JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 You guys are fun...I think I need to go read lots of forums posted here...there's lots of new perspectives to take in...GR is a crazy cool thing...but seriously, to make it work as a model for our universe, we have to admit that we cant find 75 percent of the matter and energy that exists...its seem weird to allow 75 percent of your knowledge to be changed by something that doesn't work without changing 75 percent of what you know...In other words, one day, we may find the holes in GR that make it incomplete, and until that day, lots of folks will claim they aint there....but there is a huge hole...its called, "we better find 75 percent more of this stuff or this theory is broke"...We shall see if they find it...
Mordred Posted January 6, 2015 Posted January 6, 2015 (edited) Ya...the math itself is like a different dimension of understanding this stuff...I just know results of tests and experiments and what others have proved...But it does seem that the guys who dream stuff up are not always the ones who also prove that it's true. And even though Einstein had some outrageous math in quantum mechanics that could be explained to others, did anyone know he was right until experimentation proved it? We even had to get the experiments correct to get the results out of the experiment to match the math that was made...we keep getting the experiments closer and closer...but if relativity exists, it surely exists in these experiments we use as proof too...we cant judge spatial events without worry of relativistic error, we cant judge time without worry of relativistic error..Completing equations has never been proof of anything...proof beyond the equations was always sought...or created...I think uncertainty exists all over the place...certainly in my existence and thoughts...so I spit them out...its all we can do yknow...communicate... Ive been dying for someone to explain general relativity in their own words since I was in middle school....Everyone agrees that it describes the effects of a geometric distortion of spacetime...you may say it is nothing, but how does nothing have a name? and how do you warp something that is not anything? You cant warp nothing...You can in math, with theories...But you're gonna be hard pressed to show me the act of warping nothing...It kinda seems like a physical impossibility...but its happening all around us in this physical world? We have this dark matter that we cant detect and we theorize that it is further changing the geometry of spacetime, which IS nothing, because GR does NOT work in humongous galaxy clusters and such...so we have to find something else to make it work...instead of theorizing that spacetime is the corresponding trait to massenergy, and it actually contains energy, which makes it something and not nothing...and can now be bent...even though bending something by definition is compressing parts of it..and we may as well replace warp and bent with compress because that is the impetus of the gravitational geometrical effects called gravity...or, that is my theory... The dark matter, warping nothingness doesn't sit well with me...Which does not mean its wrong...If you can explain it without dark energy and warping nothingness, why not give it a serious look? I knew the gravity increased and the mass did not. I had mentioned it early in my writtings. You made the statement about mass being increased by compression. But since I cant figure out how to quote and respond with those little boxes, youll just have to scroll up to see your error. So you were wrong in your first statement? The bending warping twisting descriptives is descriptives of influence upon particles by gravity. Gravity can only influence particles. Energy does not exist on its own. Energy is a property of particles. Space is just volume filled with the particles of the universe. Between those particles there is empty volume gravity cannot influence a volume of nothing to influence. It influences the particles themself. It is a coordinate dependant model. In GR space time is a set of coordinates. It is the coordinates that gets warped and twisted etc.You guys are fun...I think I need to go read lots of forums posted here...there's lots of new perspectives to take in...GR is a crazy cool thing...but seriously, to make it work as a model for our universe, we have to admit that we cant find 75 percent of the matter and energy that exists...its seem weird to allow 75 percent of your knowledge to be changed by something that doesn't work without changing 75 percent of what you know...In other words, one day, we may find the holes in GR that make it incomplete, and until that day, lots of folks will claim they aint there....but there is a huge hole...its called, "we better find 75 percent more of this stuff or this theory is broke"...We shall see if they find it... Let's leave dark energy and dark matter for another thread. I can help you understand those. However would take too much in this thread. Which is on relativity. Look at my signature for my webpage there is some good articles there Edited January 6, 2015 by Mordred
