The Epstein drive is key to making the story actually work though, without it all the travel times would be elongated and the whole thing would fall apart. Honestly I think they did an amazing job of keeping the fictional science to a minimum, including the Epstein drive (although protomolecule stuff is basically magic).
For sure, really helps smooth things over when travel times between conflicts arent like 13 months or years.
It is worth noting though that a show like GoT was at its best when fast travel didnt exist, we'd all just like to forget about those unspeakable later seasons
It's a lot less fiction than many other fictional spaceships. It's not an FTL drive or anything, it's just an ordinary rocket engine with an extremely high Thrust-Weight ratio
And that thrust to weight and high specific impulse is because it's using fusion pellet design. Coincidentally the same strategy which recently got energy gain from the national laboratory.
I have a running theory that the best grounded sci fi get one big free technology that doesn’t need to be based in anything realistic whose implications create the rest of the setting.
In Mass Effect, it’s the mass effect created by eezo that allows for gravity manipulation. It’s how cars can fly, ships can travel between planets, and biotics get their superpowers. It allows the universe to ask “how would the world be impacted by gravity manipulation?”
In The Expanse, at least leading up to the events of the first book, it’s the Epstein Drive. How would continuous thrust allowing for interplanetary travel over days/weeks instead of months/years affect society’s growth? It allows for a more rich and interesting world by only asking for one strong suspension of disbelief.
What makes you say the Epstein drive is pure fiction? If we can figure out fusion, it's probably not that far off. Constant acceleration is a powerful force.
Even if we do figure it out there may be significant barriers to implementing it in such a way that The Expanse displays its use.
For example, the Harry Potter invisibility cloak. We've figured out how to cloak things from sight in very controlled parameters but to apply it in literal cloak form like in the movies? Fiction
I mean, I feel a little like that's saying, "Flying machines?! Fiction." in the 1800s. I'm pretty optimistic that we'll succeed with fusion, given the current state of the technology
You do realize what’s considered fiction can change as time goes on, right? What we call “fiction” is just a thing that doesn’t exist, but it doesn’t mean it can’t or won’t exist later.
TL;DR you can both be right. Now take your cookies and relax.