck by the waterfall. Your hand and the waterfall have not changed, but their relationship certainly has: you've gone from high flux to low flux.

(image from http://sol.sci.uop.edu/~jfalward/electricforcesfields/electricforcesfields.html)