If time travel were possible, it raises the possibility of altering events in the past, which could potentially result in changes to the future. In theory, someone who travels to the past could take an object from the present and introduce it into the past timeline, thereby altering the course of events and potentially creating a situation where you never had that object before.
This concept is often referred to as the "grandfather paradox" or a causal loop. It raises logical and philosophical questions about the implications of changing the past and the resulting effects on the future. However, it's important to note that the exact consequences and mechanisms of time travel, if it were possible, are still purely speculative and not yet scientifically understood or confirmed.
It's also worth mentioning that there are various theories and models proposed in physics to reconcile the possibility of time travel, such as the Novikov self-consistency principle, which suggests that any actions taken by time travelers would be inherently consistent with the timeline they are in, ensuring that no paradoxes occur. Other theories propose multiple timelines or parallel universes to avoid inconsistencies.
It's important to remember that we currently lack empirical evidence or a complete understanding of time travel, so its implications remain purely speculative and open to interpretation.