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Thread: Please rebut the Janus Cosmological Model

  1. #1
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    Question Please rebut the Janus Cosmological Model

    ***Preface***
    I'm new. Been lurking for a bit. I was pleasantly surprised at the civility/intelligence of this forum, even in ATM threads, so I decided to give it a shot. The model presented here isn’t mine, I simply discovered it through an odd series of clicks (much like cosmoquest actually). There is a good bit published on the topic, in peer reviewed journals (http://www.jp-petit.org/papers/cosmo), two educational comics (http://www.savoir-sans-frontieres.co...than_light.pdf http://www.savoir-sans-frontieres.co...n_universe.pdf), a website http://www.januscosmologicalmodel.com and a 20-something part series of youtube lectures in french with English subtitles (https://www.youtube.com/watch?v=kYIu...LaK0-2_A_TQrKB). Still, from what I’ve seen the model hasn’t gotten any traction in the mainstream scientific community due to the creator (Jean-Pierre Petit) having advocated quite strongly for some less-than-scientific ideas regarding extraterrestrials (specifically Ummites). As I am not able to find major problems with the model itself, I have been seeking out individuals more intelligent (or at least more astronomically literate) who might find and falsify what I couldn’t. After all, I wanna make Popper proud.

    JCM is a bimetric conception of gravity based on two coupled field equations which take into account both positive and negative masses. It’s the only sensible way I’ve heard negative masses and negative energies talked about, but including those ideas at all puts you firmly against the mainstream. The negative mass it claims to deal with is already present and we can observe its effects, we just haven't explained it as negative mass yet. This shift in perspective, according to Petit, solves or makes irrelevant at least a dozen major cosmological issues including but not limited to: the nature of dark matter/energy, the isotropy of the CMB, the missing baryonic matter, the behavior of the early universe (an alternative to inflation), an explanation for what happens to matter that enters a black hole, etc.

    Obviously I’m skeptical.

    Though, to his credit, all of these appear to follow directly from Petite’s bimetric conception of the universe (and his idea of a variable speed of light as a joint variation of all physical constants following a universal gauge relationship). He doesn’t need to appeal to anything except observational data, his model, and a bunch of crazy maths I can barely follow. But then again... I can barely follow it.

    ***Foundation***
    This is synthesized from a bunch of places, but it's a lot of copypasta- I hope that's okay.

    The precedent for negative mass begins with the Poincarė group and David Hilbert. In quantum field theory, the T operator acting on Hilbert spaces is complex, and can be either linear and unitary, or anti-linear and anti-unitary; but is arbitrarily chosen anti-linear and anti-unitary in order to prevent inversion of energy, as the vacuum state of the zero-point energy must have the lowest possible ground state and can not have negative values. However, when this axiom was formulated the accelerating expansion of the universe, which implies a negative pressure (pressure being understood as a volumetric energy density), had not been recorded, therefore it seems sensible to reconsider how we view negative energy states.

    According to Jean-Marie Soureau’s dynamical group theory, the action of elements of this group on movements in space-time result in some movements which follow a time reversal; they appear to be going "backwards through time". Modern physicists use the restricted Poincarė group, limited to only orthochronous movements, and therefore ignore this issue. In group theory, however, the T operator is real and we can explore retrochronic movements. Smarter people than I have shown, (http://ayuba.fr/souriau/Souriau-time...-inversion.pdf) using maths I can only begin to understand, that when using the full Poincare group time reversal goes with mass and energy inversion. So at least the precedent for negative mass is there, determined mathematically by an independent researcher.

    I’ve developed an illustrative way to explain this concept of negative mass in a bimetric universe using the classic rubber sheet example that Sagan and others have adopted over the years, but given the character constrains I'll leave it. You're all smart, you'll get it.

    So if we want to consider the universe this way we need two metrics, g(+)µν and g(−)µν, from which two different families of geodesics are calculated, referring to positive mass particles and negative mass particles respectively. From these metrics, we calculate Ricci tensors R (+) µν and R (−) µν as well as Ricci scalars R(+) and R(−) .

    Personally, I prefer to refer to "negative mass" as "inverted mass" simply because, the way that this model requires you to look at it, negative mass is not an intrinsic feature of some exotic matter, but instead stems from topological consequences; it is purely relative. The "bigravity" associated with inverted masses is an extension of general relativity describing the universe as a Riemannian manifold associated to two conjugated metrics generating their own geodesics, solutions of two coupled Einstein field equations:

    where χ is Einstein's constant

    Notice that if there is very little negative mass, the negative energy-tensor, T(-)µν, approaches zero and the upper equation for space-time according to the positive metric gets closer to Einstein's original field equation with a cosmological constant of zero. Thus we see that the two coupled field equations reduce to the Einstein field equations of general relativity for regions of space-time where positive mass largely dominates. Therefore this model automatically fits with local relativistic observations and measurements without any ad hoc changes in the same way GR reduces to Newtonian mechanics with small gravitational potential and at low velocities relative to c.
    I can't go through the proofs for the field equations here, but there are Lagrangian Derivations (https://www.researchgate.net/publica...ological_model) as well as the original formulation (http://www.jp-petit.org/papers/cosmo...voCimentoB.pdf) for the extremely invested.

    You may be asking about the bottom equation for space-time according to the negative metric. Wouldn't this mean the same material can be forced to follow two different equations of motion? No, the second equation gives the metric and spatial curvature for the "negative sector" of the manifold. This is the equivalent to being on the balloon side of the sheet. Positive mass (marbles), viewed from the underside of the sheet, will produce a negative curvature and an anti-gravitational effect. The system of two coupled field equations involves a 4D hypersurface with two sides, each type of mass belonging to its own metric. What is important to note however, is that the two field equations are coupled, i.e. a mass always creates a positive curvature in space-time according to its own metric (where the mass appears visible), and it also always induces a negative curvature in the conjugate metric (where the mass appears invisible). To reiterate, "negative mass" is not an intrinsic feature of some exotic matter. According to an observer measuring any mass in the same sector where it lays, that mass always appears positive. Fundamentally, a mass is not "positive" or "negative"; it is both. Its sign depends on from "which side" we are measuring that mass. It is therefore a purely relative concept.

    There’s a lot to unpack, and it makes sense to talk about the observational evidence for negative masses, but there's a character limit so I may not do it justice. The 1995 paper goes far deeper into this.

    ***Evidence***


    Consider the three boxes above. Current cosmological models insist there's far more dark matter than regular matter. If visible matter takes the pattern of the far left box, we can assume there is more inverted mass in the area. If visible matter takes the pattern of the middle box, we can assume there is more regular mass in the area. For reference, and to illustrate the reality, the far right box has been included. This would be the full distribution of all matter on both sides of the manifold, assuming there is a large difference in how much mass/energy is present in either sector.


    Standard models of the universe describe large galaxy clusters linked by hundred-lightyear long threads of galaxies surrounding massive empty voids. This can be pictured like bubbles from a pot full of dish soap. Planes of soap would be fairly rarified areas of matter, lines would be the galactic threads, and vertices of the bubbles would be galactic clusters. The ΛCDM model proposes "galactic filaments" which accrete around threads of dark matter that I have yet to see anyone convincingly locate.
    When we look at the universe on a grand scale, it seems to imply there is a greater distribution of inverted masses due to the filamentous shape (like the left box). But if we deign to zoom in on a section of the universe, say our solar system or galaxy, we find something like the middle box. What this implies is that the third box describes reality at both the grandest and more local cosmic scales- but at some point they switch. So on the universal scale the dark clusters are inverted mass matter pushing regular matter into filaments, but on more local scales we consider the dark clusters galaxies held in rotation by the inverted matter surrounding them. The fuss made by Dr. Farnes’s negative-mass fluid (which I’m sure took this place by storm) does a similar, but less ontologically justified, thing by nestling galaxies in a field of repulsive material.

