# What will happen to the entropy in a universe made out of antimatter? [duplicate]

The second law of thermodynamics states that;

The total entropy of an isolated system can only increase over time or it can remain constant in ideal cases where the system is in a steady state (equilibrium) or undergoing a reversible process. The increase in entropy accounts for the irreversibility of natural processes, and the asymmetry between future and past.

So if there was a universe made up of antimatter will the entropy of that universe increase or decrease?

Because according to my research;

The Feynman–Stueckelberg interpretation states that antimatter and antiparticles are regular particles traveling backward in time.

Will the entropy of a universe made up of antimatter increase or decrease? Or is there any possibility that there can be a universe made up of antimatter because the entropy always increases by time? And what will happen to such a universe assuming that the entropy decreases? (because antimatter travel backward in time)