The question of whether time travel can change the future is a topic of debate and speculation. According to our current understanding of the laws of physics and thermodynamics, the concept of changing the future through time travel faces significant challenges and paradoxes. Here are a few considerations:
Causality and the Grandfather Paradox: One of the most well-known paradoxes associated with time travel is the Grandfather Paradox. It posits that if you were to travel back in time and prevent your grandfather from meeting your grandmother, then your own existence would be paradoxical. The paradox arises when the effect (your nonexistence) contradicts its cause (preventing your grandparents from meeting). Resolving such paradoxes requires revisiting fundamental concepts of causality.
Consistency and Novikov Self-Consistency Principle: The Novikov Self-Consistency Principle suggests that any actions taken by a time traveler in the past must be consistent with the events that led to the time travel itself. In other words, if you were to travel back in time, any actions you take would already be a part of history and would have occurred in a way that does not create contradictions.
Time travel and thermodynamics: Time travel, especially into the past, often raises questions related to the second law of thermodynamics, which states that entropy (disorder) in a closed system tends to increase or stay the same over time. Some proposed scenarios of time travel involve reversing or violating this law, which raises significant challenges.
It's important to note that our understanding of physics and the laws governing the universe may evolve and change with future discoveries. The concept of time travel is still largely in the realm of speculation and remains a topic of scientific inquiry and exploration. there is no scientific consensus on the feasibility or practicality of time travel, nor on its potential to change the future.