What is our actual policy on science questions?

Question

One of the most contentious close reasons we have on the site is the one that designates real-world science questions as off-topic. The close reason is worded as follows:

"Questions seeking scientific solutions or explanations are off-topic unless they relate directly to a cited work of fiction."

Unfortunately, that last part seems to seriously muddy the waters: what does it mean for a science question to "directly relate" to a work of fiction? Just about every question asked on here cites some work of fiction. A question like "Could I make dilithium out of a lithium battery?" directly relates to Star Trek but I think it's exactly the kind of question we want to be off-topic.

On the other hand, most fictional works, even pure fantasy ones, operate with an implicit assumption that the laws of physics in the movie work just like the laws of physics in the real world, unless/until the work shows us differently. So many legitimate questions about the fictional universe will end up being answered using real-world science, because it's the same as the fictional science.

Different people, including different moderators, seem to fall at different points along the spectrum of possible interpretations, and it almost always leads to comment and chat "discussions" over which side a given question falls. So, can we try to pin down a community consensus over exactly where we draw the line?

For consideration, here are some previous meta questions that are related, but either don't quite answer this question, or else, there's no clear consensus in the answers:

• Are speculative science questions on-topic? (says that questions speculating about real-world science are off-topic)
• Are real world speculation questions still on topic? (a newer restatement/reiteration of the previous one)
• Are questions about current, or near-future science/technology on-topic? (says that questions about purely fictional science that has since become, or is likely to see become, real-science is on-topic; no clear consensus)

Also, here are some sample questions that are clearly asking about "real-world science" but with varying degrees of "related to a work of fiction". Note that I've tried to avoid questions from the very early days of the site, since their status may or may not reflect the current consensus (looking at you "Matrix Battery" question).

• "The Martian" and weight units [Closed]
• How could the matter converter in Tron Legacy generate an army [Open]
• How does mass conservation work in the MCU Ant-Man movie? [Open]
• How much power does the Martian heat ray output? [Closed]
• How can Quicksilver run with someone without injuring them? [Open]

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I think it would also be a good idea to lay out a policy for what good answers to these questions -- assuming they stay open -- ought to look like. That will at least give us something to point users to when trying to help them keep within the scope of the site, or explain why their otherwise-factually-correct answers might be getting downvoted.

Answer 1

In-Universe Explanations — Even Based On Real Science — Are On-Topic

Any question that is asking for an answer within the context of a fictional universe, even if that question requires real-world science information, is on-topic.

We should not expect content creators to spell out every detail of the science in their works. We can assume that works of science fiction and fantasy obey all the same natural laws that we are familiar with, until presented with evidence to the contrary in the work itself.

Answers should always be written from an in-universe perspective, and use only scientific information that is either explained, demonstrated, or at least not-contradicted by what can be seen within the work. Answers should also avoid trying to speculate how the science within a work might operate without evidence to support it. (e.g. there are humans breathing unaided, so we can speculate that the atmosphere of fictional Earth is similar to ours.)

Questions which are explicitly asking for an out-of-universe explanation of the science from a work of science fiction or fantasy should be off-topic.

For example:

• How much power does the Martian heat ray output? - Appears to be asking how a fictional device would operate in the real world.
• In terms of energy output, what type of bending is strongest? - Trying to apply real-world physics to something that explicitly has no scientific explanation in-universe.
• Is it possible for so many technologies to cease working? - Asking if something that clearly happened on-screen could "really happen".

(Note that, in many cases, merely asking the OP to clarify that they are looking for an in-universe explanation is sufficient to clean up a borderline post.)

Answer 2

I think Mike Edenfield's answer involving the in-universe/out-of-universe one is a good one, but I think there are some ambiguities in the definition and I also disagree with some of the examples given, so I'd like to suggest a slight modification of this idea:

Questions that require taking into account as much relevant canon in-universe information as possible, and then combining it with (or contrasting it to) real-world science to try to give an answer about how things work in-universe, are acceptable; questions that are more focused on how things might work in the real world rather than how we should understand them to work in-universe, particularly questions that require us to selectively ignore bits of canon information because they aren't scientifically plausible, are off-topic.

