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equations:klein-gordon_equation

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$$( \partial _{\mu} \partial ^{\mu}+m^2)\Phi = 0 $$
–>Definitions#

- $\partial _{\mu} $ denotes the partial derivative and $\partial _{\mu} \partial ^{\mu}$ stands for a sum using the Einstein sum convention, i.e. $\partial _{\mu} \partial ^{\mu} = \partial _0 \partial^0 - \partial _1 \partial^1 -\partial _2 \partial^2 -\partial _3 \partial^3$.
- $m$ denotes the mass of the particle.
- $\Phi$ is either the wave function of the spin $0$ particle if we use the Klein-Gordon equation in a particle theory, or describes the spin $0$ field if we work in a field theory.

←-

The Klein-Gordon equation is the correct equation of motion that describes free spin $1$ particles.

Explanations in this section should contain no formulas, but instead colloquial things like you would hear them during a coffee break or at a cocktail party.

- A nice discussion can be found in chapter 3 of Klauber's Student Friendly QFT book
- For an elementary derivation of the Klein-Gordon equation see Physics from Symmetry by Schwichtenberg

The motto in this section is: *the higher the level of abstraction, the better*.

- Common Question 1

- Common Question 2

- Example1

- Example2:

equations/klein-gordon_equation.1520936299.txt.gz · Last modified: 2018/03/13 10:18 (external edit)

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