Physicists add validity to string theory

Dec. 18 () –

A team of physicists has taken an important step forward in validating string theory by using a innovative mathematical method that points to its “inevitability”.

string theory, conceptualized more than 50 years ago as a framework to explain the formation of matterremains elusive as a “demonstrable” phenomenon.

This theory postulates that the most basic components of nature are not particles, but rather one-dimensional vibrating strings that move at different frequencies to determine the type of particle that emergessimilar to how the vibrations of stringed instruments produce a variety of musical notes.

In his work, published in the magazine Physical Review Lettersresearchers from New York University and Caltech asked the following question: “What is the mathematical question for which string theory is the only answer?” This approach to understanding physics is known as “bootstrap,” reminiscent of the saying “pulling yourself up by your bootstraps”: produce results without additional assistance or, in this case, input.

The bootstrap has previously allowed physicists to understand why general relativity and various particle theories (such as gluon interactions within protons) are mathematically inevitable: they are the only consistent mathematical structures, under certain criteria.

However, the same question had not previously been answered for string theory: What criteria uniquely determine it by mathematically selecting it from the set of all possible theories?

In the paper, the scientists discovered a way to start these string amplitudes, specifically, building them by creating mathematical formulas. By implementing special mathematical conditions into their formulas for scattering amplitudes (which describe how particles interact and eventually form), the group found that string theory amplitudes emerged as the only consistent answer.

“This paper provides an answer to this string theory question for the first time,” says in a statement Grant Remmen, a James Arthur Postdoctoral Fellow at New York University’s Center for Cosmology and Particle Physics and one of the paper’s authors.

“Now that these mathematical conditions are known, we are one step closer to understanding whether and why string theory should describe our universe.”

The authors of the article, who also include Clifford Cheung, professor of theoretical physics at Caltech, and Aaron Hillman, postdoctoral researcher at Caltech, add that this advance may be useful to better understand quantum gravity: it seeks to reconcile the theory of Einstein’s relativity, which explains gravity on a large scale, with quantum mechanics, which describes the activity of particles on the smallest scales.

“This approach opens a new area of ​​study in the analysis of the singularity of string amplitudes,” explains Remmen. “The development of tools described in our research can be used to investigate deformations of string theory, which will allow us to map a space of possibilities for quantum gravity.”