Is the Big Bang ‘just a theory’?

*This text was written by a TecMundo columnist; finally learn more.

In general, when talking about the Big Bang Theory, it is common to think that it explains how the universe formed. That’s not true, at least for now. The Big Bang Theory is simply about the so far successful attempt to understand the current state of the universe and why it is the way it is.

Before you understand what he is saying, it is important that there is no doubt in the meaning of the word “theory”. In our daily life, this word is used with a similar meaning to speculation or conjecture. For example, if someone tells you that they read a “theory” online that a movie villain is actually the main character, the meaning of the word is completely different from the one used in Science. To present a speculation, scientists use the word “hypothesis”.

In science, the word “theory” represents the best available explanation for some aspects of Nature. This explanation may include facts, laws, and hypotheses that have already been tested and proven. Contrary to what common sense might say, a scientific theory is something broader than a law. So, for example, The Theory of Relativity can explain all the situations that the Universal Law of Gravitation predicts and many situations where this law simply doesn’t work. Yes, there are cases where a scientific law may not fully describe nature.

Especially when we examine the Big Bang Theory, it tells us that our universe has gone through a rapid growth process and is still going through it. It is important to note that this expansion of the universe is not like an explosion, the literal translation of which is the English word “Bang”, a fact that does not help much in understanding the phenomenon.

The word explosion gives the idea that there is a central point that initiates this growth, but the growth of the universe is that infinite space grows on itself, and so it makes no sense to think of a central point. or we can understand that all points are equally central, as we have discussed in another text here.

because it’s a theory scientificThe Big Bang has plenty of evidence to prove it. To give an example, there is the removal of distant galaxies. In the 1920s, astronomer Edwin Hubble observed that our universe was expanding, using the brightness of some stars and galaxies to prove this. This observation suggests that since the universe is expanding, if it were possible to observe time flowing in the opposite direction, we would see a contraction of space causing all the matter in the universe to be gathered in a single point.

Based on this theory, it was possible to understand and explain with mathematical precision that this rapid expansion of the universe took place more than 14 billion years ago and how the universe formed as we know it from the very first moment, with planets, stars and planets. galaxies. All this represents the tremendous scientific success of this theory.

However, what caused all the matter in the universe to be initially concentrated in a single point? We do not know. How do the particles that make up matter and atoms behave in such an extreme situation? We do not know. What happened before the Big Bang? We do not know. Regarding these questions, Science’s lack of answers can be an initial discomfort, but it is precisely this inconvenience that keeps us searching for answers we don’t have. Still.

Rodolfo Lima Barros SouzaProfessor of Physics and columnist Technology World🇧🇷 He holds a master’s degree in Physics and Science and Mathematics Teaching in Public Perception of Science from Unicamp. Available on social networks as @rodolfo.sou.