Can a primordial soup close itself into a vesicle?

A coarse-grained soup of monomers on the GPU, pass criteria fixed before the runs, and a negative answer with a measured cause: the aggregate grows, but it never traps water.

Three snapshots: an early soup with 316 amphiphiles in 270 clusters; the same periodic box at step 148,200 with one aggregate that wraps all three axes; a finite water parcel with one aggregate that wraps none. None traps water.

What was measured

  • No closed vesicle formed in any snapshot of any campaign.
  • In a 76 σ periodic box with 483,268 particles, one aggregate collected 99.93% of the amphiphiles, wrapped through all three axes in 23 of 23 wet snapshots, and trapped no water.
  • Four explanations were tested and ruled out: too much material, edge energy, weak head repulsion, box size.
  • In a finite parcel of water the aggregate stopped wrapping (0 of 3 axes) and still trapped no water, so the periodic boundary was not the cause.
  • What is left is the molecule: in a finite region a capped micelle costs about 19 amphiphiles and a closed vesicle about 990, and a measured acid–soap pair between heads did not close that gap.
  • What agreed with the literature: bilayer area per lipid 1.1734 σ² and thickness 4.4689 σ in explicit water, and the salt shift of the apparent pKa, +0.709 against about 0.7.
The periodic campaign from step 3,000 to 148,200: small clusters, a dry phase, then one sheet through the whole box.

Rules the project held itself to

Gates before runs. Every claim has a model value, a literature corridor, a verdict and an evidence rank, and a gate is never widened to pass.

No tuning toward the answer. The bond attempt rate is not adjusted to get a result, and the engine reads every chemical constant from data files.

Emergent hydrophobicity. It has to come from water displacement, never from a direct attraction between tails.

Silent failures are findings. Six failures that looked like success are documented, each with how it was caught.