Physics

Tensor Field

Jovan Stosic March 30, 2024

A tensor field is a mathematical object that assigns a tensor to each point in a space, such as a manifold or a vector space. Tensors are multidimensional arrays of numbers that represent certain geometric or physical properties. They generalize scalars (which are 0th-order tensors), vectors (1st-order tensors), and matrices (2nd-order tensors). A general tensor field can have components that vary in both magnitude and direction at each point in space. Unlike scalars and vectors, which have single numbers or arrows associated with each point, tensors can represent more complex relationships, such as stress, strain, curvature, or electromagnetic fields. For example, in general relativity, the metric tensor field describes the curvature of spacetime. In fluid dynamics, the stress tensor field describes how forces are distributed within a fluid. In materials science, the strain tensor field describes how materials deform under stress. In summary, a tensor field is a mathematical object that assigns a tensor to each point in a space, and a general tensor field can represent complex relationships or properties that vary across that space.

Tensor Field was last modified: March 30th, 2024 by Jovan Stosic

Temperature vs wind

Jovan Stosic March 30, 2024
  1. Temperature as a Scalar Field: Temperature is a scalar quantity, meaning it has magnitude but not direction. In a given region of space, temperature can vary from point to point, creating what is called a scalar field. Each point in space has a specific temperature value associated with it, but there is no directionality associated with those values.
  2. Wind as a Vector Field: Wind, on the other hand, is a vector quantity, meaning it has both magnitude and direction. Wind speed tells you how fast the wind is blowing, and wind direction tells you where it’s blowing from. Together, these two components create a vector field, where at each point in space, there is a vector representing the wind speed and direction.

So, in summary, temperature behaves as a scalar field because it only has magnitude, while wind behaves as a vector field because it has both magnitude and direction.

Temperature vs wind was last modified: March 30th, 2024 by Jovan Stosic

Inertial frame of reference

Jovan Stosic January 8, 2024

In classical physics and special relativity, an inertial frame of reference (also called inertial space, or Galilean reference frame) is a frame of reference not undergoing any acceleration.

https://en.wikipedia.org/wiki/Inertial_frame_of_reference#:~:text=In%20classical%20physics%20and%20special,reference%20not%20undergoing%20any%20acceleration.

Inertial frame of reference was last modified: January 8th, 2024 by Jovan Stosic

B2FH paper

Jovan Stosic April 18, 2023

The B2FH paper was a landmark scientific paper on the origin of the chemical elements. The paper’s title is Synthesis of the Elements in Stars, but it became known as B2FH from the initials of its authors: Margaret Burbidge, Geoffrey Burbidge, William A. Fowler, and Fred Hoyle. It was written from 1955 to 1956 at the University of Cambridge and Caltech, then published in Reviews of Modern Physics in 1957.

The B2FH paper reviewed stellar nucleosynthesis theory and supported it with astronomical and laboratory data. It identified nucleosynthesis processes that are responsible for producing the elements heavier than iron and explained their relative abundances. The paper became highly influential in both astronomy and nuclear physics.

https://en.wikipedia.org/wiki/B2FH_paper

B2FH paper was last modified: April 18th, 2023 by Jovan Stosic