I think dark matter and energy are an important new aspect of science and should have a new thread on them.

One thing I would point out about Dark energy and Dark matter is that they are opposite in quality from each other in many respects;

Dark energy causes the universe to expand and counteracts the gravity of the galaxies; it also seems to work evenly throughout space - some people even suspect it works more strongly where there is no matter;

whereas dark matter has normal gravity, and is concentrated in galaxies.

In common, both are invisible and intangible as far as anyone can tell at the moment.

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