# Haven't got time for conservation

Consider a system of $$N$$ particles whose coordinates are $$\mathbf{r} = \{r_i^x, r_i^y, r_i^z\}$$, and whose velocities are $$\{\dot{\mathbf{r}}_i\}$$.

Each pair of particles $$\left(i, j\right)$$ interacts through a potential $$V\left(\mathbf{r}_i, \mathbf{r}_j\right)$$ which has no direct dependence on time. As the system evolves in time, which of the following bulk quantities must be conserved?

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