Author archives: DIPC

The complementarity principle

The complementarity principle

PhysicsQuantum physics

By DIPC

Quantum mechanics was founded upon the existence of the wave–particle dualism of light and matter, and the enormous success of quantum mechanics, including the probability interpretation, seems to reinforce the importance of this dualism. But how can a particle be thought of as “really” having wave properties? And how can a wave be thought of […]

Superconductivity and the BCS theory

Superconductivity and the BCS theory

Condensed matterPhysics

By DIPC

The band theory of metals has been subjected to experimental tests many times and is now the accepted model of the behaviour of conductors and insulators. But it has to be modified when it comes to superconductivity. Electrical resistance is due to collisions of the electrons (whether treated as particles or waves) with impurities, imperfections […]

All-metal aromatic compounds

All-metal aromatic compounds

ChemistryCondensed matter

By DIPC

In the early days of organic chemistry, the word aromatic was used to describe fragrant substances such as benzene (from coal distillate), benzaldehyde (from cherries, peaches, and almonds), and toluene (from tolu balsam). It was soon realized, however, that substances classed as aromatic differed from most other organic compounds in their chemical behaviour. Today, the […]

Why do some materials conduct electricity and others don’t? (2): The band theory of solids

Why do some materials conduct electricity and others don’t? (2): The band theory of solids

Condensed matterPhysics

By DIPC

In 1928, just two years after the formulation of quantum mechanics, the German physicist Arnold Sommerfeld modified the classical free-electron model by treating the electrons according to quantum mechanics. But the new theory still contained the unrealistic assumption that the electrons do not interact with the charged lattice ions except to collide with them. As […]

Why do some materials conduct electricity and others don’t? (1): The classical free-electron model

Why do some materials conduct electricity and others don’t? (1): The classical free-electron model

Condensed matterPhysics

By DIPC

Electrical energy is now the dominant form of energy consumption in industrialized countries and is an essential element in the operation of many of the devices we use every day. For decades, one of the most poorly understood yet most practical properties of a piece of solid matter was its ability, or lack of ability […]

Einstein and quantum solids

Einstein and quantum solids

Condensed matterPhysics

By DIPC

One of the first recognized successes of the early quantum theory arose, not from the study of radiation, but from the theory of solids. Once again in the physics of the first half of the 20th century Albert Einstein was at the forefront; but this time the story is seldom told. After presenting the hypothesis […]

Clearly placed before the mathematical mind

Clearly placed before the mathematical mind

HistoryPhysics

By DIPC

We recently explored the concepts that Faraday introduced regarding the relationship between electricity and magnetism. In this article we focus on their treatment by Maxwell. The work of Oersted, Ampere, Henry, and finally Faraday had established two basic principles of electromagnetism: 1. An electric current in a conductor produces magnetic lines of force that circle […]

The sky is blue, clouds are white, and the transmission of light through dense media

The sky is blue, clouds are white, and the transmission of light through dense media

Condensed matterPhysics

By DIPC

Newton suggested that the apparent colours of natural objects depend on which colour is most strongly reflected or scattered to the viewer by the object. In general, there is no simple way of predicting from the surface structure, chemical composition, etc., what colours a substance will reflect or scatter. However, the blue colour of the […]