    "Ah, Okay," I can almost hear you mutter, "but what about gravitational lensing?”

    This illustration shows the effects of negative and positive lensing. You can mimic it at home with two paper circles, a pair of scissors and some tape if you have them.

    This negative curving would, in the presence of a large hole empty of any matter, give a focalization effect. This focalization would be reinforced by a positive mass in the center of that empty space, accounting for the massive discrepancy between apparent matter and matter required for strong [positive] gravitational lensing. An illustration follows:

    In the JCM, there is no cosmological constant because it’s unnecessary. The math is well beyond me (found https://januscosmologicalmodel.com/p...ysSpaceSci.pdf in section 6, non-steady state solution for dust universe). It seems the identity of matter/energy in the negative sector is sufficient to calculate the deceleration parameter, which Petit gives as −0.087 ± 0.015. The JCM can calculate this due to precise knowledge of what comprises dark matter, which is determined using group theory. A recently published peer-reviewed article (http://www.jp-petit.org/papers/cosmo...ysSpaceSci.pdf) shows how the Janus Cosmological Model is compatible with modern observational data.

    There's a lot more, but let's start here.
    Last edited by Shadowybeige; 2019-Aug-03 at 02:29 AM.

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    Shadowybeige

    Welcome to CQ. Glad you think we are civil.

    The Against The Mainstream (ATM) forum is for advocating a non-mainstream idea, either your own or someone else's. It is not clear to me whether you are just asking about the JCM model, or you are advocating its "truth". Please make your intentions clear in your next post. If you are advocating, the ATM forum is the perfect place for it. If you are just asking questions about, are not advocating it, and are willing to accept the mainstream answers to it, we'll move the thread to the Q&A forum.

    If you are in between those two positions, (neither defending the JCM model, nor accepting the mainstream), then we will have to close this thread, as we expect people to defend the ideas in the ATM forum; it is not for an unstructured discussion.
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    Thanks! I'm not necessarily advocating for this model, but I would like to try and defend it against critiques from the CQ community.

    Just so my biases are clear, I’m pretty thoroughly convinced that even if the model isn’t correct per se, it definitely feels like the next proper step in cosmology, akin to the copernican heliocentric model before Keppler revised it to include elliptical orbits. Personally I much prefer a geometric/topological consideration which explains the evidence rather than “invisible stuff we don’t know the nature of”. That said, I studied philosophy of science, not physics, and I kept my fieldwork to the less mathy bits. So I’m grossly out of my element when it comes to tensor equations or dynamical group theory, and I recognize that fully. Epistemologically and ontologically the model seems to check out, but if the math is wrong, the math is wrong. I’ve spent somewhere in the ballpark of 45-60 hours just learning the background to understand the model so hopefully I can defend it adequately. If I can’t answer your question myself, I may be able to point to the bit of math where Petit claims to answer it. Despite my being mathematically handicapped, I think I’m up to the task.

    I’m not necessarily trying to convince anyone though; I just want to put the JCM through rigorous review because I alone am incapable of determining the model's strength, esp grander cosmological models like this. I know this post is long and the rules say to keep it short, but I tried to be extra clear and maybe even a little repetitive because the ideas can be so convoluted.

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    I guess the short answer is pretend I'm advocating for it and I'll pretend I know enough to defend it.

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    Quote Originally Posted by Shadowybeige View Post
    I guess the short answer is pretend I'm advocating for it and I'll pretend I know enough to defend it.


    That will go perfectly with me pretending to be a moderator and pretending to know what the heck all of you are talking about.
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    Shadowy:

    My first initial response to this is how does it explain things like the Bullet Cluster? https://en.wikipedia.org/wiki/Bullet_Cluster The Bullet Cluster has 2 galaxies colliding in which the stars passed through without interacting since there is so much empty space between stars, but the interstellar gas in the galaxies collided and so didn't make it out the other side. This has the effect of separating the galaxy into 2 masses, one of the stars and a different one of the gas. But when we map out the dark matter we find that all of it passed out the other side, meaning it didn't interact with itself. So whatever dark matter is, it can't be interstellar gas thats just in some other dimension so we can't see it.

    So, if the JCM predicts that dark matter is just ordinary matter that we can't see, then this would see to contradict it as the Bullet Cluster and things like it are evidence that dark matter behaves very differently from ordinary matter in that it apparently can't interact with itself. Do you know what the JCM has to say about this? Thanks.

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    Oh! I remember seeing a neat video about that! It's a really good point, I even remember at the time being pretty confused about it.

    Just to be clear, I think you're talking about this part of the Wiki article (because if you're not the rest of this might be barking up the wrong tree):
    "In theories without dark matter, such as Modified Newtonian Dynamics (MOND), the lensing would be expected to follow the baryonic matter; i.e. the X-ray gas. However, the lensing is strongest in two separated regions near (possibly coincident with) the visible galaxies. This provides support for the idea that most of the mass in the cluster pair is in the form of two regions of dark matter, which bypassed the gas regions during the collision. This accords with predictions of dark matter as only weakly interacting, other than via the gravitational force."

    The conclusion I came to is that the ΛCDM-model is looking for dark matter with positive mass and some other property which renders it invisible, since that is the only way these phenomena can be interpreted under that model; the JCM would be looking for inverted mass, which would display a repulsive effect (and therefore you would expect not to find it with most of the visible baryonic mass, but rather nestled between the largest gaps of baryonic mass). The best example I can give which displays a similar misunderstanding, is when people respond that dark matter is not out in the intergalactic voids of space, but in filaments holding galaxies in place. That would be positive mass dark matter which can only attract. Repulsive inverted matter repels. Again, the stuff where they explain how gravitational lensing is measured under the JCM (http://www.jp-petit.org/papers/cosmo...the-matter.pdf specifically section 7- gravtiational lensing due to negative mass matter) is mathematically beyond me but I encourage those who can read it to do so and report back.

    Since it's a new post and the example is relevant I'll show my one idea for this system which isn't copypasta (although I guess it is now);
    It's just a neat way to explain this concept of negative mass using the classic rubber sheet example to explain general relativity. I think it's particularly fitting because the JCM is supposed to be to GR as this example is to the original:

    The analogy is of space-time to a sheet, and when masses like bowling balls are introduced the sheet warps to create curvature. A marble shot in a straight line past a bowling ball on this sheet would follow an apparently curved path, a geodesic. According to most models, negative masses follow the same geodesics as positive masses since there is only one metric tensor. However, unlike the positive-mass bowling balls, negative masses induce a negative curvature, which gives rise to an "anti-gravitational" effect. So the negative-mass-marbles would slide along the sheet, but "pull" the sheet up towards them as they move. This poses obvious problems when they begin rolling towards a bowling ball. Even though the marble induces negative curvature, it is still affected by the positive curvature of the sheet around the bowling ball. Because the sheet is continually pulled towards the marble as it rolls down the hill towards the bowling ball, and the bowling ball is pushed by the sheet being pulled towards the marble, the warped state of space stays constant and the motion continues perpetually. This was addressed by Hermann Bondi, and is commonly known as "runaway motion". This definitely violates both intuition and physics.

    Let's change the situation slightly; think about how we might get the same anti-gravitational effect without invoking strange counter-intuitive "negative mass marbles". Perhaps we could use similarly sized spherical balloons filled with various lifting gasses to represent different negative masses of different densities? Immediately we can see the behavior is not so strange as long at the marbles and balloons are on opposite sides of the sheet. Then it becomes intuitive that the balloons, who want to ascend, will push away the marbles, who want to descend, as they both respectively warp the sheet. We can see that the balloons will aggregate as they all "fall" up towards the steepest hill, and marbles will aggregate as they fall into the deepest wells. In essence, like attracts like and opposites repel. If we place a marble and balloon in the same spot we can watch them roll away from each other. And because they are on opposite sides of the sheet, they can roll right past each other as they attempt to find their spot, but cannot collide or interact at all except by warping the sheet (ie gravitationally). In order to get something that works like this though, the marbles and balloons must be on opposite sides, ie following different geodesics. It's because they follow different geodesics that they cannot interact except gravitationally; the principle is a geometric one, not a physical one.

