You cannot, it turns out, make more rock. Or even just melt it down, and then pour it into a mold to reshape it. Except volcanic glass. Other than that, the only rock we have is the rock we quarry. Unless we also have immense amounts of time. The eons (and pressure) required for molten rock to cool and form the crystals that characterize our granites.
If we cannot get our rocks — dumb, orderly, rocks! — back without time, tell me, why do you think we might get our life — complex, organic, perishable, life! — back without time?
Look closely at the bark of the Ginkgo and you will see that it is sterile. No ants run up it, and no mites live there, which is why cities, in search of trees that are immune to pests, love to plant Gingkos. The Gingko tree is no friend to life because it is a fossil, a perverse fern, in fact, that stopped evolving 200 million years ago, in an age before the dinosaurs. It survived by chance, sealed in some fold in the Chinese landscape, until it was brought forth and spread across a world of unfamiliar fauna by enthusiasts in the 19th and 20th centuries.
The creatures that grew up with the Ginkgo’s bark, and thought its stinking fruit perfume, are long dead. Today’s creatures grew up with other trees — the oak, the beech — and do not know what to do with a Ginkgo. What is missing is time. Give them a million years beside the tree, and they will adapt to it. But without time, that tree is as dead to them as concrete, plastic, or styrofoam.
The great obstacle to reversibility is time.