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Thread: What would happen to space-time if something huge suddenly accelerated/disappeared?

  1. #61
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    Quote Originally Posted by EDG View Post
    And the poster's history shouldn't make a difference to any answer given - why should it? Or are you just assuming from the start that the poster is going to try and turn it around in an ATM way? That seems extremely paranoid.
    (bold added)

    Because that history tells you a great deal about how much the poster already knows, or understands, about the background to the question.

    Because in trying to answer a question, one should always address it first to the audience that is the person asking the question (or do you disagree?)

    If the OP uses the term "space-time", and from that person's previous posts you can see they understand - at some level - that space-time is a concept derived from GR, then surely you need to tailor your answer to incorporate that aspect of their understanding, don't you?

  2. #62
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    Quote Originally Posted by EDG View Post
    Quote Originally Posted by Nereid
    If so, then the answer "the question is meaningless, because mass doesn't just appear or disappear like that; would you care to try to ask a more meaningful one?" would be entirely appropriate, wouldn't it?
    *facepalm*. You really aren't listening to a word I'm saying are you.
    Au contraire, mon ami, au contraire.

    In fact, I'm trying - very hard - to understand what you are saying (and, it seems, failing spectacularly).

    Or, as Jens said, "I think the problem with questions like that is that it would violate the conservation of matter, so you are asking a hypothetical question about something that cannot happen in the first place."
    Perhaps you missed the part where Jens said "In any case, initially I wanted to say that there was a problem with the idea since the assumption is physically impossible, but that doesn't mean I was saying there should be any reason not to talk about it.".

    The question is as stated by the OP. The way I see it, generally socially acceptable responses are to either attempt to answer it, or to ignore it and answer questions more to your liking. Throwing a strop about how it's not a "meaningful" question just makes you look obstructive, unhelpful, and intellectually snobbish.
    Now it's my turn ...

    *facepalm*. You really aren't listening to a word I'm saying are you.

    Please read my last post.

    Note: the second question in the OP includes a massive inconsistency ("space-time" and "disappear").

    But surely, if so, a far, far more interesting question would be something like "are perpetual motion machines possible if mass can disappear?" or "how different would the universe be if mass-energy were not conserved?"
    So you're saying that don't approve of the OP's question, and would rather answer something else. Well, if those questions actually get asked, I'm sure you'll have a ball with answering them. But that's not what the OP asked here.
    No, I'm saying that if you accept that the OP "realises that mass doesn't just appear or disappear like that" (your words), then pointing out an obvious consequence is nigh on mandatory, if we are to conform to BAUT's policy on Q&A.

    Perhaps I have not made this criterion sufficiently clear, yet.

    That gets to the heart of the question.
    The one that most other people saw straight away without the pedantic arguing?
    Again, here we may have to agree to disagree.

    What you see as "pedantic arguing", I see as conforming to the BAUT rules on Q&A, and the spirit of this whole board.

    What do you think science is, beyond a formalised system of pedantic arguments?

    Perhaps, then, the best possible answer one could give (within the bounds of BAUT's Q&A) would be something like "It depends, critically, on how the Sun suddenly completely disappeared", which you could expand into a discussion of GR, the nature of physics, etc.
    Which again, doesn't actually answer the OP's question.

    However, to fail to point out that the (original) question is essentially meaningless would be a gross failure indeed.
    The fact that it's meaningless to you has no bearing on whether it's worth answering or not.
    Here, I think, you are sanctioning non-science, albeit indirectly.

    Whether the specific question we are discussing (about space-time and planets disappearing) is meaningless, scientifically, or not can be established objectively, and in a way that is independently verifiable.

    In fact, it adds a critical element that makes the question potentially answerable, beyond the way Jens first answered it.
    The question is eminently answerable as it stands. I'm sorry that you're not capable of understanding that.
    I look forward to your response to my last post, where I made an attempt to answer the question, as asked.

    Suspending disbelief is great, and is done all the time in science.
    By other people, it seems.

    However, when the belief that is suspended is equivalent to "let's say one of the two best theories we have in physics is grotesquely wrong in a way that is not specified", then we would be remiss in not pointing that out, wouldn't we?
    You've pointed it out ad nauseam, and made no attempt to answer the question asked. Like I said, this isn't ATM, it's a what-if question. Nobody's even said anything about any theories being "grotesquely wrong" either.
    I think you're wrong on that, and it may be possible to show that you're wrong, objectively.

