According to our current understanding of physics, specifically within the framework of Einstein's theory of general relativity, there is no known way to travel backward in time.
Time travel to the past, often referred to as "backward time travel," would involve moving or experiencing events in a direction opposite to the normal flow of time. However, numerous theoretical and practical challenges arise when considering the possibility of such travel.
One significant challenge is the violation of causality, which refers to the idea that an event in the future can affect its own past. If backward time travel were possible, it could lead to paradoxes and contradictions. For example, the "grandfather paradox" suggests that if you were to travel back in time and prevent your grandparents from meeting, you would create a contradiction because you would not exist in the future to go back in time in the first place.
Various theories have been proposed to reconcile the concept of time travel with known physics, such as wormholes, cosmic strings, or exotic matter. However, these ideas currently remain purely theoretical and speculative, lacking empirical evidence or a comprehensive understanding of their implications.
It's important to note that scientific knowledge is not static, and our understanding of the laws of physics may evolve over time. Future discoveries and breakthroughs could potentially introduce new possibilities or challenges related to time travel. However, as of now, traveling backward in time without changing anything or meeting your former self is not considered feasible within the bounds of our current scientific understanding.