Unsolved Problems in Theoretical Physics and Astrophysics

[Stratosphere]

I have been wondering what some of the big problems in theoretical physics and astrophysics are. Through some research I have not been able to find a whole lot of them, I am starting to think that this means we have a good grasp on understanding the universe but then I realize that this can't possible be. So I am looking to you guys for some things that I may not have been able to find from these websites:

http://en.wikipedia.org/wiki/Unsolved_problems_in_physics

http://july.fixedreference.org/en/20040724/wikipedia/Unsolved_problems_in_physics

 

[mathman]

Both lists look like they cover a lot of ground. Why don't you think they are adequate? For starters dark matter and dark energy add up to about 95% of the universe, but what they are is essentially unknown.

 

[Stratosphere]

Yes but it seems to me that dark matter and energy aren’t theoretical problems they are more observational. And if these are the only problems left doesn't that mean that we have a near complete understanding of the universe?

 

[Buckleymanor]

Yes but it seems to me that dark matter and energy aren’t theoretical problems they more observational.

Well it must be turtles all the way down

 

[0xDEADBEEF]

I for my part find these dark fudge factors highly mysterious too

 

[mathman]

Yes but it seems to me that dark matter and energy aren’t theoretical problems they are more observational. And if these are the only problems left doesn't that mean that we have a near complete understanding of the universe?

These things have been observed but there is no theory to describe them. I would call that a theoretical problem.

 

[yrreg]

Excuse me, are there pieces of empirical evidence for dark matter and dark energy?



Yrreg

 

[mathman]

The evidence for dark matter is the amount of matter needed to hold galaxies and galactic clusters together is much greater than what can be accounted for by ordinary matter (stars, gas clouds, brown dwarfs, etc.), which is about 1/5 of what is needed.

The evidence for dark energy is the observation that the expansion of the universe is speeding up, rather than slowing down (which is what would be expected from gravity alone).

 

[phyzguy]

The evidence for dark matter is the amount of matter needed to hold galaxies and galactic clusters together is much greater than what can be accounted for by ordinary matter (stars, gas clouds, brown dwarfs, etc.), which is about 1/5 of what is needed.

In addition to the above evidence for dark matter from the motion of stars in galaxies and galaxies in clusters, dark matter is also needed to explain the observations of the Cosmic Microwave Background (CMB), and the growth of structure in the early universe. All three of these different observations also point to roughly the same amount of dark matter.