Strange Posted January 6, 2015 Posted January 6, 2015 IF they can suggest that dark matter exists with no proof besides holes in their equations, 1. That isn't the reason that dark matter is hypothesized. I can't understand why people don't understand the concept of "evidence". 2. You say "The math has already been done" so you are using the same equations (therefore, with the same "holes"). So how can you claim "By the way, we don't need dark energy or dark matter anymore"? Either you are using the same maths and therefore need the extra mass represented by dark matter, or you have a new model which does away with the need for dark matter. If the latter, you need to show that your model reproduces the rotation curves of galaxies (and all the other evidence for dark matter). Imagination is great but if it doesn't match reality, it isn't science. If we are leaving a world where observation of physical objects is worthless and considered only a mathematical possibility, I wont be much good there... But it is you who is rejecting observation by claiming that dark matter is just "holes in the equations". At 45 years old, Im thinking about going back to college to study such subjects. Great idea. I did that in my 40s (and ended up in a new career). Newton never could have observed the objects falling at the same speed. Huh? This has been known since Galileo and the mathematical reasons shown by Newton (and confirmed by Einstein). But I only suggested that the latex grid model was essentially ridiculous and they still put it on the front of physics books. I would probably agree with that... And even though Einstein had some outrageous math in quantum mechanics that could be explained to others, did anyone know he was right until experimentation proved it? Actually, Einstein's work in quantum theory came after (to explain) the experiments. So in that case people were pretty sure he was right straight away (and hence the Nobel Prize). In the case of General Relativity, because it was derived directly from Maxwell's equations most people were convinced he was right even before any experiments were performed. Everyone agrees that it describes the effects of a geometric distortion of spacetime...you may say it is nothing, but how does nothing have a name? and how do you warp something that is not anything? You cant warp nothing... It is geometry (lengths, etc.) that are warped, not anything "physical". because GR does NOT work in humongous galaxy clusters and such... It works perfectly well. There have been and are attempts to explain dark matter by changing the rules about how gravity works. Unfortunately, no such theories match observation; even the best still need some dark matter. You made the statement about mass being increased by compression. Actually, he said that density increases. But since I cant figure out how to quote and respond with those little boxes Here, try this: http://www.scienceforums.net/topic/82164-the-quote-function-a-tutorial-in-several-parts/
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 I really wish I knew how to grab little bits of text and respond to them...but I don't...Mordred, with the amount of misquotes and mistakes on your part this evening, I don't think Ill be learning anything from you other than to make sure Im typing what I know when I type it...You have to admit...almost every explanation you gave was incorrect...Strange, you actually responded to only parts of my sentences...science doesn't work very well unless you observe fully before responding...I accept your apology In advance...The math works in certain frames of reference, or you might even consider them dimensions...Just like Newtonian gravity worked in certain frames of reference, but not all...Are you saying that they have evidence of dark matter and dark energy that isn't associated with making general relativity work in regards to universal expansion? I do believe I have a model that does away with the need for dark energy and dark matter...after all this talk of warping and bending and changing geometry in GR, how can someone say that space-time is homogenous? If we give spacetime the ability to clump together and spread out, influenced by the forces of gravity, then the need for dark matter and energy are gone and someone will have to start some new equations with these new realities in mind...not work with equations where you have to make up 75 percent of the universal force and atribute it to something you cant find...But yeah, when you make space uneven, things like conservation of momentum get very goofy...Anyway, Im totally loving the idea of finding some proof of dark matter or energy...references? Quote thing not working Actually...If you read back far enough, you'll find that he said what I said he said...ha...he was wrong at the moment, then came back after and said...Ok, I was wrong....he said compressing mass increases energy and mass...but it does not increase mass...and we all agree on that now...you just didn't see the original statement...forums can be confusing bits 1
Strange Posted January 6, 2015 Posted January 6, 2015 Are you saying that they have evidence of dark matter and dark energy that isn't associated with making general relativity work in regards to universal expansion? For dark matter, certainly. It is required by Newtonian gravity. Dark energy is explicitly related to expansion (and hence GR). I do believe I have a model that does away with the need for dark energy and dark matter... Then you need to show the maths of the model and show that it matches observation. That is how science works.
