Based on our current understanding of physics, it is generally considered more likely that faster-than-light travel would be impossible, while the possibility of time travel remains uncertain and speculative.
According to the theory of relativity, as formulated by Albert Einstein, the speed of light in a vacuum represents an upper limit on the speed at which information or matter can travel. This limit, known as the speed of light barrier, suggests that surpassing the speed of light is not achievable within the framework of our current understanding of physics.
On the other hand, time travel is a concept that has been explored in various scientific and theoretical frameworks, such as general relativity and certain interpretations of quantum mechanics. While time travel to the past is often associated with paradoxes and logical inconsistencies, some theoretical models, like wormholes or certain space-time geometries, have been proposed as potential mechanisms for enabling time travel. However, these concepts are highly speculative and remain purely theoretical at this stage.
It's important to note that our understanding of physics is constantly evolving, and new discoveries and theories may emerge in the future that could challenge or expand our understanding of these concepts. But as of now, based on our current knowledge, faster-than-light travel is considered less likely than the possibility of time travel, albeit both are still largely speculative.