    Seriously, if we can't even entertain hypothetical what-if questions on this board, then what's the point of this place?
    Of course we can entertain such questions!

    But in answering them we are bound by BAUT's Q&A policy - wild speculation, of a non-science kind, is verboten.

    Do we have to submit questions to self-appointed thought-police to get them vetted for scientific validity before anyone is allowed to answer them? That's a great way to encourage curiosity, I'm sure. I'm seeing more and more of this attitude on BAUT, and it makes me wonder if it's even worth hanging around here or pointing people to this place. It's just getting downright hostile and unpleasant.
    I'm sorry you are getting this impression.

    What I don't - yet - understand is why you think "that question cannot be answered in a scientifically meaningful way, and here's why" (or similar) is an unacceptable response to a question like the OP's second one (which, may I remind you, begins with the words "space-time").

  3. #63
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    Quote Originally Posted by EDG View Post
    Quote Originally Posted by Nereid
    If I may, I'll ask you the same question as I just asked novaderrik:
    I already answered it in a civilised manner in my first post on this thread. And the poster's history shouldn't make a difference to any answer given - why should it? Or are you just assuming from the start that the poster is going to try and turn it around in an ATM way? That seems extremely paranoid.
    (bold added)

    If I am not mistaken, that post is this:
    Honestly, do folks not recognise a thought experiment when they see one? It doesn't matter if something being asked about can or can't really happen, the point of framing the question is to try to figure out what would happen if it was possible. It involves things like extrapolation from known facts/theories, educated guesswork, and imagination, which are all very useful for figuring out science.

    I recall reading a book about Gravity Waves years ago from the university library (I forget the name of the book unfortunately. I think it was "Understanding Gravity Waves"?) and remember it saying that if the sun was to suddenly vanish then the consequences would propagate out at the speed of light. So we'd carry on orbiting around the Sun as if it was there for about 8 minutes (the speed of light delay between Earth and Sun) after it disappeared, and then the earth would fly off at a tangent from our orbit since we'd "know" that the central mass wasn't there anymore.
    I'm sorry, but I don't see how that answers the question I asked novaderrik.

    Here is that question again (bold added): In the particular case of the second of the OP's questions ("Would space-time get disturbed like the wake and bow wave from a boat [...] or oscillate like the air around an implosion if said planet/star was made to disappear?"), what do you think a non-intimidating, but scientifically sound, response would look like (in general, not that the specifics need to be exactly right)?

    Specifically, I can't see how you've addressed the OP's (second) question at all!

    Pedantically, the OP asked about "space-time get disturbed like the wake and bow wave from a boat", and "oscillate like the air around an implosion"; what I think you are saying is your answer doesn't address either of these points, does it?

  4. #64
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    I do enjoy this type of question... even if I feel the need to scream, ' But it Can't ' That fact is well established and said.
    And is not helping answer the question... " What happens to space time if something huge suddenly accelerated/disappeared ?"
    So I will answer it as I see it. Which may not be technically correct. Firstly I see two questions not one.
    If it were 'accelerated' and 'disappeared' that would be easy... it just suggests the light image can not reach us from a red shifted at c. object.
    but it does not say that does it ? That little / changes the meaning for me. My befuddled mind sees it as a 'or'... am I right ?
    If that is what is intended then, Its a black hole. It still has all the mass and forces that it should. ,but has vanished as its light path is unable to reach us. Its still there.

  5. #65
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    Quote Originally Posted by Nereid View Post
    Pedantically, the OP asked about "space-time get disturbed like the wake and bow wave from a boat", and "oscillate like the air around an implosion"; what I think you are saying is your answer doesn't address either of these points, does it?
    I think you're obsessing about that question so much that you're missing the general point. I don't think he meant "is it either this option or that option (and nothing else)". I think he's just throwing out the first two ideas he thought of for how it could respond, but there could be other ways too that he's not thought of.

