Summary
Highlights
The formation of light elements is explained through the Big Bang theory, defined as a scientific principle explaining phenomena. The Big Bang proposes the universe originated from an extremely compact, dense, and hot state, undergoing a sudden expansion billions of years ago, and has been expanding and cooling ever since.
The light elements found in the universe include hydrogen (found in the sun and stars), helium (used in balloons), lithium (found in batteries), and beryllium (used in aircraft components, missiles, and satellites).
The Big Bang theory suggests the universe began from a tiny, dense, hot energy that expanded explosively. This energy condensed into quarks, which then formed protons and neutrons. As the universe cooled, these particles combined to form nuclei, a process called nucleosynthesis. Nucleosynthesis is the creation of new atomic nuclei from pre-existing nucleons (protons and neutrons) through nuclear fusion. It occurs in two phases: Big Bang/primordial nucleosynthesis and stellar nucleosynthesis. The high energy and temperature of the early universe caused protons and neutrons to combine.
Hydrogen, a one-proton element, makes up about 75% of the ordinary matter in the universe by mass. Deuterium, a hydrogen isotope, makes up about 0.001%. Isotopes of helium, with two protons, constitute close to 25%. Lithium isotopes, with three protons, were only a tiny trace, and a small amount of beryllium isotopes, with four protons, may have formed and later decayed into lithium.
Each of these nuclei initially had a positive charge. As the universe cooled further, negatively charged electrons combined with these positive nuclei to form stable, neutral atoms. The light elements formed through nucleosynthesis include hydrogen, deuterium, helium, lithium, and beryllium.