the universe began with a Big Bang哪位大哥大姐帮忙用英文写一段关于宇宙大爆炸的作文

the universe began with a Big Bang哪位大哥大姐帮忙用英文写一段关于宇宙大爆炸的作文
the universe began with a Big Bang哪位大哥大姐帮忙用英文写一段关于宇宙大爆炸的作文

the universe began with a Big Bang哪位大哥大姐帮忙用英文写一段关于宇宙大爆炸的作文
Big Bang theory of the main opinion is that our universe had a period from hot to cold evolutionary history. During this period, the universe is not a static system, but are constantly expanding, so that the density of matter from the dense to dilute to evolve. This from hot to cold, from dense to dilute the process as the outbreak of an enormous scale. According to Big Bang cosmology opinion, the big bang the whole process are: early in the universe, the temperature is extremely high at 10 billion degrees. Material density is likely to be considerable, the whole system of the universe balanced. The universe only neutrons, protons and electrons, photons and neutrinos and other elementary particles form the material. However, because the whole system continues to expand, the results of the temperature dropped quickly. When the temperature dropped to around one billion degrees, neutrons begin to lose the freedom of the conditions exist, it either happened decay, or with protons into deuterium, helium and other elements; chemical element is formed from the beginning of this period. Temperature further dropped to one million degrees, the early formation of chemical elements in the process of The End (see element synthesis theory). The universe's material is mainly of protons and electrons, photons, and some of the more lighter nuclei. When the temperature is reduced to several thousand degrees, the radiation diminishes, the universe is mainly gaseous material, the gas gradually unite into a gas cloud further the formation of various star systems, to become the universe we see today.
Gamow in 1948 from the hot set up since the concept of the Big Bang, through decades of efforts, the universe, scientists outline for us the history of such a universe:
Big Bang beginning about 137 million years ago, a very small volume, high density, high temperature.
Big Bang 10 ~ 43 seconds ago the universe emerged from the quantum background.
Big Bang the first 10 ~ 35 seconds with a broken down into strong, weak electric and gravitational force.
Big Bang 10 ~ 5 second 10 trillion degrees, the formation of protons and neutrons.
0.01 seconds after the Big Bang one hundred billion degrees, photon, electron, neutrino mainly accounted for only 10 billionths of a proton neutron, thermal equilibrium state, the rapid expansion of the system, temperature and density continues to drop.
0.1 seconds after the Big Bang 30 billion later, the neutron proton ratio dropped to 0.61 from 1.0.
One second after the Big Bang 10 billion later, the neutrinos escape outward, electron-positron annihilation reaction, nuclear power is still less than the neutron and proton bound.
13.8 seconds after the Big Bang 30 billion kwh, deuterium, helium nuclei stability category (chemical element) form.
35 minutes after the Big Bang, after three hundred million degrees, nuclear process to stop, can not form a neutral atom.
Big Bang 30 years after 3000, the chemical combination of the role of neutral atoms so that the formation of the universe, the main components of gaseous substances, and gradually the gravitational effect of self-cohesion, high-density gas into the clouds, until the stars and stellar systems.
According to the Hubble constant can be estimated around 150 million years ago, the universe began in a singular point.
Wenger. Wave Miao said: "The explosion 1 / 100 second when the temperature was 100 billion degrees Celsius, the universe at its most simple state of thermal equilibrium. From a purely energy generated by the photon and electron-positron blend together, even the mirage-like micro - This son also soak in hot soup pots (what we call soup of elementary particles) Lane. photon and proton ratio of 10 to 1. exploded one second after the temperature has dropped to 10 billion degrees Celsius, neutrinos begin to escape from the heat balance extricate . 3 minutes is a epoch-making time, the temperature has dropped to one billion degrees Celsius, electron-positron annihilation finish. the universe, mainly by light, positive and negative component neutrino, nuclear particles represents a very small share of one of the ratio of hydrogen and helium for 73 : 27. The other is by the annihilation of many particles with the same nuclear electron scarce. since there is no major event happened 70 million years, until the temperature has dropped to 3000 degrees Celsius, the free electron gradually have their own owners, and nuclear form of hydrogen and helium, material was hot out of radiation balance, beginning the universe transparent.