# Category Archives: Theoretical physics

## How to study magnetic Weyl fermions experimentally

Imagine there exist a material in which an electron could be split into two quasiparticles. These two quasiparticles both would carry electric charge, move in opposite directions but could not move backwards. Furthermore these quasiparticles would be massless. And […]

## On the spin geometry of String Theory

The purpose of this note is to introduce the reader to the notion of Lipschitz structure and its potential applications to the spin geometry required to globally formulate string theory and supergravity on a differentiable manifold. . Spinors are a crucial […]

## The geometry of String Compactifications (III): exploring the Calabi-Yau manifold

In the previous articles (I, II), we have characterized the simplest class of supersymmetric heterotic compactification backgrounds. In particular, we have finished the second article with the following result:. There is a class of admissible Heterotic internal manifolds characterized as […]

## The geometry of String Theory compactifications (II): finding the Calabi-Yau manifold

This is the second of the series of articles on the geometry of String Theory compactifications. Before reading this note, the interested reader may want to read the first note, where the concept of compactification background is introduced in the […]

## The geometry of String Theory compactifications (I): the basics.

This is first of a series of notes on the geometry of String Theory compactifications. The space-time in String Theory is often described by means of a mathematical object called manifold . Manifolds are very important objects from the […]

## How to measure tiny temperature differences using a Josephson junction

At low temperatures, the resistivity of a metal (the inverse of its conductivity) is nearly constant. As the temperature of a material is lowered and as we approach absolute zero the resistivity should approach a constant value. Many metals, […]

## Unveiling the origin of the record superconductivity

Achieving room temperature superconductivity is among the most pursued but elusive goals of scientists. A paper uploaded to the arXiv in December 2014 claims to have observed superconductivity as high as 190 K in hydrogen sulfide at high pressure, […]

## Supergravities

Authors:. Pablo Bueno holds a degree in physics (University of Oviedo), a MSc in theoretical physics (Autonomous University of Madrid) and is currently completing his PhD at the Institute for Theoretical Physics UAM-CSIC. He has also been a visiting graduate […]