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here was my original question

It got downvoted quite a few times from not being specific. I edited it so it can be better understood. Then it was closed for being off topic. I don’t understand why asking about effects of gravitational waves under the gravitational waves tag is off topic.

I think I deserve an explanation for the question being forcibly closed.

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  • $\begingroup$ I don't see why it was considered off-topic. I think it could be improved, but the main question is if GWs can make matter emit electromagnetic radiation, which is certainly a question on mainstream physics $\endgroup$
    – Níckolas Alves
    Commented Aug 1 at 7:33
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    $\begingroup$ @NíckolasAlves it may not be off-topic but what does "So 4vector position in general relativity is dotted with the metric, which when in the correct gauge and when taken multipole expansion of emits a wave equation" mean? $\endgroup$
    – ZeroTheHero
    Commented Aug 1 at 14:30
  • $\begingroup$ You are new to the stack exchange, so I'll let you know that we all go through this frustration at having questions closed for reasons we don't understand. Especially if you are asking about unusual things. It happens A LOT. Don't take it as personal. And don't bother re-writing a question in the same box because it probably won't make a difference. Make changes and ask in a separate question. $\endgroup$
    – foolishmuse
    Commented Aug 1 at 15:49
  • $\begingroup$ @ZeroTheHero I don't think it is well-written. It certainly needs clarity, but I disagree that it is off-topic $\endgroup$
    – Níckolas Alves
    Commented Aug 1 at 21:25
  • $\begingroup$ @NíckolasAlves yes I suppose we’re all guilty of the occasional bout of laziness and VtC a question for the wrong reason, even if it deserves to be closed. $\endgroup$
    – ZeroTheHero
    Commented Aug 2 at 18:00

2 Answers 2

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As it is currently stated, question does not make any sense, partly due to wrong English, partly due to incorrect statement semantics, partly due to content mixing and absence of post main topic. And also partly due to invalid Physics, such as

Then there’s quantum mechanics with Heisenberg uncertainty [x,p] not zero, so when x vary p varies.

At first, what you have wrote here is not Heisenberg uncertainty principle, but commutator of position and momentum operators, which should be expressed as : $$ [{\hat {x}},{\hat {p}}]= {\hat {x}}{\hat {p}} - {\hat {p}}{\hat {x}} = i\hbar $$

Second. Uncertainty principle $\Delta{p}\Delta{x} \ge \dfrac{h}{4\pi}$ does not state that in case of coordinate variation, momentum must vary. Actually it's quite contrary,- when particle position is well-localized (coordinate is fixed, i.e. does not vary), then particle momentum varies by unimaginably large quantity of statistical error. And when particle coordinate varies a lot,- then particle momentum approaches constant, i.e. is stable.

Overall,- your post is by all means unreadable. That may be the root cause of your post closure.

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  • $\begingroup$ The uncertainty principle is derived from the commutation relationships, so I thought specifically that would suffice. Δx Δp are essentially the standard deviation or spread of observable in concern. Which would vary with geodesic deviations, considering parts of spacetime gets closer together and parts grows apart. Geodesic deviations must happen when the metric itself admits a wave like nature. $\endgroup$
    – robin wang
    Commented Aug 2 at 0:11
  • $\begingroup$ I have since clarified my original question, hopefully it is more readable now. $\endgroup$
    – robin wang
    Commented Aug 2 at 0:35
  • $\begingroup$ Yes, it is related to commutator of operators, but even then you have not mentioned a full relationship, which is $$ \sigma_x \sigma_p \geq \langle \frac {[{\hat {x}},{\hat {p}}]}{2i} \rangle .$$ Mentioning just part of equation does not make much sense. Also it has been accepted to use $\sigma$ notation for defining standard deviations, such as $\sigma_x$,- for $x$ coordinate standard deviation, instead if $\Delta x$ which is used in context where ones needs to define absolute coordinate error. $\endgroup$
    – Agnius Vasiliauskas
    Commented Aug 2 at 6:17
  • $\begingroup$ I was thinking something like this: physics.stackexchange.com/questions/349850/… $\endgroup$
    – robin wang
    Commented Aug 2 at 17:46
  • $\begingroup$ It should be completely specifiable with just communication. Yes the Δx is not just used for the uncertainty principle case, but it could be. It could also be used for approximations of derivatives, and for things like a small perturbation. Same notation is used for a laplacian. Sam notation is used for a change in x. $\endgroup$
    – robin wang
    Commented Aug 2 at 17:49
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Voters of this site tend to get itchy for GR-related questions. Only they know, why. Also I had already trouble with their this behavior.

I suspect, they might interpret it as the covered propagation of non-mainstream or own-invented layman ideas. Thus, they vote to close, down, delete without too much thinking. But honestly, I am not sure.

However, the rules are clear, and actively pursuing the topic on the meta helps. What I a see a much more large problem, that most of the unfairly closed GR-related questions never gets to here, it remains only closed, downvoted and deleted content, and its OP silently leaves the site.

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  • $\begingroup$ In this case it doesn't look like the topic is the real issue $\endgroup$
    – BioPhysicist
    Commented Aug 19 at 3:58

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