Gravitational lens time-delay as a probe of a possible time variation of the fine-structure constant

A new method based on large scale structure observations is proposed to probe a possible temporal variation of the fine-structure constant (alpha). Our analyses are based on time-delay of Strong Gravitational Lensing and Type Ia Supernovae observations. By considering the runaway dilaton scenario, where the cosmological temporal evolution of the fine-structure constant is given by Delta alpha alphaapproximate to-gamma ln(1+z), we obtain limits on the physical properties parameter of the model (gamma) at the level 10-2 (1 sigma). Although our limits are less restrictive than those obtained by quasar spectroscopy, the approach presented here provides new bounds on the possibility of Delta alpha alphanot equal 0 at a different range of redshifts.

Automated summary

A new method based on large scale structure observations is proposed to probe the temporal variation of the fine-structure constant, obtaining limits on the physical properties parameter of the model at the level of 10^-2. The approach provides new bounds on the possibility of the fine-structure constant not being equal to 0 at different redshifts.