    He just wants to know how it would respond if the mass went somewhere non-local instantaneously. Yeah, big deal, it can't really do that - we get it already. But if it did blip out, disappear, teleport, whatever - then what would happen? How could space-time respond to such a change?

    If we don't know, or can't tell, then just say so without the patronising attitude. If we can hazard a guess based on what we know, then do that instead (which is what I did in my first post). Being deliberately obtuse about it isn't helping anyone though.

  6. #66
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    Quote Originally Posted by north View Post
    because time , is based on the speed of light , and space is space , until you get a mass involved , then you have a mass IN space

    then that light can be bent because of the mass in space

    for example , star-light from behind the sun is bent towards us , Earth , and we can see this star even-though otherwise we could not see this star
    gibberish

    Light folllows a geodesic in spacetime.

    This is in now way an explanation of "why space and time become spacetime", whatever that is supposed to mean.

  7. #67
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    Quote Originally Posted by EDG View Post
    I think you're obsessing about that question so much that you're missing the general point.
    The OP didn't ask a general question; the question is exactly what it is, nothing more, nothing less.

    I don't think he meant "is it either this option or that option (and nothing else)". I think he's just throwing out the first two ideas he thought of for how it could respond, but there could be other ways too that he's not thought of.
    That may be so, or it may not.

    The point is a) you don't know what he meant, and b) it's usually a pretty bad idea to not answer a question by answering a quite different one.

    He just wants to know how it would respond if the mass went somewhere non-local instantaneously. Yeah, big deal, it can't really do that - we get it already. But if it did blip out, disappear, teleport, whatever - then what would happen? How could space-time respond to such a change?
    So how do you think my suggested answer fails?

    Here it is again:

    "Would space-time get disturbed like the wake and bow wave from a boat [...] or oscillate like the air around an implosion if said planet/star was made to disappear?"

    Space-time is a concept introduced by Einstein, and is central to his hugely successful theory of general relativity (GR). AFAIK, the concept does not exist outside GR, or possible extensions to it.

    Now in GR, mass-energy cannot be made to disappear; in fact, GR makes no sense at all if mass-energy is not conserved.

    So your question is equivalent to asking what happens to something which exists only in a theory, assuming the theory is hopelessly (internally) inconsistent.

    And the answer to such a question is ... that the question is meaningless (and so you can make up any answer you like).

    Of course, you could change the question somewhat, and add that in disappearing the planet/star conserved mass-energy! If you did that, then the answer to your question would be "It depends"; specifically, it depends on the details of how the disappearing is accomplished (and it is not possible to answer the question without those details).

    Alternatively, you could ask what would happen in some theory - not yet developed - that, like GR, incorporates the concept of space-time, but permits planet/star disappearances (of the non-conservation of mass-energy kind). And I'm sure you know the answer to that! (HINT: you need to say what that alternative theory is, before you could answer!)

    Speculation can be quite fun; however, here in the Q&A section of BAUT, there is speculation that cannot be answered (check out the BAUT rules if you don't know why).
    If we don't know, or can't tell, then just say so without the patronising attitude.
    Where, in my suggested answer (above) do you detect a "patronising attitude"?

    If we can hazard a guess based on what we know, then do that instead (which is what I did in my first post).
    But your "answer" doesn't, in fact, answer the question asked.

    Nothing wrong with trying to answer a question, but to deliberately ignore what are clearly the key parts of the question isn't, IMHO, a very helpful thing to do.

    Being deliberately obtuse about it isn't helping anyone though.
    Where, in my suggested answer (above) do you detect a "deliberately obtuse"?

  8. #68
    I can see I've caused a bit of spirited debate. Hope I can clarify...
    Q1) If the massive object was made to suddenly accelerate to a higher velocity, would this cause gravity waves like those a boat makes from it bow, and a wake from its stern?
    Q2) If (and I'm going to do it by invoking the hand of GOD!!!!!!!!!!! So there! :P Just use your imagination!) a planet was to be plucked out of existence, its mass suddenly went somewhere else, or converted to energy all at once, or any other mechanism where by the status quo of space-time curvature due to the presence of mass was instantly changed, would the response of the gravity wave be like a medium around an implosion.

