HEP In the literature: open

Is the weak scale set by cosmological dynamics or selection?

In plain words

Instead of new particles at the TeV scale, the Higgs mass might have been adjusted during the early universe by a slowly evolving field, or selected among many possible universes. Such ideas predict light, weakly coupled particles instead of heavy ones.

Precise statement

Assess mechanisms in which v is fixed dynamically by cosmological evolution (relaxion scanning of $m_h^{2}$, NNaturalness, crunching of regions with large v) rather than by TeV-scale symmetry. An answer is a consistent model that reproduces $v = 246\,\mathrm{GeV}$ without large tuning and an experimental signature (for example relaxion-Higgs mixing or fifth forces) that can confirm or exclude it.

What would settle it

Detection or exclusion of the light scalar predicted by relaxation models through Higgs-mixing searches, fifth-force tests and rare-decay searches across its allowed mass range.

Status in the literature

Relaxion proposals date from 2015; consistent models exist but require long inflation or other non-minimal features, and none has a confirmed signature.