[imtringued]

You are right. Money without depreciation violates the second law of thermodynamics and hence it is a Ponzi scheme in a physical world. This also includes any gold based money.

There can be no economic perpetuum mobile in the real economy on earth because humans need food which is produced by growing plants which capture sunlight.

Gold will be there long after humans have gone extinct. That violates the concept of a store of value. It means that gold doesn't store any value. It means humans delegate the storage of value to each other by utilizing gold and in that respect it is identical to fiat.

The property that fiat and gold have in common is the lack of holding costs that anything including the human body has in the real economy.