Experimentally distinguishing different primordial paradigms that could lead to the Big Bang model is an outstanding challenge in modern astrophysics and cosmology. In this talk we introduce a novel type of observables that can be used as an independent and direct evidence for the inflation paradigm or other possible alternatives. These signals are induced by Standard Clocks in the primordial epoch, and are capable of directly recording the scale factor of the primordial universe as a function of time a(t), which is the defining property of different paradigms. We present an interesting candidate in the Planck data, which has all the characteristics of inflation.