A live 4D scene, seen from a camera that follows the subject: a humpback whale spirals down toward a black hole, over a glowing accretion disk whose image bends around the black shadow. Past moments of the whale stay drawn as pale copies along its spiral, about one for every body length she swims, and the present is outlined on top of them. The fall loops on its own. Scrolling down draws the camera back until the whole spiral is in view, then carries the fall to its last frame before the page moves on; scrolling up reverses it. A pinch, or the plus and minus keys, bring the camera closer or farther. The scene is synthetic.

Whale fall.

A humpback computed from equations spirals into a black hole. Every moment of the fall stays on screen. synthetic

CH 1 Your time t

00.00s

CH 2 Its time τ

00.00s

Lag
0.00s
r/rs
7.000
dτ/dt
0.926
z
0.080

Acquiring

Tracing the fall…

0%

Time
Colors
Layers
CH 3 Tail beat

Heard from far away. Time runs down.

00:00:00
HOLD 0.00×

Two clocks,
one fall.

A humpback whale, computed from equations, falls toward a black hole. Far away, you keep one clock. She keeps another. Close to the horizon hers runs slow, so every second of yours carries less and less of hers, and every moment of the fall stays drawn where it happened.

Gravity bends time.

CH 1–2 Clocksr/rs 7.00

One tick per second of each clock. Each line joins the same count.

The whale’s clock ticks at dτ/dt = √(1 − rs/r) of yours. At 7.00 Schwarzschild radii it keeps 92.6% of your pace. By the last frame it keeps 35.2%.

Over the 15.0 seconds you watch, she lives 10.1. Nothing on her side feels slow: her tail beats once every 2.0 seconds of her own time, all the way down.

Every orbit, one plate.

Plate From abover/rs 2.72

The whole fall seen from above: 1.40 turns, one copy of the whale every 0.40 seconds, spiralling into the black shadow at the centre of the disk. Near the horizon the copies crowd together.

First 3 s
8.4cm/frame
Last 3 s
1.7cm/frame

Redshift.

CH 4 Lightr/rs 1.50

CH 4 Wavelength reaching you. Time runs down.

Light climbing out of the well arrives stretched by 1 + z = 1/√(1 − rs/r). The band on the left is what the whale reflects between 380 and 780 nm, one row per frame. By the last frame it reaches you 2.8 times longer, from 1075 to 2208 nm: none of it is visible any more.

The reds on screen stand in for light your eye could no longer see.

  1. f 000z 0.08

  2. f 225z 0.40

  3. f 449z 1.83

The last frame never arrives.

CH 5 Depthr/rs 1.14

CH 5 r/rs from 7 to 1clip endsframes that never come

The path is chosen: r = rs(1 + 6e−t/4) comes closer to the horizon with every frame and never reaches it in your time. The clocks are computed. Her last frame carries 0.012 s of her time; the next would carry less, and the one after that less again.

In her own time the same fall adds up to 13.0 s. You could wait forever. She would not.

From the pack.

CH 1–5 Packr/rs 1.14

Frames
···
Duration
···
Frame rate
···
Moving points
···
Still points
···
Weight on disk
···

Read from the pack currently loaded, not typed by hand. The scene is synthetic: the whale, the disk and the stars are computed from equations, with no third-party model, and baked into points frame by frame.

The lens behind them is traced live in your browser, one ray per display pixel.