Hi world! A new approach to physics in the space of Sitter

Physicists have been trying for decades to reconcile quantum mechanics, the physics of the very small, with gravity, and the physics of the very large. While many academics work on quantum gravity, they often use models that do not take into account certain aspects of our own universe, such as its accelerated expansion. A team from the Graduate University (OIST) of the Institute of Science and Technology of Okinawa has announced a new approach to quantum gravity using a model closer to our reality.

Write in Physical examination D, the team reports their progress on the scattering matrix for massless fields, or S-matrix, an expression that predicts what will happen when particles at an infinitely long distance come together, interact and grow. In other words, the matrix S uses starting points to predict the results. It is important to note that this concept can be applied to a space of Sitter, a universe which is growing at an accelerated pace, just like ours.

In this article, the team calculates the S matrix in Sitter's space for the simplest scenario, which involves free and non-interacting particles. This expression is known as the free S matrix.

"The free S matrix is ​​more than elegant mathematics – it has the potential to explain more realistic scenarios," said Adrian David, one of the authors of the study. "We will now start thinking about such scenarios, going beyond individual fields to explore what happens when these fields interact."

Hi world!

A "Hello world!" is a computer program that displays this simple message out. This is a test used by software developers to confirm that the underlying programming language is working properly. Developers typically perform this consistency check before using the language in more complex environments with useful outputs. The free S matrix is ​​like a "Hello, World!" program used for mathematics in a simple context.

"As a consistency test in computer programming, the output" Hello, World! "The message is less interesting than the underlying language used to create it," says David. "Similarly, the free S matrix is ​​less interesting in itself, but more in the questions that it could allow us to answer."

"We live in an expanding universe, a Sitter space, and it seems that these conditions are now permanent," says Professor Yasha Neiman, Quantum Gravity Group Leader. "This information needs to be incorporated as a cornerstone in our description of reality."

For the moment, the team will work on the next stage of the problem: applying the free S matrix to more complex scenarios echoing reality. Then, they could better understand: is it just a beautiful math or more than a beautiful face?