# GOL-009: Duplex Life

Two independently ruled Life fields take alternating turns, each bending its neighbor count toward the newest state of the other through a tunable fractional influence.

[Open simulation](https://100gol.com/experiments/009) · [Directory](https://100gol.com/experiments)

## What to explore

The two layers must remain genuine stateful peers, not one real world plus a
predictor. Their alternating feedback should be visible in layer ages and the
next actor, and the default should demonstrate delayed entrainment without
collapsing into exact identity or extinction.

## Rules, update order and replay

Two aligned square binary Moore lattices retain independent B/S masks, starts,
seeds, densities, and ages. One Step updates only the active layer, beginning
with Layer 1. Within that turn, every cell reads one frozen active-layer board
and the newest committed other layer. Its raw count is its eight same-layer
neighbors plus 0, 25, 50, 75, or 100 percent of the other layer's aligned eight
neighbors; the aligned center is excluded. Counts use integer quarter-points.
Nearest-integer conversion is fixed except exact halves, which use the explicit
up/down control. The active layer commits synchronously, then control alternates.
Replay requires both boards, ages, active layer, topology, all masks, coupling,
half-tie mode, profiles, and both seeds/densities or starters. Reset rebuilds
both fields and restores Layer 1 as first mover.

## Reading the simulation

Composite view uses lime, violet, and pale overlap; single-layer views remain
available. The selected-cell inspector chooses a layer, marks same-layer and
cross-layer inputs differently, and reports both integer counts, raw
quarter-weighted total, exact-half status, effective count, B/S match, next
state, and whether that layer acts next. Layer ages and next actor remain visible
in text, so neither alternation nor overlap depends on color alone.

## Reproduce a starting configuration

[Download example JSON](https://100gol.com/api/experiments/009/configuration). Import it using Share & reproduce in the simulation controls. It starts paused at Step zero. Files contain rules and initial conditions, not evolved boards or manual edits. See [format, limitations and automated access](https://100gol.com/agents).