The Big Bang and the Formation of Light Elements

Formation of Light Elements in Big Bang Theory

• Key evidence for light element formation includes the observed abundance of light elements such as Hydrogen, Helium, and Lithium in the universe.
• The primary explanation for light element formation is primordial nucleosynthesis occurring within the first few minutes after the Big Bang.
• Notable light elements formed during the Big Bang include Hydrogen, Helium, and trace amounts of Lithium; however, Beryllium is not considered a product of Big Bang nucleosynthesis.

Conditions for Nucleosynthesis

• Estimated temperature of the universe during primordial nucleosynthesis is around 1 billion Kelvin (10^9 K).
• At these high temperatures, nuclear reactions could occur, allowing protons and neutrons to combine and form light nuclei.

Abundance of Light Elements

• Hydrogen is identified as the most abundant light element in the universe, making up about 75% of the total baryonic mass.
• Helium follows as the second most abundant light element, accounting for approximately 25% of the baryonic mass.