The https://www-thphys.physics.ox.ac.uk/people/AndreiStarinets/TUTORIALS_NOTES_GR/gr-cosmology-exam-paper-2011-solutions.pdf#page=24[official notes, PDF p. 24, handwritten p. 17] integrate the physical <particle horizon> and derive its early-time <redshift> dependence, explicitly stating the present matter-dominated approximation used in the printed expression.

Solution

Past exam of the general relativity and cosmology and condensed matter physics paper of Part B of the physics course of the University of Oxford / 2011 / Section V / 4 / Unlettered 2 / Solution

 Solution (source code)