As an example of the latter, if someone asked "how might we build a Star Trek style faster-than-light warp drive in real life", but they wanted us to ignore all the things that have been said on the show about the warp drive relying on "subspace fields", since there is nothing that seems to resemble "subspace" in real-world physics, that would be too much of an out-of-universe question.*

On the other hand, Mike Edenfield gave the answer How much power does the Martian heat ray output? as an example of an out-of-universe question, but I think according to this standard it could actually be acceptable, provided we are asked to take into account all the scenes that might be relevant to judging its destructive power, and then combining that with "only scientific information that is either explained, demonstrated, or at least not-contradicted by what can be seen within the work" (one of Mike's criteria for acceptable questions). A similar example would be the question What is the wattage of the Death Star's superlaser?, which wasn't closed for being off-topic (though it was closed as a duplicate since the answer was already given incidentally in the answer to another question).

I also think it should be acceptable to just ask if a given description of some fictional technology or science could be understood in terms of real scientific ideas or engineering plans, as long as the full description is taken into account rather than being selective about what in-universe information to use. An example would be the question Accelerated decrepitude due to telomere length in Blade Runner, which asks us to consider the whole of a technical discussion about how to stop the accelerated aging of replicants, and asks if it could possibly jibe with real-world scientific ideas about aging being due to shortening telomere length. The focus in such questions should be about how the laws of nature work in-universe, whether certain real-world facts are being referred to by the characters (and thus demonstrating these facts hold in the fictional world as well) or if we have to assume they're talking about scientific findings specific to the fictional world. The focus should not be on asking whether the creators of the fictional world made a scientific error, or asking for detailed information on how things really work as beyond the information necessary to conclude they don't work that way in-universe. As Mike Edenfield suggested in the comments, a question of the type "Does X work in movie Y the same way X works in the real world?" is OK, likewise "Does X work in movie Y the same way X would be theorized to work in the real world, according to modern scientific theories" (for purely theoretical examples like Star Trek warp drive vs. the Alcubierre drive), but a question of the type "Is Thing X from Movie Y really possible?" is not. It can be a subtle distinction, but I would favor erring on the side of a "charitable" interpretation of ambiguous questions, or suggesting edits to make it a more clearly in-universe question.

*There should perhaps be some slight amount of wiggle room on the prohibition on "selectively discarding" in-universe information--the dependence of warp drive on subspace fields was established consistently over and over again in the Trek franchise, but in a question about a Trek technology, it might be acceptable to ignore a single odd statement about the technology made by a character in one episode of Voyager, for example. Likewise, when there seem to be internal inconsistencies in depictions of a given science or technology in the canon of a given fictional universe, it should be acceptable to just pick whichever side of the inconsistency seems to have more weight behind it, seems more favored by fans, or seems more scientifically plausible. Finally, there might be reasonable restrictions the questioner wants on what they want to consider "canon", for example someone might want to ask a question based only on how a technology was presented in the Star Wars films, ignoring books and TV series and other spinoffs.

Answer 3

Real-World Science With Any Relation To a Work Of Fiction Is On-Topic

Any question that relates back to a particular work of science fiction or fantasy, in any way, is on-topic. There is a lot of overlap between fans of science fiction and interest or expertise in real science. There's no reason we shouldn't allow questions that begin with a fictional premise and try to understand how such a premise might be possible.

Ideally answers should be based on as much information as we have about the work, but should feel free to draw on real-world science knowledge to fill in any gaps.

Answer 4

My viewpoint is that anything unrelated to a work of science fiction or fantasy is off-topic. We don't want people asking "How does a combustion engine work?". The answers are too mundane, and off-topic. Similarly, we don't want questions about fantastical technologies that are not bound to a specific science fiction or fantasy work, so we don't want questions of "How do I build a warp engine?" For one, there is no canonical answer outside of that universe. For two, it's too broad. What sort of warp engine? What laws of physics are we working within?

I would probably add to the first one that, if the question doesn't have a more interesting answer in said work of fiction than in real life, that's pretty off-topic too, but that gets into questions, sometimes, as to whether it's the case. Take, for instance, How did Rick make a silencer out of a flashlight?. It's got a perfectly mundane answer, but it does inform you of something in the show, that such a silencer can be built, and that the parts are likely available in-universe. At least in my opinion it's relevant. Since I answered it and all.

Answer 5

Real-World Science Is Always Off-Topic

Any question that requires answering using real-world science is off-topic. This site is for fans and enthusiasts of Science Fiction and Fantasy. We should not allow questions that require expertise in other areas, such as chemistry, physics, or biology. Those are out of scope for our site.

(See this answer for a longer explanation on this idea.)