- #1
Shmi
- 12
- 0
In the very first example of Feynman and Hibb's Path Integral book, they discuss a free particle with
[tex]\mathcal{L} = \frac{m}{2} \dot{x}(t)^2[/tex]
In calculating it's classical action, they perform a simple integral over some interval of time [itex]t_a \rightarrow t_b[/itex].
[tex] S_{cl} = \frac{m}{2} \int_{t_b}^{t_a} \dot{x}(t)^2 \; dt = \frac{m}{2} \frac{(x_b - x_a)^2}{t_b - t_a}[/tex]
I don't see how that result follows! Is there some nifty integration by parts that I'm missing?
[tex]\mathcal{L} = \frac{m}{2} \dot{x}(t)^2[/tex]
In calculating it's classical action, they perform a simple integral over some interval of time [itex]t_a \rightarrow t_b[/itex].
[tex] S_{cl} = \frac{m}{2} \int_{t_b}^{t_a} \dot{x}(t)^2 \; dt = \frac{m}{2} \frac{(x_b - x_a)^2}{t_b - t_a}[/tex]
I don't see how that result follows! Is there some nifty integration by parts that I'm missing?