    Sometimes the questions really are a "what if" which requires only the use of imagination and arguing about the "disappearance" was missing the point that I was interested in the behaviour of gravity and space-time, NOT the planet.
    Thanks for your time anyway.

  9. #69
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    Concerning the side question of how to answer a scientifically meaningless question, and still keep to BAUT's Q&A policy, I started a thread in a different section: Is BAUT's Q&A section becoming intimidating?

    That thread also attempts to address the question of whether any answer to a scientifically meaningless question can appear anything other than "obstructive, unhelpful, and intellectually snobbish".

    I hope those who've taken part in discussion of this OT topic, in this thread, will continue the discussion in the new thread.

  10. #70
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    Quote Originally Posted by Grahamshortuk View Post
    I can see I've caused a bit of spirited debate. Hope I can clarify...
    Q1) If the massive object was made to suddenly accelerate to a higher velocity, would this cause gravity waves like those a boat makes from it bow, and a wake from its stern?
    It would most certainly produce gravitational wave radiation (GWR).

    However, the form and nature of that radiation would be "like" the analogy you write in only the most tenuous way.

    GWR is a wave quite unlike the waves on water, or classical electromagnetic radiation (i.e. per Maxwell's equations) - if you're interested in learning more I (or someone else) can post some links to online material.

    The other aspect (well, another) is that GWR will propagate away from the source, at c, in all directions. This is quite unlike the analogy in your post. Generally it will not be isotropic (you know what that means by now, right?).

    Q2) If (and I'm going to do it by invoking the hand of GOD!!!!!!!!!!! So there! :P Just use your imagination!) a planet was to be plucked out of existence, its mass suddenly went somewhere else, or converted to energy all at once, or any other mechanism where by the status quo of space-time curvature due to the presence of mass was instantly changed, would the response of the gravity wave be like a medium around an implosion.
    Space-time is a concept introduced by Einstein, and is central to his hugely successful theory of general relativity (GR). AFAIK, the concept does not exist outside GR, or possible extensions to it.

    Now in GR, mass-energy cannot be made to disappear; in fact, GR makes no sense at all if mass-energy is not conserved.

    So your question is equivalent to asking what happens to something which exists only in a theory, assuming the theory is hopelessly (internally) inconsistent.

    And the answer to such a question is ... that the question is meaningless (and so you can make up any answer you like).

    Of course, you could change the question somewhat, and add that in disappearing the planet/star conserved mass-energy! If you did that, then the answer to your question would be "It depends"; specifically, it depends on the details of how the disappearing is accomplished (and it is not possible to answer the question without those details).

    Alternatively, you could ask what would happen in some theory - not yet developed - that, like GR, incorporates the concept of space-time, but permits planet/star disappearances (of the non-conservation of mass-energy kind). And I'm sure you know the answer to that! (HINT: you need to say what that alternative theory is, before you could answer!)

    Sometimes the questions really are a "what if" which requires only the use of imagination and arguing about the "disappearance" was missing the point that I was interested in the behaviour of gravity and space-time, NOT the planet.
    Thanks for your time anyway.
    Speculation can be quite fun; however, here in the Q&A section of BAUT, there is speculation that cannot be answered (check out the BAUT rules if you don't know why).

    And I hope my answer (above) directly addresses your point.

    You change the rules of the universe dramatically, and the best theory you have to explain those rules becomes pure imagination. Along with the theory, the very concepts "gravity and space-time" also become pure imagination.

    So, as in 01101001's pithy and pertinent post:

    If [impossible hypothetical] then [unpredictable result].

    Plug in your favorites. It matters not.

  11. #71
    I would be interested in the links to further reading, thank you. And I will be paying attention to the development of the thread that this post has inspired, as, speaking for myself, an interested but obviously non academic non expert, I have detected an air of elitism, a condescending tone, if you will, in some of the threads, and not just the ones I am involved with.

  12. #72
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    Quote Originally Posted by Grahamshortuk View Post
    I would be interested in the links to further reading, thank you.
    OK, I'll dig up some.

    It will take me quite a while, because explaining the details of GWR at the level you are interested in, AND within the bounds of your current understanding of GR, is not easy.

