What is the minimum number of dimensionless physical constants from which all other dimensionless physical constants can be derived? Are dimensional physical constants necessary at all? Dimensionless physical constants: At the present time, the values of various dimensionless physical constants cannot be calculated they can be determined only by physical measurement.Theory of everything: Is there a singular, all-encompassing, coherent theoretical framework of physics that fully explains and links together all physical aspects of the universe?.Another problem lies within the mathematical framework of the Standard Model itself-the Standard Model is inconsistent with that 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). There are still some questions beyond the Standard Model of physics, such as the strong CP problem, neutrino mass, matter–antimatter asymmetry, and the nature of dark matter and dark energy. 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.

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 following is a list of notable unsolved problems grouped into broad areas of physics. You can help by adding missing items with reliable sources. This is a dynamic list and may never be able to satisfy particular standards for completeness.

List of physics phenomena