Visible light is just a small part of a much of a much broader spectrum of electromagnetic radiation, ranging from radio waves at one end through microwaves, visible light and X Rays to gamma rays at the other end of the spectrum. All of these different and seemingly diverse types of radiation are the various […]

How far is it around the earth? More specifically, if I was to set off from here in Wokingham following a great circle route, how far would I have to travel before I found myself back here in Wokingham? Well, if you look it up on Google the circumference of the earth is near enough […]

  Introduction The quantisation of matter and of electric charge are simple concepts to grasp since they involve merely the absence or presence of a integer number of discrete particles.  Particles, like grains of sand, can simply be counted to give the total amount of matter in any given volume.  Electric charge is only a […]

The current received wisdom is that the universe began with a big bang some 13.7 billion years ago and that it has been expanding ever since.  This idea of an expanding universe begs the question where was the centre from which this big bang emanated, where is the point in the universe away from which […]

Here I take a look at the Rydberg formula in more detail and derive the Rydberg series, which is useful in calculating the change in energy level between any two states of the hydrogen atom and can be used to generate all of the other series:  Lyman, Balmer, Paschen, Brackett, Pfund, Humphreys etc.  I go […]

Louis de Broglie

Prince Louis Victor Pierre Raymond de Broglie was born in Dieppe on August 15th 1892.  De Broglie first studied history, but developed an interest in physics as a result of working with his older brother Maurice.  Maurice had been a naval officer where he worked on early radio systems for ship to ship and ship […]

Following Bohr’s model for the hydrogen atom Louis de Broglie suggested that the electron could be considered as a wave rather than a particle and proposed that the wavelength of such a wave was Planck’s constant divided by the linear momentum of the orbiting electron.   In effect he was restating Bohr’s adopted assumption that angular […]

Otto Stern and Walther Gerlach

This experiment is often cited as demonstrating that angular momentum is quantised.  In fact it does nothing of the sort, and indeed it clearly demonstrates that it is not, at least not in the way that physicists would have you believe. The Stern Gerlach experiment was first carried out by German physicists Otto Stern(1888-1969) and […]