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Is dark energy becoming marginalized?

By Tushna Commissariat

Supernovae secrets: Chandra image of G299 -- a Type 1A supernova remnant.  (Courtesy: NASA/CXC/U.Texas)

Supernovae secrets: Chandra image of G299, a type Ia supernova remnant. (Courtesy: NASA/CXC/U Texas)

Here at Physics World, we enjoy a good debate and late last week, a paper appeared on the arXiv server that is bound to kick up quite the storm, once it has been peer-reviewed and published. Titled “Marginal evidence for cosmic acceleration from type Ia supernovae”, the paper was written by Subir Sarkar of the Particle Theory Group at the University of Oxford and the Niels Bohr Institute in Copenhagen, together with colleagues Alberto Guffanti and Jeppe Trøst Nielsen. It suggests that the cosmic expansion may not be occurring at an accelerating rate after all, contrary to the findings of previous Nobel prize-winning work and most of our current standard cosmological models, including that of dark energy.

Indeed, the researchers’ work suggests that the evidence for acceleration is nowhere near as strong as previously suggested – it is closer to 3σ rather than 5σ, and allows for expansion at a constant velocity. Nielsen et al. have come to this conclusion after studying a much larger database of type Ia supernovae – 50 of which were studied in the original work, while this study looks at 740 – that are used as “standard candles” to detect cosmic acceleration.

This study is sure to make many cosmologists sit up and take notice, and an interesting discussion is sure to follow. So watch this space and check back in with us, once the paper is published and we catch up with Sarkar and his colleagues.

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  1. M. Asghar

    One does need this type of work to go deeper into the dark energy problem. However, although the new database of 740 of type Ia supernovae is much more significant than
    the origilal one based on 54, the broblem may be either with the different corrections applied in the two cases to their light coming from different directions and detected on the Earth to standardise them or some of these “cosmic candles” may vary in their source-emission strenght.

    • MJBridger

      If the rate of expansion appeared to be constant, that would still be strange and against the original expectations of cosmologists who assumed it should be slowing down at some rate (if not coming to a standstill and reversing) due to gravity. So some kind of ‘dark energy’ explanation might still be necessary.

      In my understanding, if our finite cosmos is surrounded by infinite others in an infinite eternal multiverse, then in this model it’s gravity itself (not a dark energy) that would cause an accelerating expansion, though there’d be an element of variation to the expansion as the rate of acceleration would be proportional to a collective mass, so, subdivisions of a collective mass, on all scales, accelerate apart at proportionately smaller rates, causing clumping on all scales. Also, greater concentrations of a collective mass in a certain volume should accelerate apart faster, so they become less concentrated and things tend to even out, hence homogeneity (displacing the contrivance of ‘Inflation’ as an explanation) On top of that, the rate of acceleration should additionally be, exponentially proportional to the distance apart things are.

      So even if the (accelerating?) expansion can be caused by gravity, the patterns and variations that may emerge would be very complex and it should take many more years and observations to get the big picture. And we might need more than supernovae type1(a)s as the candles to be sure.

      • MJBridger

        The amount of calculated ‘dark energy'(acceleration) in the visible universe has previously been given a quantity that can account for the observed ‘flatness’. But if it now seems that there is much less, then the flatness could be the evidence for a background infinite, eternal universe, which would be ‘flat’ whatever the density of mass/energy. And if the universe is infinite and eternal (our cosmos/bang surrounded by infinite others) then gravity can become the cause for the expansion. This rate of expansion would be a measure of the distribution of other cosmoses in the nearer part of the surrounding infinite universe.

  2. Robert Cheshire

    A symmetric connection in the lower two indices in the commutator of covariant derivatives, and under the auspices of Einstein’s General Relativity, means that both the curvature and the torsion of spacetime are cancelled out. The false “Swartzchild Metric” is not even attributable to Swartzchild and is false in its conjured conclusions. If the both of the above were true, and there exists very compelling evidence now for that to be so, then there was never even any expansion, let alone accelerated expansion because the above precludes the idea of “point singularity” and therefore; there can be no Big Bang, no Black Holes, no Dark Matter and no String Theory, to cite but a few “knock on” errors. If dogmatic chanting of unchecked, and unsound theory continues, Physics will become an elaborate joke – as with magicians but of lower esteem. This seems harsh, but let’s get real about our invisible, untraceable, radioactively unrecordable phenomena in the cosmos as being much like a matter of faith – also being as the above phenomena – invisible bodies in the sky. The enemy of all science is dogma. “Due diligence” is the only remedy but dogmatic acceptance has been overriding much of that for 100 years.

