Strange Posted August 8, 2016 Posted August 8, 2016 I looked at the definition of TENSORS , they are Scary Sounding . But Pure . But not REAL not necessarily APPLIED on anything , just an operation . And yet they get called a MATHMATICAL OBJECT. ( glug ! ) You can't says modern science is wrong just because you find the math scary. Tensors can be used in pure mathematics. Or they can be used in applied mathematics. They are applied in many areas. One of which is describing mass, energy, etc. and how they produce the effects we call gravity.
Mike Smith Cosmos Posted August 8, 2016 Posted August 8, 2016 (edited) That would require that the field be a physical thing, rather than a mathematical construct. But that's not the real issue. An EM wave makes its own fields. It does not require that a separate field be present. . But I thought we had established , that the universe of space had an electromagnetic field present from one end of the universe to the other , as part of its construction . And individual electro-magnetic photons as waves , came wandering through by interaction with the main universal field or zooming through from wherever they came from . You can't says modern science is wrong just because you find the math scary. Tensors can be used in pure mathematics. Or they can be used in applied mathematics. They are applied in many areas. One of which is describing mass, energy, etc. and how they produce the effects we call gravity. .I am not saying it's wrong because it's scary . I am saying it's hard to call something ' Real ' . And ' object ' sounds real . If it is real , that's fine , we can wave it about like a bit of carpet . ( or induce some steady field to become disturbed and oscillate about for a cycle or two . ) But if it's just , so much abstract maths written in a computer memory somewhere we can't wave it around ? Or it can't wave itself about ? It's just so much dynamic information . Surely? Mike Edited August 8, 2016 by Mike Smith Cosmos
geordief Posted August 8, 2016 Posted August 8, 2016 One of the conspiracy theory objections to the moon landings is that the flag is waving in the vacuum. (The conspiracy theorists insist it requires an atmosphere, so it must have been filmed on earth.) So unless you are a part of that cabal, you can see we have empirical evidence of a fabric waving in a vacuum. Has the waving/motion reduced over time? Are there dampening electro-magnetic forces within the fabric and between the fabric and the pole ? Would the moons gravity also act as a dampener?
Strange Posted August 8, 2016 Posted August 8, 2016 I am not saying it's wrong because it's scary . I am saying it's hard to call something ' Real ' . And ' object ' sounds real . If it is real , that's fine , we can wave it about like a bit of carpet . ( or induce some steady field to become disturbed and oscillate about for a cycle or two . ) But if it's just , so much abstract maths written in a computer memory somewhere we can't wave it around ? Or it can't wave itself about ? It's just so much dynamic information . Surely? The math is just a description of what happens (what we observe happening).. It is just a more accurate version of "space-time is curved by the presence of mass". So much more accurate that it becomes useful. Whether that description describes something real or not is a matter of personal opinion (which depends, mainly, on what that person means by the word "real"). So it is irrelevant whether a tensor is a real "object" (that is just a bit of mathematical terminology that could be equally well applied to variable called "x" or the number 5 - they are both "objects" in mathematics). What is important (to you) is whether the thing that the tensors describe is real. Just say "yes" so we can all go home!
Mike Smith Cosmos Posted August 8, 2016 Posted August 8, 2016 (edited) . Yes ! My CONCLUSIONS ( whether rightly or wrongly ) is having listened to the whole thing is :- That there are in the universe two distinct facilities here ( GRAVITATIONAL , AND ELECTRICAL ) . Both being very different in their nature and operation . Yet both having or , are , a Medium/ Aether for their operation. In both distinctly different cases the medium is of the same nature material concerned. Namely :- with firstly ELECTRO MAGNETISM is present throughout the universe/ space as a medium for light and other ELECTRO MAGNETIC WAVES . As an Electro -Magnetic FIELD. The medium is Electromagnetic . The waves are electromagnetic , being in fact interactions within the universe wide electromagnetic field . Field , medium and wave are of a similar nature . Or in fact fascits of the same thing . GRAVITATIONAL ACTIVITY Is present throughout the Universe/space as a medium for matter and GRAVITATIONAL WAVES. As a Gravitational FIELD . The medium is Gravitational Matter ( Mass) spread across the whole universe. The waves are gravitational , being in fact ' pertabations or waves ' within the universe wide Gravitational field generated by all the mass large and small across the whole universe. Field and wave and medium are of a similar nature . Or in fact fascits of the same thing . Mike Edited August 8, 2016 by Mike Smith Cosmos
swansont Posted August 8, 2016 Posted August 8, 2016 But I thought we had established , that the universe of space had an electromagnetic field present from one end of the universe to the other , as part of its construction . And individual electro-magnetic photons as waves , came wandering through by interaction with the main universal field or zooming through from wherever they came from . The ambient field inside of a conducting shell is zero. And yet you can have photons in there. Has the waving/motion reduced over time? I'm sure it has. Are there dampening electro-magnetic forces within the fabric and between the fabric and the pole ? Yes, they would ultimately be EM in nature, as they are related to the bonds between the molecules. Would the moons gravity also act as a dampener? That would undoubtedly have some effect.