    In relation to the bullet cluster example, I imagine a batch of marbles and balloons mingled together being smashed with a bunch of other marbles and balloons. Then to me it seems pretty reasonable that the sandy/pellet/ballbearing sized stuff kinda just forms a pile and the more massive bowling ball sized stuff just smashes through on either side of the sheet. My crude 2-dimensional analogy is merely used to explain things, but it does help illustrate what may be happening in our very own 4-dimensional universe.

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    Also on that point, gravitational lensing is what makes JCM falsifiable. In the linked video, around 14min mark, Petit gives a simplified version of how dark matter is mapped with weak gravitational lensing and then claims that with negative mass the distortion is read differently. This means that if we map out dark matter via weak gravitational lensing tracking a radial distortion pattern we should find most of it in the intergalactic voids of space. If not, the JCM would be a less viable option. Ironic, I suppose, that the possibility of being wrong is a point in its favor.

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    Thanks for that. While that was certainly informative and helps me understand the idea better, I don't think it addressed the main point I was asking about. Regardless of how the "positive vs negative" masses will interact (it can give one a headache trying to keep it straight, right?), what we see from mapping the dark matter is that whatever it is, it didn't separate into 2 masses when it collided with itself like our matter did. In our universe, matter is in both very dense states (stars) and very diffuse states (interstellar gas). And those interact differently, thus when our galaxies collide the result is 2 separate masses. However dark matter does not do this, everything behaves like our dense matter states.

    So if we stick with the idea of negative masses on the other side of the rubber sheet, that tells me that unlike our universe either all dark matter is in a collapsed, dense state or that it does not interact with itself like interstellar gas does. Either way, it's very different from the matter we see around us and so whatever it would be on the other side of the sheet, it can't be made up of standard model particles.

    So if the JCM requires a unique form of matter to exist, I don't see how it has any advantage over the CDM model which also requires a unique form of matter to exist. The JCM just adds another complication that in addition to dark matter being a unique form of matter, it also resides in a hidden dimension AND has negative mass.


    Something else to clear up that just occurred to me: For the negative masses on the other side of the "sheet" they will repel each other, correct? And from our side because the topology gets inverted we still see it as an attractive force. Assuming that is correct, then I would expect most of the dark matter to never clump together to form dense objects at all, and so that would make the other side of the rubber sheet a mostly uniform field of negative mass. That means that dark matter, even in the JCM still has the property that it can't interact electromagnetically or with itself because otherwise when the Bullet Cluster collided the dark matter would have all stayed together where the interstellar gas ended up.

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    Quote Originally Posted by Dave241 View Post
    Thanks for that. While that was certainly informative and helps me understand the idea better, I don't think it addressed the main point I was asking about. Regardless of how the "positive vs negative" masses will interact (it can give one a headache trying to keep it straight, right?), what we see from mapping the dark matter is that whatever it is, it didn't separate into 2 masses when it collided with itself like our matter did.
    The main point that I tried to make (maybe not clearly enough) is that the WAY JCM maps inverted mass matter is different from the way dark matter is mapped. The weak gravitational lensing (which is the observed evidence to be explained) was mapped according to the concordance model, which is why we think it's dark matter, and why we think it is where it is. If we map the lensing according to the JCM, we should find the "dark matter" (in this model negative mass matter) in a wholly different location. Ideally that location would be nestled within the largest gaps between visible baryonic matter.

    Quote Originally Posted by Dave241 View Post
    For the negative masses on the other side of the "sheet" they will repel each other, correct? And from our side because the topology gets inverted we still see it as an attractive force.
    Quote Originally Posted by Shadowybeige View Post
    What is important to note however, is that the two field equations are coupled, i.e. a mass always creates a positive curvature in space-time according to its own metric (where the mass appears visible), and it also always induces a negative curvature in the conjugate metric (where the mass appears invisible).
    So, essentially, no. That's not correct.
    Unfortunately, this means my metaphor wasn't good enough Or maybe I got carried away and the core got lost:
    "the balloons, who want to ascend, will push away the marbles, who want to descend, as they both respectively warp the sheet. We can see that the balloons will aggregate as they all "fall" up towards the steepest hill, and marbles will aggregate as they fall into the deepest wells. In essence, like attracts like and opposites repel"

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    Quote Originally Posted by Shadowybeige View Post
    The model presented here isn’t mine, I simply discovered it through an odd series of clicks (much like cosmoquest actually). There is a good bit published on the topic, in peer reviewed journals ...
    This is Jean-Pierre Petit who is a retired plasma physicist who has been working on his Janus cosmological model since 1977. This is a model that is still "highly speculative" after 42 years!

    What makes a model better than others is not the ability to replicate their results but the ability to make testable predictions that distinguish the model from others and are found to be correct. If GR only duplicated Newtonian gravity it would be discarded. GR is the better fit to existing data (the orbit of Mercury) and the phenomena unique to GR (gravitational time dilation, gravitational lensing, black holes, etc.). That makes GR the outstanding theory of gravitation and cosmology.

    The rebuttal is the question: What are the predictions of the model that are unique to the model and what is the evidence supporting them? I have seen none in the thread so far.

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    Quote Originally Posted by Dave241 View Post
    My first initial response to this is how does it explain things like the Bullet Cluster? https://en.wikipedia.org/wiki/Bullet_Cluster The Bullet Cluster has 2 galaxies ....
    Small correction, Dave241, the Bullet Cluster is 2 galaxy clusters colliding. Galaxies and stars are not greatly affected by the collision. We see the collision of the gases in the clusters as x-rays from shock waves. All of the matter is then mapped using gravitational lensing and there is a lot of matter that is separate form the normal matter. That dark matter has passed through the normal matter without interacting.

    This may invalidate JCM because it has seems to have negative matter that does interact with positive matter. If the clusters had mixed negative and positive matter, no dark matter would be detected.

    ETA: Shadowybeige, we do not just map out dark matter with gravitational lensing - we map out all matter. The point of the Bullet Cluster and several other observations is the separation of dark matter from normal matter as expected from a form of matter that does not interact much with normal matter.

    Another line of evidence for dark matter that JCM has to explain is the CMBR and its power spectrum.
    Last edited by Reality Check; 2019-Aug-05 at 01:50 AM.

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    Quote Originally Posted by Dave241 View Post
    I don't think it addressed the main point I was asking about. Regardless of how the "positive vs negative" masses will interact (it can give one a headache trying to keep it straight, right?), what we see from mapping the dark matter is that whatever it is, it didn't separate into 2 masses when it collided with itself like our matter did.

    ...

    Something else to clear up that just occurred to me: For the negative masses on the other side of the "sheet" they will repel each other, correct?
    To the first bit, I emphasize my previous point:
    Quote Originally Posted by Shadowybeige View Post
    The conclusion I came to is that the ΛCDM-model is looking for dark matter with positive mass and some other property which renders it invisible, since that is the only way these phenomena can be interpreted under that model; the JCM would be looking for inverted mass, which would display a repulsive effect.
    The point here is that how dark matter is mapped will differ between the two models, so where it is will also differ. As to the second point, I emphasize my little metaphor to keep things straight. (and I don't blame you for missing this, I hit you with a wall of text.)
    Quote Originally Posted by Shadowybeige View Post
    the balloons will gather as they all "fall" up towards the steepest hill, and marbles will gather as they fall into the deepest wells. In essence, like attracts like and opposites repel.
    Realitycheck may have a harder problem for the model which I should address in a separate post.