    • MJBridger

      The Big Bang / expansion of the visible universe does present a problem as to how it started, but your dogma has to be off the scale to deny all the evidence for the Big Bang just because you cannot conceive of how it started. It does not necessarily imply a “point singularity” in particular. The point singularity is an as yet unresolved mathematical/physical problem concerning extreme gravity (but given an explanation of gravity, along with dark matter, the solution may become apparent).

      • Robert Cheshire

        I have been citing the dogma of 100 years and since publication of Einstein’s General Relativity in 1915. As one might imagine, that if ANY errors existed in EGR at a fundamental level, then any theory reliant on erroneous elements of EGR would be highly suspect if not scientifically obsolete. Together with my own cosmological observations, I have been privileged enough to witness the mathematical reportage – via computer checked algebra – of 57 points of error and “knock on” error in EGR. Einstein’s Special Relativity remains much in tact after such diligent scrutiny but unfortunately for those theories I had mentioned before, EGR is proven to be obsolete. So this is not “my dogma” as you put it, but the result of scholarly revision using observation, experiment and computer checked mathematics in these realms. the 21st century has brought more “dissident” scientists into the frame because of the lack of final cohesion in a century old, failed theory that a majority had been dogmatically clinging to without “due diligence”, and simultaneously issuing abuse to any “dissenters” of the party line. The abuse stage is nearly over and especially as more and more new scientists turn back to observation and experimentation, and the deterministic logic found in Baconian science and via Ockhams Razor. The truth is much simpler than we have been led to believe through the 20th century. The fantasies we are left with in the cosmos, have been just that; suppositional and assumptive fantasy. This is what happens when folks can’t determine dogma from revelation because they have never checked for themselves. In this light, Physics has become a mass of obfuscation and more a vested “business” of diminishing repute.

    • MJBridger

      I like your challenge RC but see Einstein’s gravity GR as incomplete rather than erroneous (just as he thought himself). A complete theory will be tied in with a theory of everything that also explains quantum physics, dark matter and the singularity problem.

      • Robert Cheshire

        If EGR purports a symmetric connection in the lower two indices of the matrix associated with the commutator of covariant derivatives in that theory; then I’m afraid the theory will always remain “incomplete” because that “incompleteness” is due to drastic error in not using an antisymmetric connection as required by strict mathematics and concomitant logic – that among a host of other points of error. This particular error cancels the presence of both spacetime torsion and curvature. Can you be happy with that single erroneous pronouncement?

    • Aaron Vee

      Mr Cheshire gets all of his ideas and opinions from a Myron Evans (, who also believes that the Bessler Wheel was a viable energy-source! Whatever is wrong with real physics will self-correct; cranks will never do so.

  3. John C. Polasek

    Dark energy does not exist, as I will demonstrate in a paper I’m about to post on arxiv.
    Remember that neither dark energy nor acceleration have been detected, only an unexpected dimness in the supernovae and a stretching of their lifetimes with red shift, for which I have found a (new)much simpler explanation.
    Dark energy was “found” through the use of complex equations (FLRW) having an imaginary cosmological constant as a free parameter, with a value of 0.76 appearing to explain the dimness.
    Millions of dollars, new telescopes planned, hundreds of papers in the National Science Foundation index (shouldn’t these be published?) and quite a few books on Amazon,all about dark energy, not any of them as far as I can see expressing any doubt. What happened to the scientific boast “Question everything!”
    Dark energy does not seem reasonable (but I believe DE is protected by the intractable equations used in the findings) and in fact, cannot survive against a more fundamental explanation in my paper.

    • MJBridger

      When an apparent phenomenon is labelled, there’s a tendency for the label to displace an explanation. Still, I think the label ‘Dark Energy’ is well known for not yet having a consensus satisfactory explanation.

      • Abed Peerally

        The accelerating expansion of the universe is not possible to explain except by the dark matter/energy complex. An accelerating expansion reverses the trend we saw during the exponential inflation which definitely occurred soon after the origin of the universe. There is no likelihood that there could exist some kind of antigravitation for that would violate the law of conservation of energy. Therefore this work by Sarkar and colleagues and those of Melia and colleagues in 2012 2013 and 2015 constitute very interesting conclusions which we need to take seriously The issue of invisible matter and energy need to be addressed as regards its finality for the good of science.

