Thermality in de Sitter spacetime and holography

Assuming the existence of a dS/conformal field theory correspondence we study the holograms of sources moving along geodesics in the bulk by calculating the one point functions they induce in the boundary theory. In analogy with a similar study of uniformly accelerated sources in AdS spacetime, we argue that comoving geodesic observers correspond to a coordinate system on the boundary in which the one point function is constant. For ${\mathrm{dS}}_3$ we show that the conformal transformations on the boundary that achieve this, when continued suitably to Lorentzian signature, induce nontrivial Bogoliubov transformations between modes, leading to a thermal spectrum. This may be regarded as a holographic signature of thermality detected by bulk geodesic observers.