List of unsolved problems in physics

The following is a list of notable unsolved problems grouped into broad areas of physics.

[1] Some of the major unsolved problems in physics are theoretical, meaning that existing theories seem incapable of explaining a certain observed phenomenon or experimental result.

The others are experimental, meaning that there is a difficulty in creating an experiment to test a proposed theory or investigate a phenomenon in greater detail.

One major problem lies in the mathematical framework of the Standard Model of physics, which is inconsistent with the theory of general relativity to the point that one or both theories break down under certain conditions (for example, within known spacetime singularities like the Big Bang and the centres of black holes beyond the event horizon).

[2] There are also questions beyond the Standard Model, such as the strong CP problem, neutrino mass, matter–antimatter asymmetry, and the nature of dark matter and dark energy.

Estimated distribution of dark matter and dark energy in the universe
Colour Confinement is the observed phenomenon that colored particles (quarks and gluons) cannot be isolated and are always bound to color neutral groups (at low energies). Such bound states are generally called hadrons.
Rotation curve of a typical spiral galaxy: predicted ( A ) and observed ( B ). Can the discrepancy between the curves be attributed to dark matter?
The " island of stability " in the proton vs. neutron number plot for heavy nuclei
A sample of a cuprate superconductor (specifically BSCCO ). The mechanism for superconductivity of these materials is unknown.
Magnetoresistance in a u = 8/5 fractional quantum Hall state