I'm not going to talk about the plot, which was fine; I'm going to talk about how this movie was a typical Hollywood SF movie. But there may be spoilers in my discussion of what they did wrong.
See, I know that I've somehow become spoiled after a mere three examples of rockin' good SF from Hollywood: Interstellar, The Martian, and The Arrival. These three movies demonstrated beyond a shadow of a doubt that it is possible for Hollywood to produce real actual SF movies, not science fantasy stuff. (Not that science fantasy is bad; the original Star Wars, and Empire Strikes Back, were fantastic examples of the genre. Also Wrath of Khan and The Voyage Home, the only two really good Star Trek movies to date.)
I don't know why I expected Passengers to be hard SF. But it wasn't.
So let's look at the setting, first. The entire story takes place aboard Avalon, a starship bound for Homestead II, a colony world which is far enough from Earth that it takes 120 years to get there. The ship is designed to do everything automatically for nearly the entire trip, even to maintaining and repairing itself.
So far, so good.
We see the ship encountering some kind of asteroid field or something. At first I thought the ship was a Bussard Ramjet and wanted to say "Hooray!" but I rapidly learned that was not the case, and in fact the nebulous bit at the front was there to shield the lifesystem from meteoroids. Urk.
Problem one: at a certain point in the story, Laurence Fishburne's character says the ship is moving at 50% of the speed of light. Not unreasonable for a ship that's 30 years into a 120-year trip...but in that case, that shield at the front of the ship has to keep out radiation as well as micrometeoroids. And the meteoroid impacts? They wouldn't need to be the head-sized rocks we see; grains of sand would be more than enough to ruin anyone's day at that speed.
Oh: and a fiver says that you would be going a lot faster than 50% of C on a constant-boost ship that was boosting at 1 G for thirty years. Which leads me to my next point.
Problem two: the ship is rotating, leading me to assume that it's coasting...but at one point in the story the engine shuts off and there's a gravity fail. So, which is it? Centrifugal acceleration, or thrust? You don't need the big fancy rotating structure if it's a constant-boost ship. The lifesystem is a big spiral, which led me to wonder if that was made that way to offset Coriolis effects, but the story is opaque on where the gravity is coming from. Artificial gravity is another possibility, but it's just not explained at all well. If you have artificial gravity you don't need your ship to rotate (it may in fact be counterproductive) and you can build a ship that would be a lot more compact, which would in turn make your required radiation/meteoroid shield smaller in diameter.
Problem three: When asked why they don't just turn the ship around and go back to Earth, Fishburne says it would take them just as long to accomplish such a course reversal as it would to complete their trip, 90 years. Not sure about that one, either; if it's a constant-boost ship, she's been accelerating for 30 years, and it would take 30 years to stop. There's too much math involved to figure out how long the return trip would be, but I know it would be longer than 30 years but probably shorter than 60. But it doesn't matter: the trip would be long enough that they'd all be dead before they got back to Earth, anyway.
Problem four: One character is swimming when gravity fails. The water in the pool immediately begins to slosh out of the basin. She is caught in a big globe of water, disoriented because there is no longer a "down", but manages to swim to the outside of the globe.
...and as she exhales under water, the breath bubbles to the surface, the same side of the sphereule she's coming out of. NO NO NO! There's no gravity; the exhaled air would just hang there under water.
Of course, the water isn't finished sloshing, and she gets the "blue crush" effect when another blast of water comes out of the pool and hits the globule she's floating in.
Problem five: how much food will two people consume in the rest of their lives? Let's assume these two live to be 90 and they come out of hibernation at 25. That's 65 years each; for 65 years they must eat a certain number of calories every day.
The ship starts out with 5,000 passengers and something like 260 crew. They are to awaken four months out from their destination; the ship would therefore (it seems to me) have enough food aboard for 5,260 people for, say, eight months to be on the safe side. Is that enough food for two people to live on for 65 years? What effect does that have on the possible survival of the other 5,257 whose hibernation capsules did not open prematurely? I didn't bother to figure it out, but there was nothing mentioned in the movie to lampshade this issue, either.
Problem six: There has never, never, ever been a case where a hibernation capsule failed. It just never, never, ever happens. Not at all, not even once. The movie is quite explicit about this.
We are also shown that the crew's hibernation capsules are contained in an extremely secure place, an area of the ship that it is impossible to access without the right ID band. The main character tries to bypass the door control, he tries cutting it with a torch, he tries unnumbered other things to get access to the crew so he can wake someone up and get help with his predicament.
But hibernation capsules don't fail. Why is this level of security necessary? For damn sure you can't have a mutiny while the crew is asleep--hibernation capsules don't fail!--so the crew shouldn't need that level of protection prior to everyone waking up. And the crew is awakened first, before passengers.
Problem seven: They have an automated medical system--they borrowed Niven's term, "autodoc"--but there are things it can't do without a doctor present. Example: guy has stopped breathing, but autodoc won't attempt resuscitation unless there is a doctor there. That's great! What if there's no doctor available? "Sorry your husband died of that heart attack. We could have defibrillated him and saved his life, but there wasn't a doctor there to authorize the procedure." WTF is that about?
I can see the autodoc not being able to put someone back into hibernation--but then they discover it can do that, too! If there's a doctor present, or if you have a crew bracelet which lets you override.
So, yeah--no doctor needed; just a crew bracelet and the override code, and you can resuscitate people or put them into hibernation or--who knows?--get them a sex-change operation. Sheesh.
And, not to put too fine a point on it, what's the bleeding point of having an autodoc if you need a doctor to run the thing?
I enjoyed the movie about as much as I expected to. This was really an SF movie for girls, since the core of it was a love story; it's a little sad to think that if the story had just been given a little more of a hard SF core to wrap the love story around, I would have loved it.
The thing is, for this story, the only technologies I saw there that we do not have now? 1) continuous fusion; 2) robust artificial intelligence; 3) whatever that shield is that protects the ship from rocks and radiation. It otherwise could have been written using what we know right now.
So the ship could spin for gravity, or be designed for a combination of continuous thrust and spin gravity. It could have been a Bussard ramjet. (Would have to be, if it's fusion, because there were no fuel tanks on that bitch.) Say they launch it at Earth, somehow getting it up to 50% of lightspeed before it's too far away from the Sun. Ship coasts for 120 years, then brakes at its destination using on-board fuel. Time dialation and starfield compression would be barely noticeable at 50% of lightspeed; that stuff doesn't get extreme until you're well north of 80% of C. Not a problem to make this 100% scientific, and I would have appreciated the effort so much I'd be effusing about it.
Instead, they waved their hands a lot and did typical Hollywood science-fictional stuff. The result was typical, which is exactly what I expected. I wasn't disappointed, and I thought the movie was okay.
But just "okay".