(July 23, 2019 at 1:34 pm)polymath257 Wrote:(July 23, 2019 at 12:44 pm)comet Wrote: You also mentioned "energy is the Time component of ..." , whats that mean? energy is the time component?
A vector has components. So, for example, a vector in two dimensions has an x-component and a y-component. A vector in three dimensions has three components: x,y, and z. A vector in four dimensions has four components: x,y,z, and t.
So, in the energy-momentum 4-vector, the x,y, and z components are the amounts of momentum in the x,y, and z directions. The t component is the energy.
Now, truthfully, if you didn't know what a vector is, you don't have even enough *classical* physics to have a *basic* knowledge of physics, and thereby even a basic understanding of energy. And to have a *modern* view requires a LOT more than just some knowledge of vector calculus.
I wish I had a physics teacher like you. Mine just throwed stuff in the blackboard and ask about it. I never did homework, but I liked to read my books in the train ride after school. I was so tangled with a simple derivative that when I looked outside I saw my stop going backwards. In the panic I jumped out of the accelerating train resulting in some moderate pain. That,s momentum, gravity and poor decision making in a single lesson.
