Are There Viable Alternatives to Dark Matter in Explaining Galactic Motion?

[drag]

Greetings !

I wonder if we really need to pursue just the dark matter
direction to explain why galaxies turn the way they do and
the whole cosmology part about the form of Universal space-time.

Has there been an attempt to explain the motion
of galaxies by adding another Universal law or purhaps
altering the law of Gravity for larger scales (in a way
partially similar to what Einstein attempted to justify
a supposedly stable Universe) ? If so (talking about an
extension of Gravity), has there been a consistent pattern
observed - a similar connection between the normal mass of
the galaxy and the estimated required mass of the dark matter ?

In addition, could such an assumption experience difficulties
or alternativly help solve some other cosmological puzzles ?

Thanks !

Live long and prosper.

 

[Labguy]

A good and understandable explanation for most needs starts Here:

http://snap.lbl.gov/brochure/foreword.html

 

[mathman]

There is an alternate approach called MOND (modified Newtonian dynamics) proposed by Milgrom along the lines you suggest. It was written up in a recent issue of Scientific American. The major problem with the approach is that it is rather ad hoc, and difficult to test. I don't know if Milgrom and people working on that idea have come up with some test to distinguish it from non-baryonic matter. Some dark matter is baryonic, but most of it is not.

 

[drag]

Greetings !

I just read a short stroy in a paper today mentioning
Milgrom and the two different approaches to the problem.
Is seems that recent surveys and observation of the dynamics
of settelite galaxies (smaller galaxies orbiting larger
galaxies) are supportive of the Dark Matter hypothesys and
do not favour the alteration of the law of Gravity possibility.

However, the short story that I read did not mention any more
specifics or technical info, so I'd appreciate relevant input.

Thanks !

Live long and prosper.