What is dark matter?

5

Answers


  1. 0 Votes

    Dark matter is a subtance that makes up 25% of the universe.  It remains mysterious and unknown in its exact properties.  Dark matter (along with dark energy) was first discussed as an explanation to why the universe was expanding at an accelerated pace.  Scientists speculate that dark matter may be made up of Massive Compact Halo Objects (MACHOS) or Wealky Interacting Massive Particles (WIMPS). 

    It may help to add that dark matter is not made of antimatter or regular matter, and it does not form black holes.  These have all been ruled out as possibilities.

  2. 0 Votes

    Dark matter is a theoretical, unobserved material that scientists believe is responsible for otherwise unexplainable gravitational phenomena throughout the universe. The dark matter theory explains what is called the “missing mass problem,” where there is a large discrepancy between the observed and computed mass of a galaxy. It is believed that it is either made up of MACHOS (Massive Compact Halo Objects) or WIMPS (Weakly Interacting Massive Particles). MACHOS would be huge objects that are extremely far away and do not reflect enough light (if any) to be seen from Earth, while WIMPS would be too small to be seen. It is unknown what dark matter is composed of, as its existence can only be inferred.

    The link below is a good introduction to the idea of dark matter.

  3. 0 Votes

    There was an article in the BBC last week regarding dark matter; it detailed the controversial Modified Newtonian Dynamics (or MOND) theory, which argues that instead of the elusive dark matter, the missing mass in galaxies is a result of the shifting behavior of gravity. You see, if standard laws of gravity hold true, matter spinning at the edges of galaxies should rotate more slowly than matter spinning closer to the center – just like the outer planets of our solar system orbit the sun more slowly than the inner planets do. However, according to our observations, this doesn’t seem to be the case – matter both at the ends of the spiral arms and closer to the center of our galaxy are spinning at roughly the same rate. In order to compensate for this “flat rotational curve” the idea of dark matter was developed – heaps of unseen matter in a halo around our galaxy, adding the extra mass necessary to explain the flat rotational curve.

    The MOND theory disagrees with this assessment. First proposed by Dr. Mordehai Milgrom in 1983, the MOND theory argues that the effects of gravity itself changes in galaxies where its pull is low – in low mass, gaseous galaxies for instance. The theory was recently bolstered in part by the work of Dr. Stacey McGaugh, whose use of the MOND theory in studying  “gassy galaxies” found that the theory “neatly predicts the relation between the galaxies’ masses with their rotation speed“. Still, the predictions fall apart when extrapolated to larger masses, like galaxy clusters. The article was definitely worth a read if you’re interested in dark matter, it’s linked below.

    An artist’s conception of a dark matter halo:

  4. 0 Votes

    Uniontera number 11-1, hope it helps. This is your so-called dark E&M.

    Existence is the time expressed by light itself. http://www.youtube.com/watch?v=AN1jTwHUC7E

    1. When same times met … Arrow A (Cause of Laser / Origin of Death / Reason of Chemical reaction)
    2. When different times met … Arrow B (This is your so-called “Gravity” / Cause of Higgs boson / Origin of Life / Reason of Biological reaction)
    3. The rose line is the beginning light. (result from Genesis 1:3)
    4. The existence of different time. (result from relativity of light)
    5. 2 dimension is not a space. (result from 2-axis, math)
    6. Universe came from nothing. (result from No.5 / cf. Playing with bubbles)
    6-1. A barrier[posititon] exist between the inner and outer bubbles. But universe do not have that barrier. (Cause of Inertia / Reason of Sun / Position of Antimatter / Origin of Fire / cf. Expansion, Conservation of parity, Time-reversal invariance)
    6-2. Nothing is not a no existence. No existence is a zero dimension. There is two zero dimension. One has a position. The other doesn’t have a position. These different positions were connected by something. That “something” is not a what but a way. (Cause of Light / cf. Ether)
    7. Progress / Event / Probability is a time. (This is my trinity.)
    8. Wave-particle duality of light, creation & evolution, uncertainty principle, etc. (result from No.7)
    9. Coalescing of different times. (Cause of Rotation & Spin / Equator has plenty of time. / Origin of Colour / Reason of Reflection / cf. Strong interaction)
    10. Your so-called “Black hole” is a wholly condensed time. (cf. Kerr spacetime)
    11. The reason of your so-called “Magnetic field”. (result from step3 and 4)
    11-1. The reason of your so-called “Dark matter”. (result from step3 to 4 / Energy-Mass duality / cf. Dark energy “step4 to 3”)
    12. The reason of your so-called “Electric field”. (result from the crack of time / Same time’s crack is a different time’s connection. / Cause of Static electricity)
    13. Your so-called “Space” is a crack of time. (result from No.12 / Cause of Lightning / Reason of Refraction / cf. Weak interaction)
    13-1. The reason of your so-called “Capture & Decay”. (result from No.13’s crack of time / cf. Violation of time-reversal invariance)
    13-2. The reason of No.6-2’s “position & none position”. (result from No13-1’s “capture & decay”)
    13-3. The reason of No.13’s space. (result from No.13-2’s “position & none position” / cf. Noneconservation of parity)
    14. Boundary is a crack of space. (result from No.13 / Same space’s crack is a different time’s contact. / Cause of Superfluid / cf. Fractal)
    15. Boundary is nothing. Your so-called “Hole” is a boundary itself. Also, nothing is K=0 temperature. (result from No.14 / cf. Calabi-Yau, Hilbert space)
    16. This is a wall of your so-called “Fire”. (result from No.15) – copyright ⓒ uniontera

