There's no duplication involved. It's an immutable database with an eavt (entity, attribute, value, time) index model. Pick a point in time to filter entities e

There's no duplication involved. It's an immutable database with an eavt (entity, attribute, value, time) index model. Pick a point in time to filter entities existing only at that point. It's effectively a read-only pointer to the full db created for free after every transaction.