The notion that time travel does or does not result in changes to our timeline is a subject of speculation and debate, as it deals with concepts that are currently beyond our scientific understanding. However, based on our current understanding of physics and the theories surrounding time travel, there are a few proposed ideas and explanations that suggest changes to the timeline might not be possible.
The Novikov self-consistency principle: This principle, proposed by physicist Igor Dmitriyevich Novikov, suggests that the laws of physics prevent any event that would create a paradox. According to this principle, if time travel were possible, any actions taken by a time traveler would be already accounted for in the timeline, ensuring that no changes occur. Essentially, this principle suggests that time travel is self-consistent and that any attempt to change the past would be futile.
The "many-worlds" interpretation of quantum mechanics: According to this interpretation, every possible outcome of an event exists in a separate branch or parallel universe. If a time traveler were to alter the past, they would create a new branch or timeline, but the original timeline would remain unaffected. In this view, the time traveler's actions would not change their own timeline but would create a divergent reality.
Lack of observed changes: Another perspective is based on the absence of any evidence or observations of changes to our timeline. If time travel were possible and changes to the timeline were occurring, it would be expected that we would observe some anomalies or inconsistencies. However, so far, there is no empirical evidence to suggest that changes resulting from time travel have taken place.
It's important to note that these are theoretical ideas and speculative explanations, and they do not provide conclusive proof that time travel cannot lead to changes in our timeline. The nature of time and the possibilities of time travel remain active areas of scientific and philosophical exploration.