Table 1 List of symbols
| Symbol | Description |
|---|---|
| N, u, s | Population size, mutation rate, and mutation effect |
 | Number of individuals in class k at time t, steady-state value |
| λ = u/s, τ = ts | Rescaled mutation rate and time |
 | Population frequency in class k at time τ, steady-state value |
zτ,  | Abbreviation for x0(τ) and  |
 | Mean fitness:  |
 ,  | Deviations from steady state:  ,  |
| Sλ({zρ}) | Path integral action depending on the path {zρ} with 0 ≤ ρ ≤ τ. |
 ,  | Extremal action and the associated path depending on the endpoints zτ, z0 |
 | Long time limit of  with z = zτ |
| Pτ(zτ|z0) | Propagator from z0 to zτ in time τ |
| P(z) | Steady-state distribution of z |
| γ | Rate of the ratchet in units of s |
| σ2 | Variance of x0 depending on Ns and λ |
| ζ2 | Rescaled variance of x0 depending on λ only: ζ2 = Nseλσ2 |
 ,  | kth component of right and left eigenvectors with eigenvalue −i |
| ai(τ) | Projection of δxk on  |
| α | Parameter of the effective potential confining x0 (traditionally α = 0.5−0.6) |