Reading the books for the first time. How unreasonable is my gripe about thrust "gravity"?
With the show being one of my favorites, I'm happy to say that I'm really enjoying the novels as well. That said, it keeps bugging me when the term "thrust gravity" is always used to describe something that's explicitly Newton's 3rd law - ie, not gravity. I'm probably not understanding something, but it bugs me to see a series that makes a point to be at least reasonably scientific to use a term that seems so wrong.
Side note: How come the third law missed out on natural feeling shorthand? 1st - inertia. 2nd - f=ma. 3rd - ???. Feels like something got overlooked there.
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It feels like a natural term that might arise. It's not literally gravity but it feels like gravity so people call it gravity. In the same way we casually say "zero gravity" for situations where there is gravity but you can't feel it.
It'd make more sense of it was just in-universe jargon used in dialogue, but it's also used in narration, which doesn't feel like it fits with the rest of the scientific focus, at least not to me.
For accelerating reference frames, you need to move past newtons laws and use general relativity. In that framework, an experimenter enclosed in a box cannot distinguish between acceleration and gravity except in detecting very minute lack of parralelism due to the radial direction of gravity.
https://www.einstein-online.info/en/spotlight/equivalence_principle/
I personally would not get hung up on that term.
Sure, it feels similar, but it still doesn't seem appropriate to conflate the two. If someone said airplanes use "anti gravity" to fly, that'd blatantly incorrect, no? It doesn't help that the series focuses on actual gravity and it's consequences constantly, which just shines a spotlight in this particular incongruence (for me, at least).
Not just feels similar; any experiment conducted would yield identical results assuming the source of thrust is perfectly constant without variations.
But rather than continuing to discuss the ways in which you dislike "thrust gravity," is there a term you would find preferable instead?
Moderately misleading terms is pretty common in real science and technology though. For example, particle spin has nothing to do with actual rotation and instead just has properties that is similar to objects with rotation. So getting obsessively hung up on semantics would be a very frustrating activity even in actual scientific literature.
This is the second time you've suggested I'm mentally unwell for having a minor gripe. The rest of your comment is on topic, but I'm not continuing to engage in that sort of discussion. If you don't want to have a conversation about the topic at hand, feel free to stop commenting. If you do, stop being so insulting.
Does it bug you when someone says "almond milk"?
Because it's literally the same thing.
"Almonds imitating milk" and "thrust operating gravity".
I have a bad habit of back rationalizing science fiction, but if they just say "thrust gravity" conversationally, then it is 100% realistic even outside of science to be a shorthand and not literal. I never did read the books, so I might be wrong.
One's a marketing title while another is meant to be scientific. Those aren't really comparable.
If it was just used in dialogue, I don't think I'd mind as much, but the narration uses it like it's scientific nomenclature. Maybe it is the best term for the effect, but it leaves me unsatisfied.
Is it meant to be scientific? Or is it meant to quickly communicate a concept in a sci-fi?
Why can't it be both?
Depends what the author cares about, I guess?
It is probably just to make it simple to understand without being awkward. To always have to say that it is thrust causing acceleration that mimics the force of gravity is way too long. It gets the idea across succinctly, and it is a novel not a scientific paper.
Where did I say it should be long and awkward? Words are invented all the time to convey more complicated concepts. It doesn't seem unreasonable to suggest that could have been done here.
So you'd prefer they invent a word instead of using existing words that are easily understood by the reader? How would that improve anything? It wouldn't be any more scientifically accurate, and would be harder to understand.
Sure. My only issue is that it's scientifically inaccurate, so I don't see a problem with that. Writers invent words all the time and I don't really consider it confusing as long as they're adequately explained at some point.
So the author invented calling it thrust gravity. How is that different than explaining it and saying it is something like t-grav? They are both made up names for the same thing. And there is a scientifically accurate description of what is happening in the book. So I still am failing to see how using a different name is more or less accurate.
I already explained why it's different. I'd also have an issue with people calling lift on an airplane "anti-gravity".
Buddy...
If you don't think science chops phrases up as much as the military invents acronyms...
You're going to be very confused with realistic sci-fi
Right, but it explains lots of things as if the reader is familiar, right?
