The Big Bang Theory is a series of criteria that affirm that the universe was created after a great explosion called the “Big Bang”. Physicist George Gamow was the scientist who came up with such a theory.
What does it consist of?
This hypothesis establishes that everything that exists now in the universe started from nothing. Before the aforementioned explosion, matter was only a point of infinite density that eventually exploded and generated everything that today we can call “universe”.
The big explosion caused matter to expand a great distance and, after other processes, planets and other bodies were formed . Each particle spread rapidly, separating one from the other.
This theory also defines the composition of the matter that was released throughout the universe, which has more than 89 particles.
The hydrogen and helium would be the major players of the Big Bang, elements that are highly volatile. The galaxies and stars would form after the cooling and condensation of these elements.
As the universe expanded, the residual radiation from the explosion continued to cool, reaching a temperature of about 3 K (-270 ° C). In 1965, the Big Bang theory was confirmed by verifying that these temperatures are true, thanks to the efforts of radio astronomers.
Doubts about the theory
Although many of the ideas raised by Gamow have been confirmed in practice, this theory does not explain, logically, many of the doubts that arise from his explanation.
One of those doubts is whether the universe is closed or open, more specifically, you want to solve the question of whether matter continues to expand or will contract again . The resolution of this doubt lies in the understanding of dark matter, but to date it is a mystery.
There is a group of cosmologists investigating gravity and plasma phenomena to try to understand the structure, evolution and destiny of the Universe.
Examples of Big Bang Theory
Examples of important facts about the Big Bang:
- The Big Bang is said to have occurred about 13.7 billion years ago.
- According to scientists, the universe expanded faster than the speed of light in the first second after the explosion.
- Some scientists believe that the universe, before the Big Bang, was a compressed mass, very small (just a few millimeters) and hot.
- Proponents of this theory claim that the laws of physics and chemistry were formed during the first second of the Big Bang.
- Scientists Penzias and Wilson were the ones who discovered the cosmic microwave background in 1964, one of the tests that validates the Big Bang theory. It is a cosmic fog that is spread throughout the universe.
- Stars and galaxies were formed thanks to the difference in temperatures in the cosmic microwave background, which was 100 microkelvin with almost no change.
- The scientists explain that, while the light elements were created in the first instant after the Big Bang, the heavy elements condensed inside the stars and expanded widely in supernova explosions.
- It is estimated that the first 380,000 years of the Big Bang, the universe was too hot due to the main consequence of the explosion: the formation of a dense plasma, so that not even the light shone.
- There are four tests of the validity of the theory: the first is the cosmic microwave background, something already known, the other three relatively new are: the expansion of the universe according to Hubble’s law, relative abundance of light elements and distribution of structures.
- According to, dark matter, which makes up 72% of the universe, still makes the universe expand.
- The theory proposes an end hypothesis called “Big Crunch” (The Great Implosion), where the universe will stop expanding collapsing in its entirety.
These are some examples of alternative theories to the Big Bang:
- Cyclic Universe: the universe went through cycles of expansion (Big Bang) and then high compression (Big Crunch).
- Holographic Universe : the universe could be the same as a 3D hologram projected onto a sphere.
- Torsion of space-time : the universe would behave like an object on the edge of a black hole. Are there infinite universes?
- Universe without beginning or end: proposes the existence of a universe prior to ours.
- Eternal Inflation: there are several universes where each one repeats itself eternally and has its own physical laws, different from each other.