Dark matter

There’s plenty of evidence for dark matter, ranging from velocity dispersion, flat galactic rotation curves, and gravitational lensing. The evidence for dark matter is so good we can even map it out:

Image credit NASA, ESA and R. Massey (California Institute of Technology), see spacetelescope.org

There’s also plenty of papers and articles about dark matter candidates. Maxim Khlopov refers to WIMPs, axions, neutrinos, mirror-world particles, extra-dimensional particles, and black holes. Andreas Ringwald refers to neutralinos, gravitinos, sterile neutrinos, and axions. Kim Griest refers to MACHOs, molecular hydrogen, MOND, axions, WIMPs, and neutrinos. And to something else. To “the ‘none-of-the-above’ possibility which has surprised the Physics/Astronomy community several times in the past”. However why that should be a surprise is something of a mystery to me.

One of our candidates is missing

That’s because one of our candidates is missing, and it’s right there in the foundation of the general theory of relativity. That’s where in 1916 Einstein said “the energy of the gravitational field shall act gravitatively in the same way as any other kind of energy”. Gravitational field energy causes gravity, and it isn’t made up of WIMPs, or axions, or sterile neutrinos. It’s none of the above. Whilst some might claim this field energy could be quantized as some kind of particle, that’s the wrong approach. That’s not how gravity works. There are no actual photons flying back and forth between the proton and the electron in the hydrogen atom. The virtual photons of QED are virtual, as in not real. They aren’t the same thing as vacuum fluctuations, they only exist in the mathematics of the model. Photons are real electromagnetic waves, but hydrogen atoms don’t twinkle, and magnets don’t shine. In similar vein you might say gravitons are real gravitational waves, but there are no virtual gravitons flying around in the room you’re in. Instead there’s gravitational field energy in the room you’re in.

Field energy is spatial energy

In his 1929 essay on the history of field theory, Einstein described a field as a state of space. He was talking about gravitational fields and electromagnetic fields, and he said this: “it can, however, scarcely be imagined that empty space has conditions or states of two essentially different kinds”. The crucial point to appreciate is that a field isn’t something that exists in space, it’s a state of space. As to what sort of state, Einstein talked about that in his 1920 Leyden Address. That’s where he referred to a gravitational field as a place where space was “neither homogeneous nor isotropic”. He finished up saying this: “recapitulating, we may say that according to the general theory of relativity space is endowed with physical qualities; in this sense, therefore, there exists an ether”. See the Wikipedia aether theories article and note the quote by Robert B Laughlin: “it is ironic that Einstein’s most creative work, the general theory of relativity, should boil down to conceptualizing space as a medium when his original premise [in special relativity] was that no such medium existed”. Laughlin also said the empty vacuum of space is more like a piece of window glass than ideal Newtonian emptiness. He finished up saying “the modern concept of the vacuum of space, confirmed every day by experiment, is a relativistic ether. But we do not call it this because it is taboo”. Einstein is supposed to have done away with the ether or aether, but in the end, he didn’t. He thought of space as a something rather than a nothing. Something elastic.

Space is modelled as an elastic solid

This is why general relativity is related to continuum mechanics. And why if you google on Einstein elastic space, you can find articles such as evicting Einstein. It was written in 2004 by NASA’s Patrick Barry and Tony Phillips. It says this: “relativity explains gravity and motion by uniting space and time into a 4-dimensional, dynamic, elastic fabric of reality called space-time, which is bent and warped by the energy it contains”. This is why we have the stress-energy-momentum tensor, which “describes the density and flux of energy and momentum in spacetime”:

Public domain image by Maschen, based on an image by Bamse see Wikipedia

Note the shear stress term on the right. That tells you space is modelled as some kind of elastic solid. Also note the energy-pressure diagonal. Space is modelled as an elastic solid that’s subject to pressure. For an analogy, imagine you have a large block of gin-clear elastic jelly, with grid lines in it so you can see what’s going on. You slide a hypodermic needle into the centre of the block, and inject more jelly. This represents a concentration of energy bound up as the matter of a massive star. It creates a pressure gradient in the surrounding jelly. Stress is directional pressure, the pressure is outwards, and Einstein’s equation Gμν = 8πTμν is modelling the way gin-clear elastic space is conditioned by the energy you added. But note that you added jelly to represent energy, and that the jelly is also representing space. Space doesn’t just have some kind of innate intrinsic vacuum energy. At some deep fundamental level, energy and space are the same thing. A solid thing.

Spatial energy is vacuum energy

But this thing is not a solid like silicone rubber is a solid. Space is a continuum, it isn’t made of matter particles, or dark matter particles. We say matter is made of energy, but we don’t say energy is made of matter. Particularly spatial energy, which is vacuum energy, because that’s what’s left when you’ve taken the matter away. It is what it is, it isn’t made of something else. Au contraire, as far as I can tell it’s fundamental: everything else is made of it. For example a gravitational field is a place where space is inhomogeneous. A wave is a dynamical non-uniformity. A photon is a transverse wave propagating linearly at c. An electron is where a 511keV photon is going around and around in the guise of a spin ½ standing wave. Standing wave, standing field. But even if the electron isn’t there, or the photon, or the gravitational field, the vacuum energy is. There’s no discernible gravitational field in a gedanken void at the centre of a planet. That’s where space is homogeneous and there’s no gradient in gravitational potential. But it’s also a place where gravitational potential is low because the vacuum energy density is high.

Inhomogeneous vacuum

As for how high, we don’t know. But we do know that the energy density is higher in a black hole where gravitational time dilation is infinite. The energy density is lower in free space well away from the black hole. In between there’s a density gradient. It’s similar for the room you’re in, which is why your pencil falls down. And where the Moon is, which is why the Moon orbits the Earth. And where the Earth is, which is why the Earth orbits the Sun. And where the Sun is, which is why the Sun orbits the centre of the galaxy. But unfortunately the FLRW metric “starts with the assumption of homogeneity and isotropy of space”. This is not a good assumption. Not when Einstein said a gravitational field is a place where space is “neither homogeneous nor isotropic”. Not when modern authors say the same thing and write papers like inhomogeneous vacuum: an alternative interpretation of curved spacetime. Or papers like inhomogeneous and interacting vacuum energy.

The contrast between aether and matter would fade away

Especially since Einstein said if we could understand the gravitational and electromagnetic fields “as one unified conformation”, the contrast between ether and matter would fade away. He was saying the contrast between space and matter would fade away. So the contrast between space and dark matter should fade away too. See does matter differ from vacuum? by Christoph Schiller. The answer is no. Because this space, this quintessence, doesn’t just have energy, it is energy, and matter is made of energy. So it’s perhaps rather prescient that “medieval scholastic philosophers granted aether changes of density, in which the bodies of the planets were considered to be more dense than the medium which filled the rest of the universe”. It would seem that Newton granted that too:

Fair use excerpt from Newton’s views on aether and gravitation by Léon Rosenfeld 1969

When it’s inhomogeneous, space has a mass equivalence and a gravitational effect. But it doesn’t interact with photons in the usual sense. It’s gin clear. It’s invisible to the entire electromagnetic spectrum. It doesn’t change a photon’s E=hf energy, because energy is conserved. Space merely bends a photon’s path when space is inhomogeneous. When it isn’t, like in the void at the centre of the planet, you wouldn’t know it was there. Because light goes straight and pencils don’t fall down. It’s similar for electrons and protons. Space only affects them gravitationally when it’s inhomogeneous. It’s also dark, and it’s cold because it doesn’t consist of fast-moving particles, so it fits the bill in every way you can think of. Particularly when you think of black holes and the early universe. Because as Stephen Hawking said, the universe is like a black hole in reverse. We’ll come back to that another day.

