interagon
Interagon is a hypothetical particle or field proposed within certain speculative theories of fundamental physics as a mediator of interactions between otherwise decoupled sectors. In these frameworks, an interagon couples feebly to standard-model fields and to new hidden-sector fields, enabling indirect communication between sectors without direct renormalizable couplings. The exact properties of an interagon vary across models; typical versions consider either a neutral scalar or a vector boson with a mass scale ranging from sub-eV to multi-TeV and with very small coupling constants. Some proposals regard the interagon as a short-range mediator, others as a light or even long-range field depending on cosmological constraints.
Role and implications: Interagons are invoked to generate effective interactions between dark matter and ordinary matter,
Experimental status: There is no empirical evidence for an interagon. It remains a speculative construct discussed
See also: hidden sector, dark photon, axion-like particle, portal theory, beyond the Standard Model.