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Intergalactic Missing Mass Missing Again

Ponca City, We Love You writes "Researchers at the University Of Alabama In Huntsville have discovered that some x-rays thought to come from intergalactic clouds of 'warm' gas are instead probably caused by lightweight electrons — leaving the mass of the universe as much as ten to 20 percent lighter (in terms of its ordinary matter) than previously calculated. In 2002 the same team reported finding large amounts of extra 'soft' (relatively low-energy) x-rays coming from the vast spaces in the middle of galaxy clusters. Their cumulative mass was thought to account for as much as ten percent of the mass and gravity needed to hold together galaxies, galaxy clusters, and perhaps the universe itself. When the team looked at data from a galaxy cluster in the southern sky, however, they found that energy from those additional soft x-rays doesn't look like it should. 'The best, most logical explanation seems to be that a large fraction of the energy comes from electrons smashing into photons instead of from warm atoms and ions, which would have recognizable spectral emission lines,' said Dr. Max Bonamente. The work was published Oct. 20 in the Astrophysical Journal."

8 of 171 comments (clear)

  1. Intergalatic? by Anonymous Coward · · Score: 0, Insightful

    Intergalatic? Say what?

  2. uh huh... by djupedal · · Score: 2, Insightful

    The best, most logical explanation seems to be that a large fraction of the current theories put out are similar to the remaining fractions in that they are all delivered out the little brown holes of out-of-control modern astro-theoreticians.

  3. Bias in Physics? by MOBE2001 · · Score: 1, Insightful

    But we 1/r^2 is a good approximation for any gravitational fields near us.

    Yes, 1/r^2 it works pretty well for relatively short distances but it may not be so for long distances. Which is the reason that some physicists don't think there is any missing mass (dark matter) at all and that both GR and Newtonian physics may need to be revised (GR uses Newton's G). This would create all sorts of problems because it would also bring other matters into question such as the supposed accelerated expansion of the universe. The Einstein fanatics and the Big Bang proponents refuse to consider it as a possibility (a lot of careers depend on Big Bang and Esintein being right). Einstein is a demigod in some circles and his wisdom must not be questioned. As a result little funding is allocated for research in this area. That's too bad. We are probably missing some very exciting physics in the process.

    1. Re:Bias in Physics? by 644bd346996 · · Score: 3, Insightful

      Do you really expect language like that to cause somebody to re-evaluate some of the most well-verified physical laws ever postulated?

      "Einstein fanatics"?! "demigod"?! You sound like a crackpot UFO conspiracy theorist. If you think there are flaws with the current models, the only acceptable way to address those concerns is with science. Not ad-hominem attacks against people who are demonstrably smarter and more polite than you.

    2. Re:Bias in Physics? by tm2b · · Score: 4, Insightful

      He might be a crackpot, but the idea isn't. Google on MOND.

      What's easier to believe - that there's a ton of missing mass out there as "Dark Matter" - something that we have no direct evidence for - or that gravity works differently on large scales than a smoothe 1/r^2 at all distances - and works exactly in the way that we observe? Remember that every time that we've had a strong classical theory replaced by something else, it's been at the extremes of our observation - the very fast for special relativity (which reduces to newtonian motion at lower speeds) and the very small for quantum mechanics. We know we're not getting something right on the large scale, and we know that our picture of gravity is incomplete, as we don't have a good quantum gravitational model.

      I don't know, honestly - but it's clear that there's something we don't understand and I think that our human-scale intuition is not well suited for figuring out what explanation is more likely, just as QM and SR aren't very intuitive. Right now, we've got competing models but neither is very satisfactory without more data.

      --
      "It is our blasphemy which has made us great, and will sustain us, and which the gods secretly admire in us." - Zelazny
    3. Re:Bias in Physics? by Nazlfrag · · Score: 4, Insightful

      ...they are a bunch of sharks circling information, just waiting for that first bit of blood that suggests a hole in some established theory.

      Trying to poke holes in in established theories (also known as conducting experiments and analysing empirical data) is more properly called the scientific method. You make it sound like a bad thing, and that ivory tower guardians of cryptic scrolls are the true scientists. You have it all backwards. Theories shouldn't need propping up, they should stand on their own, and especially stand up to repeated scrutiny and analysis. If we failed to poke holes in established methodology there would be no Newton, no Einstein, no progress to speak of.

  4. An intelligent universe? by bradbury · · Score: 1, Insightful

    The puzzle to explain the missing mass may well fail until physicists, whose explanations depend upon a "dead" universe, evolves to encompass the fact that the universe may well have made a "dead" to "live" transition, and therefore a "physics controlled" vs. "intelligence controlled" transition sometime a few billion, but perhaps as much as 6-8 billion years ago. This is documented by Lineweaver's group in dealing with the fact that most of the Earths in our Galaxy are *older* than our own. We are the latecomers. Until the physicists wake up to this fact everything they are spouting is suspect.

    Until physicists and astronomers incorporate ideas such as Dyson Shells or Matrioshka Brains into their thinking (and seek to prove or disprove them) then all of the speculation about dark matter is just yada yada yada. The dark matter can easily be explained by Matrioshka Brains who have left their galaxies.

    The universe has intelligence in it (we being the case in point). Unless theories about the evolution of the universe incorporate theories about the evolution of intelligence and civilizations they are clearly missing part of the equation.

    1. Re:An intelligent universe? by bradbury · · Score: 2, Insightful

      I would be inclined to agree. Spitzer isn't really equipped to study the really interesting (longer) IR wavelengths. Nor is SOFIA. Unfortunately there doesn't seem to be a strong interest in an IR survey telescope. Perhaps a telescope on the far side of the moon would be a good idea but it seems likely that will be a decade or more away.