The raisin loaf analogy

So, we have our vacuum energy. When it’s inhomogeneous it has a gravitational effect. Meanwhile the contrast between space and matter is fading away, and space is dark. It sounds promising. But there’s something else we need, starting with a raisin loaf:

Image by NASA, see Universe 101 by Britt Griswold and Edward Wollack

The raisin-loaf analogy likens the expanding universe to a loaf in an oven. The loaf rises and expands. It gets bigger, but the raisins don’t. They represent the galaxies, and the thing to remember is space expands between the galaxies but not within. That’s because each galaxy is gravitationally bound. Something else we need to accompany the raisin loaf is conservation of energy. Do you know of any situation in which energy is not conserved? I don’t. I don’t know of any over-unity free-energy perpetual motion machines. So when space expands, conservation of energy tells me the spatial energy density must reduce. Not stay constant.

Space expands between the galaxies but not within

This is important because there’s more than one way to skin Schrödinger’s cat. To recap, Einstein modelled space as a continuum, akin to some kind of gin-clear ghostly elastic jelly. Let’s make that a dark jelly, with white grid lines. When you inject more jelly in the middle you create a pressure gradient in the surrounding jelly. Curved spacetime is essentially a plot of this pressure gradient. It isn’t the curvature of the grid lines. Like John Baez said, curved spacetime is not curved space. Space isn’t curved where a gravitational field is. Instead, like Einstein said, it’s inhomogeneous. Then when the inhomogeneity is non-linear such that a plot of it is curved, the result is what we call curved spacetime. So, is there another way to make space inhomogeneous? What happens when space expands between the galaxies but not within? Let’s start with two galaxies close together. Let’s take a look at some grid lines, but let’s also take a slice through the middle to avoid getting confused by the curvature of the galaxies. Then we can depict each galaxy’s gravitational field as inhomogeneous space, like so:

Galaxy images by NASA

When space expands between the galaxies but not within, the energy density of space between the galaxies reduces by virtue of conservation of energy. So the inhomogeneity increases. Like so:

Galaxy images by NASA

And what’s a gravitational field? Like Einstein said it’s a place where space is “neither homogeneous nor isotropic”. So when the universe expands, when space expands between the galaxies but not within, those galaxies end up with deeper gravitational potentials. You can liken it to an upside-down rubber sheet analogy. A gravitational field is normally shown as a bowling-ball depression, but turn it over so it’s a mountainous hump in a plain. Injecting that gin-clear ghostly elastic jelly makes the mountain bigger. But expanding the universe is like lowering the whole plain. The mountain gets bigger in a roundabout way. So do the gravitational fields of our galaxies. Each and every galaxy, unless it’s bright and shiny and new, is of necessity surrounded by a region of inhomogeneous space. Caused by the non-uniform expansion of space. And inhomogeneous space is what a gravitational field is. So each and every galaxy has rather more gravity than you might expect.

Age matters

The situation is similar for clusters of galaxies. The space within the galaxies doesn’t expand, and nor does the space between the galaxies of the cluster. So the galaxies end up embedded in a region of denser space, surrounded by a density gradient. A place where space is neither homogeneous nor isotropic. A gravitational field. In our upside-down rubber sheet analogy, the cluster is a massif. Expanding the universe is like lowering the surrounding plain so the massif gets more massive:

Dark matter map by Priyamvada Natarajan et al, see mapping substructure in the HST Frontier Fields figure 28

See the NASA article galaxy clusters reveal new dark matter insights. It dates from 2016, and concerns a study of 8,648 galactic clusters by Hironao Miyatake and 6 other authors. The article says the internal structure of a cluster is linked to the dark matter environment it’s in. It quotes co-author David Spergel saying this: “our work has shown that ‘age matters’: Younger clusters live in different large-scale dark-matter environments than older clusters”. Yes, age matters. Because an old cluster is going to look like its embedded in more dark matter than a young cluster. Because the surrounding space has expanded more. Hence you can read articles such as dark matter less influential in galaxies in early universe on PhysOrg dating from March 2017. It concerns a paper by Reinhard Genzel and 31 other authors on strongly baryon-dominated disk galaxies at the peak of galaxy formation ten billion years ago. What they found was intriguing: “unlike spiral galaxies in the modern Universe, the outer regions of these distant galaxies seem to be rotating more slowly than regions closer to the core – suggesting there is less dark matter present than expected”. There’s an accompanying illustration which also appears in the Scientific American reportage. I’ve flipped it horizontally to make fit better with the excellent animation by Ingo Berg in the Wikipedia galaxy rotation curve article:

CCA 4.0 image by ESO/L Calçada see ESO public images                                            CCASA image by Ingo Berg, see Wikipedia

The early spiral galaxies have “normal” rotation curves wherein velocity diminishes with distance, like you’d expect if there was no dark matter. The contemporary spiral galaxies have flat rotation curves. Something has clearly changed whilst space has been expanding. What can it be? Why I rather think it might be something called space.

A problem for structure formation

Take a look at the citations for the 2017 paper by Genzel et al. There’s corroboration in falling outer rotation curves of star-forming galaxies at 0.6 < z < 2.6 probed with KMOS3D and SINS/ZC-SINF. It’s by Philipp Lang and 27 other authors. They said “this outer fall-off strikingly deviates from the flat or mildly rising rotation curves of local spiral galaxies of similar masses”. That doesn’t sit well with dark matter’s supposed role in structure formation, where it’s said to form the “seeds into which the baryons could later fall”. Mark Swinbank is diplomatic in his 2017 Nature letter distant galaxies lack dark matter. He said “surprisingly, galaxies in the distant Universe seem to contain comparatively little of it”. Alexander Dolgov said new data strongly supports an inverted picture. Mordehai Milgrom wrote about high-redshift rotation curves and MOND in 2017, saying a0 may be varying with cosmological time. Andy Biddulph really spits it out in observational support for bottom up quantum gravity. He said it’s “contrary to the standard model of galaxy formation which supposes a dark matter halo about which baryons condense”. Quite. Which is why Genzel said it’s going to be an interesting time.

Old galaxies and clusters contain more dark matter than youngsters

That’s because older galaxies definitely appear to contain more dark matter than younger galaxies. The paper by Lang et al says star-forming galaxies at larger look-back times are more baryon-dominated, with the baryon fraction increasing with redshift. They refer to Förster Schreiber et al 2009, van Dokkum et al 2015, Burkert et al 2016, Wuyts et al 2016, Price et al 2016, and Stott et al 2016. Also see the 2009 NASA report Hubble provides new evidence for dark matter around small galaxies. That’s where Christopher Conselice said this: “these dwarfs are very old galaxies that have been in the cluster a long time. So if something was going to disrupt them, it would have happened by now. They must be very, very dark-matter-dominated galaxies”. The underlying paper is Hubble Space Telescope survey of the Perseus Cluster – I. The structure and dark matter content of cluster dwarf spheroidals by Samantha Penny, Christopher Conselice, Sven de Rijcke, and Enrico Held.

