### What's Up

### Most Read Articles

- Riemann curvature tensor and Ricci tensor for the 2-d surface of a sphere
- Christoffel symbol exercise: calculation in polar coordinates part II
- Riemann curvature tensor part I: derivation from covariant derivative commutator
- Metric tensor exercise: calculation for the surface of a sphere
- Christoffel Symbol or Connection coefficient

- Details
- Category: Latest Readings
- Hits: 5870

An interesting paper on the long an tortuous Einstein's journey through the tensors.

"For much of the period between 1912 and 1916 he was truly lost in the tensors, quite completely on the wrong path, accompanied by erroneous reasons he claimed to be fundamental.

And yet, quite singularly, in the course of a month he abondoned his errors and their justifications.

The moral, perhaps, is that a certain fickleness is more conducive to theoretical progress than is any abundance of conceptual clarity -- at least if one is Einstein."

Lost in the Tensors: Einstein's Struggles with. Covariance Principles, 1912-1916

- Details
- Category: Latest Readings
- Hits: 5931

I have recently discovered this you tube channel Dr PhysicsA, dedicated to the introduction/explanation of many physics topics.

I really enjoyed watching these videos on General Relativity and would like to share them with you:

- Details
- Category: Latest Readings
- Hits: 5659

No doubt that you will really enjoy the reading of this very well written little book *Seven Brief Lessons on Physics* from Carlo Rovelli, currently directing the quantum gravity research group of the Centre de Physique Théorique in Marseille, France

The brief lessons cover seven areas in modern physics — relativity, quantum mechanics, the structure of the universe, particle physics, quantum gravity, probability and black holes, and finally, how all these topics relate to us mere mortals.

Read more: Seven Brief Lessons on Physics from Carlo Rovelli

- Details
- Category: Latest Readings
- Hits: 5578

In this short volume, Professor Richard P. Feynman delves into Einstein's special relativity. That's a very entertaining and scintillating book that i would advise anyone to read!

Chapter 3 is dedicated to a general introduction to special Relativity and to Lorentz transformations

Chapter 4 introduces the notion of relativistic energy

Chapter 5 describes the spacetime notion

And finally Chapter 6 takes the curvature of spacetime as principal study object.