Question

10 −5 seconds after the big bang

a. Nucleosynthesis.
b. Quark epoch.
c. Photon epoch.
d. Proton formation.

Answer 1

At 10−5 seconds after the Big Bang, the universe transitioned from the Quark Epoch to the Hadron Epoch, eventually leading to nucleosynthesis.

Step-by-step explanation:

The age 10−5 seconds after the Big Bang marks the end of the Quark Epoch and the beginning of the Hadron Epoch. During the Quark Epoch (10−11 → 10−6 s), the universe cooled sufficiently to allow quarks to combine into hadrons, including protons and neutrons. Following this epoch, as the universe continued to expand and cool, protons and neutrons were able to combine to form the first nuclei in a process known as nucleosynthesis. This period of nucleosynthesis extended from roughly 225 seconds to 1000 years after the Big Bang.