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Einstein
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Hydrogen and Helium were the main constituents formed soon (thousands of years?) after the big bang. Why did they not burn (as they are flammable), I am sure the universe was hot enough then to ignite it?
Originally posted by Einstein
Hydrogen and Helium were the main constituents formed soon (thousands of years?) after the big bang. Why did they not burn (as they are flammable), I am sure the universe was hot enough then to ignite it?
Hydrogen burns if you combine it with oxygen. There was not then nor is there now a large amount of oxygen (percentagewise) in the universe.Originally posted by Einstein
Hydrogen and Helium were the main constituents formed soon (thousands of years?) after the big bang. Why did they not burn (as they are flammable), I am sure the universe was hot enough then to ignite it?
Originally posted by Einstein
Hydrogen and Helium were the main constituents formed soon (thousands of years?) after the big bang. Why did they not burn (as they are flammable), I am sure the universe was hot enough then to ignite it?
After the Big Bang, the universe was extremely hot and dense. As it expanded and cooled, protons and neutrons combined to form the nuclei of hydrogen and helium atoms. These atoms then combined to form the first stars and galaxies.
At the time of their formation, the universe was still expanding and cooling. The temperature and pressure were not high enough for nuclear fusion to occur, which is necessary for the burning of hydrogen and helium atoms.
As the universe continued to expand and cool, gravity caused the gas and dust to clump together, forming dense clouds. These clouds exerted enough pressure and temperature to trigger nuclear fusion, leading to the formation of stars.
The ratio of hydrogen to helium is crucial in the formation of the universe. If the ratio had been slightly different, the universe would have either expanded too quickly, preventing the formation of stars, or collapsed too quickly, preventing the formation of galaxies. The precise ratio of 75% hydrogen and 25% helium was necessary for the universe to evolve as it has.
Scientists have observed the chemical composition of stars and interstellar gas, which shows a high percentage of hydrogen and helium. This confirms that these elements were the first to form after the Big Bang, and their abundance has remained relatively unchanged over time.