    Our nonsense has come from one time. Uniontera is a key.

    English is not my first language, sorry!

    If it is difficult to understand, just remember & enjoy “Hand touching everything is a time”. This is the only one result of uniontera.

  5. 0 Votes

    Uniontera number 11-1, hope it helps. This is your so-called dark E&M.

    Existence is the time expressed by light itself. http://www.youtube.com/watch?v=AN1jTwHUC7E

    1. When same times met … Arrow A (Cause of Laser / Origin of Death / Reason of Chemical reaction)
    2. When different times met … Arrow B (This is your so-called “Gravity” / Cause of Higgs boson / Origin of Life / Reason of Biological reaction)
    3. The rose line is the beginning light. (result from Genesis 1:3)
    4. The existence of different time. (result from relativity of light)
    5. 2 dimension is not a space. (result from 2-axis, math)
    6. Universe came from nothing. (result from No.5 / cf. Playing with bubbles)
    6-1. A barrier[posititon] exist between the inner and outer bubbles. But universe do not have that barrier. (Cause of Inertia / Reason of Sun / Position of Antimatter / Origin of Fire / cf. Expansion, Conservation of parity, Time-reversal invariance)
    6-2. Nothing is not a no existence. No existence is a zero dimension. There is two zero dimension. One has a position. The other doesn’t have a position. These different positions were connected by something. That “something” is not a what but a way. (Cause of Light / cf. Ether)
    7. Progress / Event / Probability is a time. (This is my trinity.)
    8. Wave-particle duality of light, creation & evolution, uncertainty principle, etc. (result from No.7)
    9. Coalescing of different times. (Cause of Rotation & Spin / Equator has plenty of time. / Origin of Colour / Reason of Reflection / cf. Strong interaction)
    10. Your so-called “Black hole” is a wholly condensed time. (cf. Kerr spacetime)
    11. The reason of your so-called “Magnetic field”. (result from step3 and 4)
    11-1. The reason of your so-called “Dark matter”. (result from step3 to 4 / Energy-Mass duality / cf. Dark energy “step4 to 3”)
    12. The reason of your so-called “Electric field”. (result from the crack of time / Same time’s crack is a different time’s connection. / Cause of Static electricity)
    13. Your so-called “Space” is a crack of time. (result from No.12 / Cause of Lightning / Reason of Refraction / cf. Weak interaction)
    13-1. The reason of your so-called “Capture & Decay”. (result from No.13’s crack of time / cf. Violation of time-reversal invariance)
    13-2. The reason of No.6-2’s “position & none position”. (result from No13-1’s “capture & decay”)
    13-3. The reason of No.13’s space. (result from No.13-2’s “position & none position” / cf. Noneconservation of parity)
    14. Boundary is a crack of space. (result from No.13 / Same space’s crack is a different time’s contact. / Cause of Superfluid / cf. Fractal)
    15. Boundary is nothing. Your so-called “Hole” is a boundary itself. Also, nothing is K=0 temperature. (result from No.14 / cf. Calabi-Yau, Hilbert space)
    16. This is a wall of your so-called “Fire”. (result from No.15) – copyright ⓒ uniontera

    Our nonsense has come from one time. Uniontera is a key.

    English is not my first language, sorry!

    If it is difficult to understand, just remember & enjoy “Hand touching everything is a time”. This is the only one result of uniontera.

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