A View from the Back of the Envelope top

Developing "deep" understanding
Deep understanding
Rough Draft

practice - make it frequent and fun

How to develop?

Practice and seek out good descriptions.

Good descriptions

Seek out Good descriptions, to tell of what is going on, and which of it is important.


Fermi Questions

Practice with Fermi Questions
and Knowledge you can work with...

Visualization and imagination

Scaling the universe to your desktop
Picturing altitude above maps
Probing near space with a flashlight.
Generating questions by teleportation.
Where is China? (or Antarctica, or...) It is down over there... Looking down, through the earth, at the rest of the globe.
A car trip to the earth's core.

Links to model solar system resources
The relative size of Earth, Jupiter, Sun (1 : 10 : 100)

Integrating measurement into your life

measuring angle&distance with your thumb

Breadth, and a sense of what is reasonable

Scale of some things and `Powers of Ten'ish scales.
Scaling the universe to your desktop
Getting a feel for big numbers


Choosing good units
Measuring geologic time in earth-orbits-galaxy years.
And perhaps Order-of-magnitude calculation - a "you are already doing it" introduction

Atomic bonding (is fundamentally a balance of attraction (electrostatic) and repulsion (electron-compression).)

A View from the Back of the Envelope
Comments encouraged. - Mitchell N Charity <mcharity@lcs.mit.edu>

Fundamentally, integrate a thoughtful, approximate, numerate thread into your life.

 2002-Apr-11   Changed links (evacuating www.tiac.net).
 1997.Aug.01 - First draft, from notes formerly in `Deep understanding'.
  what of this is key
  what if ...
  if that ... then ...
  look at in a different way
  scale mixing (pet the cat-sized ant on your lap)
[i/o boxes | Feynman learning fuzzy concept story | ]

Robert Romer's "Qualitative Questions" AmJPhys64(7)1996July
[scale models]
[redistributions blood/gold/oil]
[BotEnvelope provides enough leverage for you to integrate into your life the asking and answering of questions.]

[time: heart-rate clock, oom 1sec/beat, min/max 50/200 bpm, .3-1.2 sec/beat, 100+-x2 bpm, good(80bpm) is 3/4 s/beat, contrail-angle-time-altitude calc | reflex calib]

  From  Examples to use in intro biology:
I have relied on DAvid Letterman's Stupid Human tricks a lot to show 
anatomical features i.e the man blowing cigarette smoke out of his 
ear, another man "drinking" milk through his nose and squirting it out
of his eye, the girl who pushed her tongue behind her uvula and into 
her nasopharynx, are all clips I have used. It really gets the class 
david woodman