Today, we are going to learn some interesting mnemomic tricks using the celebrated Pythagorean Theorem from your young years at the school. We will be using some simple triangles to remember some of the wonderful formulae of Special Relativity. It … Continue reading

# amarashiki

In this last article dedicated to momenergy we are going to learn: 1st) How momenergy transform under Lorent transformations, i.e., the Lorentz transformations of momenergy. 2nd) Some extra stuff on relativistic energy and other alternative deductions of some formulae we … Continue reading

Imagine you own a set of n different particle species, and you make them to collide. In general, even in classical mechanics, you can get some particles loose their identities and become “new particles”. Suppose you make m different “new” … Continue reading

We have seen that space and time are merged into the spacetime in Special Relativity (SR). Morever, in a similar way, we have also deduced that momentum and energy are merged into an analogue concept: the momenergy. Mathematically, it … Continue reading

Suppose we get a beam made of massive particles. The rest mass (the names invariant mass or proper mass are also popular) is . The particle travels a distance L in its inertial frame. The particle has an energy E … Continue reading

We are going to develop the mathematical framework of vectors in (Minkowski) spacetime. Vectors are familiar oriented lines in 3d calculus courses. However, mathematically are a more general abstract entity: you can add, substract and multiply vectors by some number. … Continue reading

“(…)The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to … Continue reading

During the 19th century, the electromagnetic theory of Maxwell assumed that electromagnetic waves travelled in a medium called ether. The Michelson-Morley experiment was an experiment devoted to detect the ether. We can think about the electromagnetic waves like an analogue … Continue reading

Imagine the S’-frame moves at constant velocity (see the frames above this line): relative to the S-frame. In the S’-frame an object moves with acceleration QUESTION: What is the acceleration in the S-frame? Of course it has to be something … Continue reading

In our daily experience, we live in a “non-relativistic” world with a very high degree of accuracy. Thus, if you see a train departing from you ( you are at rest relative to it) with speed (in the positive direction … Continue reading