The Bullet cluster

Talking of clusters, the Bullet cluster is said to provide the best evidence to date for the existence of dark matter”. You can find composite images such as the one on the Chandra X-ray observatory website, in the 2006 article NASA finds direct proof of dark matter:

Credit: X-ray: NASA/CXC/CfA/M Markevitch et al; Optical: NASA/STScI; Magellan/U Arizona/D Clowe et al; Lensing Map: NASA/STScI; ESO WFI; Magellan/U Arizona/D Clowe et al.

The picture is composed of an optical image showing orange and white galaxies, an X-ray image showing hot gas in pink, and a blue overlay of dark matter inferred from lensing observations. Most of the baryonic matter is in the form of gas rather than stars. This gas was slowed and heated to 160 million degrees in a 6 million mph collision. It was left behind, whilst the dark matter wasn’t. Hence the lensing is strongest in two separated regions near the visible galaxies. See the animation on the Chandra photo album. Strictly speaking the Bullet cluster is the one with the bow shock trailing behind it, but people tend to refer to both clusters as the Bullet cluster without thinking too much about it. It’s similar for MACS J0025.4-1222 which “provides independent, direct evidence for dark matter and supports the view that dark matter particles interact with each other only very weakly”. People presume dark matter consists of particles without thinking too much about it.

Abell 520

They don’t think too much about Abell 520 either. See the 2012 Chandra article dark matter core defies explanation in NASA Hubble image. The associated press image and caption says “the result could present a challenge to basic theories of dark matter, which predict that galaxies should be anchored to dark matter”. Again the galaxies are orange and white, the pink is hot gas which is evidence that a collision has occurred, and the dark matter is shown in blue:

Credit: X-ray: NASA/CXC/UVic/A Mahdavi et al; Optical/Lensing: CFHT/UVic/A Mahdavi et al, see the Chandra photo album

Like the Bullet cluster there’s a bow shock, but pointing 45° down to the right rather than straight left to right. However unlike the Bullet cluster there’s dark matter in the middle, and apparently no dark matter around a group of bright galaxies on the left. See the Canada-France-Hawaii telescope website for a good write up in their article dark matter core defies explanation. It says this: “the team has proposed a half-dozen explanations for the findings, but each is unsettling for astronomers. “It’s pick your poison,” said team member Andisheh Mahdavi”. The article refers to a study of the dark core in A520 with Hubble space telescope: the mystery deepens. It’s by Myungkook James Jee, Andisheh Mahdavi, Henk Hoekstra, Arif Babul, Julianne Dalcanton, Patricia Carroll, and Peter Capak. They offer a variety of possible causes, namely a compact high mass to light group, a contribution from neighbouring substructures, a distant background cluster, the ejection of bright galaxies, the collisional deposition of dark matter, and a line-of-sight filament. In a later paper in 2014 the first four authors favour collisional dark matter. What they don’t offer is a none of the above possibility. The possibility that dark matter is as smooth as hell. That it’s more smoothly distributed throughout space than previously thought. So much so, that it doesn’t consist of particles.

Filaments of the large scale structure

I think we’ll get there in the end. But meanwhile take note of the 2008 paper Cluster Abell 520: a perspective based on member galaxies. A cluster forming at the crossing of three filaments? It’s by Marisa Girardi, Rafael Barrena, Walter Boschin, and Erica Ellingson. Their results suggest that “we are looking at a cluster forming at the crossing of three filaments of the large scale structure”. Also note that the observable universe is comprised of “galaxy groups, galaxy clusters, superclusters, sheets, walls and filaments, which are separated by immense voids, creating a vast foam-like structure”. This structure isn’t just made of galaxies, just as a raisin loaf isn’t just made of raisins. The raisins are only a small fraction of the whole. Take away the raisins, and you still have a loaf. A foam-like inhomogeneous structure that’s a something rather than nothing. In similar vein there are no galaxies in the centre of Abell 520. But there are lensing centres. Because space itself is not homogeneous, and nor is its expansion.

Space is dark and there’s a lot of it about

I suppose this non-uniform expansion of non-uniform space means gravity is “modified”. Which in a way means Milgrom was always half right. The same goes for the people who talk about dark matter in non-specific terms. But not for the particle physicists. They’ll never find those supersymmetric WIMPs. They’re out on a limb because they don’t understand the nature of the electron or why there are no magnetic monopoles, or how gravity works. They can’t see what’s hiding in plain view because they haven’t listened to what Einstein said. Their general relativity is an ersatz secondhand general relativity that doesn’t even acknowledge that light curves because the speed of light is not constant. Or that Einstein said space is neither homogeneous nor isotropic, that it’s the aether of general relativity, and that the contrast between space and matter would fade away. What’s a quantum field? A state of space. How many states of space are there in any one place? There can only be one. What’s the state for a gravitational field? Inhomogeneous. So after forty years of no-show exotic particles, what’s left? What’s the none of the above possibility? Inhomogeneous space. That’s what dark matter is. Inhomogeneous space with its inhomogeneous spatial energy which has a gravitational effect. Because space is dark, it has its vacuum energy which has a mass equivalence, and there’s a lot of it about.


This Post Has 35 Comments

  1. Andy Hall

    I have not really managed to dig into the aether debate to the extent of understanding why the opinion appeared to win out that vacuum was nothing. It could be the conclusion of the Michelson-Morley experiment failing to detect aether. It could be the theory of special relativity replacing the role of aether with the space-time continuum. What I generally pick up on is that the “redundancy” of aether after relativity seems to have consigned the concept to being a fringe or even crank idea. The thrust of the current article on Dark Matter is that we should consider aether, I would define it as space energy density, as real, and I support that viewpoint. It works for me as an intuitive way conceptualize a medium through which electromagnetic waves propagate. A medium in which observable effects, such as light waves in the form of photons can be observed. A medium in which more dense energy structures such as electrons and photons can be formed and observed just as one observes whirlpools in water as vortices. The same structures occur in air, which we can only sometimes see. The same sorts of vortex structures also occur observable as lightning tornadoes at tiny scales. I have a booked by R.A. Ford called “Home made lighting”. that provides photographs of the millimeter scale lightning tornadoes. The question then becomes, why does aether remains a a taboo concept?

    What I will say additionally, is that the inherent intellectual appeal of the idea of an aether is supported by the maths I have done. As alluded to previously, my work supports the position of aether having properties and being directly related to energy. It appears that space at the nano-scale (atomic) and universal scale can be described with geometric relationships that relate directly back to fundamental constants. I will publish an article shortly that explains how a newly defined constant “a”, defined as a=c^4*h relates the values of photonic energy and maxwell’s electromagnetic properties of free space and thus directly relates energy and mass, unifying the concepts of photon energy and mass with an underlying mechanism. Hence the properties of aether are directly related to electrons, electrons can be related in combination to the mass in protons. Rearraging this relationship as c=(a/h)^(1/4) gives you the speed of light defined in terms of h and “a”. “a” appears to be a maximum energy density values and relates to the maximum energy you can fit into a geometrically defined space.

