Books about the history of physics

Books about the history of physics.

Watching Cosmos (2014) has rekindled my interest in physics and the history of physics.

Understanding Physics by Isaac Asimov

The Evolution of Physics by Einstein & Infeld

Six Easy Pieces and Six Not So Easy Pieces by Richard Feynman, also the complete Feynman Lectures on Physics are available online, as are his messenger lectures.

Visual Proofs



Sometimes, a visual proof is more helpful than pages of computations. Here are two interesting math concepts which you might find interesting.

1. "Dual" of polyhedra -- basically take a solid like a cube, find the midpoint of each edge, and rotate each edge about the midpoint until it connects with the other sides. Those two shapes are "dual". http://hyrodium.tumblr.com/post/76098308148/dual-polyhedrons

2. The "Sum of squares" 1 + 2 + 4 + 9 + 16 + ... has an elegant representation. Just think about stacking blocks and count up how many blocks are in the solid rectangle when you're done:
Proof 1 - fantastic animation! (source) Here is a Non animated 2d proof.

Linkdump from today's explorations

Investement simulator
http://www.cfiresim.com/input.php?id=89449

From this thread

187 million taxi rides

2013 taxi data from NYC yields some interesting insights.
https://www.mapbox.com/blog/nyc-taxi/

The discussion on hackernews was interesting. https://news.ycombinator.com/item?id=7926358 and revealed some fascinating insights. The current top comment offers some insights into how this data could be manipulated to find out, say, who is attending what bars and when... https://news.ycombinator.com/item?id=7927034

Reddit also picked up some interesting bits of info from the data including what percentage of people tip, and how much: http://www.reddit.com/r/bigquery/comments/28ialf/173_million_2013_nyc_taxi_rides_shared_on_bigquery/

89,092,521 (47.57%) left no tip, but... "Cash tips are easier for cab drivers to "forget" to report, so even though data suggests people tip more when paying by card (where the tip presets start at 20%!), drivers still prefer an under-the-table tip."

From the reddit thread, someone linked a detailed yet approachable article about how the data may not be very anonymous: https://medium.com/@vijayp/of-taxis-and-rainbows-f6bc289679a1

> It took a while longer to de-anonymize the entire dataset, but thanks to Yelp’s MRJob, I ran a map-reduce over about 10 computers on EMR and had it done within an hour. 

Interesting stuff!

Properties of 8675309

Aside from being a catchy tune, 8675309 is an integer with some interesting properties. The fact that is is a primitive Pythagorean triple is remarkable!  

A wolframalpha query yields these results:

Snopes article about how this song caused (or didn't cause) havoc for phone companies...

The song:

How to make online learning succeed

Below are some general guidelines about how to make an online course work best for reasonably responsible high school students. An important philosophical belief I have based on my experience with both in-class and online learning is that "technology is a tool" and like any other tool it takes consistent practice to master and it may not be perfectly suited for every single person. It can be made to work reasonably well for almost everyone if the following guidelines are kept:

Good practices
1. There must be regular (once-per-week minimum) communication between the student, online instructor, and in-school contact.

2. The student is expected to:
2a. spend roughly 1 hour/day, 5 days/week, every week on coursework (reading the text, regularly accessing the website to see videos, notes, try problems, email instructor, etc.)
2b. ask questions as soon as a problem (tech, math, etc.) arises!

3. The student should be provided with a quiet place to work on the course. (library, quite time at computer lab, etc.)

4. Logistically speaking, tests are 90 minutes, on paper.  The student will need space, time, and a proctor for these tests. Midterm & Final = 180 minutes. Returning the tests is easy as using a smartphone or scanner to turn them into PDFs. * Note -- These times are specific to my courses. Your mileage may vary.


Here is how students often ... don't find success:

Bad practices
1. Students don't interact with the instructor regularly. Students don't have any sort of at-home or in-school person to check in on them weekly.

2. Students do the following:
2a. Spend 0 hours on the course for 2 consecutive weeks, then try to cram 10 hours into a weekend.
2b. Do not let the online instructor know when something is wrong (tech,math, etc.)

3. Students try to do their coursework in loud or distracting environments.

Myself and my team of instructors will continue to check in with the student and instructor throughout the enrollment, but the expectation is that the student is keeping to the suggestions above. Sometimes he or she may veer off course -- that's human, it happens, and it can easily be fixed if it's caught quickly.

Euler and more

Today's Mathematical Explorations. 

"Read Euler, Read Euler, he is the master of us all."

How to lie with dataviz: http://data.heapanalytics.com/how-to-lie-with-data-visualization/

Frequency Spectrum of sounds. (PDF)
Two letter combinations in English. http://mechanicalscribe.com/notes/most-common-two-letter-combinations/
Statistical analysis of Bob Ross's works: http://fivethirtyeight.com/features/a-statistical-analysis-of-the-work-of-bob-ross/
Depth of the ocean -- why it's difficult to find sunken black boxes. http://apps.washingtonpost.com/g/page/world/the-depth-of-the-problem/931/

Inequality in golf. And a relevant image (source)


A lexicon of common math mistakes.

Hundreds of pages of notes from Feynman.

Your weight in outer space.