Let’s start with this article. The question is: What if time had no beginning? To get a little into the context, we have to go back in time and place to the era of the Big Bang, where we encountered the singularity. To date, general relativity has given us the best understanding of the universe, tracing its evolution up to the singularity. To go further, and find out what existed before the singularity, if there was a “before,” physicists resort to quantum gravity.
Did time start before? It’s hard to say which answer is more troubling. In the beginning, perhaps there was a beginning, or perhaps there was 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 decomposed into separate parts of space-time. At some level, there is a fundamental unity of space-time. Using this causal set approach to exploring the beginning of the universe, scientists have discovered that the universe may not have had a beginning, that it always existed in the infinite past and only recently evolved into what we call the Big Bang.
Both quantum physics and general relativity have turned out to be extraordinarily effective theories when it comes to deciphering the mysteries of the universe. However, quantum gravity remains elusive and is perhaps the most frustrating problem facing modern physics. On the other hand, general relativity is the most powerful and complete description of gravity ever devised. Unfortunately, it has its limits. In specific places, like black holes and the beginning of the universe, the mathematics of general relativity simply breaks down.
It was Stephen Hawking who was able to prove that general relativity (GR) collapses at the Big Bang singularity, but he left open the possibility that the Big Bang was not the beginning of time, but was preceded by the era of quantum gravity. . Which cannot be captured by RG. Therefore, the issue of the beginning of time must be addressed within the theory of quantum gravity. They explain Authors.
Causal set theory reinvents spacetime as a series of discrete pieces, or “atoms,” of spacetime. This theory would place strict limits on the proximity of events in space and time, as they cannot be closer than the size of an atom. For example, if you’re looking at your screen and reading this, everything looks smooth and continuous. But if you look at the same screen through a magnifying glass, you can see the pixels dividing up the space, and you’ll realize that it’s impossible to enlarge two images on your screen by more than one pixel, he explains. Live sciences.
The causal set approach clearly eliminates the problem of the Big Bang singularity, because, theoretically, singularities cannot exist. This means that it would be impossible to compress matter into infinitely small points; It cannot be smaller than the size of a space-time atom. This is where we return to the initial question, without the Big Bang singularity, what would our universe have begun?
There is still a lot of work here, but physicists say that what we consider the Big Bang was probably just a particular moment in the evolution of this ever-present causal set, rather than a true beginning.
The article is published in the database arXiv.
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