    Until I have written more I can only provide you with the teaser that h, Plancks constant can be defined as h = a/(Z0^4*eps0^4). You should check the numerical values. Eps0 is the permittivity of free space and Z0 is the impedance of free space. Plancks constant up until now has remained an empirical constant found from experiment and the value of Plancks constant has not been understood in terms of other constants. In stating that there is an underlying geometrical relationship between energy as light, I am treading a path that has remained an apsiration for science for a long time.

    I get the impression from reading your blog that you are not in favour of mysteries for the sake of mysteries. I prefer answers to “unanswerable mysteries”, that people not withstanding like to ask for grant money to study. It seems that the pursuit of unanswerable mysteries is good grant fodder for keeping researchers in business. There is a prospect that a lot of those mysteries will be cleared up and found to exist only because of incorrect assumptions in the theory that has previously been applied. Hence, infinity and zero need to be put in their proper place. The physical interpretation of these values needs to be correctly defined.

    Intuitively a cube of volume 1/c^3, rotating for a unit time of length 1/c gives units of energy of 1/c^4 and therefore an energy density for a frequency of 1 Hz of h/(1/c^4) = h*c^4 = a. However, these subjects require a more extensive treatment and a single comment on a website is not the place to explore them fully.

    I still think you are doing an outstanding job with these blogs. I think with this one you have really excelled with the clarity of the analysis and making the argument for the energy of space as the answer to the mystery of dark matter.

    The only point I take issue with specifically is the discussion around expansion. I don’t agree with the idea of expansion. Therefore, it is not your proposition that I have an issue with but the current generally held opinion that space is expanding. Once you have accepted the idea of energy in space with an inhomogenous distribution causing the observation of gravity in the vicinity of large masses, i.e. collections of high energy density spaces (atoms), it is less of a stretch to imagine that only the very large scale there is a variation in the energy density that space can support. If you take the analogy of ocean waves speeding up as they get into shallower water and conversely slowing down as the water gets deeper then light waves would be seen to blue shift with increasing distance / time on a very large scale in the universe. What I am proposing is that the observable universe is an entity in its own right and that the energy density at the edges is a shallower because the rotational velocity at the far distant edges is at its highest. Hence, we don’t live in an expanding universe we live in a rotating one. Everything in our universe is rotating its is only the speed that changes.

    Now, if we are in a universe of definite extent, that is rotating and with energy distribution defined by constants, you might expect that the total energy of that universe is a definable constant. The size / age of the observable universe would be a constant and the Hubble Constant could indicate the increase in energy density from the edge towards the centre of rotation of the observable universe. I have provided an overview of the maths for a calculation of the age of universe in terms of constants on my web page http://www.abstractinventions.uk/page13.php?id=13. If you substitute for “a” above into that formula the age of the universe in seconds simplifies to Tu = a*c^2/1.03^(10/3). I proposed another new constant H1 that is the age of the universe multiplied by the Hubble constant. That shows that a constant related to geometry can be defined at the scale of the universe and allows the hubble constant measured for the distant universe to be defined. I understand this is all postdiction and number fitting but it creates a mathematical model founded on geometrical principles. The web page defining H1 and hence H0 is here http://www.abstractinventions.uk/page15.php?.

  2. Andy Hall

    Typical, there is an important typo in the last post. h = a*Z0^4*eps0^4 (Z0=376.730312, eps0=8.85418e-12, a=c^4*h = 5.35228) gives a good approximation or a definition of h = 6.626046e-34. I could have recast the formula in terms of mew0, the magnetic constant as h = a*mew0^4/Z0^4 where mew0=4*pi*1e-7. In either case a clear numerical connection between h and electromagnetic constants of vacuum is indicated, implying vacuum energy is linked to mass because Planck’s constant has units including mass.

  3. John Duffield

    I don’t know why aether is somehow taboo, Andy. Nor does Nobel prizewinner Robert B Laughlin, see this: https://en.wikipedia.org/wiki/Aether_theories#Quantum_vacuum. It’s one of those things that contributes to the mess that is contemporary physics.
    Your maths sounds interesting. Especially since I think of space and energy as being the same thing. And because I like electromagnetic geometry. It shouldn’t be some big surprise because we have TQFT, not that it gets much of a mention. Nor does Andrew Worsley’s stuff on powers of c. Stuff like this: λ = 4πn / c^1½. The 4π is there because we’re dealing with a sphere, and the n has the right dimensionality and a value of 1. (I think you should look at spheres rather than cubes). Yes, the properties of space are directly related to electrons because h is what it is. And h is what it is because it’s something like an elastic limit, permittivity being an inverse shear modulus and permeability being a density. An energy density that is in effect a spatial density.
    No, I’m not in favour of mysteries. There’s too many physicists who peddle mystery because mystery sells. They use it to promote physics and say things like “Nobody knows! Woo!” What they don’t want is somebody saying somebody does know. They don’t want the mystery solved. They aren’t behaving like scientists. The situation is like this: if you pay a bunch of people a handsome salary to search for the Holy Grail, you will guarantee that they will never find it. Because if they do, that’s the end of the handsome salary.
    Thanks re this blog. I realised a while back that I’d accumulated considerable knowledge and ought to get it down, and get it “out there”. I run a forum, see https://physicsdiscussionforum.org/ but I thought I’d do a blog-style thing instead. I don’t know why we haven’t been reading about dark matter as spatial energy. I wouldn’t be surprised if there’s dozens of papers that have been saying it for decades, but we didn’t get to hear about them because too many people have been peddling WIMPs for way too long.
    As for expansion, we’ll have to agree to differ on that. Because space has this “elastic” nature, and IMHO it’s like it’s compressed elastic. Squeeze a stress ball down in your fist, then let go. Do you know what a rotating universe would be? One big magnetic field. As for the age of the universe, I don’t think it’s 13.8 billion years. Note that the speed of light varies in a gravitational field, and that in a black hole, it’s zero. So in the early universe, the very early universe, what was c? I think it was zero. Let’s talk more about this after the coming articles.

    1. Matt Bruce

      If the space within the galaxies has a higher energy-density than the space between the galaxies then as the space around the galaxies keeps expanding, it would necessitate for us to observe an ever increasing density of dark matter within the galaxies while this density between the galaxies keeps decreasing. But why do we not observe any such increase in dark matter within our galaxy? Or even observe an ever increasing Planck energy within our galaxy?

      1. The physics detective

        Matt: we do observe such an increase in dark matter. We observe older galaxies as having more dark matter than younger galaxies. We’d have to observe our own galaxy for millions or even billions of years to notice a difference.

  4. Andy Hall

    Hi John, just to follow up on my comments above I have posted the following initial page that presents what I wrote above in a tidier form and gives an indication of the extent of where my work has taken me. http://www.abstractinventions.uk/page30.php?id=3
    Unless any good reason turns up along the way, I will post the rest of my current initiative linked to the latter page and you can let me know what you think. It is all a work in progress so it will likely appear drip fed.

  5. joao carlos holland barcellos

    The secret of dark matter finally revealed.