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    Quote Originally Posted by Reality Check View Post
    The rebuttal is the question: What are the predictions of the model that are unique to the model and what is the evidence supporting them? I have seen none in the thread so far.
    Quote Originally Posted by Reality Check View Post
    This may invalidate JCM because it has seems to have negative matter that does interact with positive matter. If the clusters had mixed negative and positive matter, no dark matter would be detected.
    This may be true, but I'm not sure if I understand you fully. Negative and positive masses do interact, but only through gravitation. So if there were a lab with the proper instruments (which there are) who were willing to indulge JPP (not so much), they could modify the code to map dark matter according to the JCM (a simplified version of which is identified in the above post about falsification). That seems like it is a unique prediction, which the observational evidence intuitively supports according to maps of visible matter under the ΛCDM-model (see quote)
    Quote Originally Posted by Shadowybeige View Post

    Standard models of the universe describe large galaxy clusters linked by hundred-lightyear long threads of galaxies surrounding massive empty voids. This can be pictured like bubbles from a pot full of dish soap. Planes of soap would be fairly rarified areas of matter, lines would be the galactic threads, and vertices of the bubbles would be galactic clusters. The ΛCDM model proposes "galactic filaments" which accrete around threads of dark matter...
    I understand if you don't like that one, but what about the dipole repeller? I know that is a favorite of Petit's. I haven't kept up with explanations for the phenomenon though. Last I heard the math was under dispute. You could say that the JCM posits a large conglomeration of negative mass matter there which implies a whole series of predictions about movement of visible celestial bodies away from it (and only away from it). Not to mention, combined with the imaginary instance above, we'd be able to map supposed negative mass matter as it was attracted to and flowed towards the "supervoid". I don't know how strong the evidence is because I can't interact with the actual data, but it should be possible to find out the correlation between the model's predicted movements and measured movements.

    That hardly seems any more speculative than the ΛCDM-model to me, but you might be using the word differently than I am.

    As far as that last part "If the clusters had mixed negative and positive matter, no dark matter would be detected. I get the impression that there is supposed to be negative mass matter, at least in some rarefied form- stray photons maybe, basically everywhere there isn't enough positive mass to gravitationally eject it. So in clusters (and even within galaxies I believe) there would be indeed a large collective amounts of negative mass and it would be detected as dark matter under the ΛCDM-model. Then again, the presence of diffuse galaxies would imply (under the JCM) that the distribution of negative mass/energy, while consistent, is not entirely uniform.

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    Quote Originally Posted by Shadowybeige View Post
    Again, the stuff where they explain how gravitational lensing is measured under the JCM (http://www.jp-petit.org/papers/cosmo...the-matter.pdf specifically section 7- gravtiational lensing due to negative mass matter) is mathematically beyond me but I encourage those who can read it to do so and report back.
    The problem with the conference presentation is not the math but the English - or at least the translation for French. This is a conference in 2001.
    • Galactic dynamics are not a "empty box" - they are a well established and ongoing field of research.
    • A "theoreticians reactivate the so-called cosmological constant" assertion is not right. GR does have a cosmological constant. The simplest explanation for the observed acceleration of the expansion of the universe is a non-zero cosmological constant.
    • "nobody knows how a galaxy works and forms" is wrong.
    • Correct - the search for MACHOs as an explanation for dark matter has failed.
    • What looks like a "120 free parameters" mistake (may be the 19 free parameters in the Standard Model).
    • Finding puzzling concentrations of dark matter does not make dark matter vanish.

    Later on there are rather silly statements like "Today, theoreticians spray ad hoc distributions of unidentified dark matter, in order to fit gas rotation curves, that's all." when the presentation has *Fig 5 "Ad hoc twin matter distribution, ...".

    "8- Exotic matter or exotic geometry?" Missing antimatter in the universe is not "so embarrassing that today scientists just choose to avoid it." - scientists have been working on the issue since it was found. We get the exotic matter and geometry but no explanation of the missing antimatter! The explanation is not vanishing into a "twin universe", it is additions to the known mechanisms that create matter over antimatter. Their idea is that the antimatter somehow vanishes into the other fold in their metric as if that were a "twin universe".

    "- By the way: what's a graviton?" is strange question.

    A strange leaking neutron star model that "challenges black hole model, whose validity is contested on theoretical grounds." That is just wrong. Black holes are a textbook result of GR. Assertions about "too few candidates" I and what "everyone knows" in 2001 does not make those candidates not black holes. "22- Black holes do not exist" is massively wrong today! But what they actually seem to do is invalidate their Janus cosmological model by showing that it cannot have black holes because of a "bridge" linking their 2 folds. That "bridge" does not exist in GR.

    ETA: A later 2015 paper does a similar thing. It makes the central singularity of a black hole go away by introducing a "bridge" to their other JCM fold.
    Last edited by Reality Check; 2019-Aug-05 at 03:41 AM.

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    More bits of doubt about JCM, Shadowybeige, are those "bridges" between folds.
    We know that similar "bridges" in GR (wormholes) are unstable. Why is the same not the case for JCM or do they just assume that the "bridges" have to be possible and stable?
    If natural wormholes existed then it is possible that we would see matter exiting them - they would be "white holes". How does JCM explain away the lack of evidence of "bridges" from the other fold?

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    Um, are my posts not coming through for some reason? Am I breaking formatting or something? Maybe I'll try no formatting. or busy mods.

    Essentially, I pointed to a very specific part of that article and referenced exclusively the math because I don't condone how snarky the translator (and I believe co-author) was. I agree as an academic you shouldn't make a strawman of the concordance model. And as a philosopher I doubly agree that the rest of the article is pretty bad. Especially the "what is a graviton?" The thing reeks of overconfidence. I hope I have not come across in that way. I ESPECIALLY wanted to stay away from the whole "FTL potential aliens" stuff although that deserves it's own CT thread one day.

    I probably can't answer that last point sufficiently. I specifically didn't bring it up because I couldn't address it confidently lol. I can deal with Dave241's points (but my posts quoting them are either not being looked at by busy moderators or being eaten by my browser). I would assume JPP probably has some theory about quasars. I mean, don't quote me because again this model is pretty much just a hobby for me, but if there were matter being ejected through black holes as negative mass (because that's the idea, I believe- mass goes in the "hole in the sheet" and comes out "the other side") then potentially a great enough amount would make a "splash". Again this is my BLIND or mostly-blind ASSUMPTION, but I imagine it like a bullet coming out of a water-balloon. The problem is, negative mass should repel the positive mass so I can't imagine the "splash pattern" as it were would be the same. It would also have to be a lot of matter getting ejected to push other matter out from the event horizon. It's a shot in the dark.

    As for how he explains the lack of negative-mass black holes, it has to do with what I mentioned in the first post about "his idea of a variable speed of light as a joint variation of all physical constants following a universal gauge relationship". If this post gets through, I'll write another more specific one, but for now I'll just say that according to JPP things are so different on the other side that stars take orders of magnitudes longer to light up- let alone die. So if we're correct about the age of the universe, and I'm correct about the JCM there would be billions if not trillions of years before a negative mass black hole would form. I'll try to find a source when I'm less sleepy.

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    http://www.jp-petit.org/papers/cosmo...in-Physics.pdf

    Here's the best explanation I can find about determining how things work on the negative side. WARNING it's a little snarky. Not as bad as the other one, but still too confident for my liking.