    And I will be paying attention to the development of the thread that this post has inspired, as, speaking for myself, an interested but obviously non academic non expert, I have detected an air of elitism, a condescending tone, if you will, in some of the threads, and not just the ones I am involved with.
    (bold added)

    Now that you have my answer (to your second question, in the OP) in hand, would you like to have a go at answering it yourself?

    I am most curious to know what comes across as "an air of elitism, a condescending tone" (and what doesn't).

  13. #73
    Re: tones.
    Its not rare to see comments after a quote along the lines of; nonesense. Gibberish. Clearly don't know what you are talking about. Why don't you learn xyz before asking about abc. Etc.
    Well that sort of thing does not read kindly to those of us who are not as educated as others and want to find out about abc but didn't know that xyz was a pre-requisite, or even that xyz was a "thing" to be known in the first place. If the purpose here is for those who ask questions to gain knowledge from those that have it, that clearly some users are adopting the role of teacher, and should consider their audience according to their individuality.
    Perhaps though I am being too harsh, and it's an unavoidable human trait to completely erradicate any traces of frustration a teacher may have with their pupils level of understanding compared with their own. But sometimes it does read a bit more abbrasively than that.
    That's all I'm going to say on the subject here.

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    Perhaps another way to frame the problematic issues that have arisen around how the OP is framed is that one can interpret the OP in two very different ways:
    1) What would happen if the planet disappeared, without accounting for any physically possible process that could have made it disappear (that would be like saying the planet "just disappeared"),
    2) What would happen if the planet disappeared, including whatever physically possible processes could make that happen (like, a thermonuclear explosion in its core that converted mass to kinetic energy, and following the debris that blasted out in a momentum-conserving way).

    The second question is the only one that science can answer, and even then only after a particular theory is chosen to do so, even though if it is a much more complicated question. What isn't clear from the OP is whether the OPer is willing to accomodate that more complicated answer, or if they are expressly requiring that it be left out of their "thought experiment." The problem with the latter approach is that a "thought experiment" really doesn't mean allowing any old impossible thing to happen, that's just not at all what a thought experiment is. The "thought" part just means that we are not actually going to be able to build the technology to actually do the experiment, it does not mean that the experiment somehow exists only in our minds and has nothing to do with the real world. The latter is not a "thought experiment", it is a "flight of fancy", and it is not at all clear that there are any worthwhile scientific lessons that can be gleaned from flights of fancy.

    Note also that it is not insulting to the OPer to point out that form (1) is a flight of fancy, because it's not even clear if form (1) is indeed the relevant one for the OP, and what's more, establishing a difference between thought experiments and flights of fancy is not insulting to anyone, it is simply a crucial step in understanding what scientific answers actually are. Same for Nereid's key point that all scientific answers must be framed in the form of either an experimental outcome, or else they must choose a particular theory (and of course only the latter is available for thought experiments). So no OPer should ever object "I don't want the answer from some theory that I have to make my question consistent with, I want the answer independent of any theory so that I can just ask anything I like without constraint." You can certainly ask anything you want, and please do, but also expect that the necessary constraints to make the question relevant to a science forum will then have to be pointed out to you (politely and constructively, as was generally true even in this thread, yes it was-- only a few exceptions). Would you want it any other way?

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    Quote Originally Posted by Nereid View Post
    The other aspect (well, another) is that GWR will propagate away from the source, at c, in all directions. This is quite unlike the analogy in your post. Generally it will not be isotropic (you know what that means by now, right?).
    Just checking: did you mean "not isotropic"? It doesn't sound quite right in the context of the previous sentence; admittedly "in all directions" doesn't necessarily mean "equally in all directions" but it loosely implies it.

  16. #76
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    Quote Originally Posted by Strange View Post
    Just checking: did you mean "not isotropic"? It doesn't sound quite right in the context of the previous sentence; admittedly "in all directions" doesn't necessarily mean "equally in all directions" but it loosely implies it.
    Good point.

    If you could measure the intensity of the GWR at all points on a sphere centred on the event, you'd find that the intensity would not be the same (for all points).

    As an analogy, think of supernovae; the observed intensity of light (or x-rays or radio or ...) will be different in different directions, at least for some supernovae.

    Or GRBs: as far as we know, the gammas are beamed (are highly anisotropic), though there may be gammas emitted in all directions.

