What’s the (dark) matter?

NASA, ESA, M. J. Jee and H. Ford et al. (Johns Hopkins Univ.)

What sort of stuff makes up our universe? The question is almost a throwback to the ancient Greeks, who first coined the idea that everything is composed of tiny units called atoms, or the later erroneous view that an “ether” fills all of space.

And here we sit, asking the question anew. On March midnights, a vast emptyish zone fills the southern sky between the constellations of Leo and Virgo. The identity crisis manifests in this area, found by following the Big Dipper’s arc in an enormous looping curve toward the blue star Spica. This region is home to the nearest large cluster of galaxies, the Virgo group.

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Virgo galaxies sit about 60 million light-years away, which is why there’s no trace of them to the naked eye. Thousands of cities of suns lurk here, and show themselves through backyard telescopes as smudgy blobs peppering the Leo/Virgo boundary. Each has billions of stars. It’s the Times Square, the Main Street of our part of the universe.

The problem is that each galaxy moves so fast that it should easily escape the gravitational clutches of the group as a whole. The galaxy cluster should have dissipated long ago, like a crowd dispersed by the police. It shouldn’t be there at all.

While we’re at it, neither should our own little knot of 30 galaxies that lies at the distant fringes of Virgo’s influence. Nor should any of the other more distant galaxy clusters. Either gravity is oddly weak at great distances, or some unseen glue is holding all these galaxies together. This is the “dark matter” that everyone’s searching for.

To supply this much gravitational attraction, there’s got to be six times more stuff in these galaxies than meets the eye. They can’t be stars, because we’d see stars. They can’t be dusty nebulae, because they’d block the light of the stars. They can’t be black holes, because that would influence motion. The dark area of Virgo, so initially uninteresting this month, proves a metaphor for one of the greatest celestial mysteries: If 85 percent of the cosmos is made of unknown stuff, then we (Sun, Earth and its tormented inhabitants) are an odd, atypical cosmic item – a minority substance in the cosmic census.

Everyone has a different guess. Maybe it will really come down to some fundamentally strange aspect of gravity. But recent evidence indicates that some types of subatomic neutrinos may have a bit of mass. Even if so, there wouldn’t be enough of them to add up to all the missing gravity. Maybe there are a nonillion baseballs out there, or comet nuclei. Every idea has problems. Many can supply some of the dark matter, but not all. It has to be something we cannot see, yet which exerts a gravitational pull.

If the dark matter is an entirely new form of material, unlike the baryonic matter that comprises our bodies and our planet, then we have been demoted once again, big-time. Long ago we were displaced from our assumed position at the center of the universe, then nudged from the center of our galaxy. Now it may be that we are made of material that is not even representative of most of the universe.

If you’ve been feeling odd, maybe that’s the reason.

Want to know more? To read Bob’s previous columns, visit our Almanac Weekly website at HudsonValleyOne.com. Check out Bob’s podcast, Astounding Universe, co-hosted by Pulse of the Planet’s Jim Metzner.

There are 3 comments

  1. mpc755

    Dark matter is a supersolid that fills ’empty’ space, strongly interacts with ordinary matter and is displaced by ordinary matter. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity.

    The supersolid dark matter displaced by a galaxy pushes back, causing the stars in the outer arms of the galaxy to orbit the galactic center at the rate in which they do.

    Displaced supersolid dark matter is curved spacetime.

    In the Bullet Cluster collision the dark matter has not separated from the ordinary matter. The collision is analogous to two boats that collide, the boats slow down and their bow waves continue to propagate. The water has not separated from the boats, the bow waves have. In the Bullet Cluster collision the galaxy’s associated dark matter displacement waves have separated from the colliding galaxies, causing the light to lense as it passes through the waves.

  2. Scott Van Note

    The Theory of Every Thing:
    Particle science for the masses. Simple as arithmetic.
    1D particle, spinning 1D axis.
    2D Gravity, 90 degree twist spins 1D into disc particle, creates a chaotic field by travelling in circles.
    3D Photon, 90 degree twist into gyro particle, travels straight *across* a chaotic field, making circles
    4D Electron, gyro with one too many twist shells, travels straight in an ordered field ’cause it turns back into a gyro.
    5D spherical mass of spinning spins, doesn’t travel.

    Time is the exchange of motion (entropy) from mass to gravity, 0D spread through the chaotic field.
    Gravity is entropy in one direction in that field. High motion to low.
    Changing your entropy rate environment changes the size of the path of photons (speed of light ratio), denser chaos makes tighter circles. Circles = wavelength.
    First row of the periodic table is Gravity, Photon, Electron. Second is Hydrogen, Deuterium, Helium

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