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    https://snag.gy/uEj3Vn.jpg

    So I couldn't find the paper where this concept is discussed more clearly in a peer-reviewed setting, but this clip from the Twin Universe comic linked in the OP gets the idea across. If the physics doesn't allow for fusion in negative mass "stars" I can't imagine they'd get big enough to collapse into a black hole. The idea that physics would act so differently in the negative sector is an admittedly unintuitive consequence from the notion that it's CPT symmetric. If I understand correctly, the equations of physics have to remain invariant but the individual constants can change according to this excerpt from the most recently quoted article:
    (note, there's a seemingly serious typo where it says [blank] and [blank] are space and time factors. I have no idea what that's supposed to say.)

    https://snag.gy/qGPNSL.jpg

    Quote Originally Posted by Reality Check View Post
    A strange leaking neutron star model that "challenges black hole model, whose validity is contested on theoretical grounds." That is just wrong. Black holes are a textbook result of GR. Assertions about "too few candidates" I and what "everyone knows" in 2001 does not make those candidates not black holes. "22- Black holes do not exist" is massively wrong today! But what they actually seem to do is invalidate their Janus cosmological model by showing that it cannot have black holes because of a "bridge" linking their 2 folds. That "bridge" does not exist in GR.

    ETA: A later 2015 paper does a similar thing. It makes the central singularity of a black hole go away by introducing a "bridge" to their other JCM fold.
    We definitely agree that Petit doesn't exactly find the most academic people to translate/promote his work. But to be fair, the scientific community has largely shunned him. Then again, to be fair, he was barking about aliens writing him letters. I just want to focus on the actual model and the math since I addressed in my first post that he's known for less than scientific ideas. I prefer to watch his videos. They're long and he likes to ramble, but he comes off far less cranky in person.

    As for the 2015 paper, I assume you're referring to this article titled "Cancellation of the central singularity of the Schwarzschild solution with natural mass inversion process". As far as I could tell this was an attempt to EXPLAIN what we call "black holes" as "bridges" WITHIN the framework of GR (since it's literally using the original 1916 Schwarzschild solution to derive the answer). In no way does this show that the JCM can't have black holes. JCM explicitly has black holes; it just also has an explanation for what black holes are, how they're formed, and what happens to mass once it reaches the would-be-singularity. What's more, it doesn't appeal to outside entities or assumptions beyond those proposed by math and the inherent geometric aspects of the model.

    In terms of Occam's razor, the JCM seems to posit fewer mysterious independent forces. I found this comparison on a french forum comparing the way the two models explain dark energy/matter, and I think it's a perfect example (I’ve edited the snarkiness down a bit as well):
    “According to the ΛCDM model, the vacuum is "empty" (from a matter point of view: there are almost no real particles in a hard vacuum) but is "non-empty" from an energy point of view. It has a positive energy state. Invisible dark matter (of positive mass) may be there in space, but has nothing to do with the accelerating cosmic expansion, unlike dark energy and its associated negative pressure driving the expansion process. Two different things. According to the Janus model, where the vacuum appears to be empty, it is also really not. this is not according to a quantum notion of an energy of the vacuum, but has all to do with the invisible presence of some [negative] mass. In our positive sector, the vacuum appears to be a rarefied medium full of photons with almost no mass particles. But in reality some mass, located in the negative sector, is "there" everywhere, especially in the voids of deep space, although being invisible. Such matter has a negative energy hence a negative mass. It interacts with positive mass matter in our positive sector through gravitation (challenging dark matter) and it also exerts a negative pressure (challenging dark energy) which drives the accelerating expansion of the universe.”

    Also, since it was in one of the posts that didn't come through: I want to emphasize the confusion regarding "dark matter" and its mapping. HOW the two systems map dark matter is different because of WHAT the two systems think dark matter is, therefore WHERE they conclude the actual material responsible for the gravitational warping is, will be different. The JCM maps negative mass matter using reverse or negative gravitational lensing while the Concordance model maps dark matter using positive gravitational lensing. This is because the JCM does not rule out negative masses a priori the way the ΛCDM model does; in fact, the ΛCDM model HAS to posit mysteriously invisible positive mass matter that is undetectable except through gravitation since positive is the only kind of mass.

    I hope that answers, or at least clarifies things.
    Last edited by PetersCreek; 2019-Aug-07 at 07:40 PM. Reason: Over-size images

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    Quote Originally Posted by Reality Check View Post
    Shadowybeige, we do not just map out dark matter with gravitational lensing - we map out all matter. The point of the Bullet Cluster and several other observations is the separation of dark matter from normal matter as expected from a form of matter that does not interact much with normal matter.

    Another line of evidence for dark matter that JCM has to explain is the CMBR and its power spectrum.
    I missed this. For the first point: see all the times I've mentioned problems using the location of dark matter as evidence for/against either model. The second point however is far more interesting and the main topic of the comic Faster Than Light (which is how i actually stumbled onto this whole mess). JCM does have an answer for at some odd observations regarding the CMBR, which end up leading to an interesting alternative to inflation. I know you won't read the comic, so see following images for a shallow treatment of the problem. Again, I edited out the snarkiest/crankiest bits, but if you can handle a little bit of sass the comics really are excellent. (Is there a way to shrink these down?):
    https://snag.gy/azW23c.jpg
    https://snag.gy/Qe7o9A.jpg
    https://snag.gy/3aXDKu.jpg
    https://snag.gy/Dmz2Gh.jpg
    https://snag.gy/5NamTV.jpg

    I will look for it, but there's a great graph which shows how the value of all the physical constants inevitably and asymptotically move towards their current values.
    Last edited by PetersCreek; 2019-Aug-07 at 07:41 PM. Reason: Over-size images

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    Quote Originally Posted by Shadowybeige View Post
    We definitely agree that Petit doesn't exactly find the most academic people to translate/promote his work. But to be fair, the scientific community has largely shunned him.
    Which is yet another reason why his idea is dubious. A invalid idea is usually ignored by scientists. He has been promoting his idea for 40 years so if it had any merit there would be a large body of published papers on it from a wide range of scientists.

    Quote Originally Posted by Shadowybeige View Post
    "Cancellation of the central singularity of the Schwarzschild solution with natural mass inversion process". As far as I could tell this was an attempt to EXPLAIN what we call "black holes" as "bridges" WITHIN the framework of GR...
    That is not what his paper is about. GR does not have his other fold. GR does not have arbitrary "bridges". GR has wormholes (or Einstein–Rosen bridges) which are not his "bridges".
    The paper is not an explanation of black holes - it is close to a fantasy about how to remove the central singularity of black holes that must exist in GR.

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    Quote Originally Posted by Shadowybeige View Post
    I missed this. For the first point: see all the times I've mentioned problems using the location of dark matter as evidence for/against either model.
    You have made no points about any problems using the location of dark matter as evidence for the Lambda-CDM model. The location of both dark and normal matter is detected by gravitational lensing - no problems there. The location of normal matter is detected by its radiation - no problems there. The physical separation of dark matter and normal matter shows that dark matter is not a modification of GR. That is a point of the Bullet Cluster paper - A direct empirical proof of the existence of dark matter
    We present new weak lensing observations of 1E0657-558 (z=0.296), a unique cluster merger, that enable a direct detection of dark matter, independent of assumptions regarding the nature of the gravitational force law. Due to the collision of two clusters, the dissipationless stellar component and the fluid-like X-ray emitting plasma are spatially segregated. By using both wide-field ground based images and HST/ACS images of the cluster cores, we create gravitational lensing maps which show that the gravitational potential does not trace the plasma distribution, the dominant baryonic mass component, but rather approximately traces the distribution of galaxies. An 8-sigma significance spatial offset of the center of the total mass from the center of the baryonic mass peaks cannot be explained with an alteration of the gravitational force law, and thus proves that the majority of the matter in the system is unseen.
    You mentioned that JCM is invalidated somehow by problems with gravitational lensing. I suspect that JCM is invalidated because it cannot match observations of gravitational lensing. Bending of light by the Sun? Einstein rings? The empirical evidence that dark matter is non-baryonic matter from colliding galaxy clusters?

