```                  CHARLIE
Muzzle velocity?
(off Don)
Of an... M1A1?

DON
I dunno -- 7-800 --

COLBY
853 meters per second. Effective
range of 460 meters --

CHARLIE
Accounts for a roughly --

MORE GUNSHOTS -- one of the SUV windows shatters -- as
Charlie checks his watch as the reports reverberate --

CHARLIE (cont'd)
-- quarter second delay...
```

# Flash Bang Thwack »

You are standing near a target. You see a flash as a gun is fired. Later, you hear the sound of the gun. Finally, you see the target get hit. The delay between these events is determined by the distance of the shooter and the velocity of the bullet. Here, a rifle bullet is used, with a velocity of 150 meters per second. A pistol often has twice that velocity, and an assault rifle four times that speed.
```RESUME Charlie dictating... looking at a PICTURE OF THE
PARTHENON.

CHARLIE
My mother had this photo of the
Acropolis... from a trip she'd taken
with my father, before I was born.
(beat)
One day, I scribbled all over it with
a crayon. She was understandably
upset -- until my Dad pointed out
that I'd covered it with rectangles
within rectangles -- retracing the
Greeks' use of the Golden Ratio.
```

# Golden Spiral »

This Demonstration draws an approximation to a golden spiral using a golden rectangle.
```Larry's PHONE BEEPS -- he reads a text.

LARRY (cont'd)
That's Charlie asking for assistance
with some aperiodic tiling. You want
to come with?

AMITA
(pause)
Actually, I have some low density
parity check code that isn't writing
itself.
```

# Robinson Tiling »

Aperiodic tiling showing hierarchical structure, published by Raphael M. Robinson in 1971.
```                  LARRY
Raspberry seeds are arranged on a
Fibonacci sequence, aren't they....
```

# Phyllotaxis Spirals in 3D »

In almost all above-ground growth in plants, new sprouts come out at angles of about 137.5° relative to the previous one. But between each sprout, the main stem or trunk has grown different amounts. See the effect this has on the overall form.