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Universe may face a darker future

Cosmologists use galaxies observed by the Sloan Digital Sky Survey to study the nature of dark energy – CREDIT: Sloan Digital Sky Survey

Cosmologists use galaxies observed by the Sloan Digital Sky Survey to study the nature of dark energy – CREDIT: Sloan Digital Sky Survey

New research offers a novel insight into the nature of dark matter and dark energy and what the future of our Universe might be.

Researchers in Portsmouth and Rome have found hints that dark matter, the cosmic scaffolding on which our Universe is built, is being slowly erased, swallowed up by dark energy.

The findings appear in the journal Physical Review Letters, published by the American Physical Society. In the journal cosmologists at the Universities of Portsmouth and Rome, argue that the latest astronomical data favours a dark energy that grows as it interacts with dark matter, and this appears to be slowing the growth of structure in the cosmos.

Professor David Wands, Director of Portsmouth’s Institute of Cosmology and Gravitation, is one of the research team.

He said: “This study is about the fundamental properties of space-time. On a cosmic scale, this is about our Universe and its fate.

“If the dark energy is growing and dark matter is evaporating we will end up with a big, empty, boring Universe with almost nothing in it.

“Dark matter provides a framework for structures to grow in the Universe. The galaxies we see are built on that scaffolding and what we are seeing here, in these findings, suggests that dark matter is evaporating, slowing that growth of structure.”

Cosmology underwent a paradigm shift in 1998 when researchers announced that the rate at which the Universe was expanding was accelerating. The idea of a constant dark energy throughout space-time (the “cosmological constant”) became the standard model of cosmology, but now the Portsmouth and Rome researchers believe they have found a better description, including energy transfer between dark energy and dark matter.

Italian research students Valentina Salvatelli and Najla Said

Italian research students Valentina Salvatelli and Najla Said

Research students Valentina Salvatelli and Najla Said from the University of Rome worked in Portsmouth with Dr Marco Bruni and Professor Wands, and with Professor Alessandro Melchiorri in Rome. They examined data from a number of astronomical surveys, including the Sloan Digital Sky Survey, and used the growth of structure revealed by these surveys to test different models of dark energy.

Professor Wands said: “Valentina and Najla spent several months here over the summer looking at the consequences of the latest observations. Much more data is available now than was available in 1998 and it appears that the standard model is no longer sufficient to describe all of the data. We think we’ve found a better model of dark energy.

“Since the late 1990s astronomers have been convinced that something is causing the expansion of our Universe to accelerate. The simplest explanation was that empty space – the vacuum – had an energy density that was a cosmological constant. However there is growing evidence that this simple model cannot explain the full range of astronomical data researchers now have access to; in particular the growth of cosmic structure, galaxies and clusters of galaxies, seems to be slower than expected.”

Professor Dragan Huterer,of the University of Michigan, has read the research and said scientists need to take notice of the findings.

He said: “The paper does look very interesting. Any time there is a new development in the dark energy sector we need to take notice since so little is understood about it. I would not say, however, that I am surprised at the results, that they come out different than in the simplest model with no interactions. We’ve known for some months now that there is some problem in all data fitting perfectly to the standard simplest model.”

11 total comments on this postSubmit yours
  1. Can you share a link to the paper?

  2. In 1994 I recorded in a painting a theory of the universe according to which Gravity should cause an accelerating expansion of the cosmos (falling out into a greater/infinite universe). That included some explanation for the clumping of matter as the cosmos expands and some dark matter effects. Around 2000 I added another theory for dark matter observations which would explain its gravity-only interactiveness, its quantity relative to ordinary matter and its part in the structure of matter and formation of galaxies. According to this theory dark matter(s) in extreme gravity may reform eventually as ordinary matter.

  3. Valentina, I enjoyed reading your article about dark matter and dark energy. Have you considered the data from the Planck satellite showing the relative concentration of matter to energy has changed over time. There was much more matter relative to energy in the distant past than there is today according to the Planck satellite data. This data is consistent with the conclusion in your article. This data and your data can be used as an alternative method of dating the age of the universe. If you would like to see a paper on this subject, I can send it to you. Contact me at my e-mail address:

  4. In an outgrowth of my work on a ‘what ‘if’ basis for the quantisation of the frequency of electromagnetic eadiation, i have developed a model of the universe in which the ratio of the dark energy density to the ground state energy density is very close to the trace of the spatial part of the stress-energy tensor for a perfect fluid and that the ratio of the cosmological constant (cosmological term is a more appropriate descriptor) to the dark energy density equalsl -K/3, where K is Einstein’s gravitational constant.
    In addition, it is shown that a possible candidate for Dark matter is composed, not of a new particle, but from existing particles formed into a structure which is charge neutral, has no electrons, hence no chemistry, emits no photons, is thermally inert and at a temperature of absolute zero; the icing on this particular cake is that the structure has a mass equivalent of slightly less than 12 protons.

  5. If dark energy is the expansion of space, this sounds logical, especially if dark matter is the result of the weak interaction, it would appear to be just one of the first to undergo the this effect. With that said it would appear; as if the strong interaction may just be the last to undergo this dilution of space. However there are other possibilities which the confinement of the strong force has in store, that being the replication of baryons through the strong force energy supplied by the gluons displacement production of virtual anti particles. In which case matter would be increasing. This idea set in the environment of the expansion would bring into existence a much greater universe, than we have now. Just think about it.

  6. I would like to edit my post above. In the sentence ” However there are other possibilities which the confinement of the strong force has in store, that being the replication of baryons through the strong force energy supplied by the gluons displacement production of virtual anti particles. “, I wish to substitute the word “complementary” in the place of “anti” It reflects a much better picture of this process which I suggest, ; after several other lesser conversions, converts dark energy into mass through the production of quarks and thereby production of baryons. Thank you.

  7. Recently a study has suggested that dark matter can “fall” into black holes (what a fitting marriage of namesakes …) and “augment” them. To me this begs the question why e.g. our Earth does not “grow” (gravitationally) by “swallowing” dark matter (or dark matter incorporating itself into it). Following the development of the dark matter/dark energy paradigm from almost its beginning (remembering dark matter caused quite a stir when it was, er, well not discovered but surmised) I still am not convinced these are “entities” but maybe rather “properties” pertaining to space and time and the “brighter” matter and energy that we can “see” (kind of). I sometimes have a feeling that we are at the brink of a discovery like when more and more “spheroids” and aberrations appeared in the geocentric model of planet observations until … all got reconciled via a new paradigm – heliocentric model.

  8. Valentina, associates thank you for placing your effort into this subject.

  9. A really impressive result of the research, in spite of the absence of an underlying theoretical description of the mechanism. Nevertheless, I wonder a bit about the remark of professor Wands (the energy density of empty space isn’t a cosmological constant). Because in the all-inclusive quantum field theory there is no “domain wall” between empty space and physical phenomena. So dark matter seems to be a local concentration of deforming: the condition of space just prior to the higgs mechanism (the local transfer of energy from the scalar field to the vector field).

  10. At the moment researchers are using a high definition cam to observe the expansion of the universe to give a value to the cosmological constant. Therefore they could be able to verify the big-rip-theory and calculate the remaining time.
    Since we have not observed this “constant” before it has more than one possible value. Measuring it would end this quantum state. Since we are talking about a fundamental force of the universe, that can also be seen as a counter part to gravity, it is hard to tell the consequences
    Also I am really worried, that not a single scientist seems to see ethical flaws in calculating the end of the universe.

    Can someone please share her or his thoughts on this?!

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