  17. #77
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    Quote Originally Posted by Grahamshortuk View Post
    Re: tones.
    Its not rare to see comments after a quote along the lines of; nonesense. Gibberish. Clearly don't know what you are talking about. Why don't you learn xyz before asking about abc. Etc.
    Well that sort of thing does not read kindly to those of us who are not as educated as others and want to find out about abc but didn't know that xyz was a pre-requisite, or even that xyz was a "thing" to be known in the first place. If the purpose here is for those who ask questions to gain knowledge from those that have it, that clearly some users are adopting the role of teacher, and should consider their audience according to their individuality.
    Perhaps though I am being too harsh, and it's an unavoidable human trait to completely erradicate any traces of frustration a teacher may have with their pupils level of understanding compared with their own. But sometimes it does read a bit more abbrasively than that.
    That's all I'm going to say on the subject here.
    There's likely a lot going on here.

    There are many examples of BAUTians continuing to try, by hook or by crook, to smuggle their ATM ideas into Q&A threads; if sometimes a long-standing member's frustration at this comes out in words like those you cite, rather than clicking the report button, well, it may not be excusable, but is certainly understandable.

    There are also plenty of examples of innocent questions being asked in very aggressive ways, even if there is no intent to promote ATM idea. And it escalates when such an OPer responds to careful, polite answers (that they do not understand) with anger, or even more demonstrative declarations, or similar. Humility is just as much required of an innocent OPer as of those who answer questions.

    I think answering questions in a consistent, and consistently patient, way, here in the Q&A section of BAUT is something seasoned teachers are likely best equipped to do ... but there are, I suspect, precious few of those among the regulars here. And even for a seasoned teacher, the anonymity of BAUT makes it harder to answer consistently (how do you accurately judge the level of an OPer's understanding of physics, for example?).

  18. #78
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    Quote Originally Posted by Ken G View Post
    Perhaps another way to frame the problematic issues that have arisen around how the OP is framed is that one can interpret the OP in two very different ways:
    1) What would happen if the planet disappeared, without accounting for any physically possible process that could have made it disappear (that would be like saying the planet "just disappeared"),
    2) What would happen if the planet disappeared, including whatever physically possible processes could make that happen (like, a thermonuclear explosion in its core that converted mass to kinetic energy, and following the debris that blasted out in a momentum-conserving way).

    The second question is the only one that science can answer, and even then only after a particular theory is chosen to do so, even though if it is a much more complicated question. What isn't clear from the OP is whether the OPer is willing to accomodate that more complicated answer, or if they are expressly requiring that it be left out of their "thought experiment." The problem with the latter approach is that a "thought experiment" really doesn't mean allowing any old impossible thing to happen, that's just not at all what a thought experiment is. The "thought" part just means that we are not actually going to be able to build the technology to actually do the experiment, it does not mean that the experiment somehow exists only in our minds and has nothing to do with the real world. The latter is not a "thought experiment", it is a "flight of fancy", and it is not at all clear that there are any worthwhile scientific lessons that can be gleaned from flights of fancy.

    Note also that it is not insulting to the OPer to point out that form (1) is a flight of fancy, because it's not even clear if form (1) is indeed the relevant one for the OP, and what's more, establishing a difference between thought experiments and flights of fancy is not insulting to anyone, it is simply a crucial step in understanding what scientific answers actually are. Same for Nereid's key point that all scientific answers must be framed in the form of either an experimental outcome, or else they must choose a particular theory (and of course only the latter is available for thought experiments). So no OPer should ever object "I don't want the answer from some theory that I have to make my question consistent with, I want the answer independent of any theory so that I can just ask anything I like without constraint." You can certainly ask anything you want, and please do, but also expect that the necessary constraints to make the question relevant to a science forum will then have to be pointed out to you (politely and constructively, as was generally true even in this thread, yes it was-- only a few exceptions). Would you want it any other way?
    I would really like to have EDG read this, carefully, and respond, thoughtfully.

    IMHO, it summarises well a point EDG does not, yet, seem to have grasped.

