According to the theory of special relativity, as an object with mass approaches the speed of light, its energy and momentum increase significantly, and its mass appears to increase as well. This phenomenon is often referred to as time dilation. As an object approaches the speed of light, time appears to pass more slowly for that object compared to a stationary observer.
If a hypothetical human were to somehow travel at nearly the speed of light, such as riding a photon, time dilation would indeed occur. From the perspective of the human on the photon, time would pass much more slowly compared to an observer at rest. This means that, in theory, the human could travel vast distances across the universe while only perceiving a relatively short duration of time.
However, it's important to note that while time dilation allows for the perception of less time passing, it does not suspend biological processes or eliminate the effects of aging. To an outside observer, a significant amount of time would still pass. For example, if the human traveled millions of light-years at near-light speed, they would experience only a short time, but millions of years would have passed for observers on Earth.
Additionally, there are numerous practical challenges and physical limitations associated with achieving such speeds. The amount of energy required to accelerate an object with mass to near-light speed is enormous and currently beyond our technological capabilities. The effects of radiation and other hazards in space would also pose significant risks to the human traveler.
Therefore, while the concept of time dilation allows for the perception of shorter travel times, the practicality and feasibility of achieving such speeds and surviving the journey remain speculative and well beyond our current scientific capabilities.