  6. Akis

    Hi Alan,

    Wow, great input, very very interesting stuff this paper! 🙂 thank you very much for sharing!

    From the paper:

    If we adopt the “Decreasing Universe” where the gravitational field shrinks the space in which it crosses, we find that the accelerated separation of galaxies, often explained by the so-called “Dark Energy” is a kind of “illusion” resulting from this space contraction and, therefore, unnecessary. The “Dark Matter”, on the other hand, can also be explained by the same effect of the gravitational contraction of our space, since the radius of the galaxies is observed as greater than it really is, consequently, the speed of translation of a star is seen as above-expected with the observed baryonic mass, providing the false impression that there is an extra, invisible matter responsible for the effect.”

    So practically the ‘Decreasing Space’ model suggests that in reality gravitational field shrinks objects/space!
    Thats really crazy!..thats exactly what my (also) 2016 Universe simulation/viz model is like, (decreased space) ie the ‘denser’ the space, energy wise / the stronger the gravitational field,..the greater the object/space contraction in that area of space!
    Funnily I was actually commenting on this model of mine on John’s BH article just couple days ago..excellent timing your post! Its amazing to see someone else having thought of a very similar universe model and also around the same time!
    Very interesting that such a model would alltogether get rid of the need for the existance of dark matter and dark energy!
    It all makes sense..

    1. John Duffield

      I’m afraid it doesn’t make sense Alan. If it did, it wouldn’t be the Shapiro delay. Light goes slower when gravitational potential is lower. That’s why optical clocks go slower when they’re lower. It’s as simple as that. When you work things through you’ll find dark matter and dark energy are simple too.

  7. C G /praetorian /pyrrhovonhyperborea

    Gotta say, I find it hilarious to think, that someone who smashes his head against the wall of ridiculous common places of modern day physics, time and time again, would start a blog agreeing to the modern day “phlogiston” that is “Dark Matter theory”.
    Even though you do give a nod (or at the very least mention) to something like MOND, the idea, that there was some dark matter that we cannot see or touch or that interacts with any “regular matter” electromagnetically in any way, still, you do not find fault with that. You merely complain that your theory isn’t being pondered.

    I think one is already on the wrong track, to mention “MOND” as some sort of “dark matter candidate”, as it does the opposite of what “dark matter” is supposed to do, strategically. MOND tries to expand upon the underlying theory of gravity, to incorporate the seemingly contradictory findings you mentioned, whilst “dark matter” acts as a hot-fix, rather, an ad-hoc theory, an attempt to “make observation fit the theory”, rather than adjusting one’s theory to fit the observation (by introducing new, bizarre, exotic forms of matter never seen or heard, not before, nor ever since): a defining difference I once learned to separate religious – from scientific reasoning …

    When I hear “dark matter”, I think of Carl Sagan:
    “… Now, what’s the difference between an invisible, incorporeal, floating dragon who spits heatless fire and no dragon at all? If there’s no way to disprove my contention, no conceivable experiment that would count against it, what does it mean to say that my dragon exists? Your inability to invalidate my hypothesis is not at all the same thing as proving it true. Claims that cannot be tested, assertions immune to disproof are veridically worthless, whatever value they may have in inspiring us or in exciting our sense of wonder. What I’m asking you to do comes down to believing, in the absence of evidence, on my say-so…”
    What does it change, in this light, to point at the observational “evidence”, when all that it stands witness to is the shortcoming of our theory to explain what we think we are seeing. The contradiction “may” come down to what we “are not seeing”, sure; and considering that we are starting to believe, that the Halo of a Galaxy like the Milkyway is way larger and more filled with dust and gas than we thought to know, like other hard to see objects may still play a role in all that.

    All we can say for sure is: “there is a problem”; however, “dark matter” is nothing short of a prejudice, that keeps on furthering said pre-conception, that the answer must come down to a – “something”. But going beyond even theories like MOND -which does represent scientific forms of reasoning, contrary to “dark matter theory”-, I’d ponder, if there was more than just some mechanism to expand upon, like modifying newtonian physics, but rather a dynamic that develops this picture we are seeing over the billions of years that brought us here.
    Your idea further down below has some of that — but it seems more like some intellectual sleight of hand, when you repackage the rubber sheet analogy to resell it as the dark horse of answers to this very problem.

    One of the biggest blunders in all this seems to be the agreement, that expansion of space happens only between galaxies/galaxy-clusters, but not within; a conviction that to me seems to violate the principle idea, that no place in the universe was special; that thinks that happen in such and such a way here, would happen in such a such way somewhere completely different also — the cosmological principle, if you will, expanded to the underlying mechanisms, not just the distribution of matter.
    I also find it puzzling, why a theory such as “dark energy” even exists, to manipulate another finding to fit the theory of — of what, actually? For energy, be it “dark” or not, to have any effect, there has to be a mechanism to “transform” said additional quantity, in another form of energy; and a definition, a formula for that, in which to insert those numbers if we wanted to check if our theory of it makes any sense.
    Why does space expand at all? – I believe the answer to this will not only “solve” the otherwise disjointed “dark energy problem”, but also, at the same time, that of “dark matter”; as ultimately, I wager, those two are just 2 sides of the same coin.

    There is no reason for me to think, that space between galaxies was acting fundamentally different to space within; the same mechanism that is at work “there”, has to be at work “here”; heck, I could even picture “here” being it’s epicenter, if my suspicion should turn out to be correct.
    You say, spacetime builds up a plateau of sorts (you speak of a “massif”) in older galaxies — why should it not, if we stay true to the original direction of the analogy, carve out a valley instead?
    If matter always existed in a dynamic universe that was expanding, each and all equilibrii within it. moving bodies orbitting one another (like Starsystems, like entire Galaxies) must find their respective equilibrium within that framework, i.e. they are constantly “battling” an additional, invisible battle against said development. I call it “negative gravity”, just as a preleminary picture for that stream matter is battling.
    If we see Systems stay, seemingly, at constant dimensions within a greater universe that is not constant in it’s dimensions, a tiny bit of that which “draws” bodies inwards has to be hidden from our eyes.

    An all encompassing theory of gravity, I propose, will yield the answer. As the full understanding of the interaction that matter has with the underlying medium, be that a corporal medium (corporal in the sense of an energy-field, some elastic fluid, superfluid or what have you); as a transformative interaction with a not perfectly elastic medium, that leaves its marks, where we think to see only continuity. (it’s probably the most basic premise for science, that for anything to happen, “something’s gotta give!”, the principle of cause and effect, and, as an extention to that, the principle of the conservation of energy; both would indicate, that expanding spacetime would naturally mean a qualitative transformation to the medium itself as it gets stretched out over longer and longer distances.)
    If so, older galaxies would naturally “look different”, than younger ones, if we had eyes to see the invisible. Sure, your massif-idea may be re-interpreted to mean “just that”; but the way you arrived there, to me, seems to point towards the opposite, as far as suspicions go of how to solve the “mystery”. You want to see a “more” overtime, while it seems more plausible to see a “less”, as the underlying medium is thinned out, and the “excavations” of said transformation are pushed away to the outside, for voids and super-voids to grow and grow, further and further. And as the medium gets thinned out, the matter remaining in that range finds all it’s relationships (gravity, orbits around one another) shifted, as the balance between the different forms of energy remaining in the local system, of matter (“rest energy”; but also the energy that resides within in the form of heat etc.) vs. the “intergalactic medium”/space itself, gets shifted towards the former; i.e. the “same” bodies that formerly would have needed “x” to do[/keep doing] what they are doing, now only need “x*0.9”, then “x*0.8” and so on and so forth, to do “the same”.
    Even more so, it could very much be the case, that, given enough time, in a system like that, the preconditions to what constitutes a black hole may actually get – lowered, to the point, where every remaining sun, trillions upon trillions of years in the future, would also collapse in on itself. Atleast that seems to be a theory, which to test or falsify, seems to be ever so slightly more “In reach”, than hawking radiation’s conjecture of evaporating black holes. (it’s beautiful to have basically untestable theories, and be remembered for them. As thereby you can never be disproven, and stand the test of time as one of the all time greats of scientific quak — forever! . . . am I right, Steven H.?)

