Architecture ideas

Attention variants, state-space and recurrent cells, normalization and token-mixing schemes — each tested against the standard block it replaces.

Unverified 2026

Hierarchical B-spline sparse-grid front end

Replace a dense tensor-product positional encoding or first MLP layer with a hierarchical sparse-grid B-spline feature map. The network evaluates only localized basis functions indexed by multi-levels with bounded total level, reducing feature count while retaining high-order approximation for functions with mixed derivative regularity. The basis can initially be fixed and later fine-tuned jointly with the downstream network.

Useful6/10
Difficulty5/10
Novelty6/10
Paper: A hierarchical sparse-grid particle method for the Vlasov--Poisson system arXiv:2607.19898
Unverified 2026

Anisotropic Anharmonic Diffusion Layer

Insert a learnable semigroup layer that evolves features according to a positive operator combining frequency damping and spatially varying confinement. Unlike isotropic Gaussian smoothing, the layer can damp selected frequencies differently along different axes and can suppress activations in learned spatial regions, while the positive-semigroup construction prevents amplification.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: Sharp Time-Decay Estimates for Fractional Heat Semigroups Associated with Polynomial Anharmonic Oscillators arXiv:2607.17580
Unverified 2026

Second-Order Sinh-Gordon Implicit Layer

Insert a differentiable implicit layer that maps boundary features to an interior latent field by solving a discrete sinh-Gordon equation. The paper's second-order convergence result motivates using a symmetric five-point discretization and a damped Newton solve rather than asking a neural network to learn the entire interior field directly.

Useful6/10
Difficulty6/10
Novelty7/10
Paper: Approximation of solutions of the sinh-Gordon equation $Δu -\sinh(2u)=0$ by hyperbolic orthogonal ring patterns arXiv:2607.14348
Unverified 2026

Active-Set Constraint Projection Layer

Replace generic projected-gradient iterations for equality-plus-bilateral constraints with an active-set semismooth Newton layer. Each iteration fixes currently active lower and upper bounds and solves one structured saddle-point system, potentially converging in a few iterations when only a small subset of constraints is active.

Useful6/10
Difficulty6/10
Novelty6/10
Paper: Duality Framework for Flux Constrained Flow in Porous Media: Analysis and Numerics arXiv:2607.13256
Unverified 2026

SBP Energy-Stable Sequence Mixer

Replace a dense token-mixing matrix in a sequence model with a fixed or learnable SBP derivative operator D=P^{-1}Q. The discrete integration-by-parts identity makes the interior mixing energy-neutral or boundary-dissipative, reducing exploding activations in deep residual stacks while preserving directional information along the sequence.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: Gaussian FSBP operators: Comparison and application to numerical methods for hyperbolic conservation laws arXiv:2607.13224
Unverified 2026

Endpoint-transformed Hermite feature layer

Replace ordinary Fourier, polynomial, or raw-coordinate features for a bounded scalar coordinate with Hermite functions evaluated after a monotone endpoint transform. The transform sends endpoint singularities to localized tails on the real line, while a learnable scale controls how many Hermite modes are needed. This is suited to coordinate MLPs, neural operators, and implicit fields whose targets have square-root, logarithmic, boundary-layer, or derivative singularities.

Useful6/10
Difficulty4/10
Novelty7/10
Paper: Hermite spectral approximation for functions with endpoint singularities using exponential transforms arXiv:2607.12648
Unverified 2026

Algebraic-Invariant Residual Layer

Represent a rational-like feature transformation with an auxiliary state y constrained by polynomial equations G(x,y)=0, and update x and y jointly along the tangent space of that constraint manifold. This creates residual blocks in which nonlinear feature identities remain consistent over many layers or time steps, reducing auxiliary-variable drift and potentially stabilizing rational activations and implicit recurrent dynamics.

Useful6/10
Difficulty5/10
Novelty8/10
Paper: Algebraic Invariant Quadratization Schemes for Cahn--Hilliard Equations arXiv:2607.11569
Unverified 2026

Log-Fractional Scale-Derivative Layer

Add a feature transformation that approximates the derivative of a fractional diffusion operator with respect to its order. Instead of only smoothing features with one fractional order, the layer exposes whether a feature changes rapidly across spatial scales, which can help with textures, edges, and multiscale patterns.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: Regularity for the fractional logarithmic $p$-Laplacian arXiv:2607.11462
Unverified 2026

Legendre-polynomial feature trunk

Construct a reusable ReLU trunk that emits approximate univariate powers or Legendre-polynomial features for each input coordinate, then combine them with a linear or low-rank polynomial head. This gives a compact explicit basis for smooth functions and can replace a large generic MLP in low-dimensional scientific regression or serve as a frozen or partially trainable front-end.

