Photon density can be found in the denominator of a parameter characterizing the extent of this property. For 10 points each:
[10m] Give the name for the excess of normal matter over antimatter in the universe, which can't be explained by the Standard Model.
ANSWER: baryon asymmetry [prompt on matter asymmetry or matter-antimatter asymmetry]
[10h] Sakharov's three conditions for the generation of excess matter are the absence of this condition, along with baryon number violation and CP violation. When this condition holds, the CPT theorem requires that matter and antimatter be created in equal amounts.
ANSWER: equilibrium [or any answer indicating being in thermal equilibrium]
[10e] We know that there's more matter than antimatter throughout the observable universe, rather than "bubbles" of matter and antimatter, since their boundaries would make gamma rays through this phenomenon that occurs when a particle and its antiparticle collide, destroying both of them.
ANSWER: annihilation [or word forms such as annihilate]
<Kevin Ye , Science - Physics - Particles/HEP>