Yes, time dilation works in reverse as well. According to the theory of special relativity, if an observer is moving slower relative to another observer, they would experience time passing faster compared to the stationary observer.
To understand this, consider two observers: one who is at rest on Earth and another who is moving at a high velocity relative to Earth. From the perspective of the stationary observer on Earth, time for the moving observer will appear to be passing slower.
This phenomenon can be illustrated with the "twin paradox." Imagine two identical twins, where one stays on Earth while the other travels on a high-speed space journey. When the traveling twin returns to Earth after their journey, they will find that less time has passed for them compared to their twin who remained on Earth. This is because the traveling twin experienced time dilation, and as a result, they have aged less.
It is important to note that both observers are in inertial frames of reference, meaning they are moving in straight lines at constant velocities. If the observers undergo acceleration or change their velocities during their motion, more complex considerations come into play.
So, in summary, time dilation is a symmetric phenomenon in special relativity. Observers moving slower relative to other observers will experience time passing faster, while observers moving faster will experience time passing slower compared to a stationary reference frame.