Robittybob1 Posted January 6, 2015 Posted January 6, 2015 (edited) Yeah over tired lol Due to gravity this question is trickier to answer. Mathematically the Lorentz transformation is a rotational matrix. So in essence a higher gravity potential implies more space time in a given region. One could use the analogy compressed spacetime however you have to include the rotational influence of the lorentz group rotational coordinates See page 12. http://www.google.ca/url?sa=t&source=web&cd=2&cad=rja&uact=8&ved=0CCAQFjAB&url=http%3A%2F%2Farxiv.org%2Fpdf%2Fgr-qc%2F9712019&ei=oJGrVOXeAYu6yQSD1ICgAw&usg=AFQjCNEir7fILQNyr5SGe-kxXg0mVlV5Vw&sig2=0SIbKSnNB35G_05CkQjMsA Due to the Lorentz rotation its probably more accurate to say light has a longer path to follow Keep in mind relativity isn't my strongest subject. Light takes a longer path because of gravity or spacetime is warped so the shortest path is now a curved one (geodesic). So can it be turned around with mass causing time dilation zones and mass moving toward time dilated regions so mass and light takes a curved straight path producing the effects of gravity. In other words gravity becomes the emergent property of mass compressing/dilating time. That was the first time I tried to write that sentence. just a thought that has been developing. Edited January 6, 2015 by Robittybob1
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 How can you say GR works well, when to figure galactic motion you have to pretend that there's more material missing than you can detect? Einstein didn't base his equations on mass that he couldn't account for...he based his equations on mass he could account for...Who makes an equation that doesn't work with the amount of mass that you can detect? GR works great in solar systems without any need for dark energy or matter...but then on this much larger scale where gravitational influences become less clear, it does not work.I believe his cosmological constant could have been more true than we give it credit for after hubble's discovery about accelerated expanding spacetime...I believe the cosmological constant may make a come back...of course, it would represent the amount of energy it takes to keep spacetime inflated at all...my foam needs a source of it's semi rigid nature...I say, it's energy we have not considered yet... Light can take a longer or shorter path due to gravity and sometimes it does it both at the same time...gravitational lensing can produce 2 or more images of the same star...the only path is a curved line...nothing about space time is straight at any moment...its all curves...although is may get pretty darn straight in long expanses of matter-less space-time..
ajb Posted January 6, 2015 Posted January 6, 2015 Well now that you mention it... GR is a geometric theory of gravity, and you're right, EM force isn't geometric. Electromagnetism is geometric. General relativity you should really be thinking in terms of the tangent bundle of space-time, or better the frame bundle. Connections and curvature are really always to do with bundles. In electromagnetism we have very similar geometric ingredients but the bundle is not the frame bundle but a principal U(1) bundle. But we don't talk about electromagnetic fields warping space-time. But people do. Look up the Einstein–Maxwell equations.
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 Being the frame bundle makes a really big difference though, doesn't it? EM definitely works on a geometrical basis...I only stated that EM is not said to warp spacetime geometry, rather only EMF geometry
ajb Posted January 6, 2015 Posted January 6, 2015 IF all anyone can tell me is "go read an introductory book on general relativity" or "learn the math" then there must not be anything left to say. If you toy with only what is known and proven about anything, when could you ever create a theory? After understanding what is well-known and understanding the real problems in physics.
Strange Posted January 6, 2015 Posted January 6, 2015 How can you say GR works well, when to figure galactic motion you have to pretend that there's more material missing than you can detect? That has nothing to do with GR. As I say, there are attempts to explain the observed behaviour by modifying the laws of gravity (look up MOND and its relativistic derivatives) but they don't work. Part of the problem is that it is hard to come up with a general model of gravity that models the distribution of dark matter in galaxies. But assuming it is matter, makes it easy. Also, there are other forms of evidence for dark matter which make it pretty certain that it is some form of matter. GR works great in solar systems without any need for dark energy or matter...but then on this much larger scale where gravitational influences become less clear, it does not work. But then on larger scales still, it does work.
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 As far as I know, the biggest problem in physics is dark matter and dark energy
Strange Posted January 6, 2015 Posted January 6, 2015 As far as I know, the biggest problem in physics is dark matter and dark energy I would have thought that the unification of GR and QM was. But it probably depends on your interests.
ajb Posted January 6, 2015 Posted January 6, 2015 I only stated that EM is not said to warp spacetime geometry, rather only EMF geometry Maybe we both need to be more careful with our language... Electromagnetic fields can act as a source of gravity. In this respect they do warp space-time; i.e. lead to non-trivial curvature of space-time. You can either fix the EM field and look at the resulting space-time geometry or study the full classical dynamics as governed by the Einstein-Maxwell equations.
