According to our current understanding of physics, the arrow of time and the increase in entropy are fundamental aspects of the universe and cannot be reversed in most circumstances. The arrow of time refers to the asymmetry we observe in the flow of events: time tends to move from the past to the future, and not the other way around.
Entropy is a measure of the disorder or randomness in a system. The second law of thermodynamics states that the entropy of an isolated system tends to increase over time. This increase in entropy is often associated with the irreversibility of physical processes.
While it is theoretically possible to encounter local fluctuations where entropy decreases temporarily (referred to as "negative entropy" or "negative entropy production"), these fluctuations are highly improbable and occur on very small scales. The overall trend, however, is toward increasing entropy and the irreversibility of macroscopic processes.
Reversing the arrow of time and decreasing entropy on a macroscopic scale would require overcoming a tremendous number of microscopic configurations and is not currently feasible with our understanding of the laws of physics. Some speculative theories and thought experiments, such as hypothetical processes involving the violation of fundamental symmetries or the use of advanced technology, have been proposed, but they remain highly speculative and unverified.
It's worth noting that the arrow of time and the increase in entropy are well-established observations in our everyday experience and are supported by a vast body of empirical evidence. However, our understanding of these concepts is still an active area of research, and future discoveries might bring new insights into the nature of time and entropy.