Big bang theory, Science

Assignment Help:

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.  


Related Discussions:- Big bang theory

How cells join together, In a unicellular organism, the interior  region of...

In a unicellular organism, the interior  region of  the organism  is no longer in contact with the external environment.  Thus simple processes  of  diffusion, phagocytosis, exocyt

Carbon dioxide, how to show air contains carbon dioxide

how to show air contains carbon dioxide

Explain the methods of food processing, The methods of food processing by c...

The methods of food processing by covering the two major methods- thermal processing dehydration.  Food processing methods which include  freezing, microwave proces

What is the important role of vitamin k, What is the important role of Vita...

What is the important role of Vitamin K Vitamin K , as you may already know, is a fat-soluble vitamin that plays an  important role  in  blood  clotting. It was  first observe

Materials and processes in design, a manufacturer of fasteners uses a four ...

a manufacturer of fasteners uses a four die nut former to produce blanks and the piercer punch began to break down using stainless steel bar stock. what change can be made so the m

Tuning in on the stars, Tuning in on the Stars: The fact that stars e...

Tuning in on the Stars: The fact that stars emit radiowaves was discovered accidentally in  1932  by  a young engineer Karl Jansky. He was trying to find the source of  noise

Assembling first aid box, Assembling First Aid Box : Your Counsellor will ...

Assembling First Aid Box : Your Counsellor will show you the contents of the first aid box available at the Study Centre. You observe the contents. As part of this activity, yo

1, what is a chemical

what is a chemical

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

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!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd