{ "paper_id": "moe-pot", "paper_title": "MoE-POT: Mixture-of-Experts Operator Transformer for Large-Scale PDE Pre-Training", "D1": [ { "id": "moe-pot-D1-001", "claim": "Model architecture (size-invariant, confirmed by Table 5): N_r=16 routed experts, N_s=2 shared experts, Top-K=4, total 6 activated experts per input (4 routed + 2 shared); N_r, N_s, K invariant across Tiny/Small/Medium", "source": "Section 4 (lines 128, 134, 142), Section 1 (line 26), Section 3.2 (lines 81-83), Table 5" }, { "id": "moe-pot-D1-002", "claim": "Per-size attention dimension (Table 5): attention_dim=512 (Tiny) / 1024 (Small) / 1024 (Medium)", "source": "Table 5 (Appendix B.3)" }, { "id": "moe-pot-D1-003", "claim": "Per-size MLP hidden dimension (Table 5): mlp_dim=512 (Tiny) / 1024 (Small) / 2048 (Medium)", "source": "Table 5 (Appendix B.3)" }, { "id": "moe-pot-D1-004", "claim": "Per-size transformer layers (Table 5): num_layers=4 (Tiny) / 6 (Small) / 8 (Medium)", "source": "Table 5 (Appendix B.3)" }, { "id": "moe-pot-D1-005", "claim": "Per-size attention heads (Table 5): num_heads=4 (Tiny) / 8 (Small) / 8 (Medium)", "source": "Table 5 (Appendix B.3)" }, { "id": "moe-pot-D1-006", "claim": "Per-size total parameters (Table 5): 30M (Tiny) / 166M (Small) / 489M (Medium)", "source": "Table 5, Section 5 (line 188)" }, { "id": "moe-pot-D1-007", "claim": "Activated params (T/S/M): 17M / 90M / 288M. Note: Section 5 body text says 188M for Medium but Table 3 and Table 5 consistently show 288M — the 188M value is a typo in the MoE-POT paper", "source": "Table 5, Table 3, Section 5 (line 188)" }, { "id": "moe-pot-D1-008", "claim": "Pre-training config: Adam optimizer (β1=0.9, β2=0.9), lr=1e-3, One-cycle schedule, weight_decay=1e-6, 1000 epochs (200 warmup), batch_size=20 on 8x RTX 4090 (24GB), T=10 input timesteps, load_balance_weight w_bal=0.1, dataset_sampling_weight w_k=1", "source": "Section 5 (line 180), Section B.3 (lines 401-403), Section 4 (line 160)" }, { "id": "moe-pot-D1-009", "claim": "Fine-tuning config: lr=1e-3, One-cycle schedule, 200 epochs (40 warmup), router-gating network parameters frozen, only expert networks updated", "source": "Section B.3 (line 408), Section 5.1 (line 192)" }, { "id": "moe-pot-D1-010", "claim": "Downstream task config: lr=1e-3, One-cycle schedule, 500 epochs (100 warmup)", "source": "Section 5.2 (line 198), Section B.3 (line 408)" }, { "id": "moe-pot-D1-011", "claim": "Data preprocessing: spatial resolution H=128 (lower-res upscaled, higher-res downscaled), patch_size P=8 (Conv2D kernel PxP stride P), padding_constant=1 for unused channel entries", "source": "Section B.1 (lines 373-375), Section B.3 (line 403), Section C.1 (line 500)" }, { "id": "moe-pot-D1-012", "claim": "Pre-training dataset splits (train/test): FNO-NS(1e-5)=1000/200, FNO-NS(1e-3)=1000/200, PDEBench-CNS(0.1,0.01)=9000/200, PDEBench-SWE=900/60, PDEBench-DR=900/60, CFDBench=9000/1000; total 6 datasets from 3 benchmark collections", "source": "Table 6, Section 5 (line 178)" }, { "id": "moe-pot-D1-013", "claim": "Downstream dataset splits (train/test): NS(1e-4)=2000/200, CNS(1,0.01)=2000/200, PDEArena=2000/200", "source": "Table 7" }, { "id": "moe-pot-D1-014", "claim": "Dataset mixture counts (Appendix C.5 negative transfer analysis): 6-dataset (base: NS(1e-5), NS(1e-3), CNS(0.1,0.01), SWE, DR, CFDBench); 10-dataset (base + NS(1e-4), CNS(1,0.1), 2x PDEArena NS tasks); 12-dataset (10-set + CNS(1,0.01), CNS(0.1,0.1))", "source": "Section C.5 (lines 579-581)" }, { "id": "moe-pot-D1-015", "claim": "N_r (routed experts per layer) ablation: tested [8, 16, 32], selected 16 — error stable when N_r sufficiently large, balance of performance and computational cost", "source": "Table 4, Section 5.6 (line 235)" }, { "id": "moe-pot-D1-016", "claim": "Top-K ablation: tested [1, 2, 4], selected 4 — larger K reduces error with diminishing returns, 4 is optimal trade-off", "source": "Table 4, Section 5.6 (line 235)" }, { "id": "moe-pot-D1-017", "claim": "Number of heads h ablation: tested [2, 4, 8], selected 4 — minimal impact on error but affects computational cost", "source": "Table 8, Section C.1 (line 500)" }, { "id": "moe-pot-D1-018", "claim": "Patch size P ablation: tested [4, 8, 16], selected 8 — medium patch sizes reduce error, 8 chosen for optimal performance", "source": "Table 8, Section C.1 (line 500)" }, { "id": "moe-pot-D1-019", "claim": "Few-shot sample sizes — in-distribution (NS(1e-4)): [16, 32, 64, 128, 512, 2000]; models fine-tuned 500 epochs at each sample size", "source": "Table 13, Section C.4 (line 557)" }, { "id": "moe-pot-D1-020", "claim": "Few-shot sample sizes — out-of-distribution (Wave-Layer): [16, 32, 64, 128]; models fine-tuned 500 epochs at each sample size", "source": "Table 14, Section C.4 (line 557)" }, { "id": "moe-pot-D1-021", "claim": "Classification emergence eval epochs: [50, 150, 250] — router classification accuracy tracked over pre-training to measure emergence of dataset identification capability", "source": "Table 16, Section C.6 (line 599)" }, { "id": "moe-pot-D1-022", "claim": "Poseidon baseline activated params (used in Appendix C.2.2 comparison): Poseidon-T=21M, Poseidon-B=158M", "source": "Table 10, Section C.2.2" } ], "D2": [ { "id": "moe-pot-D2-001", "claim": "Balanced Data Sampling Probability: p_k = w_k / (K * |D_k| * sum_{j=1}^{K} w_j), where w_k is importance weight (w_k=1 for all datasets), |D_k| is dataset size, K=6 datasets. Ensures proportional representation of datasets with fewer samples.", "source": "B.1" }, { "id": "moe-pot-D2-002", "claim": "Noise Injection for Denoising Pre-training: epsilon ~ N(0, epsilon_bar * ||u^{ Noise Injection -> Patchification with Learnable Positional Encoding -> Temporal Aggregation with Fourier Features -> Multi-head Fourier Layer (AFNO-style frequency-domain MLP) -> MoE Router Gating (Softmax over CNN routing logits) -> MoE TopK Expert Selection -> MoE Output Aggregation (shared experts average + weighted routed experts) + Load Balancing Loss (CV-based auxiliary) -> Final Training Loss (MSE + per-layer load balance) -> Auto-regressive Inference Rollout (no noise, sliding window T=10).", "source": "Section 4 (derived from D2 ordering_before/ordering_after annotations)" }, { "id": "moe-pot-D4-002", "claim": "Router interpretability classification pipeline (Section B.4): Step 1 — Compute average expert distribution Y_i for each pre-training dataset i from full softmax router output over all 16 experts. Step 2 — For new input X, compute cross-entropy distance f(I_0, Y_i) between its routing distribution I_0 and each dataset reference Y_i. Step 3 — Classify X to dataset i_0 = argmin_i f(I_0, Y_i).", "source": "Section B.4 (derived from D2 ordering_before/ordering_after annotations)" }, { "id": "moe-pot-D4-003", "claim": "Zero-shot evaluation protocol (Section 5.1): Phase 1 — Data preprocessing (spatial resolution unification to H=128, channel padding, mask channel for irregular geometries, patchification P=8). Phase 2 — Joint pre-training on all 6 datasets (auto-regressive next-frame prediction, T=10, noise injection, balanced sampling w_k=1, Adam lr=1e-3, 1000 epochs, 200 warm-up). Phase 3 — Zero-shot evaluation on each individual dataset test split.", "source": "Section 5.1 (derived from D3 phase_ordering)" }, { "id": "moe-pot-D4-004", "claim": "Fine-tuning evaluation protocol (Section 5.1): Phase 1 — Joint pre-training on all 6 datasets (1000 epochs). Phase 2 — Fine-tune separately on each individual dataset (200 epochs, one-cycle lr=1e-3, 40 warm-up, freeze router-gating, update expert networks only). Phase 3 — Evaluate on same dataset test split.", "source": "Section 5.1, Section B.3 (derived from D3 phase_ordering)" }, { "id": "moe-pot-D4-005", "claim": "Downstream transfer evaluation protocol (Section 5.2): Phase 1 — Joint pre-training on 6 datasets (1000 epochs). Phase 2 — Fine-tune on downstream task (NS(1e-4), CNS(1,0.01), or PDEArena) for 500 epochs (one-cycle lr=1e-3, 100 warm-up). Phase 3 — Evaluate on downstream task test split. Compared against train-from-scratch baseline (no pre-training).", "source": "Section 5.2, Section B.3 (derived from D3 phase_ordering)" }, { "id": "moe-pot-D4-006", "claim": "Scaling law analysis protocol (Section 5.3): Phase 1 — Pre-train each model variant (T/S/M for MoE-POT, T/S/M/L for DPOT) on all 6 datasets. Phase 2 — Evaluate zero-shot L2RE on test splits. Phase 3 — Fine-tune each model variant on individual datasets. Phase 4 — Evaluate fine-tuned L2RE on test splits. Phase 5 — Plot L2RE vs. activated parameters to characterize scaling behavior for dense vs. sparse architectures.", "source": "Section 5.3 (derived from D3 phase_ordering)" }, { "id": "moe-pot-D4-007", "claim": "Negative transfer analysis protocol (Appendix C.5): Phase 1 — Pre-train DPOT-S (dense) and MoE-POT-S (sparse) from scratch on progressively larger dataset mixtures: 6 datasets (base) -> 10 datasets (base + NS(1e-4), CNS(1,0.1), 2x PDEArena) -> 12 datasets (10-set + CNS(1,0.01), CNS(0.1,0.1)). Phase 2 — Zero-shot evaluate both models on the original 6 base dataset test splits to measure whether dense models suffer negative transfer while MoE remains stable.", "source": "Appendix C.5 (derived from D3 phase_ordering)" } ] }