    Comics are not science.

    No evidence that JCM can explain the CMBR and its power spectrum.
    Last edited by Reality Check; 2019-Aug-07 at 09:10 PM.

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    Quote Originally Posted by Shadowybeige View Post
    In terms of Occam's razor, the JCM seems to posit fewer mysterious independent forces.
    Occam's razor is that if we have 2 theories that give the same set of results, the theory that postulates the fewer entities is to be preferred. But JCM does not give the same set of results as the Lambda-CDM model. Even if JCM gave the same set of results, it is doubtful whether it has fewer entities. To explain stuff it seems to assign the other fold specific distributions of negative matter each of which could be considered an entity.

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    Quote Originally Posted by Reality Check View Post
    Which is yet another reason why his idea is dubious. A invalid idea is usually ignored by scientists. He has been promoting his idea for 40 years so if it had any merit there would be a large body of published papers on it from a wide range of scientists.
    That's just factually inaccurate. There are a million reasons (social, religious, economic, racial) why good ideas would get ignored. The history of science is full of these examples. In fact, how long after Copernicus before the heliocentric model was the mainstream?
    An invalid idea should be addressed and refuted by scientists, not ignored. Some ideas aren't worth refutation, I'll admit. But if you think that applies here, don't bother responding.

    Scientists that don't bother to actually discuss opposing ideas are half of why the populace is developing such a strong an anti-science sentiment. You could argue they're responsible for Flat-Earthers gaining so much traction. When people don't know how to independently verify the quality of an idea, they're at the mercy of any idea that sounds good whether it is or isn't. But that's not the point; my point is that how much literature has NOT been done on a subject says nothing CONCLUSIVE about the quality of the ideas. That's just a social intuition based on the idea that science is a meritocracy and good ideas float to the top. Rather, the scientific indication that an idea is worthless is a lot of literature either pointing to many different and mutually exclusive conclusions, or just straight refuting it through multiple falsifications. This is ESPECIALLY true in the age of the internet where literally hundreds of thousands of research papers go unread by more than a dozen people every year. I'm sure plenty of good science is ignored. Just because bad ideas are ignored doesn't mean good ideas can't be ignored.

    In other words, science doesn't get better because we a priori know which ideas are good and we pick them out of a hat. Science gets better because we continually and rigorously falsify everything that doesn't work, leaving only the theories and models that prove themselves to survive. No matter which of these two models you prefer, they're both wrong.


    Quote Originally Posted by Reality Check View Post
    Comics are not science.
    That's both irrelevant and highly disputable, but alright.


    Quote Originally Posted by Reality Check View Post
    Occam's razor is that if we have 2 theories that give the same set of results, the theory that postulates the fewer entities is to be preferred. But JCM does not give the same set of results as the Lambda-CDM model. Even if JCM gave the same set of results, it is doubtful whether it has fewer entities. To explain stuff it seems to assign the other fold specific distributions of negative matter each of which could be considered an entity.
    That's unfair and I suspect you know it. Newtonian mechanics doesn't posit an indefinite number of entities just because it posits mass and every celestial body we know about has mass. It's exactly as preposterous to assume every body of negative mass is a new postulated entity under the JCM.
    You didn't even address my actual point, namely that in JCM one entity which arises as a natural consequence of the model (negative mass) is sufficient to explain observations while ΛCDM requires at least two entities (dark matter/energy), which are posited without ontological basis and which work through unknown mechanisms, to explain the same set of observations. Occam's razor seems perfectly suited to this problem.


    Quote Originally Posted by Reality Check View Post
    You have made no points about any problems using the location of dark matter as evidence for the Lambda-CDM model. The location of both dark and normal matter is detected by gravitational lensing - no problems there.
    Quote Originally Posted by Shadowybeige View Post
    the ΛCDM-model is looking for dark matter with positive mass and some other property which renders it invisible, since that is the only way these phenomena can be interpreted under that model; the JCM would be looking for inverted mass, which would display a repulsive effect (and therefore you would expect not to find it with most of the visible baryonic mass, but rather nestled between the largest gaps of baryonic mass). The best example I can give which displays a similar misunderstanding, is when people respond that dark matter is not out in the intergalactic voids of space, but in filaments holding galaxies in place.
    Quote Originally Posted by Shadowybeige View Post
    The main point that I tried to make (maybe not clearly enough) is that the WAY JCM maps inverted mass matter is different from the way dark matter is mapped. The weak gravitational lensing (which is the observed evidence to be explained) was mapped according to the concordance model, which is why we think it's dark matter, and why we think it is where it is. If we map the lensing according to the JCM, we should find the "dark matter" (in this model negative mass matter) in a wholly different location. Ideally that location would be nestled within the largest gaps between visible baryonic matter.
    Quote Originally Posted by Shadowybeige View Post
    HOW the two systems map dark matter is different because of WHAT the two systems think dark matter is, therefore WHERE they conclude the actual material responsible for the gravitational warping is, will be different.
    Seriously, how else do I phrase this?
    You CAN use dark matter to support the ΛCDM-model. You CAN use negative mass to support the JCM. You CANNOT use one (specifically it's location when mapped according to that particular model) to attack the other (specifically its location when mapped according to different math). The bullet cluster is NOT evidence against the JCM for this reason.

    If anything, the idea that "the gravitational potential does not trace the plasma distribution, the dominant baryonic mass component, but rather approximately traces the distribution of galaxies" is exactly what the JCM PREDICTS would happen in such an instance. So the bullet cluster collision, if anything, is evidence FOR the JCM, not against it.


    Quote Originally Posted by Reality Check View Post
    You mentioned that JCM is invalidated somehow by problems with gravitational lensing. I suspect that JCM is invalidated because it cannot match observations of gravitational lensing.
    I assume you mean this quote:
    Quote Originally Posted by Shadowybeige View Post
    Also on that point, gravitational lensing is what makes JCM falsifiable. In the linked video, around 14min mark, Petit gives a simplified version of how dark matter is mapped with weak gravitational lensing and then claims that with negative mass the distortion is read differently. This means that if we map out dark matter via weak gravitational lensing tracking a radial distortion pattern we should find most of it in the intergalactic voids of space. If not, the JCM would be a less viable option.
    If you read it again, you'll notice that is not at all what I said.
    Not only are terms like invalidated and falsified totally different, but the requisite test would include measuring all the same "evidence of dark matter" (ie the observations of gravitational lensing) under the JCM to determine whether its prediction (that negative mass gathers in intergalactic voids) is validated. If so, then we have "evidence for negative-mass matter" and if not we have good evidence this model is bunk. But to say that the existence of the test invalidates the model implies you don't understand how falsification works (which I know is not true from reading earlier posts this forum).


    Quote Originally Posted by Reality Check View Post
    No evidence that JCM can explain the CMBR and its power spectrum.
    This one might just be me misunderstand you due to a lack of verbiage. What about the background radiation's spectrum needs to be explained? It's not the homogeneity of the early universe, since that was the literal topic of those panels and I thought it explained the basic idea quite well. However, since you're talking about something else, I need to know what it is before I can explain it.


