View Full Version : Dark matter/energy

2005-Mar-15, 09:21 PM
Now, I thought that dark matter is just normal matter that doesn't shine. Like brown dwarves and cold white dwarves and the like...
And dark energy is the weird stuff that no one can really understand....

Is that correct?

2005-Mar-15, 09:30 PM
It depends. Usually by "dark matter" a physicist means "nonbaryonic dark matter", i.e., weird stuff that has gravitational force but isn't the atoms and such we are used to. However, it can also refer to any matter that we can't see - Mario Livio at my Smithsonian session last Saturday stated that the planet Neptune was the first example of dark matter in history, since its existence was inferred from its gravitational effects before it was ever observed.