Mike Smith Cosmos Posted August 8, 2016 Posted August 8, 2016 (edited) The ambient field inside of a conducting shell is zero. And yet you can have photons in there. ..Not too sure the relevance of your comment here? Could you explain ? Thanks Mike Edited August 8, 2016 by Mike Smith Cosmos
swansont Posted August 8, 2016 Posted August 8, 2016 . Not too sure the relevance of your comment here? Could you explain ? Thanks Mike You are requiring an ambient field, and there is no ambient field inside of a conductor. There is evidence falsifying your position. A photon does not need some other field to be present in order to propagate.
MigL Posted August 8, 2016 Posted August 8, 2016 (edited) The EM field he is talking about would be the QED field which gives rise to charged particles and photons, Swansont. This was a 'gimme' to Mike in the hope of stopping this discussion before it went to 10 pages ( now at 35 and rising ). But it doesn't have photons zipping through it Mike, excitations in the field ARE the photons. As for your ideas regarding the medium for gravitational waves being the masses that are scattered throughout the universe, Mike, just like the fibers in the carpet... How does the wave then get from one mass to another ? There has to be a mass in between to wave, doesn't there ? And how does the wave get to the in-between mass? There has to be mass continuously throughout the universe ? See how silly your idea quickly becomes ? But if that thing you don't like, space-time, because it is just abstract geometry; if we allow it to have energy ( virtual particles are borrowed energy ) then it has the equivalent of mass. And we can 'consider' it a continuous mass throughout the universe. Then we do have 'mass-energy' as a 'medium'. Now can we put this to rest ? Edited August 8, 2016 by MigL
Mike Smith Cosmos Posted August 8, 2016 Posted August 8, 2016 You are requiring an ambient field, and there is no ambient field inside of a conductor. There is evidence falsifying your position. A photon does not need some other field to be present in order to propagate. Well , I must say at first pass , what you say about photons inside a conducting / conductor. Sound counter to my proposal of the need for Medium/ AETHER for photon propagation . I do however wonder whether what you are talking about is ( total internal reflection , like in a fibre optic cables. Or the sort of propagation in microwave ( metal waveguides ) . Mike
swansont Posted August 8, 2016 Posted August 8, 2016 Well , I must say at first pass , what you say about photons inside a conducting / conductor. Sound counter to my proposal of the need for Medium/ AETHER for photon propagation . I do however wonder whether what you are talking about is ( total internal reflection , like in a fibre optic cables. Or the sort of propagation in microwave ( metal waveguides ) . Mike I said conductor, so no, I'm talking about fiber optics. I said conducting shell, so not a waveguide, either.
Mike Smith Cosmos Posted August 8, 2016 Posted August 8, 2016 (edited) The EM field he is talking about would be the QED field which gives rise to charged particles and photons, Swansont. This was a 'gimme' to Mike in the hope of stopping this discussion before it went to 10 pages ( now at 35 and rising ). But it doesn't have photons zipping through it Mike, excitations in the field ARE the photons. But if that thing you don't like, space-time, because it is just abstract geometry; if we allow it to have energy ( virtual particles are borrowed energy ) then it has the equivalent of mass. And we can 'consider' it a continuous mass throughout the universe. Then we do have 'mass-energy' as a 'medium'. Now can we put this to rest ? . Trying to respond sequentially to your points . ( I haven't got hold of this quote by quote method that most use ) so first : BEGINNING OF POINTS --------------------- POINT A --------------------- "But it doesn't have photons zipping through it Mike, excitations in the field ARE the photons." Yes , I understand that , excitation are the photons ( it's just a wave packet of energy ) . Just like the wave on the sea coming ashore. The water has not come from far out to sea , only the packet of energy comes to the coast . True the final break at the shore is a big ( back and forward ) , but thats just due to running out of depth. I am quite happy the medium and the packet ,being of the same nature , or are the same . ------------------- POINT B ------------------- As for your ideas regarding the medium for gravitational waves being the masses that are scattered throughout the universe, Mike, just like the fibers in the carpet... How does the wave then get from one mass to another ? There has to be a mass in between to wave, doesn't there ? And how does the wave get to the in-between mass? There has to be mass continuously throughout the universe ? See how silly your idea quickly becomes ? My reply :- Well all I was suggesting was that something ' matter like ' , in other words had some of the characteristics of matter, mass , even if not all. And it acted as a medium to ALL matter . That could be dark matter , because . I understand some of its particles are very small , but none the less respond to all matter ( if I have it right ) . So when BIG ISSUES come along say in Galaxy formation , or