  19. #79
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    Quote Originally Posted by Grahamshortuk View Post
    I would be interested in the links to further reading, thank you. And I will be paying attention to the development of the thread that this post has inspired, as, speaking for myself, an interested but obviously non academic non expert, I have detected an air of elitism, a condescending tone, if you will, in some of the threads, and not just the ones I am involved with.
    http://math.ucr.edu/home/baez/einstein/einstein.pdf

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    Good grief...tone and attitude... more considerations to ponder while my mind races away on yet another tangent.
    I am only just in control now and, theres room for doubt. Its only right that a thread sort of evolves through the subject mater...
    As I struggle to find the words to use. If a object we previously viewed were to vanish. No thats not this question is it.
    This OP wants to know if gravity waves or other disturbance might be detectable. I except this is his question. Trouble being that I can not contemplate such an event. So any of its effects are all pair shaped.. I can not offer a better answer than NO. Is there a better answer ?

  21. #81
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    As the OP bowed out after post # 6, and this has turned into an extended discussion among others, I've move the thread to Astronomy from Q&A. If someone has concerns about either the move or the new location, please report my post.
    At night the stars put on a show for free (Carole King)

    All moderation in purple - The rules

  22. #82
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    Quote Originally Posted by Nereid View Post
    Quote Originally Posted by Grahamshortuk
    And I will be paying attention to the development of the thread that this post has inspired, as, speaking for myself, an interested but obviously non academic non expert, I have detected an air of elitism, a condescending tone, if you will, in some of the threads, and not just the ones I am involved with.
    (bold added)

    Now that you have my answer (to your second question, in the OP) in hand, would you like to have a go at answering it yourself?

    I am most curious to know what comes across as "an air of elitism, a condescending tone" (and what doesn't).
    Bump.

    If you're still participating Grahamshortuk, I really would like to see how you'd answer your second question.

  23. #83
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    Quote Originally Posted by Grahamshortuk View Post
    I would be interested in the links to further reading, thank you.
    I see that DrRocket has provided a good link.

    I also provided you some links, in a response to a post of yours, in a different thread. What did you make of that material?

  24. #84
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    If anyone is still reading this thread, you may be interested in Thought experiments, "what-if"s, imagination, and science.

  25. #85
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    Quote Originally Posted by Grahamshortuk View Post
    Re: tones.
    Its not rare to see comments after a quote along the lines of; nonesense.
    There are three instances of this word, in this thread (not counting this post and ones which quote it). The first was by EDG, and his post can accurately be described using this word. The next is also by EDG, and it's a classic strawman (the third instance is someone quoting EDG, and calling him to task for deliberate distortion).

    Gibberish.
    There is one instance of this word, in this thread (not counting this post and ones which quote it). It is by DrRocket. In context (you need to read the many north-DrRocket dialogues to understand this), it is entirely appropriate.

    Clearly don't know what you are talking about.
    This phrase does not appear in this thread (not counting this post and ones which quote it).

    Why don't you learn xyz before asking about abc.
    The phrase "Why don't you" does not appear in this thread (not counting this post and ones which quote it).

    Etc.
    Well that sort of thing does not read kindly to those of us who are not as educated as others and want to find out about abc but didn't know that xyz was a pre-requisite, or even that xyz was a "thing" to be known in the first place.
    No doubt that could be so.

    However, as none of the words, or phrases, you provide were actually used in this thread (except by EDG, who used "nonsense" in a quite different way, and DrRocket, who used "gibberish" in an entirely appropriate way), your point is rather moot, don't you think?

    If the purpose here is for those who ask questions to gain knowledge from those that have it, that clearly some users are adopting the role of teacher, and should consider their audience according to their individuality.
    I would be interested to hear from you further on this.

    Specifically, where, in this thread, have you seen evidence of someone not "considering their audience according to their individuality"?

    Perhaps though I am being too harsh, and it's an unavoidable human trait to completely erradicate any traces of frustration a teacher may have with their pupils level of understanding compared with their own. But sometimes it does read a bit more abbrasively than that.
    That's all I'm going to say on the subject here.
    I do hope you'll comment on what I found.

    I am most interested to know why you chose to use words and phrases that are not to be found in this thread, to make your point.

  26. #86
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    Since this thread has turned into nothing but Nereid's posts about words and semantics, I've closed it.
    At night the stars put on a show for free (Carole King)

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