Category archives: Physics

Quantum Thermodynamics VI: Negative absolute temperatures in optical lattices

Quantum Thermodynamics VI: Negative absolute temperatures in optical lattices

PhysicsQuantum physics

By Daniel Manzano

As we have discussed in our previous post, there is an important debate in the scientific community regarding the existence of negative absolute temperatures. The debate is not over, and both sides have valuable arguments, but in any case, one thing has already been proved. If negative absolute temperatures are real, the requirement to achieve […]

How you grow graphene on d-metals key to get spin-polarized electrons

How you grow graphene on d-metals key to get spin-polarized electrons

Condensed matterMaterialsPhysics

By DIPC

Graphene is a material with outstanding electronic characteristics. Many of them arise from the cone-like dispersion of charge carriers near the Fermi level (at which the occupation probability of energy levels is 0.5), where electrons behave as relativistic Dirac fermions, i.e., as if they had no mass. This excellent video from toutestquantique.fr summarizes them very […]

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

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

PhysicsTheoretical physics

By Carlos Shahbazi

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 context of String Theory and M-Theory compactifications. As it is well known, to be well-defined […]

From gas to cash. The unexpected applications of statistical mechanics

From gas to cash. The unexpected applications of statistical mechanics

HistoryPhysics

By Pablo Rodríguez Sánchez

Mechanics and thermodynamics are two of the main pillars of physics. Mechanics, the branch of physics that studies movement, is considered to be well established since the publication of Isaac Newton’s Philosophiæ Naturalis Principia Mathematica (1687). Thermodynamics, the science dealing with heat and temperature, enjoyed its golden age in the 19th century, and was the […]

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

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

PhysicsTheoretical physics

By Carlos Shahbazi

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 mathematical and the physics point of view, not only in String Theory. For example, differential geometry […]

How to measure tiny temperature differences using a Josephson junction

How to measure tiny temperature differences using a Josephson junction

Condensed matterMaterialsPhysicsQuantum physicsTheoretical physics

By DIPC

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, known as normal metals, behave in this way. The behaviour of another class of metals and […]