colliding black holes . This medium ( dark matter responds ) throughout the entire universe. I do not think particles have be touching each other to act as an effective medium. In fact I am not sure that any particles are rubbing shoulders throughout the universe . They seem to interact without touching most of the time , don't they ? ------------------------ POINT. C ------------------------ But if that thing you don't like, space-time, because it is just abstract geometry; if we allow it to have energy ( virtual particles are borrowed energy ) then it has the equivalent of mass. And we can 'consider' it a continuous mass throughout the universe. Then we do have 'mass-energy' as a 'medium'. Then , what I said in the previous paragraph is again applicable ? (About interacting without touching , necessarily . ) ? ------------------------------ END OF POINTS ------------------------------ Mike Edited August 8, 2016 by Mike Smith Cosmos
disarray Posted August 8, 2016 Posted August 8, 2016 (edited) The math is just a description of what happens (what we observe happening).. It is just a more accurate version of "space-time is curved by the presence of mass". So much more accurate that it becomes useful. Whether that description describes something real or not is a matter of personal opinion (which depends, mainly, on what that person means by the word "real"). So it is irrelevant whether a tensor is a real "object" (that is just a bit of mathematical terminology that could be equally well applied to variable called "x" or the number 5 - they are both "objects" in mathematics). Speaking for laypersons, I can see that it is often unclear as to what might have some objective correlative that one designates as real. Even quantum physicists have different opinions as to whether one should continue to ask such questions as to whether the position of an electron is definite before being observed, or to take the more practical/applied approach of to just "shut up and calculate." There seems to be a difference between appearance and reality in many cases (though sometimes they are the same) as with the apparent curvature of a stick in a beaker of water. In Relativity, it makes sense to me that (from the pov of a person on earth looking at the clock on a rocket speeding away at near the speed of light) that the clock would just appear to slow down, but then there is the further claim that time actually slows down so that the returning traveler will not be as old as his companion who stayed on earth. Similarly (by virtue of the equivalence principle), one wonders whether (space)time itself actually slows down in a gravitational well, or whether there is some change in the velocity at which EM waves (of any clock) are moving, even though, for all practical purposes, it doesn't make any difference. Also, there is some confusion as to whether space(time) actually "curves" in the usual sense of the word , e.g., light passing by the sun, or whether saying that space curves is just a mathematical convention that shouldn't be taken literally. I can see though that it doesn't matter all that much as to what we mean when we say that spacetime "curves," as long as we can improve the accuracy of our GPS/satellite systems. Semantics. Indeed, the two main schools of thought with regards to whether reality is fundamentally mathematical in nature is the Platonic approach (e.g., Godel) who sees our mathematical systems as a reflection of the mathematical structure inherent in the universe, and the constructionist/paradigm approach in which mathematics is seen to effectively (to varying degrees as with competing superstring theories) map the structures in the universe, but in a way that is arbitrary and never absolute or definitive. Certainly one hears that much of superstring theory "works," but that people have no idea whether 'reality' has 'really' 10 or 11 dimensions or not. On the other hand, it does seem that science sometimes does take a step forward if we can more accurately identify something (however physical or ephemeral) that matches up with the math model that works so well and perhaps, in some cases, help us to understand the nature of cauality/acausality in a situation a little better, e.g., the discovery of CBR to help validate Big Bang theory, the discovery of the Higgs Boson, and the possible discovery of gravitons. In any case, I think that focusing on semantics (unlike perhaps more vague aspects of philosophy such as ontology which asks why things are as they are) is useful. For example, there does seem to be some confusion even in this thread as to what a "field" is, or rather, what different meanings it might take on depending upon the context in which it is used. Thus, Mike might agree that there is a gravitational "field," but then say "hang on a moment" when you clarify that the field of which you speak is just a mathematical grid with mathematical metrics/tensors, and says nothing about the 'ingredients' of gravity or gravitational waves beyond that. In a recent post, it seems to me, that he is saying that the EM field has so many properties that we can think of it as a (physical?) medium, so why not just say the same thing about the gravitational field? My own wild stab at putting a basic label on the word, "gravitation" is to agree that it is just a term