According to the theory of relativity, as you approach the speed of light, time dilation occurs, which means that time appears to pass more slowly for objects in motion relative to those at rest. This phenomenon has been experimentally observed and verified.
If you were to travel at speeds close to the speed of light relative to an observer on Earth, time would indeed appear to pass more slowly for you compared to someone who remains on Earth. This effect is known as "time dilation." As a result, you would age more slowly from the perspective of the Earth-based observer.
However, it's important to note that this effect only applies to the traveler in motion and not to the subjective experience of the traveler themselves. From the perspective of the person traveling at high speeds, their own sense of time would remain unchanged.
In terms of practical applications for making aging slower, it's not feasible with our current understanding of physics. Achieving speeds close to the speed of light would require a tremendous amount of energy and would come with significant challenges and limitations. Additionally, the effects of prolonged exposure to such speeds on the human body are not well understood and could have detrimental health effects.
While time dilation is a fascinating aspect of relativity, it is not a practical solution for slowing down the aging process. The study of aging and attempts to extend human lifespan involve other avenues of research, such as genetics, cellular biology, and medical advancements.