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 To me, it doesn't really "work" if you have to create something which isn't proven, to make it work...IF they had clear evidence for dark matter and energy, we couldn't even have this conversation...
ajb Posted January 6, 2015 Posted January 6, 2015 (edited) As far as I know, the biggest problem in physics is dark matter and dark energy I would have thought that the unification of GR and QM was. But it probably depends on your interests. It depends on what you call big problems. By numbers of people working on those topics, it is not so important. But from a fundamental understanding they are. Edited January 6, 2015 by ajb
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 Electromagnetic fields can act as a source of gravity because they contain energy..but the impetus of the geometrical dances of EM are not related to spacetime geometry...rather the geometry of the EMF...
Strange Posted January 6, 2015 Posted January 6, 2015 IF they had clear evidence for dark matter and energy, we couldn't even have this conversation... They do. Do you think people just made these things up for no reason? Sheesh.
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 They made up dark matter and energy because the equations don't work without them....sheesh!
Strange Posted January 6, 2015 Posted January 6, 2015 They made up dark matter and energy because the equations don't work without them....sheesh! The equations work perfectly well. That is why they know that extra matter is required in galaxies to explain rotational speeds. Unless you are claiming that Newtonian gravity is wrong too. In which case you need to present an alternative model and show that it provides a better explanation. No one has been able to do that yet, so good luck. And then you need to explain all the other evidence for dark matter - presumably with a number of independent ad-hoc assumptions.
ajb Posted January 6, 2015 Posted January 6, 2015 They made up dark matter and energy because the equations don't work without them....sheesh! That is oversimplifying it. The equations do work very well in many situations and so people are generally reluctant to re-write gravity from scratch. Of course, this has been done and the most famous example here is MOdified Newtonian Dynamics. MOND is known not to be able to describe cosmology. The other route to fixing the galactic rotation curves is dark matter. This is at least compatible with cosmology via the lambda CDM model. I see no reason why one should not try to find some modified version of gravity that could take care of dark matter and still sit well with cosmology. The standard is high here as general relativity via the lambda CDM model seems to be able to describe our universe quite well. Anyway, some analogies with 'Einstein's trampoline' and 'compression of gluon fields' is far from enough. With that, are you able to show us your theory? Does it reduce to general relativity in some limits? Is it compatible with observational cosmology?
swansont Posted January 6, 2015 Posted January 6, 2015 Ya...the math itself is like a different dimension of understanding this stuff...I just know results of tests and experiments and what others have proved...But it does seem that the guys who dream stuff up are not always the ones who also prove that it's true. And even though Einstein had some outrageous math in quantum mechanics that could be explained to others, did anyone know he was right until experimentation proved it? Indeed. Models require experimental confirmation. But you need an actual model, i.e. the equations which allow for specific predictions, and then you can devise experiments that can confirm or falsify the idea. Einstein, for example, predicted the deviation of light by a massive body which was different from Newtonian physics and famously confirmed by Eddington. What kind of experiments would test your idea? Also, have a peek at the guidelines for posting in speculations
JohnSSM Posted January 6, 2015 Author Posted January 6, 2015 Nice comments and questions folks...I did just peruse the speculations rules...being brainfried, im gonna sleep on it...
Phi for All Posted January 6, 2015 Posted January 6, 2015 To me, it doesn't really "work" if you have to create something which isn't proven, to make it work...IF they had clear evidence for dark matter and energy, we couldn't even have this conversation... I think this statement is at the root of the problems you're having communicating your concept. You've somehow gotten the idea that dark matter was "created" only so some equations would work. You're also falling into the trap of thinking science tries to "prove" anything. Proof is for maths, science looks for supportive evidence of the best explanations. A lot of evidence can be gathered from what happens around a phenomenon. If I suspect I have cockroaches in my house but never see them (dark cockroaches?), I can spread some flour on the floor so I can see the tracks they leave. Clear evidence that I have cockroaches, but I've never "proven" it, nor have I seen a single roach.
Strange Posted January 6, 2015 Posted January 6, 2015 (edited) Also, the detection of "unseen" entities by the effect they have on other things has a long history and is not that surprising. A notable example is Neptune (which I have seen referred to as "the original dark matter") which "was mathematically predicted before it was directly observed" (1). So Neptune was made up because the equations don't work without it. It took 65 years from the original suggestion befoire Neptune was identified. A similar story with neutrinos. Conservation laws led to the suggestion that there were unseen particles. It, again took a few decades to detect these. Implausibly, they could travel through several light years of lead without any effect. Obviously such ridiculous particles can't exist. (1) http://en.wikipedia.org/wiki/Discovery_of_Neptune Edited January 6, 2015 by Strange 3
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