You are here:

Astrophysics/Black holes

Advertisement


Question
There are so many black holes in this Universe, each swallowing so much matter, swallowing black holes themselves, but still the Universe is expanding. What is it that makes it able to expand even after all the matter that is being swallowed down the black holes all over the galaxies? How can it still continues to expand when with such a large amount of black holes, and considering their extreme gravitational force, it should be contracting?
One more thing, are black holes able to affect the dark matter like they affect matter?

Answer
The matter in the universe has momentum which makes it spread out, and the black holes lack the strength (they're really only that strong locally, gravitation is by FAR the weakest of the four fundamental forces) to stop the expansion.  Aside from that, we know that the universe is accelerating as it expands.  It's difficult to observe for now, but it's definitely there.  The nature of what is making it accelerate (called "dark energy" by physicists because it does not have a noticeable interaction via the electromagnetic force responsible for light) is one of the biggest mysteries in science right now.

Astrophysics

All Answers


Answers by Expert:


Ask Experts

Volunteer


Dr. Stephen O. Nelson

Expertise

Fusion, solar flares, cosmic rays, radiation in space, and stellar physics questions. Generally, nuclear-related astrophysics, but I can usually point you in the right direction if it's not nuclear-related or if it's nuclear but not astrophysics.

Experience

Just moved from being a physics professor at the University of Texas of the Permian Basin into government work. Doctoral dissertation was on a reaction in CNO-cycle fusion, worked in gamma-ray astronomy in the space science division of the naval research laboratory in the high-energy space environment branch.

Organizations
Government work as a physical scientist with a nuclear focus.

Education/Credentials
Ph.D. in physics, research was on nuclear fusion reactions important in stellar fusion, further work on space telescope technology.

©2016 About.com. All rights reserved.