Useful6/10
Difficulty6/10
Novelty6/10
Paper: Approximation of Analytic Functions by ReLU Neural Networks with Adjustable Depth and Width arXiv:2607.10589
Unverified 2026

Depth-first analytic MLP scaling

For smooth coordinate-based regression, replace a width-heavy MLP with a deliberately narrow but deeper ReLU network and choose depth and width using the paper's analytic-function approximation law. The hypothesis is that, at fixed parameter count, increasing depth gives a larger reduction in approximation error than increasing width when the target is close to analytic.

Useful6/10
Difficulty4/10
Novelty7/10
Paper: Approximation of Analytic Functions by ReLU Neural Networks with Adjustable Depth and Width arXiv:2607.10589
Unverified 2026

Block-Probed Rational Spectral Layer

Replace a polynomial graph filter or repeated matrix multiplications in a graph neural network with a small rational filter evaluated at several shifts. Treat the incoming feature matrix as a block of probes rather than processing scalar probe vectors independently, allowing one set of shifted solves to expose multiple spectral directions simultaneously. The expected gain is higher approximation quality at the same number of operator applications, especially when the target filter has sharp or…

Useful6/10
Difficulty6/10
Novelty6/10
Paper: Convergence analysis of a nonlinear eigensolver based on rational approximation of the resolvent arXiv:2607.10377
△ Mechanism confirmed, baseline not beaten 2026

Symplectic Recurrent Block

Use a symplectic Hamiltonian update as a recurrent or state-space neural block, preserving a learned modified energy across many layers or time steps. This targets residual and recurrent architectures where ordinary Euler updates accumulate drift during long rollouts.

Useful6/10
Difficulty5/10
Novelty5/10
Paper: Backward error analysis for matrix discretizations of 2-D Euler equations arXiv:2607.09549
✓✓ Beats tuned baseline 2026

Local Characteristic Residual Gating

Transform local neural residuals into the Ripa model's characteristic coordinates before spatial aggregation, apply a mode-dependent gate based on neighboring characteristic jumps, and transform back. This lets the model damp oscillatory acoustic or equilibrium-mode corrections near discontinuities without globally smoothing every feature.

Useful6/10
Difficulty6/10
Novelty6/10
Paper: Fifth-Order Well-Balanced Path-Conservative A-WENO Scheme for the Ripa Model arXiv:2607.09293
✗ Mechanism failed 2026

Resolvent Fractional-Power Layer

Parameterize a learned feature-space operator as accretive but not necessarily symmetric, then apply its fractional power through a finite positive mixture of shifted resolvents. This provides a matrix-function layer that can represent directional and rotational interactions while avoiding unstable eigendecomposition of nonnormal matrices.

Useful6/10
Difficulty6/10
Novelty7/10
Paper: Functions and Means of Accretive Operators arXiv:2607.09152
✗ Mechanism failed 2026

Rank-Adaptive Tensor-Train MLP

Replace a large dense layer whose input and output dimensions factor into multiple modes by a TT-matrix whose parameters are stored as a chain of small cores. Periodically apply TT-SVD rounding to remove weak singular directions and keep the representation within a prescribed approximation error. This transfers the paper's central computational principle—perform tensor-product contractions directly in compressed form—to neural network layers.

Useful6/10
Difficulty5/10
Novelty4/10
Paper: A Tensor-Train Discontinuous Galerkin Method for the Vlasov-Maxwell System arXiv:2607.08936
✗ Mechanism failed 2026

Periodic CMV Unitary Recurrent Layer

Replace a dense recurrent transition matrix with a periodic CMV-style product of alternating local 2x2 unitary cores. The transition is exactly norm-preserving, has O(n) trainable parameters under periodic tying, and can be applied through local factor operations rather than stored as an n-by-n matrix. Use turnover refactorization when changing the ordering or boundary connection of cores, enabling a compact cyclic unitary state-space layer.

Useful6/10
Difficulty5/10
Novelty5/10
Paper: Fast computation of eigenvalues of periodic CMV matrices arXiv:2607.06400
✗ Mechanism failed 2026

Adaptive CUR Neural Layer

Replace a dense weight matrix by a cross approximation built from selected rows and columns rather than by a conventional truncated SVD. Periodically refresh the selected indices using residual leverage scores, warm-starting from the previous factorization so that the compressed layer can track weight changes during fine-tuning.

