[cfadvan]

To be totally fair, FTL implies time travel, and even sub-light (but hefty fractions of light) lead to staggering time dilation effects. None of this is ever touched in most sci-fi and certainly not Star Trek. Everyone is sipping around at high multiples of lightspeed, yet no one ever remarks that they constantly arrive before they leave. They use impulse drives to go at high fractions of c, yet they never return to an Earth many thousands of years in their subjective future.

It’s a great series, but it’s not hard sci-fi, just a great storytelling mechanic.

[krapp]

True, but no one ever claimed (or should claim) that Star Trek was "hard" sci-fi.

At best, it sometimes tried, depending on the writer, to make nods to actual science. The original series seemed to have input from actual engineers and scientists, which is why you have the nacelles separated (to protect from radiation) and Bussard collectors, but then as time went on, it sort of became magic particles and subspace and not even bothering with the pretense.