    Quote Originally Posted by Reality Check View Post
    I suspect that JCM is invalidated because it cannot match observations of gravitational lensing. Bending of light by the Sun? Einstein rings? The empirical evidence that dark matter is non-baryonic matter from colliding galaxy clusters?
    Either you didn't read most of what I've written so far (wouldn't blame you), you are just ignoring large parts of it (rude), or you don't understand it (perfectly reasonable). Suffice to say:
    Quote Originally Posted by Shadowybeige View Post
    Notice that if there is very little negative mass, the negative energy-tensor, T(-)µν, approaches zero and the upper equation for space-time according to the positive metric gets closer to Einstein's original field equation with a cosmological constant of zero. Thus we see that the two coupled field equations reduce to the Einstein field equations of general relativity for regions of space-time where positive mass largely dominates. Therefore this model automatically fits with local relativistic observations and measurements without any ad hoc changes in the same way GR reduces to Newtonian mechanics with small gravitational potential and at low velocities relative to c.
    So, in fact, the JCM does match ALL Local observations because it ENTIRELY subsumes GR by the very nature of the model. I made this point in the original post. It can also be used to respond to your (somewhat incoherent) claim that GR doesn't have black holes. Or that the black holes in GR somehow NECESSITATE a central singularity? Or... to be honest, I'm not sure what your point was about wormholes. The whole post was a tad confusing and gave the impression that you didn't even read the paper.

    The JCM is consistent with GR in the same way GR is consistent with Newtonian mechanics. The argument that an alternate explanation for black holes somehow renders it incompatible with GR is like saying measuring the precession of the perihelion of Mercury by taking into account the warping of space renders GR incompatible with Newtonian mechanics. That's just not how science works, friend.

    In the JCM there is no dark matter just like there is no cosmological constant because the model does not need to posit or appeal to those entities in order to match (yes, I said MATCH) observational data. It simply has matter and a description of the manifold as having two conjugated metrics. From that ALONE it ASSUMES (not posits) the existence of mass moving along geodesics generated by BOTH conjugate metrics. Negative and positive mass are inherent in the model. The observational evidence to support this idea (that there is mass following geodesics according to the conjugate metric) is the very same gravitational lensing which supports dark matter, AND (not separate or distinct) the accelerating expansion of the universe which supports dark energy. Both are evidence for the JCM's dual-metric universe.

    To attack the JCM for not including a cosmological constant or for attributing the effect of dark matter to negative mass is equivalent to attacking the heliocentric model for not having epicycles!

    I still want to defend the actual model, but if things are unclear about how the model works, you gotta ask! Attacking a misconception of the model isn't going to help. Normally I wouldn't mind explaining/repeating myself but there's a limited amount of time here.

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    Quote Originally Posted by Shadowybeige View Post
    That's just factually inaccurate. ...
    That is wrong. A scientific theory is considered to be valid because scientists are convinced that it is valid because it has valid science in it and has credible evidence to support it. A valid scientific theory is written about by more and more scientists as more and more scientists are convinced hat it is valid. There is no evidence the JCM has had a growth in support over the last 40 years!

    The main point of Occam's razor is that the theories must be equal in their results. JCM is not equal to the Lambda-CDM model and thus Occam's razor cannot be applied.

    The Bullet Cluster is empirical evidence that dark matter is non-baryonic matter and so is included in the Lambda-CDM model. The Bullet Cluster is evidence against any modified gravitational theory which incudes JCM unless the JCM can match the Bullet Cluster data. Then we have the other colliding clusters.

    Quote Originally Posted by Shadowybeige View Post
    If anything, the idea that "the gravitational potential does not trace the plasma distribution, the dominant baryonic mass component, but rather approximately traces the distribution of galaxies" is exactly what the JCM PREDICTS would happen in such an instance. So the bullet cluster collision, if anything, is evidence FOR the JCM, not against it.
    That "the gravitational potential does not trace the plasma distribution, the dominant baryonic mass component, but rather approximately traces the distribution of galaxies" is a mainstream calculation using empirical data from the Bullet Cluster. Clowe et.al are stating dark matter has to be non-baryonic matter because there is no dominant baryonic mass component!

    My first formal questions:
    IF01: Cite the JCM paper with the calculation using empirical data from the Bullet Cluster.
    IF02: Cite the JCM calculation for the CMBR and its power spectrum.
    This is the fact that the CMBR does not only have a temperature and a perfect black body spectrum. The CMBR also has temperature fluctuations. A method of looking at fluctuations is a Fourier transformation to get a power spectrum. Lambda-CDM explains the power spectrum (basically the height of the 3rd peak relates to how much dark matter there is). Can JCM?
    Last edited by Reality Check; 2019-Aug-08 at 03:49 AM.

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    Quote Originally Posted by Reality Check View Post
    The rebuttal is the question: What are the predictions of the model that are unique to the model and what is the evidence supporting them? I have seen none in the thread so far.
    This was an informal question but since I am starting to ask you formal questions:
    IF03: What are the predictions of the model that are unique to the model and what is the evidence supporting them?
    GR for example predicted the precession of the orbit of Mercury and the bending of light by the Sun which partially why GR was quickly accepted as valid science.

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    Quote Originally Posted by Shadowybeige View Post
    Suffice to say:So, in fact, the JCM does match ALL Local observations because it ENTIRELY subsumes GR by the very nature of the model. I made this point in the original post.
    That is correct - you did make an assertion in the OP about "regions of space-time where positive mass largely dominates" so some questions about some local observations where "regions of space-time where positive mass largely dominates". Note that that JCM needs to justify ignoring negative matter in those regions.
    IF04a: Cite the JCM prediction for the precession of the orbit of Mercury.
    IF04b: Cite the JCM prediction for the bending of light by the Sun.
    IF04c: Cite the JCM prediction for the gravitational time dilation experiments.

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    Quote Originally Posted by Shadowybeige View Post
    ...It can also be used to respond to your (somewhat incoherent) claim that GR doesn't have black holes. Or that the black holes in GR somehow NECESSITATE a central singularity? Or... to be honest, I'm not sure what your point was about wormholes.
    I never claimed that GR does not have black holes. GR states that a central singularity must exist in GR (and this universe) - see the Penrose–Hawking singularity theorems (basically if black holes are black and their energy density is not negative then they must have a singularity).

    You wrote "As far as I could tell this was an attempt to EXPLAIN what we call "black holes" as "bridges" WITHIN the framework of GR...". GR does not have JCM's "bridges". The closest GR gets is the speculation of wormholes but these are not JCM's assumed "bridges" (wormholes have a sound mathematical background). Thus that paper cannot be "WITHIN the framework of GR". That was the point of:
    Quote Originally Posted by Reality Check View Post
    That is not what his paper is about. GR does not have his other fold. GR does not have arbitrary "bridges". GR has wormholes (or Einstein–Rosen bridges) which are not his "bridges".
    The paper is not an explanation of black holes - it is close to a fantasy about how to remove the central singularity of black holes that must exist in GR.
    The "close to a fantasy" bit is because all I have seen are cartoons supporting the FCM "bridges" so far. No mathematical support. No empirical evidence.
    Last edited by Reality Check; 2019-Aug-08 at 04:23 AM.

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    Quote Originally Posted by Reality Check View Post
    IF01: Cite the JCM paper with the calculation using empirical data from the Bullet Cluster.
    Quote Originally Posted by Shadowybeige View Post
    ...if there were a lab with the proper instruments (which there are) who were willing to indulge JPP (not so much), they could modify the code to map dark matter according to the JCM [where if, correct, most would be found in large voids]. That seems like it is a unique prediction, which the observational evidence intuitively supports according to maps of visible matter under the ΛCDM-model.
    Quote Originally Posted by Shadowybeige View Post
    the requisite test would include measuring all the same "evidence of dark matter" (ie the observations of gravitational lensing) under the JCM to determine whether its prediction (that negative mass gathers in intergalactic voids) is validated. If so, then we have "evidence for negative-mass matter" and if not we have good evidence this model is bunk.
    There have not been calculations done because the resources afforded to Petit alone don't allow for analyses of that magnitude (part of why ignoring scientific theories =/= invalidating them). Petit has mentioned on multiple occasions that his attempts to contact labs who would be able to falsify his model deny him this privilege. Clearly we disagree about how science progresses through the ages, but I hope you can at least agree that falsification of promising theories is how we weed the bad ones from the ones with "valid science" in them.