for what we see happening in and to spacetime with respect to factors such as mass/energy momentum, and I personally would be "satisfied" with that and everyone can go home. I do think, as an aside, that, in accordance with various quotes I have posted recently, that spacetime is inextricably and ineluctably bound up with gravity and that gravity is similarly bound up with energy (levels), so that one might suggest that one is referring to some sort of "field" of energy when one speaks of spacetime curvature, gravitation, or gravitational waves. But even if this is an acceptable statement, however simplistic, one might further ask, perhaps somewhat obsessive/compulsively, what is "energy" or "mass/energy," be it with reference to EM or gravitational waves, and here, apart from describing their respective characteristics, I would agree is the end of the line, and a scientist can do no more and should not be expected to do any more than to say that 'it is what it is'. Edited August 8, 2016 by disarray
MigL Posted August 9, 2016 Posted August 9, 2016 (edited) No Mike. The gravitational wave medium cannot be particulate. Even dark matter interacts gravitationally. So how does the gravitational interaction get from one particle to another if there is no medium between the particles of dark matter... Can't you just be happy with space-time geometry as the field, and the medium To Disarray... Even with the equivalence principle the speed of light is invariant. Light is massless and constrained to move at the SoL. However light is a wave, and has a time varying amplitude. As such it can be considered a periodic clock signal ( the spacing between the peaks of the wave ), and yes, we do find a time variance in the signal when comparing signals from different depths in a gravitational well. A signal from deeper in the well will have the time between amplitude pulses stretched, or dilated, compared to a signal coming from higher up in the well. Notice that this is equivalent to a wavelength increase, or red-shift. Reality has nothing to do with dimensions. It is what affects you, i.e. what you measure. Edited August 9, 2016 by MigL
disarray Posted August 9, 2016 Posted August 9, 2016 However light is a wave, and has a time varying amplitude. As such it can be considered a periodic clock signal ( the spacing between the peaks of the wave ), and yes, we do find a time variance in the signal when comparing signals from different depths in a gravitational well. A signal from deeper in the well will have the time between amplitude pulses stretched, or dilated, compared to a signal coming from higher up in the well. Notice that this is equivalent to a wavelength increase, or red-shift. Very interesting. I will try to read up on this? Any suggested links. As per Maxwell's claim that everything is ultimately made up of things (e.g., EM waves) traveling at SoL, it makes sense to read that the metabolic processes as well as the ship as well as the clock in the traveling space ship "slows down" (in the twin scenario explaining Relativity). Could one similarly explain this effect in terms of the amplitude shift you mention here. Reality has nothing to do with dimensions. It is what affects you, i.e. what you measure. Again, this suggests that the Reality that is beyond our models and senses is a (noumenal) unkown with which we can't and shouldn't concern ourselves, though our models may improve. Ultimately this statement is tautological, and states that we can't know more than we know. I am reminded of a metaphor used in psychology to the effect that one cannot really see oneself objectively because one is so involved with ones own prejudices, background, and other factors affecting ones point of view, which is that "One cannot read the label if one is in the bottle."
Mike Smith Cosmos Posted August 9, 2016 Posted August 9, 2016 (edited) . They all went home . And left me standing by the Roadside ! And I am left ,wondering where my vehicle has disappeared to ? -------------- --------------------- ----------------- Somebody found him ' days later ' , still sitting on the grass verge , beside the road , dusty, ..muttering , saying ...over and over again ... ... " Yes but .." What.. is .. 'actually' there ?." . .. ..and gazing into the sun, ...... ..... Or was he hearing voices , asking him ...... ........ " what are these medium , you speak of ? " ........ these ..." Gravity waves and the Aether ? " But by this time , he had gone .. ' Stark staring bonkers ...' Lost the plot ! Mike Edited August 9, 2016 by Mike Smith Cosmos
Mike Smith Cosmos Posted August 11, 2016 Posted August 11, 2016 (edited) .Today on the Beach at Budleighsalterton South Devon , on the 200,000,000 year old pebble beds, the bed of a supercontinent massive River bottom . . . Matter Stones set in slow moving , matter gritty sand . Covered with energetic splashy fast moving waves of water in an emense sea of water with Enough Energy to power a world . He thinks of two distinct things . 1. The universe is full of matter , of various sized mass . Spread out like an ocean floor which acts as a base to the oceans , and similarly the Base structure of the Universe, and all that happens in 'her' . 2. The universe is full of Energy , of various waves and ripples. Spread about space , carrying the total cacophony of light and electro magnetic waves and energy to power a Universe . These two DIFFERENT , Eternal Enterprises ,( MATTER and ENERGY ) make up our UNIVERSE. . So different , separate , yet so complementary for existence. Mike Edited August 11, 2016 by Mike Smith Cosmos
