 Inflationary cosmology originally promised a powerful unification of particle physics and cosmology. The earliest inflationary models explored the consequences of specific scalar fields introduced in particle physics (the then supposed Higgs field for the strong interactions). Yet theory soon shifted to treating the scalar field responsible for inflation as the “inflaton” field, leaving its relationship to particle physics unresolved, and the promise of unification unfulfilled. If the properties of the inflaton field are unconstrained, inflationary cosmology is extremely flexible; it is possible to construct an inflationary model that matches any chosen evolutionary history of the early  universe.[28]  Specific models of inflation, insofar as they specify the features of the field or fields driving inflation and its initial state, do have predictive content. In principle, cosmological observations could determine some of the properties of the inflaton field and so select among them (Martin et al. 2014). This could in principle then have implications for a variety of other experiments or observations; yet in practice the features of the inflaton field in most viable models of inflation guarantee that it cannot be detected in other regimes. The one exception to this is if the inflaton were the electroweak Higgs particle detected at the LHC (Ellis &amp; Uzan 2014). This remains a viable inflaton candidate, so testing if it is indeed the inflaton is an important task (Bezrukov &amp; Gorbunov 2012).