According to the theory of special relativity, as an object approaches the speed of light, time dilation occurs. Time dilation means that time appears to pass more slowly for the object in motion relative to an observer at rest.
However, according to the same theory, it is impossible for an object with mass to reach or exceed the speed of light. As an object with mass approaches the speed of light, its energy requirements increase to infinity, making it physically impossible to achieve that velocity.
That being said, let's consider a hypothetical scenario where an object could travel at the speed of light. In this case, time dilation would be significant. From the perspective of the object traveling at the speed of light, time would appear to stand still.
However, from the perspective of an observer on Earth, time would continue to pass as normal. This means that, while the object is traveling at the speed of light, no time would pass for the object itself, but time would continue to progress on Earth. The duration of the journey from the object's perspective would be instantaneous, but from the perspective of observers on Earth, time would continue to elapse normally.
It's important to note that this hypothetical scenario of an object traveling at the speed of light violates the principles of our current understanding of physics, specifically the theory of special relativity.