Recent decades have witnessed remarkable progress in establishing rigorous mathematical frameworks for quantum field theory (QFT), conformal field theory (CFT), quantum gravity and string theory.

Quantum field theory (QFT) remains the cornerstone of our understanding of particle interactions, unifying the principles of quantum mechanics with special relativity by describing particles as ...

String theory—the idea that particles are not point-like, but instead one-dimensional strings—is a popular theoretical framework that attempts to combine general relativity and quantum field theory ...

In 1980, Stephen Hawking gave his first lecture as Lucasian Professor at the University of Cambridge. The lecture was called "Is the end in sight for theoretical physics?" Forty-five years later, ...

The prevailing assumption has been that Einstein's theory of gravity must be modified, or 'quantized', in order to fit within quantum theory. This is the approach of two leading candidates for a ...

The original version of this story appeared in Quanta Magazine. String theory captured the hearts and minds of many physicists decades ago because of a beautiful simplicity. Zoom in far enough on a ...

During the latter part of the 20th century, string theory was put forward as a unifying theory of physics foundations. String theory has not, however, fulfilled expectations. That is why we are of the ...

String theory has long been presented as physicists' best candidate for describing the fundamental nature of the Universe. Yet, at the beginning of the 21st century, it became apparent that most ...