What is the universe?

The universe is everything, without exception. Matter, energy, space and time, everything that exists is part of the Universe. 

The Big Bang theory explains how formed said that some 13,700 million years ago the area had a density and an infinite temperature.

There was a violent explosion and, since then, the universe goes losing density and temperature.

What is the big bang?

The Big Bang is a singularity, an exception that cannot explain the laws of physics. We can know that step from the first moment, but the time and size zero still do not have scientific explanation. 

How did it originate this singularity of the big bang?

The singularity of the Big Bang theory, comes out of the math of Einstein's theory of general relativity, which describes how mass warps space-time, and another equation (called Raychaudhuri's equation) that predicts whether the trajectory of something will converge or diverge over time.

What is the Raychaudhuri's equation?

The equation Raychaudhuri, or Landau-Raychaudhuri equation, is a fundamental result describing the movement of bits of matter.

The equation is important as an overriding theme of the Penrose-Hawking singularity theorems and to the study of the exact solutions of general relativity , but has independent interest, since it offers a simple and general validation of our expectation that the intuitive gravitation must be a universal appeal, the force between two pieces of mass-energy in general relativity, as it is in the theory of gravitation of Newton .

What is the theory of relativity?

The theory of relativity includes both the theory of special relativity as to general relativity, made by Albert Einstein at the beginning of the twentieth century; they were intended to solve the incompatibility between existing Newtonian mechanics and electromagnetism. The theory of special relativity, published in 1905, deals with the physics of the motion of bodies in the absence of gravitational forces, which made compatible Maxwell's equations of electromagnetism with a reformulation of the laws of motion. The theory of general relativity, published in 1915, is a theory of gravity that replaces newtonian gravity, although coincides numerically with her for weak gravitational fields and "small" speeds. The general theory is reduced to the special theory in the absence of gravitational fields.

When is scientifically accepted the theory of relativity as a fact true?

In 1919, Newton’s law of universal gravity still dominated scientific discourse, as it provided extremely accurate explanations of physical observations. But Einstein had a major issue with Newton’s theory: It wasn’t consistent with his own special theory of relativity, which predicted that space and time were relative, forming a four-dimensional continuum called spacetime. He conceived a general theory of relativity, in which gravitational fields would cause warps in spacetime, thus weaving gravity into the continuum.

Such a tiny difference seemed impossible to measure by earthly experiments. In fact, the two theories, though fundamentally opposed, made highly similar predictions for almost all tests of gravity and light. As a result, it was futile to try to understand which one provided a more accurate description of the fundamental laws of the universe.

Sir Frank Watson Dyson, Astronomer Royal of Britain, conceived in 1917 the perfect experiment to resolve the issue. A total solar eclipse on May 29, 1919, would occur just as the sun was crossing the bright Hyades star cluster. Dyson realized that the light from the stars would have to pass through the sun’s gravitational field on its way to Earth, yet would be visible due to the darkness of the eclipse. This would allow accurate measurements of the stars’ gravity-shifted positions in the sky.

Eddington, who led the experiment, first measured the “true” positions of the stars during January and February 1919. Then in May he went to the remote island of Príncipe (in the Gulf of Guinea off the west coast of Africa) to measure the stars’ positions during the eclipse, as viewed through the sun’s gravitational lens.

Conclusion

this experiment of the solar eclipse in 1919, was to scientifically confirm the theory of relativity by Albert Einstein, and I think that plates in black and white, showing the displacement of the light of the stars just grazed the edge of the Sun, hardly will show the effect of the atmosphere in the photo, that is why the experiment confirmed the theory of relativity is flawed by the atmosphere, which generates a new shadow of a doubt, not only on the theory of general relativity, but also of all the mathematical formulas that originate from this theory, because it would be a serious mistake recognize problems in the theory and not to accept them in their explanations, as in this case the theory of the big bang, which is product of the mathematics of this theory

Reference

https://es.wikipedia.org/wiki/Teor%C3%ADa_de_la_relatividad

http://www.wired.com/2009/05/dayintech_0529/

http://www.livescience.com/49958-theory-no-big-bang.html

https://en.wikipedia.org/wiki/Raychaudhuri_equation

http://www.astromia.com/universo/eluniverso.htm