(July 23, 2019 at 2:14 pm)LastPoet Wrote:(July 23, 2019 at 1:34 pm)polymath257 Wrote: 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.
Pity you weren't taught Einstein's theory of Acceleration Due To Panicking. I'm sure most of us have got bumps and bruises for ignoring that one.
Boru
‘I can’t be having with this.’ - Esmeralda Weatherwax