Question

what is big bang theory

Answer 1

Solution :-

The big bang theory is a scientific theory about what happened at the very beginning of our universe and then how the stars and galaxies came into existence. According to the standard theory, our universe sprang into existence as "singularity" around 13.7 billion years ago. Singularities means a zone where some property is infinite. For example, at the center of a black hole.

Discoveries in Astronomy and Physics have shown beyond a reasonable doubt that our universe did in fact have a beginning. Prior to that moment there was nothing; during and after that moment there was something : our universe. The big bang theory is an effort to explain what happened during and after that moment. Our universe is thought to have begun as an infinitesimally small, infinitely hot, infinitely dense, something a singularity.

After its initial appearance, it apparently inflated (the big bang), expanded and cooled, going from very, very small and very, very hot, to the size and temperature of our current universe.

Answer 2

Answer:

The simplest way to explain the Big Bang Theory-- it says the universe as we know it started with a small singularity, then inflated over the next 13.8 billion years to the cosmos that we know today. The big bang is how astronomers explain the way the universe began. It is the idea that the universe began as just a single point, then expanded and stretched to grow as large as it is right now (and it could still be stretching). In 1927, an astronomer named Georges Lemaître propounded the theory of the Big Bang. He said that a very long time ago, the universe started as just a single point. He said the universe stretched and expanded to get as big as it is now, and that it could keep on stretching.

This theory explains how our universe began. About 14 billion years ago, all the matter that makes up the universe was squashed into an incredibly small space. Because the matter was so condensed, it wasn’t in any form we would recognize today. No atoms, or even particles. Suddenly, though, that matter went through a rapid inflation — an explosion, in a way. That’s the Big Bang. The result was a super-hot mass of matter, including light and charged particles such as protons and electrons. The matter cooled slowly over billions of years. As it cooled, it formed elements such as hydrogen. The matter also began to clump together into stars and planets. At the same time, the universe kept on cooling and expanding. In fact, the universe is still cooling and expanding today.