Comparing cooling temperature changes at different stages of the universe's life provides evidence of

Question

the rate of the universe's initial expansion, or the forces that produced the original singularity, or the radiation generated by the Big Bang expansion
Measuring the universe's ratio of hydrogen and helium provides evidence that these elements were
generated by the universe's ongoing expansion, or formed from the universe's original particles or formed long after the universe had cooled

Answer 1

The statements you provided can be analyzed in terms of their scientific context regarding cosmology and the Big Bang theory.

1. Cooling Temperature Changes in the Universe:

   • Evidence of the rate of the universe's initial expansion: This is indeed supported by the observations of the cosmic microwave background (CMB) radiation and the cooling of the universe over time. The temperature changes help us understand how rapidly the universe expanded shortly after the Big Bang.
   • Forces that produced the original singularity: While cooling temperature changes provide information about the expansion history of the universe, they do not directly evidence the forces extrapolated from the singularity itself. The exact nature of the singularity and the forces involved remain speculative and are an area of ongoing research.
   • Radiation generated by the Big Bang expansion: This is accurately described. As the universe expanded, it cooled, leading to the release of radiation that is observed today as the CMB.

2. Measuring the Universe's Ratio of Hydrogen and Helium:

   • Generated by the universe's ongoing expansion: This is somewhat misleading. The ratios of hydrogen and helium observed today do not arise primarily from ongoing expansion but rather from processes that occurred during the early universe.
   • Formed from the universe's original particles: This is accurate. The primordial nucleosynthesis that occurred in the first few minutes after the Big Bang produced the observed ratios of hydrogen, helium, and trace amounts of other light elements.
   • Formed long after the universe had cooled: This is not accurate in the context of the formation of hydrogen and helium. Most of the hydrogen and helium we observe today were formed during the early moments of the universe, well before it had cooled significantly and formed structures like stars and galaxies.

In summary, the rates of cooling and elemental ratios provide critical evidence about the history and evolution of the universe, particularly related to the events of the Big Bang and the processes that followed.