Light Elements
The Production of the Light Elements
This is the periodic table of the elements. The photo is in the public domain.
Where do the elements in our universe come from? The SBBM predicts that nuclei were produced in the early universe, and it predicts how many of each type were produced. Since light elements are easier to produce than heavy elements, the SBBM predicts that there should be more hydrogen than helium, more helium than lithium, etc. Since the universe cooled as it expanded, however, virtually no elements heavier than lithium--and only a tiny amount of lithium was produced--were produced in the early universe.
Above, we show the periodic table of the elements. Hydrogen and helium are listed at the very top. Where did the elements heavier than hydrogen and helium come from? The only known processes that could have produced heavier elements occur in the cores of stars—either during normal fusion, or during massive stellar explosions called supernovae.
Since the universe is expanding and has been from its inception, the universe has been cooling and therefore the production of nuclei took place within about the first 20 minutes. The SBBM predicts [3] that
2H/ 1H = 2.60 x 10-5 (+0.19, -0.17)
3He/ 1H = 1.04 x 10-5 (+0.04, -0.04)
4He/ 1H = 0.2479 (+0.0004, -0.0004)
7Li/ 1H = 4.15 x 10-10 (+0.49, -0.45)
This can be compared to experiment by using spectroscopy to determine the elemental composition of stars and nebulae, for instance. Next, we discuss the expansion of the universe.