Phenomena or particles beyond the Standard Model of particle physics, potentially revealing extra dimensions or new fields.New physics refers to any phenomenon or particle that cannot be explained by the Standard Model of particle physics, the remarkably successful but incomplete theory describing known fundamental particles and forces. The Standard Model leaves several mysteries unresolved: the nature of dark matter, the tiny mass of neutrinos, the hierarchy problem (why gravity is so weak), and the matter-antimatter asymmetry of the universe. New physics would encompass the particles or forces that fill these gaps, such as supersymmetric partners, axions, sterile neutrinos, or extra spatial dimensions.
The term 'new physics' gained prominence in the 1980s as the Standard Model became established and its limitations became clear. The concept of physics beyond the Standard Model has been a major driver of theoretical and experimental work since then.
The search for new physics typically involves looking for deviations from Standard Model predictions. This can be done at high-energy colliders (like the LHC) by searching for new particles produced in collisions, or in precision experiments that measure known quantities with extreme accuracy, looking for tiny discrepancies. Cosmological observations, such as the expansion rate of the universe or the distribution of galaxies, also provide indirect probes of new physics that might have influenced the early universe.
While new physics has not yet been discovered, the search drives the development of advanced detector technologies, superconducting magnets, and data analysis techniques that find applications in medical imaging and computing.
The muon's anomalous magnetic moment shows a 4.2-sigma discrepancy between experiment and Standard Model prediction, one of the most significant hints of new physics that has not yet reached the gold-standard 5-sigma threshold for discovery.










