The Universe Revealed is my attempt to discuss more thoroughly the main questions that we humans should ask about our existence, our universe and our place in it. These are mostly my thoughts on science, religion and philosophy as it applies to the...
An article on the Inside Science site reports about observations that could explain how galaxies rotate without including dark matter.
Astrophysicists have used dark matter to explain the confusing way that stars rotate around the center of galaxies. In the solar system planets closer to the sun travel faster than those further out, which is what should happen according to Newton's laws of motion. This is not true about stars in a galaxy. Stars further out from the center travel as fast at those near the center. Of course the stars near the center orbit around the core, which contains a supermassive black hole, in less time than those further out. In any event, dark matter dispersed among the stars was used to explain this phenomenon.
New research that examined 153 galaxies indicated that the anomaly could be explained by determining where stars were located among gas clouds, which would indicate that dark matter might be more like normal matter. This comes from Case Western Reserve University in Cleveland, Ohio. The study, examining red giant stars, shows that this strange pattern is observable in all sorts of galaxies.
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One way to explain this is to suggest that Einstein wasn't quite correct about his concept of gravity in his general theory of relativity. What is proposed is a Modified Newtonian Dynamics (MOND), which was proposed 30 years ago.
As expected this new theory has caused arguments among physicists and astronomers. Some of the ideas about dark matter include that dark matter behaves like a superfuid that flows without viscosity. Then there is the ides that dark matter particles line up in a gravitational field as if they were like iron filing in a magnetic field.
So far no evidence of a dark matter particle has been discovered at the Large Hadron Collider. However, a recently observed strange gamma ray signal from the center of our galaxy might be from the collision of two WIMP (weakly interactive massive particles) particles could have produced the signal picked up by NASA's Fermi Gamma-ray Space Telescope.
My take on this is that it's possible but not necessarily right. We need to discover what dark matter is, which would prove it does exist. Or not! The same could be said about dark energy. We just don't know what these 'dark' things are.
