Statistical Mechanics operators
20 operators in the statistical_mechanics category of the live registry. Compose them in a contract or call POST /api/zeq/compute — KO42 is always on, plus up to three more per call.
How it computes: dedicated closed-form solver solveSM — real equations over CODATA-2018 constants; where an operator needs a series/matrix/field a scalar cannot express, it refuses honestly. See the solvers.
| Operator | Description | Equation |
|---|---|---|
EQP1 | Equipartition theorem: each quadratic degree of freedom carries a mean energy of ½k_BT, so a system with f quadratic DOF has ⟨E⟩ = (f/2)k_BT. | ⟨E⟩ = (f/2) k_B T |
MBS1 | Maxwell–Boltzmann speed distribution characteristic speeds: most-probable √(2kT/m), mean √(8kT/πm) and root-mean-square √(3kT/m) for an ideal gas at temperature T. | v_rms = √(3k_BT/m) |
NE1 | Point kinetics neutron equation: rate of change of neutron population with delayed neutron precursors. | \frac{dn}{dt} = (k-1)\frac{n}{\ell} + \sum_i \lambda_i C_i |
NE10 | Four-factor formula: infinite multiplication factor from reproduction, fast fission, resonance escape, and thermal utilization. | k_\infty = \eta f p \epsilon |
NE11 | Effective multiplication with non-leakage probability for finite reactor geometry. | k_{eff} = k_\infty P_{NL} |
NE12 | Buckling equation: geometric condition for criticality balancing neutron production and leakage. | B^2 = \frac{k_\infty - 1}{L^2 + \tau} |
NE13 | Diffusion length: characteristic distance a thermal neutron diffuses before absorption. | L = \sqrt{\frac{D}{\Sigma_a}} |
NE14 | Reactor power from neutron flux, fission cross-section, energy per fission, and volume. | P = \Phi\Sigma_f E_f V |
NE15 | Heat generation rate distribution in a cylindrical reactor core. | q''' = q_0 \cos\frac{\pi z}{H}J_0(2.405 r/R) |
NE16 | Thermal efficiency of a heat engine as one minus cold-to-hot temperature ratio. | \eta_{th} = 1 - \frac{T_C}{T_H} |
NE17 | Coolant mass flow rate required to remove reactor heat at given temperature rise. | \dot{m} = \frac{Q}{c_p \Delta T} |
NE2 | Delayed neutron precursor equation: production from fission minus decay for reactor kinetics. | \frac{dC_i}{dt} = \beta_i\frac{n}{\ell} - \lambda_i C_i |
NE3 | Effective multiplication factor: ratio of neutrons produced to neutrons lost in a reactor. | k_{eff} = \frac{\text{neutrons produced}}{\text{neutrons lost}} |
NE4 | Reactivity: fractional departure of multiplication factor from unity. | \rho = \frac{k-1}{k} |
NE5 | Reactor period: e-folding time for neutron population change. | T = \frac{\ell}{(k-1)(1-\beta)} |
NE6 | Macroscopic cross-section: number density times microscopic cross-section for neutron interactions. | \Sigma = N\sigma |
NE7 | Neutron flux: product of neutron density and speed, measuring interaction rate intensity. | \Phi = nv |
NE8 | Reaction rate: macroscopic cross-section times neutron flux for nuclear reaction rates. | R = \Sigma\Phi |
NE9 | Reproduction factor eta: average neutrons produced per absorption in fuel. | \eta = \frac{\nu\Sigma_f}{\Sigma_a} |
XI0 | Bosonic partition function: product over states of the geometric series factor. | φ × ∑min(I(p), I(¬p)) |
Compute one — a real call
Ask the operator which inputs it needs (the honesty contract refuses empty inputs rather than inventing them):
curl -sS -X POST https://zeqsdk.com/api/zeq/operator-spec \
-H "Content-Type: application/json" \
-d '{"operator":"EQP1"}'
See also
- The solvers — the coverage map and the ODE fallback
- The honesty contract — compute, ask, or refuse
- All operator categories