You have likely heard the term "space-time" since it's taught by scientists and teachers, except time isn't a physical phenomenon. Understand we have lots more to learn in science to understand more of the universe. There is only the NOW, the past are memories, the future is possibilities. Knowing the space co-ordinates and time is useful for spaceflight, but for warp travel space density is warped, not space time. Atomic clocks do not prove time, our technology acts different in different gravity conditions. We can't measure time like how temperature is measured. The official definition of the second was defined in 1967 "The second is the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom." Before time was invented humans measured existence from each sunrise was a new day, we split a day into 24 hours with 60 minutes per hour and 60 seconds in a minute. There is no actual science to prove time, atomic clocks prove our technology will give different results in different gravity conditions, gravity can impact how our technology records time, this doesn't prove time is something real.
Try and imagine the space density like a bubble, gravity can warp such density its the "fabric" of the universe that's how we can see gravitational lensing the galaxies we see from the lensing are all warped.
If you take off with a spacecraft traveling at warp two times the speed of light and you and a friend on earth start recording the seconds that pass, by the time the spacecraft comes back to earth the "time" will have passed faster on the spacecraft but both people would still be the same age, one clock was in different gravity/cosmic conditions impacting the recording of time. If both people were 30 and the mission was 60 years both people would still be 90 years old, just because one clock started running faster doesn't mean anything other than our technology works different in different conditions. We invented time, we created technology to keep track of time that passes to better coordinate life. For temperature mercury expands contracts hence we can measure temperature, we don't measure time like temperature not even close, air speed we can detect, pressure we can detect, atomic clocks are human technology, not a natural thing measuring a physical phenomenon. One day science will prove either way but whatever mainstream science is doing can't explain dark matter and dark energy, we have much to explain in the universe how it works, we can't assume our current understandings are good especially when there isn't any science that uses a device that is not impacted by gravity, or any other cosmic phenomenon, such technology doesn't exist yet. To record a perfect second 100% and never go off is something we simply can't do right now, just because our man made technology changes how we record a second in space doesn't prove time, we need more science there isn't enough to say time is a physical phenomenon. We are at an early stage of understanding a lot about the universe, we know a lot but there is much more progress to be made, as we learn more about dark matter and dark energy new mysteries will likely come as a result.
Time travel would violate the laws of thermodynamics, you can't create energy out of nothing. Do people realize just how much energy would be required for the universe to remember every last detail in super cosmic resolution every blade of grass on every planet, every atom, every cloud, every piece of sand on every planet, yikes that's a lot of energy required to remember every nanosecond, what did people think time would be on the hour or something? if we can measure it, the universe would have to remember.
Consider I grew up going to school not learning that hemp seeds had more protein by weight than meat or fish, and hemp is one of the few food sources on the planet that have a near perfect balance of omega fatty acids. How come schools didn't teach science? I grew up being unhealthy and when I learned on my own I didn't need meat or dairy I went vegan over a decade ago. I want to live a long, healthy life, not be another stat dying from a preventable disease caused by meat eating. Not everything that is accepted by mainstream is 100% we have a lot more to learn, scientists are wasting time on a theory about time that isn't giving us results in figuring out mysteries in modern science. Atomic clocks may help us better understand more about the sun but we aren't detecting any physical phenomenon with natural methods.