This is invented by G.GAMOV om 1956 based on Huble’s expansion theory that super-atoms including all the materials of the universe has been exploded and expanded to date.

1. Original atom : The initial small mass is called “original atom”. It is densely compacted with neutrons only and its temperature is regarded as 100 billion K.

1. Eruption : After the eruption of the original atom, some atoms are created in 30 minutes and they are flocked to become a star which is still expanding. The great explosion is called “Big Bang” and it is based on the theory of the great explosion.

2. The age of the universe : According to Huble’s Law V = H × r, if the galaxy far from r distance is moving with V velocity, r/V implies the time of running r distance with V velocity and then our galaxy and this galaxy are regarded as being together at the same amount of time in the past. In other words, according to the theory of great explosion, r/V = 1/H = t0 is numbered as the age of the universe. If H = 55km/s/Mpc, t0 = 1/H = 1 / 55km/s/Mpc ≒ 2x10; 10² year Thus, the age of the universe is estimated as about 20 billion year.