List of unsolved problems in physics

Wikipedia has some interesting lists, including this one of a more general list of unsolved problems across many fields: https://en.wikipedia.org/wiki/Lists_of_unsolved_problems

The one (listed under other problems) which always struck me since the first time I heard it: "How does the quantum description of reality, which includes elements such as the superposition of states and wavefunction collapse or quantum decoherence, give rise to the reality we perceive? " I still vividly remember the first time I heard the "collapse of the wavefunction" and openly challenged our poor Solid-state electronics professor - it led to a looong discussion at the end of…

Some of these are not problems so much as they are proposed solutions to problems: > Dark flow: Is a non-spherically symmetric gravitational pull from outside the observable universe responsible for some of the observed motion of large objects such as galactic clusters in the universe? I'd like separate lists of the problems (observations that don't fit understanding) and proposed solutions (Dark matter, Dark flow, etc).

https://news.ycombinator.com/item?id=12282932