When they say "ship" do you picture a boat instead of a "spaceship"?
It's all the same thing. This is like if you argued that "get to the ship" is bad writing because in your head your picturing something different. That's fine, everyone does that.
But you're insisting your interpretation is right, and refusing any of interpretation that solves your issues with your own.
Ah, that's my problem - I don't understand how basic shorthand or creative writing works because I've apparently never read anything else in my life. Clearly you're right and I'm wrong in this discussion about something else entirely. Congratulations, you win.
I suddenly understand why you don't understand basic concepts...
Everyone in this thread is trying to explain the same thing to you in different ways, and you're treating each one as the other person being the problem and refusing to step back and ask yourself if it's even possible you're wrong and everyone else is right.
Everyone in this thread "wins" if you understand this, but that's clearly not going to work.
So I'll block you, and never accidentally put time into helping you again.
'gravity-like acceleration due to thrust' 'thrust gravity'
Works for me, especially when you actually have a need to distinguish the source of the acceleration
Sure, and that's definitely helpful, but I'd be more satisfied by "thrust [other word]".
What other word would you use for a gravity like effect, that works to describe how it affect the people on the ship?
The ship experiences accele forward, and the occupants inside experience that as a gravity like effect.
Right - Newton's 3rd law. As I mentioned in my side note, I don't know if a singular word exists for that. "Action-reaction" is a term I've seen, but that's pretty clunky. Afaik, a new word would have to be coined to express that interaction. If I had to suggest something, my off-the-cuff, "probably wrong in even more ways" idea would be "pronertia".
not a bad word, problem is i hear that, and for some reason i think potential energy, not a gravity like effect! How about gravnertia? Inertia which causes a gravity like effect
Yeah, but the whole point is that the effect felt is the 3rd law in action - one thing pushes against another thing, and that thing pushes back. While gravity can cause that, it's not gravity itself, right? If I catch a ball that's in motion, it's the force I apply to it that stops it, not gravity. Same thing for ships in thrust, or spinning stations. It's all 3rd law in action, not just different versions of gravity.
Yea, but language is about communication, not absolutely precision.
This isn't a scientific paper, this characters and naritive trying to express ideas, and there clarity of intent and idea is more important than scientific rigour.
The term I'm aiming for is for the concept of Newton's 3rd law, not the book.
The series talks about three different types of "gravity", being down the well, which is being on a planet and experiencing mass attracting mass, spin gravity, which is created using the Coriolis effect of being stuck to the inside surface of a spinning project, and thrust gravity, being under acceleration of a ship.
For all practice purposes, thrust and well gravity are identical, aside from hearing the engines, you would not be able to tell the difference between 1g on earth and a ship under 1g of acceleration in a straight line. The whole point of the Epstein drive in the show is "We have such a powerful engine we can just keep accelerating", get places very fast, and live with a defined up and down.
Spin gravity is distinctly different as the rotation is detectable, and depending on the radius of the ship / station / rock, can cause a dizzying effect. Belters like to distinguish themselves because the are generally immune to effects of spin gravity.
All of these effects are quite real, and in my opinion the series does a great job of being scientifically accurate.
It's likely for the reader's sake more than anything. A person in The Expanse can experience two types of pulling downward. Actual gravity on a planet/moon, or during a burn. I would agree that they probably wouldn't say "thrust gravity" usually because of context (they know they're on a ship), but technically "gravity" alone would be incorrect, even though in its use it's realized it's referring to the force from the thrust and not a gravity field. A new word might even be created to talk about ship "gravity".
Most likely, though that does feel pretty patronizing if true. A new word would've felt better, imo. Or even something like "thrust g's", reminiscent of modern jet planes of today.
You know what the "g" stands for right? XD
Gravity is the effect. You can use thrust, spin, or a gravity well to create it.
You are wrong to assume gravity can only mean one of those.
Force is the effect, gravity is the cause. Gravity, thrust, and spin accelerate us or other objects and it's our interaction other objects that we feel. So "thrust gravity" is taking two concepts that work similarly and mashing them together. Like, if someone called an electric stove "electric gas", that is just the two things used to create heat, but nothing about the heat itself. It's a misuse of the terms.