    If my suspicion is correct, we’d even expect bodies at the edge of galaxies to speed up over time; not just by a tilting of the underlying balance of spacetime and matter, but also because of that invisible extra bit of gravitational “pull”, that was battling the expansion of space all the time (“negative gravity”, as my working title goes); like it was actually falling inwards, all the time, whilst the optical doesn’t quite show that to our eyes for reasons stated above. Naturally, such a process would be more pronounced at the outskirts of the galaxy, but take billions upon billions of years to unfold.

    PS: not sure, what name I gave myself underneath, last time (years back) I commented on your blog…

    1. the physics detective

      Praetorian: I don’t think comment length counts, I think it’s more likely that in a long comment you’re more likely to mention a medical word that triggers the spam detector. For example, try putting v i a g r a in a comment. Sorry, I can’t find your prior comments. I searched the whole blog on praetorian and there were only three comments by you. With 1,346 comments in all, it wouldn’t be easy to find if you used a different name.
      As for dark matter, you have to read things like https://physicsdetective.com/how-gravity-works/ and https://physicsdetective.com/misconceptions-in-gravitational-physics/. What shapes my thinking is Einstein talking about space as the sole medium of reality. And William Kingdon Clifford’s space theory of matter. Space is real, waves run through it, those waves can get trapped in closed paths, and that’s about it. As for why space expands, IMHO it’s because it’s not just like elastic, it’s like compressed elastic. Get a stress ball and squeeze it. Then let go, and watch it expand.

      1. CG

        Found it; underneath stuff like the nature of time and the speed of light is not constant; “CG” it was (not “C G “), what I called myself there.

        Gotta say; expected a bit more of an answer; but alas! – the blog-article I answered to is 2 years old, so there’s that.

        One quick question though:
        “…Space is real, waves run through it, those waves can get trapped in closed paths, and that’s about it….” (something I could see myself getting behind) — what in the world then is a neutrino? – particularly the “massles” variant is the one I am puzzled by; how is that supposed to work, and why would it still be relevant in a model like that?
        I’d have to picture it to be point-like (-something neither you nor I seem to be fond of?-) in order for it to have “no mass”; otherwise: anything that has dimensions (i.e. is NOT point-like) would have to experience gravity (it wouldn’t make sense if it didn’t), when moving through space; heck, a wave moving round and round would experience gravity by virtue of that all alone.

        I still wonder, either way, why you subscribe to the idea of “dark matter”; not that there is something in our observations that contradicts the theory we were using in an attempt to explain exactly that; but the ad-hoc theory itself. It seems rotten logic from the start, at odds with the very basics of scientific reasoning. “The experiment contradicted the predictions of our model — THEREFORE there must be some invisible stuff skewing the picture, that our perfect theory could not have accounted for!”
        The entire purpose of my comment was about exactly this. And to show, what I deem a more reasonable, skeptical approach in answering the conflict.

        1. The physics detective

          CG: I’ll have another look at your older comments. And again, I’ll have to reply properly to this comment later. Meanwhile you might want to take a look at this: https://physicsdetective.com/the-neutrino/. I think the neutrino is more like the photon than the electron. I think it’s a rotational wave, something akin to a travelling breather.

        2. the physics detective

          I subscribe to the idea of “dark matter” because we see flat galactic rotation curves, which implies there’s something causing extra gravity that we can’t see. However I don’t think it’s actually matter. I do not believe in WIMPs. The important thing to note is that a concentration of energy causes gravity. This energy often exists as matter, but not always. Note that Einstein said “the energy of the gravitational field shall act gravitatively in the same way as any other kind of energy”. That’s spatial energy. Einstein described the gravitational field as inhomogeneous space. And yet the FLRW metric “starts with the assumption of homogeneity and isotropy of space”. How’s that for a contradiction? Talk about rotten logic. IMHO when you read what Einstein said. you end up with an even more skeptical approach in answering the conflict.

  8. C G /praetorian /pyrrhovonhyperborea

    Did I fall victim to some automated “spam-filter”, because my comment got too long?

  9. CG

    one more thing though, even less at the heart of my initial interest:

    “As for why space expands, IMHO it’s because it’s not just like elastic, it’s like compressed elastic. Get a stress ball and squeeze it. Then let go, and watch it expand.” My own mentioning of elasticity -if that is what you reacted to here- had a different purpose.
    And I don’t think, that space itself (+ it’s “state”) was the entire reason to why space expands. – how would we see any speeding up, if that was the case?

    At least that is what “scientists” keep telling me: expansion of space is “speeding up”; – although I am having some doubts about how they derived their particular number for that so called “hubble constant” .(i)
    Even worse, I often see science-explainers (particularly those I watch for entertainment) approaching the problem, by referring to some increased redshift for far away galaxies, while it would actually be greater dimming (of those standard candles) relative to their redshift (- i.e. [relatively] LESSER redshift per dimming -), as I learned alswhere. (- o/c, absolutely speaking it will always be more, the farther we look away -). – if they were -however- indeed correct, reporting, that the redshift goes up, relatively, the farther we look away, then that would constitute a SLOWING DOWN, rather than speeding up. (ii)
    I don’t have enough people I can talk with about this, but the few times I found myself in a conversation with people from the university, they seemed to be equally confused in what is more, what is less…
    Be that as it may: if I believe what I am being told, that the expansion-rate of space was increasing, then I cannot find any logic in this, unless something beyond “just” space was driving said; “accelerating” it. The interaction of matter with space is the first place I would look to find the culprit. I think there’s more to it than what is usually been said about that.