studiot Posted August 11, 2016 Posted August 11, 2016 (edited) It is what affects you, i.e. what you measure. To borrow a phrase "Be careful what you measure, It may come true!" When I was growing up there was a black and white TV programme called "Stranger than fiction" Later I worked in the Saudi desert where survey parties observed (measured) negative vertical angles at both ends of some observation lines. Reality was of course, somewhat different. Edited August 11, 2016 by studiot
Mike Smith Cosmos Posted August 11, 2016 Posted August 11, 2016 Later I worked in the Saudi desert where survey parties observed (measured) negative vertical angles at both ends of some observation lines. Reality was of course, somewhat different. What does this mean , quite " negative verticals angles " ? Mike
Mike Smith Cosmos Posted August 18, 2016 Posted August 18, 2016 (edited) .. Yes, but if space-time is this grid , that gets curved by mass. Matter . In various ways , as illustrated . The gravitational field which is presumably space -time itself ? Must be something ? It can't be nothing, as curving nothing would be meaningless. Unless it was pure geometry. Then it would be nothing but would not be " the gravitational field , (as space-time ). . If this were so? Then space time itself as a gravitational field , would BE, or constitute the medium. In other words as the ORIGINAL posting states " Gravity waves and the aether" The aether is ' space time ' , ' the gravitational field ' ? Is that not so ? It would appear ( by looking at the two diagrams above) ,it is , :- that Mass, Matter , pulls the two dimensional state, into a third dimensional state? And in so doing invokes the production of a gravitational attractive field ? And that Gravitational Waves are in fact the ripples created in this two dimensional state , to become , :- " Gravity waves , in three dimensions travelling out in all directions across ' space time ' ( the aether) ? Does this sound right ? Mike Edited August 18, 2016 by Mike Smith Cosmos
Strange Posted August 18, 2016 Posted August 18, 2016 It would appear ( by looking at the two diagrams above) ,it is , :- that Mass, Matter , pulls the two dimensional state, into a third dimensional state? And in so doing invokes the production of a gravitational attractive field ? No that is not correct. The drawing shows 2 dimensions just because it is easier than trying to represent 4, or even 3. The curvature occurs in 4 dimensions of space-time. (And does not require a 5th dimension)
Mike Smith Cosmos Posted August 18, 2016 Posted August 18, 2016 (edited) No that is not correct. The drawing shows 2 dimensions just because it is easier than trying to represent 4, or even 3. The curvature occurs in 4 dimensions of space-time. (And does not require a 5th dimension) O.k. I thought that might be something like the case . So is it 3 dimensions of space and 1 of time ( as in space-time ) ? Or is it more correctly :- 3 dimensions of space-time , where each of the three dimensions say , x,y,z dimensions of space X coordinate , Y coordinate, Z coordinate T time are all categorised with separate space-time values , with individual coordinates, or is time the same across all the three spacial dimensions . Working as one distinct value of ' t ' across all 3 Spacial dimensions ? ( I probably have not worded that very clearly ) Mike Edited August 18, 2016 by Mike Smith Cosmos
Strange Posted August 18, 2016 Posted August 18, 2016 O.k. I thought that might be the case . So it's 3 dimensions of space and 1 of time ( as in space-time ) ? Mike Exactly.
Mike Smith Cosmos Posted August 18, 2016 Posted August 18, 2016 (edited) Exactly.So ! What about my question ? -------------------- Quote " If this were so? Then space-time itself as a gravitational field , would BE, or constitute the - ' medium. ' In other words as the ORIGINAL posting states " Gravity waves and the aether" The aether is ' space-time ' , ' the gravitational field ' ? Is that not so ? " Unquote ? ------------------------------- If that were to be the case? Then the gravitational waves , would truly be said to be travelling in/on the medium ( or aether ) ? Would that therefore be so ? Mike Edited August 18, 2016 by Mike Smith Cosmos
Strange Posted August 18, 2016 Posted August 18, 2016 So ! What about my question ? -------------------- Quote " If this were so? Then space-time itself as a gravitational field , would BE, or constitute the - ' medium. ' In other words as the ORIGINAL posting states " Gravity waves and the aether" The aether is ' space-time ' , ' the gravitational field ' ? Is that not so ? " Unquote ? ------------------------------- If that were to be the case? Then the gravitational waves , would truly be said to be travelling in/on the medium ( or aether ) ? Would that therefore be so ? Mike Yes. Me and many others said this some time ago. (Although, personally, I think using the word "aether" is unnecessarily confusing as it was originally used for something completely different.)
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