A scientific theory is an explanation of the aspects of the natural world and which can be tested and verified. By the use of methods like observations, While the scientific laws are also based on repeated experiments or observations. Scientific theories are evaluated through the use of reasoning.
Measuring the amount of deu terium in the universe allows us to set a limit on the density of ordinary matter of universe. Density of the universe is about 9×10-27 kg m-3, because of the way in which deu terium was created in the Big B ang, an exact measurement of the amount of deuterium would allow scientists to set limits on the models of the great explosion.