      • MJBridger

        Abed, Call it dark energy or dark matter but then the mystery remains as to why it should be repulsive rather than gravitationally attractive. If we are in a multi universe though – our cosmos surrounded by infinite others – the answer is simple. It is not a repulsion but a background gravitational attraction; the mass of our cosmos falling out to the infinite mass beyond.

  4. John C. Polasek

    I found out I could not post an article to arxiv without having an endorser. Any volunteers?

  5. Abed to Bridger

    Bridger, the infinite mass beyond hypothesis of what would result in a negative gravitation is not quite an answer. Let me explain it in another much simpler way. The gravitational attraction of Earth is an inverse square relationship with respect to the centre of mass. But normally this gravitation get stronger, in theory, as you approach the centre of mass. The contrary happens at a certain point. That is the centre of mass itself where gravitation is practically 0 so you would be floating in a vacuum theoretically as you would in outer space. The earth mass away from the centre would cancel each other and leave 0 gravitation at the centre, assuming that we have equal masses in all directions.

    • MJBridger

      Abed, yes I am very familiar with the reasoning and the maths that says in an infinite universe the gravity vector from the infinity on any point or mass would be zero, and how indeed could you have a vector that makes a mass expand?
      Newton’s shell theorem is the classic reasoning / the argument that stands in the way of my theory. But the Newtonian approach has gravity working instantly at a distance. With an Ensteinian approach it works out differently, provided you have a multicosmos model (which in itself is supported by relativity) rather than a singular infinite universe. Sorry there isn’t the space to explain and illustrate it here but I have published the theory.

      • Abed to Bridger

        I am actually currently writing like you about infinite universes, just passingly in a book on the origin of our universe, and I have this problem of dark/energy/matter in mind and if the work of Gufanti, Melia and coworkers is generally supported that will be a big blow to the missing mass. When it is argued that dark energy etc have antigravitation property, in my definition of gravity which is very different from the others. I see that antigravitation, if ever it exists, can only be produced by a totally different kind of matter than what we know about in classical matter. As regards the issue of infinite sets of universes, to me this is just a mirage. At least in my concept of the universe there is no possibility to have neighbouring universes. That would make our own universe infinitely unlikely. In other words our universe is a unique entity, in a unique dimension which is its matter, space time and it has no boundary for its expansion is by itself with its spacetime, not into some additional external space for to me that is just an imaginative and speculative possibility. I will be happy to see your paper,

      • MJBridger to Abed

        It may be a matter of taste but to me nothing can exist in isolation, or something cannot come out of nothing, or the universe has to be infinite, as relativity implies.

        I should stress its not antigravity but ‘ordinary gravity’ that would propel an expansion. When the mathematician Friedmann applied GR to an infinite universe he showed Einstein that the universe may collapse or expand (but not in an acceleration). But if an infinite universe expands, only a finite part of it has objects receding at less than the speed of light relative to each other, so the infinite part becomes unreal. If you amend the infinite universe (given a mulitversal possibility) to one of infinite expanding cosmoses, but with the distances between the cosmoses not expanding, then you can have a ‘real’ infinite universe in which there is no overall expansion/loss of density. Now import the Friedmann maths and it will say the expansion of each cosmos should accelerate (and account for an expansion without the need of inflation theory). See ‘the pi universe’.

  6. Derek

    Dark energy has a mass equivalence e=mc2. This mass would exert an attraction rather than promote expansion. Has this been considered?
    I have not seen any discussion though I believe Roger Penrose suggested the problem.

  7. Fulvio Melia’s work has been mentioned a couple of times. He points to the interesting mathematical “coincidence” that the lambda-CDM “Consensus Cosmology” tracks very closely the R_h = c.t cosmology that he advocates. The fact that other data analyses are showing the “coasting cosmology” fits the data, is thus no surprise.

    This seems to imply that cosmologists have created artificial paradoxes for themselves by assuming that the critical density of the observable universe is a one time event in our present day, rather than valid since the beginning. Perhaps research should focus on how the contents of the Universe evolve to keep a flat cosmos all the way back.


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