    I could see a constant SLOWING DOWN in the [pure] squished-elastic-ball scenario to be plausible: as the “pressure” (the squeeze) unfolds into width, the elastic energy gets released, for less and less of it to remain; hence: a slowing down of the work/process that transforms one energy into another. (unless I was supposed to picture it being a ball accelerating IN space? — I highly doubt though, for that to have been your intention, given all the other stuff you usually say. The ball is the entirety of space, not accelerated anywhere, but merely unfolding from it’s high pressure form, “into itself”… that’s what I have to believe how you meant it).
    but… whatever … this article wasn’t about expansion of space to begin with, so please forgive the detour. (I just think that “dark matter” and “dark energy” will be solved with the same discovery about certain mechanics; see above)

    – – –

    i) the fact that they tend to refer to it as a “speed” and “acceleration” (rather than “rate”) and usually write it in a form Distance/Time/Distance (km/s/mparsec) already seems like a gross missunderstanding. “km/Mpac/s” would make so, so much more sense; even better: LY/MLY/Y).

    ii) They seem to forget, that they are looking back in time… any “speeding up” they would want to find that way, would have to be observed in the near vicinity, not far far away; I guess they are tripping over their own words, when they call it “speed” and “acceleration” rather than “rate”: as a fleeing that we (i.e. our reference frame) do, and that would impact our vision of the distant past more so than the local group of galaxies, even though that makes no effing sense, not even in itself…
    It’s almost as if they still believe what we are seeing was doppler redshift, and that cosmological redshift was just another version of exactly that. They even employ sophistry, to make one and the other “the same”. But in that model, space doesn’t unfold into itself — matter just spurts into a greater space that was already there to explore. – which defies all logic, tbh. At least if applied with some rigor and sufficient intelligence and ability to imagine any of this. Too many mathematicians and good learners who are borderline retarded, when it comes the mental effort of picturing a whole, self-sufficient model (let’s call it “savant syndrom”, to give it a nicer name). It’s utterly absurd to see those people present themselves as the heirs to Einstein, who was exactly NOT that. He had a powerful talent for imagination, and wasn’t shy to utilize it in his attempt to truely grasp the innermost workings of the world (/universe).
    But then again… anyone who writes like this (me) will be regarded as a quak; or even less than that.
    I lost interest in pursuing any academic career in those fields (or even chosing this subject for studies at the university), when I saw my physics teacher in the final 2 years of Gymnasium (“highschool”, if you will), and how he did pride himself to speak for Einstein, whilst not having even 1/10 of his curiosity or powerful mind. I probably sensed, that that place [to study] just was no place for me. It took me a long, long while, to rediscover my great interestin all these things, for that exact reason.
    Defund them, you say? – I second that!

    1. the physics detective

      Noted re your own mentioning of elasticity having a different purpose. I think we see the expansion of space speeding up because space is getting weaker. You really must read https://physicsdetective.com/a-compressed-prehistory-of-dark-energy/ and https://physicsdetective.com/dark-energy/ to understand what I’m saying here. The analogy is inflating a bubble-gum balloon in a vacuum. The skin gets thinner, so its elastic tension is less able to constrain the internal pressure. So the expansion gets faster.
      Of course, that could be wrong. It’s more difficult to answer the big questions in cosmology. But I do think this one is right. What I don’t think is right is inflation, and I think there are issues with the big bang. If you wind the clock back, what you end up with is a very slow early expansion, not a rapid early expansion.
      I’m not fond of the “tired light” theory because I think conservation of energy is just about one of the important things in physics. Because I think, that at the fundamental level, energy is the only thing that exists. A photon is a form of energy. We make matter out of energy.
      As for be that as it may, you should read my article on what energy is. I think it’s the same thing as space. I also thing energy is all there is. So I don’t think something beyond “just” space was driving the increasing expansion. Instead I think there’s less to it than what’s usually said.
      Yes, your description of the squished-elastic-ball scenario is more or less what I imagine. Only you’re missing the fact that waves run through it. Waves only do this because there’s both pressure and tension. And if space is expanding, it’s tensile strength must surely be decreasing. Play with drooping SillyPutty to see it. The drooping SillyPutty droops faster and faster as the strand stretches and gets thinner.
      No problem re the detour. You should look up William Kingdon Clifford’s space theory of matter. I think he more or less nailed it. In 1870.
      i) I think time is speeding up. A second now isn’t the same as a second ten billion years ago, just as a second near the surface of the Earth isn’t the same as a second near a black hole event horizon.
      ii) it makes sense if you’ve seen the curved line depicting the static coasting universe. See the Jim Brau image in https://physicsdetective.com/the-big-bang/
      Re doppler redshift, and cosmological redshift, see the Tamara Davis image in https://physicsdetective.com/the-big-bang/. The ascending photon is not actually redshifted. It doesn’t lose energy. As Einstein said, it’s emitted with less energy at a lower elevation. In similar vein, I think the CMBR photons don’t lose energy either.
      Yes, it’s utterly absurd to see those people present themselves as the heirs to Einstein. Especially when they contradict Einstein.
      You’re no quack. You think for yourself. Good man!

      1. cg

        My apologies;
        I just fired away with that comment of mine just now, w/o giving it a second read (bad habit)
        After that I did remember leaving in a placeholder (“[ – ]”) for something I wanted to get back to (lost my train of thought, as I put that aside for an hour to check something out in E:D); but I cannot remember what it was. Had something specific in mind, to illustrate where I saw a contradiction. So, if you will, feel free to ignore that bit, as I didn’t actually deliver on that point. Can’t remember anymore, what I was thinking of there, anyway.
        mea culpa!

        1. the physics detective

          No problemo! I thought it was fine myself.

      2. uncertainH

        Hi John,

        Thanks so much for all your historical digging, I really appreciate your blog and the work you are doing. Your references to Clifford’s Space theory of Matter renewed my interest in his work and I found this:
        You may have already read it but it’s another good historical deep dive into some of his motivations and his adherence to the concept of continuity that forms the foundation for his space theory. Questioning our fundamental assumptions, always a good place to start.

        1. the physics detective

          UncertainH: my pleasure. I hope I can do my bit to help.
          Thanks for the paper/article on Conceptions of Continuity. No, I haven’t read it, but it definitely looks interesting. I shall read that carefully, and look out for more by Josipa Gordana Petrunić. I think there’s some great stuff in the old papers. If I had my way, the historical side of physics would be part of the curriculum. Sadly, it’s just not taught, and as far as I can tell, is it not encouraged. Heck, nor is do your own research and think for yourself. People tell me they do a physics degree, and it’s all spoonfeeding and maths, and there is no questioning of fundamental assumptions at all. Meanwhile physics is going to hell in a handcart. OK, time to get off my soapbox, because it’s time for tea!

  10. CG

    To correct myself, in case that was ambiguous in it’s meaning; when I said:
    “..Gotta say; expected a bit more of an answer; but alas! – the blog-article I answered to is 2 years old, so there’s that…”
    — I was referring to this very blog, and that very comment I made about it (up there). It wasn’t meant to warm up the older debate.
    I hope this wasn’t too confusing; your answer made me uneasy for a moment, that you may have read it differently than intended.
    — I’m still just of German heritage; English is only my second language, and while I am confident in my ability to use said second language, sometimes I notice, even today, certain little nuances that escape me for a moment (when firing away with a message), that can lead to huge misunderstandings (although I keep wondering, if my more self-confident understanding of my mothertongue may lead to equal amounts of misunderstandings, while not second guessing my messages there as much, as I expect there to be an idealized reader/listener, who knows just exactly how to read/interpret what I said. Alas — that reader/listener doesn’t exist, normally; and the +0.5M German words that are out there, are regularly not “well known” by a majority of users, even well studied ones).

