LOG#091. Group theory(XI).

Today, we are going to talk about the Lie groups and , and their respective Lie algebras, generally denoted by and by the physics community. In addition to this, we will see some properties of the orthogonal groups in euclidena … Continue reading

LOG#039. Relativity: Examples(III).

Example 1. Absorption of a photon by an atom. In this process, we have from momenergy conservation: If the atom is the rest frame, before absorption we get Description: an atom “a” at rest with mass absorbs a photon “b” … Continue reading

LOG#037. Relativity: Examples(I)

Problem 1. In the S-frame, 2 events are happening simultaneously at 3 lyrs of distance. In the S’-frame those events happen at 3.5 lyrs. Answer to the following questions: i) What is the relative speed between frames? ii) What is … Continue reading