In the present context, the Markovian approximation consists of an approximate treatment of certain interference terms valid for small separation between the qubits.
Therefore, in the limit of small particle approximation, the dipolar approximation consists in considering only the a1 and b1 (called dipolar electric and magnetic) terms of the series in Eq. (3).
The lower approximation consists of all objects that definitely belong to the set, and the upper approximation contains all objects that possibly belong to the set.
The spline approximation consists of two off-step points (x_{l pm 1/2}) and a central point (x_{l}), (l = 0,1,2,ldots,N) with two end points (x_{0}) and (x_{N + 1}), where (h_{l} = x_{l} - x_{l - 1}), (l = 1,2,ldots,N + 1), be the mesh size in x-direction and (k = t_{j + 1} - t_{j} > 0), (j = 0,1,2,ldots ) be the mesh spacing in t-direction.
The stochastic shielding approximation consists of neglecting fluctuations in the dynamics associated with edges in the graph not directly affecting the observable states.
The standard diffusion approximation consists of diffusion equation of the form (A.3) − ∇ ⋅ κ DA ∇ Φ 0 (r ) + μ a Φ 0 (r ) = 0, and the Robin boundary condition is of the form (A.4) Φ 0 (r ) + 1 2 γ n κ DA A ∂ Φ 0 (r ) ∂ n ^ = I s γ n, where γ n is a dimension dependent constant (γ2 = 1/ π, γ3 = 1/4) and I s is an inward directed diffuse boundary current at the source position [ 36].
The stochastic shielding approximation consists of neglecting fluctuations associated with edges in the graph not directly affecting the observable states.
The mean field approximation consists of two mutually coupled partial differential equations featuring (i) the probability distribution for residual supersaturation and (ii) the mean number density of particles for each size and supersaturation from which all average properties and fluctuations can be calculated.
This approximation consists in truncating the spectral decomposition of the contact interaction matrix at the first spectral component, namely U a, b) ≈ - h(a) h(b), where h(a) indicates the component of the main eigenvector of U a, b) corresponding to amino acid a, which we call the interactivity of amino acid a.
