Varying fine-structure constant cosmography

Cosmography is a phenomenological and relatively model-independent approach to cosmology, where physical quantities are expanded as Taylor series in the cosmological redshift, or related variables. Here we apply this methodology constrain possible variations of fine-structure constant, α. Two peculiarities case existence high-redshift data, fact that one term directly tightly constraint by local laboratory tests with atomic clocks. We use clock together direct high-resolution astrophysical spectroscopy measurements α up redshift z∼7 additional model-dependent constraints on from cosmic microwave background big bang nucleosynthesis, place stringent (parts per million level) first two terms cosmographic series.