    1. The physics detective

      CG: rest assured, nothing you’ve said has caused me any offence in any way. It’s just that I’m too busy, too often. Yesterday was my younger son’s birthday, so I just couldn’t do much here. I had to do some work at the weekend, and couldn’t do much then either. Ditto for tonight. Sigh!

  11. Greg R. Leslie

    John, I recently read an article on SciTechDaily dated March 9th, 2021 on the research of Gerson Otto Ludwig of the N.I.S.R. of Brazile.
    This got me to reread your articles on Dark Matter Candidates,Dark Matter,& Dark Energy.
    Evidently his preliminary research is much more in line with your positions than anything else that I’ve read over the last three years!
    I know you got a full plate at work,home,Covid & Brexit woes. It will be fun to hear your thoughts, at your convenience of course.

      1. Karl

        The Ludwig article is fascinating, how the mindset of working a lifetime on MHD has lead to new insights on applications of GR. I can’t wait for your opinion on it.

    1. The physics detective

      Greg and Karl: I read the SciTechDaily article on Gerson Otto Ludwig’s paper:
      My first impression was bollocks. I thought that because as per the dark matter pie image in my dark energy article, there’s thought to be far more dark matter than ordinary matter. The percentages are debateable, but they’re something like 23% for dark matter and 4% for ordinary matter. There’s thought to be circa six times as much dark matter than ordinary matter in terms of energy-content. The article says 85% of matter is thought to be dark matter, and 15% is nearly a sixth of 85%. Meanwhile gravitomagnetism is ultra ultra weak. See the Wikipedia gravitomagnetism article: “Such a field is extremely weak and requires extremely sensitive measurements to be detected. One experiment to measure such field was the Gravity Probe B mission”. Note that it’s fairly easy to detect the Earth’s gravitational field. Just drop your pencil. Also note that when Heaviside developed gravitomagnetism as an analogy to electromagnetism (http://sergf.ru/Heavisid.htm), he talked about an “increase in the force of attraction of S on E of one two-millionth part”.
      But OK, you can’t judge a book by its cover. The popscience article is the coverage, and it doesn’t matter. The paper itself is what matters. Here it is: https://link.springer.com/article/10.1140/epjc/s10052-021-08967-3. There’s no paywall, which is good. The abstract sounds good too, if you don’t know just how weak gravitomagnetism is. I thought the introduction was OK until I got to this: “Actually, at large distances the Lorentz force due to the gravitomagnetic field effectively controls the mass equilibrium balance in view of the decaying centrifugal force. The field produced by the large disk of mass currents basically acts as a gravitomagnetic brake against the gravitational attraction. Then I said bollocks again. That’s saying gravitomagnetism is antigravity, when it isn’t. I said bollocks again when I read this: “Although filled with controversy, the studies of the galactic rotation via general relativity [16–18] reach the same basic conclusion of the present paper. Namely, the dragging effect of a gravitomagnetic component (time-space component of the metric) explains the flat rotation curve at large distances, without the recourse to dark matter. I thought bah. I also thought the rest of section 1 was huff puff and waffle.
      In section 2 I didn’t like to see the c in equation 2.3. A gravitational field is a place where the speed of light is spatially variable. Nor did I like “where Eem and Bem are the electromagnetic fields. Aaaagh! It’s the electromagnetic field. In section 3 I didn’t like the “gravitoelectromagnetic laws of Gauss and Ampère. Here’s a guy who has never read what Ampère actually said. And here’s a guy who launches into mathematical smoke and mirrors to conceal the fact that gravitomagnetism is as weak as a dead kitten. Did you see this: “The gravitoelectric force is balanced by the fluid stress” What fluid stress? It’s dust! Then IMHO it all goes downhill fast, with massive equation dumps so that you don’t notice the handwaving and the Emperor’s New Clothes, and the lack of explanation or calculation. If you beg to differ, explain section 7 to me. Apologies in advance if I glazed over and missed the trick. But if I didn’t, then what I think is this: sorry guys, but Ludwig doesn’t understand gravity or electromagnetism. So he doesn’t understand gravitomagnetism, and he conceals just how weak it is. So I’m afraid to say I ended up being disappointed. Ludwig is not in line with my positions at all. You’ll forgive me if I leave it at that.

  12. Greg R. Leslie

    No problem John, you are the expert, not me. And yes, I have no idea how week gravitomagnetism is. That is why I asked your opinion. And these kind of articles are why I always keep my dunces hat at arms length.
    Huff puff and waffle flavored bollocks it is then !

  13. Greg R. Leslie

    I enjoyed this lecture reading very much John. I could see were Einstein was influenced by Clifford’s and other’s ideas. He also was leading up to what we now call dark matter/dark enery. The very last paragraph was an eye opener. So I decided to reread your article on dark energy, and lo and behold you quote the Professor from this very lecture’s same paragraph !
    My 2 cents on what dark matter/energy is and how it works is probably not new, but here it goes: 1. the known baryonic universe is exactly as Einstein,Clifford,and others has stated. 2. It is surrounded by the non-baryonic unviverse composed of Minowski Space or a combination of Minowski/ + de Sitter/ – de Sitter Space. 3. this outer unobserved, untested non-baryonic void creates the outward pulling tension because it is infinite, cold, and larger. The baryonic center is hot ,smaller and expanding out. 4. eventually equilibrium will be achieved and the entire schiess show ends ? Maybe ? Compresses back to the middle and starts over ? Who the hell really knows ?

  14. The Physics Detective

    Nobody knows Greg. Including me. I think things like gravity and the proton are easy compared to the origin of the universe. If it ever had one. See https://physicsdetective.com/the-big-bang/. But IMHO there’s no real distinction between “the baryonic universe” and space. Space isn’t nothing. Waves run through it. And when these waves have a very short wavelength and get stuck in closed paths, we call them baryons. Hence https://arxiv.org/abs/gr-qc/9610066, where Christoph Schiller asks if matter differs from vacuum. His answer is no, and I think he’s right.
    By the by, if you were to ask me whether I thought the universe was infinite, I’d say no about that too. I don’t know this of course, But that’s my best guess. See https://physicsdetective.com/the-edge-of-the-universe/.

  15. Greg R. Leslie

    You are a cruel taskmaster John. The Christoph Schiller paper is so far over my head, trying to read and comprehend it is truly dizzying. It must be payback for me referring to SciPopDaily articles as of late. LOL!
    Give me another few weeks and another few reads and maybe some of it might make sense ?. I really need to study up on Planck Units & Schwarzchild Radius,amongst many other math concepts first.

    1. The physics detective

      Greg: I wouldn’t bother with Planck Units if I were you. See what Wikipedia says:
      The four universal constants that, by definition, have a numeric value 1 when expressed in these units are:
      the speed of light in a vacuum, c,
      the gravitational constant, G,
      the reduced Planck constant, ħ,
      the Boltzmann constant, kB.

      That’s Humpty Dumpty physics, because the speed of light varies in the room you’re in. If it didn’t, your pencil wouldn’t fall down. As for the Schwarzschild radius, there’s a c in the expression r = 2GM/c² so it isn’t ideal. Especially since the event horizon is a place where the speed of light is zero! Have a read of https://physicsdetective.com/black-holes/ to really understand black holes. I’m 100% confident that this desciption is correct. It’s easy reading too.

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