Useful6/10
Difficulty5/10
Novelty5/10
Paper: A Sub-linear Low-Rank Solver for Poisson's Equation using Machine Learning Frameworks for GPU Acceleration arXiv:2607.06021
✓✓ Beats tuned baseline 2026

Critical-Tail Multiscale Mixer

Add a fixed or weakly parameterized residual mixer whose interaction between sequence positions at distance \(r\) is proportional to \(1/(r\log^2 r)\). Instead of truncating the kernel at a short radius, represent its heavy tail with dyadic distance bands and compute each band using prefix sums or block pooling, giving every token access to arbitrarily distant context at roughly \(O(L\log L)\) cost.

Useful6/10
Difficulty5/10
Novelty6/10
Paper: Long-range interactions and Anderson localisation for one-dimensional high-contrast resonator chain arXiv:2607.04971
✗ Mechanism failed 2026

Unassembled Adaptive Cell Neural Network

Represent every mesh interface degree of freedom by one feature copy per incident cell, and apply local neural blocks directly to these cell tensors. Enforce inter-cell consistency with valence-weighted averaging only after selected layers or hierarchy transitions, avoiding repeated construction of a global sparse graph or assembled feature vector. This is suited to adaptive quadtrees, octrees, and finite-element neural operators.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: Coalesced Matrix-Free Geometric Multigrid on Persistent Cell-Wise Storage arXiv:2607.03413
✓✓ Beats tuned baseline 2026

Singularity-Enriched Neural Ansatz

Add an explicit local power-law singular basis to a neural field near mixed Dirichlet-Neumann junctions, allowing the neural network to learn only the smoother remainder. Use the predicted or fitted singular exponent to concentrate collocation points near the junction. This directly targets the regularity bottleneck identified by the paper, where increasing polynomial degree or network capacity cannot overcome a convergence cap under uniform resolution.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: A Unified CutFEM Formulation for Finite-Strain Elasticity: Energy Minimisation and Corner Singularities arXiv:2607.02334
✗ Mechanism failed 2026

Fourier-Calibrated Nonlocal Feature Gradient

Augment a CNN with a nonlocal feature-gradient branch that compares each feature vector with a kernel-weighted neighborhood rather than using only pointwise or local convolutional interactions. Regularize this branch using the paper's Fourier multiplier energy, which penalizes feature oscillations according to the kernel spectrum and approaches an ordinary local-gradient operator as the interaction radius tends to zero.

Useful6/10
Difficulty4/10
Novelty6/10
Paper: A Variational Nonlocal Phase-Field Model for Dynamic Fracture in Elastic Solids arXiv:2607.01881
✗ Failed on benchmark 2026

GQL Safe Residual Layer

Insert a scalar flux-correction-style limiter after a neural operator predicts a conservative state or residual. Interpolate between a known-admissible baseline state and the learned high-order candidate, choosing the largest coefficient that satisfies a geometric family of linear inequalities encoding positive density, positive pressure, and subluminal velocity. This retains as much of the neural prediction as possible instead of independently clipping physical variables.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: GQL-Based Physical-Constraint-Preserving High-Order Finite Difference Schemes for Special Relativistic Hydrodynamics in Arbitrary Dimensions arXiv:2606.31992
✗ Mechanism failed 2026

Dual-Rail Ratio Arithmetic Layer

Replace scalar neural activations by pairs of nonnegative channels whose ratio represents the signed or unsigned activation. Implement multiplication and addition through pair algebra, and renormalize each pair because the representation is invariant under multiplying both rails by the same positive scalar. This creates an explicitly bounded, cancellation-aware arithmetic layer for deep multiplicative MLPs, rational networks, and neural fields.

Useful6/10
Difficulty5/10
Novelty7/10
Paper: Instantaneous arithmetic computation via ratio-encoding in chemical reaction networks arXiv:2608.26305
✗ Mechanism failed 2026

Truncated-Fourier Domain Pooling

Replace ordinary masked mean pooling with a Fourier-compressed quadrature operator for arbitrary two-dimensional or three-dimensional domains. The geometry is preprocessed once into reusable grid weights, allowing every channel and every training example using the same domain to be pooled without boundary-area bias.

Useful6/10
Difficulty3/10
Novelty7/10
Paper: "Truncated Fourier Filtering" method for fast and high-order evaluation of integrals and convolutions in general domains arXiv:2608.25264