On black holes and dark matter

[Bamz4l]

what kind of galaxy is the milky way, Einstein?

[Lojik]

Originally Posted by Bamz4l [You must be logged in to view images. Log in or Register.]

what kind of galaxy is the milky way, Einstein?

S3?

[leewong]

Dark matter is just like normal matter but it neither emits nor absorbs light (electromagnetic radiation) or it doesnt absorb enough light to be detected easily. Dark matter can include non-luminous gases, planets, objects condense by black holes, and just about ANYTHING else we cannot detect with electromagnetic radiation. It is only detectable by means of gravitational lensing or other gravitational effects on non-baryonic matter (ie a planet orbiting a star and causing that star to appear to wobble or pulse). There is nothing special about dark matter and it does NOT hold our universe together any more than regular matter does. Dark matter is only a name for matter we cannot detect with light (electromagnetic radiation).

BTW, the universe is expanding and there isnt enough gravity in 3 universes to even come close to slowing it down. What causes this expansion? Dark energy. What causes dark energy? Virtual particles. Virtual particles are constantly popping into and out of existence throughout the universe. The interaction (energy exchanged) between these virtual particles is what we call "dark energy". The virtual particles repel one another (for lack of better terminology) and give rise to the expanding universe. These forces put gravity to shame and it is why the universe does not collapse in on itself. In trillions of years the universe will have expanded so far that even atoms will be ripped apart. This is known as "the big rip"....look it up.

It would be nice if people took the time to understand what scientists claim rather than coming up with half-baked theories.

[leewong]

Gravity is simply a curve in space created by matter (even dark matter). Dark matter IS NOT gravity any more than matter is gravity. When something has mass it creates a "dent" in space. Other objects with mass (if close enough) will feel this "dent" and respond accordingly.

Think of it like being underwater. Water is pressing in on you much in the same way space presses around mass. The difference being that space is curved/dented by mass and that in turn can effect other objects. Any object close enough will tend to roll toward the "dent".