The universe could not have a beginning – teach me about science

The universe could not have a beginning – teach me about science
Artist’s impression of the Big Bang (Credit: Shutterstock).

Let’s start with this article, the question is, what if time had no beginning? To get into context a bit, we have to go back in time and space to the Big Bang era, where we came across the singularity. So far, general relativity has provided us with the best understanding of the universe, tracing its evolution back to the singularity. Moving forward, and finding out what was before the singularity, if there was “before,” physicists turn to quantum gravity.

Has time started before? It is difficult to say the most annoying answer, there may have been a beginning in the beginning, or there may have been no beginning. Our universe may have always existed, and a new theory of quantum gravity reveals how it might work.

The team used a new theory of quantum gravity called causal group theory. According to this theory, space and time are divided into separate parts of spacetime. At a certain level, there is a basic unit of space-time. Using this causal ensemble approach to exploring the beginning of the universe, scientists have discovered that the universe may have had no beginning, that it had always existed in the infinite past and only recently evolved into what we call the Big Bang.

Both quantum physics and general relativity have proven to be extraordinarily effective theories in unraveling the mysteries of the universe. However, quantum gravity remains elusive and is perhaps the most frustrating problem facing modern physics. General relativity, on the other hand, is the most powerful and comprehensive description of gravity ever devised. But unfortunately, it has its limitations, in certain places like black holes and the beginning of the universe, the mathematics of general relativity breaks down.

Stephen Hawking was the one who was able to show that general relativity (GR) breaks down at the Big Bang singularity, but left out the possibility that the Big Bang was not the beginning of time, but was preceded by an era of quantum gravity. which cannot be captured by RG. Therefore, the question of the beginning of time must be addressed within the theory of quantum gravity, explain authors.

Causal group theory reinvents spacetime as a series of discrete pieces, or “atoms,” of spacetime. This theory would place strict constraints on the proximity of events in space and time, as it could not be closer than the size of an “atom”. For example, if you are looking at your screen reading this, everything will look smooth and continuous. But if you look at the same screen through a magnifying glass, you’ll be able to see the pixels that divide the space, and you’ll realize that it’s impossible to get two images on your screen closer than one pixel, he explains. life.

The causal ensemble approach obviously eliminates the Big Bang singularity problem because, in theory, singularities cannot exist. That is, it will be impossible to compress the material into very small points; It cannot be smaller than the size of an atom of spacetime. This is where we return to the initial question, without the singularity of Big Bang, what would the beginning of our universe look like?

There is still a lot of work to do here, but physicists say that what we perceive as the Big Bang may have been just a certain moment in the evolution of this ever-present causal group, rather than a real beginning.

The article is published in a database arXiv.

Share knowledge, share knowledge.

Leave a Reply

Your email address will not be published. Required fields are marked *