Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Big Bang theory:
The most important current theory for the origin of the universe is the Big Bang theory.According to this theory, the universe started with'a huge explosion. It was not an explosion like the ones with which we are familiar, which start from a definite centre and spread out. It was an explosion which occurred everywhere in space at the same time. It filled all space from the beginning, with every particle of matter rushing apart from every other particle. This was not a burst of matter into space but rather an explosion of space itself. Every particle of matter rushed away from every other particle. It is so far impossible to 'picture' the fi~st moment of 'creation' of the universe. One-hundredth of a second after the creation of the universe is the earliest time about which scientists can speak with any confidence. At this instant, the temperature of the universe was about a hundred billion degrees centigrade. This-is much hotter than in the centre of even the hottest star. At such temperatures none of the components of ordinary matter, atoms, molecules, or even nuclei of atoms, could have held together. Instead, the matter rushing apart in the explosion consisted of various types of elementary particles. The particles most abundant in the early universe were the electrons, positrons and neutrinos. There were also some protons and neutrons. The rest of the universe was filled with energy. It was a kind of a cosmic soup. As the explosion continued, matter and energy rushed apart, the universe expanded and the temperatures dropped, reaching 30 billion (3x1010) degrees centigrade after about one-tenth of a second; 10 billion degrees after about one second; and 3 billion degrees after about fourteen seconds. At the end of the first three minutes, the universe became cool enough (about 1 billion 0C) for the protons and neutrons to begin to form into simple nuclei. The first to be formed was the nucleus of heavy hydrogen which was made up of one proton and one neutron. There were also helium nuclei made of two protons and two neutrons. It was still too hot for atoms to hold together, they were ripped apart as soon as they were created. This matter continued to rush apart, becoming steadily cooler and less dense.
Many thousands of years later, it became cool enough for electrons to join with nuclei to form atoms of hydrogen and helium. Soon, the resulting gas began to form clumps under the influence of gravitation. These clumps ultimately condensed to form the galaxies and stars of the present-day universe, almost 5 billion years after the Big Bang. There is another theory about the origin of the universe known as the steady state theory. This theory holds that the universe has always been just about the same as it is now. As it expands, new matter is created continuously to fill up the gaps between the galaxies. Thus, the problem of the origin and early moments of the universe is banished: there was no early universe. However, the Big Bang theory is the most favoured by the astronomers and astrophysicists. Why is it so? This is due to the evidence based on observations which lend support to the 'Big Bang' universe.
types, principle and working
Explain Betice Jones Protein - abnormal constituent of urine Betice-Jones Protein: Bence-Jones proteins are the small proteins (dimers of iminunoglobuljn light chains) normally
What protist changes shape constantly and flows around it''s food to engulf it
make a list of food item used at home .categorize them as healthy food [energy giving, body building and protective food] and unhealthy food [fried and greasy]
Another way to show that air expands when heated Snap a toy balloon over the neck of a small bottle and place the bottle in a pan of warm water.
Granulocyte macrophage colony stimulating factor (GM-CSF): Stem cells obtained from the bone marrow are capable of giving rise to countable colonies of daughter cells in splee
What are the ratios allowed for three year olds and Child Care Centers in Colorado and what is the citation of the rules that addresses ratios?
what is subphylum chordata?
Why are clouds White? Why does a day have 24 hours? Answer: A cloud is a visible accumulation of very tiny water droplets or solid ice that float in the air. Clouds are usuall
why cant the eye see behind you
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd