42. By the reckoning of almost any cosmologist, the main physics theory ingredient to cosmology is: a) planetary systems. b) stellar physics. c) general relativity. d) the quantum theory of solids. e) helioseismology. 43. Using philosophical ideas as a source of interesting cosmological hypotheses in research using the scientific method is valid as long as the hypotheses are taken as: a) dogma. b) things to be tested empirically. c) truth. d) mythology. e) false