At this link:
there is a wiki-consented (whatever it means) about problems still withouth solution in today's physics.
Maybe the list can generate controversies and also help to create some new threads. I found a couple of them rather
amusing, because if you do a proper research, some of them are considered solved by many. It is, maybe, a good
sample that Wikipedia is a biased tool to be considered reliable as a source of information.
The list is sumarized as:
1. General physics/quantum physics (9)
2. Cosmology and general relativity (12)
3. Quantum gravity (6)
4. High-energy physics/particle physics (14)
5. Astronomy and astrophysics (17)
6. Nuclear physics (2)
7. Atomic, molecular and optical physics (2)
8. Classical mechanics (1)
9. Condensed matter physics (11)
10. Plasma physics (5)
11. Biophysics (5)
The list gives a total of 84 unsolved problems at physics.
I'm shure (intuition) that many problems are missing the list and that, perhaps, there are overlapping areas
which create more problems due to such overlap.
In particular, I found some of them interesting, as they can have an open debate here. Other problems are
too specific to discuss here, and that would require a high number of participants.
I quote here some which I considered suitable for this forum:
- Interpretation of quantum mechanics: Question the capability of QM to describe reality,due to its statistical nature sensitive to human observation, the violation of casualty and its apparent "violation" of human logic.
- Problem of time: Question the dual interpretation of the flow of time as relative in themacrocosmos and absolute at quantum level.
- Size of universe: Even when assume that an observable universe is real and spans in a sphere of 93 Gyl (which, for me, is a problem itself), question the real size of the universe.This one has to be merged with another in the list: Shape of the Universe.
- Magnetic monopoles: Question the current existence of magnetic monopoles carriers.
- Proton radius puzzle: Question the definition of electric charge radius versus thegluonic charge radius.
- Supernovae: Question the mechanism by which an implosion of a dying star becames an explosion.
- Sonoluminescence: Question the transformation of acoustic energy into light bubbles of high energy.
- Coronal heating problem: Question the huge difference in temperature between the Sun's corona and its surface.
I remarked, in red, the one that I'd like to discuss. I have to make an effort stopping myself to choose the first on the list. This
would be highly controversial and hurt some feelings.
Finally, I wanted to say that the problems which are NOT LISTED make me think: How come this one is not in there?