Tractability Benchmarks
Testing whether a log-space coordinate transform makes near-singular problems cheaper to solve. 7/8 benchmarks meet the script's own criterion; Bessel J0 needs 2.9x fewer evaluations but is about 9.6x less accurate.
Log-space transform: 7.7x fewer evaluations on Lane-Emden n=3The Tractability Conjecture
"Problems exist that are numerically intractable classically but tractable in NNC/GUD composite calculus."
This is a methodology claim, not a physics claim. We are not saying NNC reveals new physics. These runs test whether a change of coordinates gives computational savings for specific problem classes. None of the problems below is intractable classically; the classical runs all finish.
The Log-Space Transform
Approach
The bigeometric derivative measures multiplicative change, which suggests working in log coordinates. The benchmarks do not modify the equations: they transform coordinates, solve the SAME equation in u = ln x, and transform back.
Classical (x-space)
Lane-Emden has a 2/x coefficient (a regular singular point) at the origin:
The 2/x term forces small step sizes near x=0
Log-Space (u = ln x)
In log coordinates the 2/x coefficient is gone:
SAME equation in new coordinates; both runs start at x = 1e-6
Why This Can Help
For power laws on x > 0, is constant because it measures multiplicative rates of change: power laws are linear in log-space. The transform u = ln(x) maps x=0 to u = -infinity, so uniform steps in u are geometrically graded steps in x. It is a coordinate choice; it does not remove a physical singularity, and it does not help every problem (Bessel J0 below).
Benchmark Results
Measured Results
| Benchmark | Classical | Log-space | Reduction | Error (classical / log-space) | Accuracy ratio | Script criterion |
|---|---|---|---|---|---|---|
| Lane-Emden n=3 | 12,080 evaluations | 1,562 evaluations | 7.7x | 9.6e-4 / 3.2e-5 | 30x better | met |
| Lane-Emden n=4 | 12,086 evaluations | 1,496 evaluations | 8.1x | 4.0e-4 / 8.3e-5 | 4.8x better | met |
| Lane-Emden n=5 | 12,092 evaluations | 1,430 evaluations | 8.5x | 1.0e-1 / 1.0e-1 | not measured | met |
| Power-law n=-2 | 10,000 points | 100 points | 100x | 2.5e+0 / 1.1e-3 | 2218x better | met |
| Power-law n=-3 | 10,000 points | 100 points | 100x | 5.7e+0 / 4.5e-3 | 1263x better | met |
| Power-law n=-6 | 10,000 points | 100 points | 100x | 1.6e+1 / 2.8e-2 | 559x better | not demonstrated |
| Kolmogorov Cascade | 10,000 points | 100 points | 100x | 8.2e+0 / 0 | not measured | met |
| Bessel J0 | 12,182 evaluations | 4,262 evaluations | 2.9x | 4.9e-6 / 4.7e-5 | 9.6x worse | met |
Lane-Emden errors are relative errors in the first zero xi_1 against tabulated values; Lane-Emden n=5: n=5 has no finite first zero; the script records a placeholder error of 0.1 for both stable runs. Power-law errors are relative errors of a uniform-grid Simpson rule (classical) vs a log-uniform grid (transformed); the 10,000 vs 100 point counts are fixed by the script, not adapted. Kolmogorov: evaluates the identity D_BG[k^(-5/3)] = e^(-5/3); no numerical accuracy comparison.
ODE counts are solve_ivp right-hand-side evaluations. The classical x-space runs are capped at max_step = 0.01 by the script (about 2,000 RK45 steps over x up to 20, roughly 12,000 evaluations); the log-space runs are not capped. Much of the reduction comes from that cap, not from the 2/x term alone.
Benchmark Descriptions
1. Lane-Emden Equation (Stellar Structure)
Both solvers use the same adaptive integrator and tolerances; the log-space run solves and maps back.
2. Power-Law Integration
Integrating from x = 1e-4 to 10 on a uniform grid vs a log-uniform grid:
3. Kolmogorov Spectrum (identity check)
For on k > 0 the bigeometric derivative is a constant:
This row evaluates an identity; it is not a turbulence simulation and its "error" fields are not an accuracy comparison. The script flags it as tractable unconditionally.
4. Bessel J0 (the counter-case)
The log-space run takes 12,182 vs 4,262 evaluations (2.9x fewer) but its maximum error is 4.7e-5 vs 4.9e-6 classically: about 9.6x less accurate. Fewer evaluations is not the same as a better answer.
What Would Falsify This
For the tractability claim to be meaningful, there must be ways it could fail:
- 1.No work reduction: If the transform required the same or more evaluations, tractability would be falsified.Result: 2.9x-8.5x fewer ODE evaluations (see the max_step note above); the 100x point reduction is set by the script.
- 2.Accuracy loss: If less work came with worse error, the trade-off would not be favorable.Result: observed for Bessel J0; not measurable for Lane-Emden n=5 and Kolmogorov Cascade.
- 3.Instability: If the transformed runs were less stable, they would not be practically useful.Result: 8/8 stable (vs 8/8 classical).
- 4.Problem-specific: If it only worked for cherry-picked problems, it would not be a general methodology.Result: 7/8 meet the script's criterion; not demonstrated: Power-law n=-6. All eight are power-law or origin-singular problems chosen to suit log coordinates.
Reproduce These Results
# Clone the repository git clone https://github.com/DNYoussef/meta-calculus-portfolio cd meta-calculus-portfolio # Install dependencies pip install numpy scipy # Run benchmarks (writes results/tractability_benchmarks.json) python simulations/tractability_benchmarks.py # Expected evaluation/point counts (wall-clock times vary by machine): # Lane-Emden n=3: classical 12080 evaluations -> log-space 1562 evaluations (7.7x) # Lane-Emden n=4: classical 12086 evaluations -> log-space 1496 evaluations (8.1x) # Lane-Emden n=5: classical 12092 evaluations -> log-space 1430 evaluations (8.5x) # Power-law n=-2: classical 10000 points -> log-space 100 points (100x) # Power-law n=-3: classical 10000 points -> log-space 100 points (100x) # Power-law n=-6: classical 10000 points -> log-space 100 points (100x) # Kolmogorov Cascade: classical 10000 points -> log-space 100 points (100x) # Bessel J0: classical 12182 evaluations -> log-space 4262 evaluations (2.9x)
Mathematical Precedents
QFT Regularization
Dimensional regularization changes the framework to make divergent integrals finite. An analogy only: framework choice affects computability.
Distribution Theory
Dirac delta is undefined as a function but well-defined as a distribution. The right framework makes "impossible" objects tractable.
Tropical Geometry
Replacing (+, x) with (min, +) makes certain algebraic problems become linear. Framework choice enables new solution methods.