The prime launches a wave — Flow Lenia causal-echo tomography

01 / What the movie revealed

The response changes layer and direction.

We compared the native causal contrast left by a 0.5× prime with the same contrast left by a 4× prime. The purple trace is the dense-core response minus the surface response. It turns negative, then returns strongly positive. Nothing is driving the system during this movie.

Early → turning

+3.80 [+1.38, +6.37]

Change in the dense-core contrast. Seven of eight organism families move in the same direction.

Inverted → re-expressed

+4.09 [+0.54, +8.18]

The dense-core response returns later. Again, seven of eight families agree.

Surface keeps moving

-1.82 [-2.77, -0.91]

Late surface change. All eight families move negative even as the core response returns.

The body is not relaxing back along one line. It is moving through a sequence of causal states: early core expression, inversion, core re-expression, then surface/core separation.

02 / The body carrying the memory

Subtle in pixels. Large in causal organization.

These are one representative organism at three phases. The visible shapes remain recognizably the same creature. The strongest difference lives in how connectivity is distributed across density thresholds—not in a dramatic mass gain or obvious morphological rupture.

Source 25, 0.5 dose, 16 unforced steps — **0.5×** · early · step 16

Source 25, 4 dose, 16 unforced steps — 4× · early · step 16

Source 25, 0.5 dose, 64 unforced steps — **0.5×** · inverted · step 64

Source 25, 4 dose, 64 unforced steps — 4× · inverted · step 64

Source 25, 0.5 dose, 144 unforced steps — **0.5×** · re-expressed · step 144

Source 25, 4 dose, 144 unforced steps — 4× · re-expressed · step 144

That matters. The memory is not a scar we can point to as “extra material here.” It is a change in how the same body is internally organized and therefore how it will answer the next perturbation.

03 / A physical lead on the causal echo

Component spacing follows the later response curve.

Across the five previously measured gap durations, the low-dose-minus-high-dose native component-spacing state follows the shape of the later dense-versus-surface response: temporal correlation 0.866. After removing average family and time effects, the association remains 0.442.

This is a lead, not a finished clock: it was selected from the physical-state scan after seeing the response curve. But it tells us exactly what to do next. Stop perturbing at arbitrary elapsed times. Ask the body when its own state says it is ready.

04 / Next direct swing

Trigger the perturbation from the body, not the stopwatch.

The next experiment will prospectively compare state-triggered interventions with time-matched controls. If the body’s component-spacing and density-depth state predicts which layer answers next, then causal susceptibility is a physical phase of the organism—not just a function of age.

Prime fresh organisms once and monitor the two candidate coordinates: component spacing and surface-to-core topology.

Apply the second perturbation when the state enters a frozen “echo-ready” region, while a matched control receives it at the same elapsed time without state selection.

Measure whether state-triggering increases the expected dense-versus-surface response and whether the same physical phase generalizes across new bodies.

The emerging picture: information geometry does not only push morphology. It can launch an internal developmental trajectory whose future causal meaning depends on where the body is along that trajectory.