    Quote Originally Posted by Reality Check View Post
    IF03: What are the predictions of the model that are unique to the model and what is the evidence supporting them?
    GR for example predicted the precession of the orbit of Mercury and the bending of light by the Sun which partially why GR was quickly accepted as valid science.
    Even though it's pedantic, GR did not "predict" mercury's movement as much as it "explained" it. The phenomenon was very well known. This is important because if the precession of the orbit of Mercury is a "prediction" of GR, than weak gravitational lensing, the observed rotation speed of galaxies, the observed homogeneity of the early universe, and the accelerating expansion of the universe, are "predictions" of JCM (which I don't think you accept). As for actual "predictions" (claims the model makes that haven't been verified yet but could with a few computers dedicated to image-processing):
    Quote Originally Posted by Shadowybeige View Post
    I understand if you don't like that one, but what about the dipole repeller? I know that is a favorite of Petit's. I haven't kept up with explanations for the phenomenon though. Last I heard the math was under dispute. You could say that the JCM posits a large conglomeration of negative mass matter there which implies a whole series of predictions about movement of visible celestial bodies away from it (and only away from it). Not to mention, combined with the imaginary instance above, we'd be able to map supposed negative mass matter as it was attracted to and flowed towards the "supervoid". I don't know how strong the evidence is because I can't interact with the actual data, but it should be possible to find out the correlation between the model's predicted movements and measured movements.


    Quote Originally Posted by Reality Check View Post
    IF02Cite the JCM calculation for the CMBR and its power spectrum.
    This is the fact that the CMBR does not only have a temperature and a perfect black body spectrum. The CMBR also has temperature fluctuations. A method of looking at fluctuations is a Fourier transformation to get a power spectrum. Lambda-CDM explains the power spectrum (basically the height of the 3rd peak relates to how much dark matter there is). Can JCM?
    Quote Originally Posted by Shadowybeige View Post
    http://www.jp-petit.org/papers/cosmo...in-Physics.pdf

    Here's the best explanation I can find about determining how things work on the negative side. WARNING it's a little snarky. Not as bad as the other one, but still too confident for my liking.
    Specifically, sec 4 photons react to gravitational field, "If the gravitational instability cannot occur in our sector of the universe, before decoupling, we have the imprint of such primeval instability, which occurs in the negative sector. We think that this produces the light inhomogeneities in the CMB"; and sec 6 conclusion, "We point out that such primeval gravitational instability,occurring in the negative sector, make an imprint in ours, and that corresponds to the observed fluctuations in the CMB". Admittedly, this is a very poor translation and is rather hard to follow but you only asked for a citation, albeit one I already presented.



    Quote Originally Posted by Reality Check View Post
    That is correct - you did make an assertion in the OP about "regions of space-time where positive mass largely dominates" so some questions about some local observations where "regions of space-time where positive mass largely dominates". Note that that JCM needs to justify ignoring negative matter in those regions.
    IF04: Cite the JCM predictions that match general relativity.
    ...That's the core conceit of the model though; like attracts like and opposites repel. This is like asking GR to justify the idea that mass warps space. All we have are observations- but if you deny the core mathematical assumptions of a new model which allow proper explanation of those observations, there is no possibility for satisfactory evidence. If you need numbers to verify, look at Section 9: first geometrical interpretation of dark matter phenomenon in this paper, where he presents the math that supports it. If we consider the fact that negative mass bodies will only gather in gaps between baryonic matter, then the solar system should have very little negative mass indeed- most of it having been ejected to the outer reaches of the solar system by the masses orbiting the sun. Therefore these predictions are inherent in the model since all of these experiments have only been performed within our solar system (where there should be little to no negative matter).



    Quote Originally Posted by Reality Check View Post
    You wrote "As far as I could tell this was an attempt to EXPLAIN what we call "black holes" as "bridges" WITHIN the framework of GR...". GR does not have JCM's "bridges". The closest GR gets is the speculation of wormholes but these are not JCM's assumed "bridges" (wormholes have a sound mathematical background). Thus that paper cannot be "WITHIN the framework of GR".
    I think within the FRAMEWORK of a model is very different from within the ESTABLISHED HEURISTICS of a model. You seem to be confusing the two here. To reiterate, "the JCM is consistent with GR in the same way GR is consistent with Newtonian mechanics. The argument that an explanation for black holes which utilizes a second conjugate metric to remove the singularity somehow renders it incompatible with GR is like saying measuring the precession of the perihelion of Mercury by utilizing the warping of space renders GR incompatible with Newtonian mechanics."



    Quote Originally Posted by Reality Check View Post
    The "close to a fantasy" bit is because all I have seen are cartoons supporting the FCM "bridges" so far. No mathematical support. No empirical evidence.
    Idk, this, certainly looks like mathematical support to me. Course, I can't confirm whether the math is correct, but the inferences are valid even if the argument isn't sound. As for empirical evidence, I don't know what constitutes empirical evidence for a singularity. I've never heard of anyone using direct experiential reference when talking about singularities. You can't even say black holes are observational evidence for a singularity because they're just as much observational evidence for the JCM's "bridges" (or any theory which posits an alternate falsifiable explanation). Strong gravitational warping, Einstein rings, and high frequency radiation are empirical evidence to support the existence of black holes, not the mathematical singularity at the center of a black hole. If you put forward empirical evidence for the singularity, I'll try to dig something up. Otherwise it seems like a misguided avenue of approach.
    Last edited by Shadowybeige; 2019-Aug-08 at 08:48 PM.

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    Quote Originally Posted by Shadowybeige View Post
    There have not been calculations done because the resources afforded to Petit alone ....
    IF01 answer = no calculations for the fundamental evidence for dark matter published in 2006 (Bullet Cluster), 12 years ago! It is not Petit alone - the papers have co-authors. This makes any statement by anyone that JCM explains the evidence for dark matter obviously wrong. JCM is just one of many MOND theories that explain only the galaxy oration curve evidence for dark matter.

    Petit emphasizes how dubious JCM is - he seems ignorant about where astronomical data is stored. The Bullet Cluster and other data is not stored in "labs" and does not need privileges to be accessed. Astronomical data is generally in publically accessible databases. Just read A direct empirical proof of the existence of dark matter
    ∗BASED ON OBSERVATIONS MADE WITH THE NASA/ESA HUBBLE SPACE TELESCOPE, OBTAINED AT THE SPACE TELESCOPE SCIENCE INSTITUTE, WHICH IS OPERATED BY THE ASSOCIATION OF UNIVERSITIES FOR RESEARCH IN ASTRONOMY, INC., UNDER NASA CONTRACT NAS 5–26555, UNDER PROGRAM 10200, THE 6.5 METER MAGELLAN TELESCOPES LOCATED AT LAS CAMPANAS OBSERVATORY, CHILE, THE ESO TELESCOPES AT THE PARANAL OBSERVATORIES UNDER PROGRAM IDS 72.A-0511, 60.A-9203, AND 64.O-0332, AND WITH THE NASA CHANDRA XRAY OBSERVATORY, OPERATED BY THE SMITHSONIAN ASTROPHYSICS OBSERVATORY UNDER CONTRACT TO NASA.
    There is no reason why Petit or his co-authors could not apply JCM to astronomical data, especially for Bullet Cluster.

    Science does progress by falsifying scientific theories. Scientists though have to be convinced that it is worth their time, money and effort to falsify a theory. They do not waste time on obviously wrong theories because they know that everyone can see that the theory is wrong. They do not waste time on old (42 years for JCM) theories that have not gained support because these are likely have already been evaluated as wrong by experts. They do not waste time when they see authors of a theory stating obvious ignorance about astronomy (Petit says dark matter is no longer required when JCM only explains galaxy rotation curves like any MOND theory - 1 line of 11 lines of evidence for dark matter).

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