Every square is a magnetic spin. Drag the temperature: hot and they churn, cold and the pattern freezes in place.
What the machine is doing
The lattice is 16×16×16 sites, and the device holds 4,096 independent copies of the whole thing at once — one per bit of a wide register. A single instruction updates a site in every copy simultaneously.
That is the point of the picture. One sweep of the cube is 4,096 site updates and about 460,000 wide instructions, and those instructions between them touch 16.8 million spins. A processor with 32-bit registers would need 128 operations where this needs one.
You are watching one copy, one layer — a 16×16 window onto a machine that is running 4,096 of these in parallel.
Why it does not turn one colour
This is a spin glass, not a fridge magnet. The couplings between neighbouring spins are random: some pairs want to agree, others want to disagree, and no arrangement satisfies all of them. Cooling it does not line the spins up. It freezes — the pattern stops changing while staying scrambled.
That frustration is exactly what makes spin glasses hard, and why physicists simulate them by the millions. What to watch is whether the picture is still moving, not what colour it is. The magnetisation readout sits near zero at every temperature for the same reason.
What this does not tell you
Nothing about speed. The processor here is a software model running in your browser, so how fast it goes is a property of your laptop rather than of Sparsr. The instruction and spin counts are exact; there is deliberately no timing figure beside them.
The Monte Carlo update itself is not written for this page — it is the same kernel the cheminformatics and statistical-physics work uses, compiled by the ordinary RISC-V toolchain and shipped here as 340 bytes of instructions.