# Should history of physics questions be on topic?

When we last visited the issue of history questions, the dedicated History of Science and Mathematics Stack Exchange was in its early stages. At that time, we decided against closing questions for being historical, but with the implication that it may make sense to revisit that decision someday.

Now that HSM SE is well established, the time seems right to do that revisit. So, going forward from here, do we want history-of-physics questions to be on topic? Where exactly should we draw the line between on-topic and off-topic historical questions?

• For comparison, I started a related discussion on Mathematics Meta a few weeks ago. Jul 12 '16 at 21:59
• definitely HSM have to be promoted, it's existence isn't obvious and not well known, specially for some part of peoples who might to ask such types of questions. And history tag have to be edited to reflect that possibility and Emilio Pisanty view on that topic Jul 16 '16 at 3:19
• @MolbOrg Well, you can vote this ad up. But yeah, the tag wiki and excerpt could use some improvement. Jul 19 '16 at 11:01
• @EmilioPisanty interesting topic with ads. I believe that information have to be there where people need it(close as it reasonable possible), and tag is good place to be for it. Jul 19 '16 at 13:37
• @MolbOrg Sure. You're perfectly welcome to suggest edits to the current tag wiki. Jul 19 '16 at 13:41
• The key to developing new physics ideas (and understanding both current physics and historical physics (which has been replaced or superseded by new ideas)) is in understanding how the framework of physics has developed and been refined over hundreds of years. Therefore I would suggest that in many ways, the history of physics is not only on topic but more important than just learning current physics theory. Jul 27 '16 at 18:41

# Summary

History questions are welcome on this site whenever they have any bearing on our modern understanding of physics. However, if a question has only minimal or null bearing on our current understanding, or it specifically requires a historian's skills, toolset, and mindset to answer, then it should be migrated to the History of Science and Maths Stack Exchange site.

I think we should stay open to a significant set of history questions, and we should keep the tag. Unlike mathematics, the historical perspective is very often one of the key ways to understand the world and our knowledge about physics. The way physics is structured is very often centered around key experiments, and these are generally thought of as historical events and their contribution and motivation is understood in a historical perspective.

It doesn't have to be that way: you can perfectly well motivate, say, special relativity as one of only two possible cases, with the Galilean case ruled out through muon lifetime measurements, but you don't - you usually start with the Michelson-Morley experiment and tell the story from there.

(Math, on the other hand, does not have to do this: you can simply start with whatever axioms and definitions you want to work with, and you build your theory. Later on, or as an aside or a brief introduction, you might comment, as motivation, that the axioms went through this and then that version before people found the Right Version to use, but the brunt of the work in multiple fields $$-$$ particularly those taught in depth in physics degrees $$-$$ tends to follow from the axioms to the consequences rather than the historical refinements of the axioms.)

Going through recent, good-score questions on the history tag yields plenty of questions that are definitely of a historical character and yet have direct bearing on our understanding of physics, and which I think should definitely be on topic here. Taking a few non-rigorous picks,

On the other hand, there are questions that should be moved to the history site, because they require a historian's skills, toolset, and mindset to answer, and because they have minimal or null bearing on our modern understanding of physics. From the first page of the search above, for example, this could include

(For full clarity, these questions weren't migrated because it was too late to migrate them when this question was posted. If they were posted now, they would be migrated.)

However, I find that the set of questions that satisfy that criterion strictly is really rather small. There is, though, a relatively large gray area of questions that are primarily of historical interest, but that still illuminate aspects of how we think about physics and why we no longer think or do certain things. Some examples from this category are

I think these questions should be allowed here: they could also be asked at HSM if the OP is interested in a science historian's perspective, but there is no need to migrate them if asked here, in which case the focus should be (because it can be) on how that part of the historical record helps explain how we think of physics. If the OP wants to shift the focus specifically to what some historical character thought and did, what information they had available, and so on, then it can move to HSM.

• Comments are not for extended discussion; this conversation has been moved to chat.
– rob Mod
Oct 25 '18 at 13:19

In general, I'd say no, they should not be on topic here. However, I could see myself making an exception for questions asking how a problem in physics was historically solved. I don't mean a homework-like problem; I mean, for instance, how the Bohr model was realized to be incorrect and replaced with the more modern model. Questions asking about the history behind the development of strictly modern physics are probably okay. Questions asking about the history of the physicists themselves, the history of non-modern physics, or about historical practices in physics are probably off-topic. So, I would say that a question asking what the Ptolemaic model was replaced with would be off-topic because it doesn't directly involve modern physics.

• In your example with the Bohr model, I'd say that's not really a historical question. After all, the model is still incorrect today, and for the same reasons it was incorrect when it was first proposed. A question about how to realize the Bohr model is incorrect could be answered perfectly well in terms of modern quantum mechanics, without saying anything about history. Jul 13 '16 at 12:54
• @DavidZ Okay, that may have been a poor example. But how about the underlying point? Any thoughts?
– Jim
Jul 13 '16 at 13:02
• I dunno... it's a reasonable point, but I don't think I really agree with using modern physics as the criterion. I mean, it's not clear. History is cumulative; the history of any modern physics concept can be traced back at least to Newton. So I don't understand what marks the cutoff. Jul 13 '16 at 13:09
• @DavidZ Fair point. If HSM didn't exist, I'd personally welcome history questions. But it does exist, which means history of physics questions belong more there than here. Since I very much dislike cross-posting, I'd prefer all questions to be where they most belong, which means I have to side against the history questions being here. I wasn't sure where to draw the line either, so I picked modern physics as the most reasonable cutoff
– Jim
Jul 13 '16 at 13:12
• So, effectively, it's like we accept questions about history that happened after 1900-ish? I don't like the idea of using a date cutoff. I think we can find a more meaningful criterion. I do agree with putting questions on the site where they fit best. Jul 13 '16 at 13:20
• @DavidZ Yes, but it should be done on clear rules. Currently I have more than one historical questions what I simply won't ask, because the high - and unpredictable - probability of their closure makes the effort un-economic. On my opinion, if such a situation can appear, it is a problem. Jul 28 '16 at 22:52
• @DavidZ Another example, I would like to ask, if Galilei's - at the time available - experimental evidences had been enough to proof the heliocentric world view today. This question has obviously no chance here. And also not on the HSM, because estimating a the probable behavior of the today's science is not their topic. Jul 28 '16 at 22:59