....^1.1

Quantities such as $Q$ and $W$ are often called process variables.

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... space''.^2.1

The term is probably due to Paul Ehrenfest who in his classical book on Statistical Mechanics refers to $\mu$-space, or ``molecular'' space as opposed to $\Gamma$, or ``gas'' space (see Chapter 3 below).

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... reads^3.1

In an MD simulation not only the total energy but also the total momentum $\vec{P}$ is conserved; this should be kept in mind when comparing simulation results to theoretical statements. Actually, the four conditions $E \epsilon (E_{0}-\Delta E,E_{0})$ and $\vec{P}=const$, would define a $3N-3$-dimensional spherical shell in velocity space. However, for sufficiently numerous particles ($N \geq 100$) this detail may be neglected, and we can base the argumentation just on the condition $E \approx E_{0}$ (with a $3N$-dimensional shell).

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... size^3.2

A particularly powerful formulation of classical mechanics, known as Hamilton's formalism, makes use of the variables $\vec{q},\vec{p}$ (position and momentum) in place of $\vec{r},\vec{v}$ (position and velocity.) In this notation the phase space cells have the size $h \equiv \Delta q \Delta p$.

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