LDLMIn construction

Size
306M trained
Published
Meshchaninov et al. · May 2026
Line
Diffusion language model
View
Architecture
Source

LDLM @ e18c42a, not yet public · arXiv:2605.07933v1 · OpenWebText · 1024 · checkpoint, tokenizer and saved statistics not verifiedHow to read

Token decoder

Token decoder

Reconstructed features

×

tensor

The latent decoder’s output.

shape
h^\hat h [B batch, T positions, 768 d]
Sources

Contextual evidence from Latent decoder

The latent decoder owns one position table, the mask token’s vector copied from the token table of a GPT-2 loaded for the purpose and frozen because the feature model is configured frozen, an MLP for the queries, the blocks and a scale for the prepared queries.

The implementation, pinned at revision e18c42acdfb7, not yet public

Contextual evidence from Latent decoder

Every query is the mask vector: it passes the MLP and a scale, positions are added; the latents take the same position table; the blocks are applied; every position counts as masked.

The implementation, pinned at revision e18c42acdfb7, not yet public

Contextual evidence from Latent decoder

The latent decoder: 12 heads of 64 features, query and key normalization, softcap 50, 6 layers, MLP multiplier 4; the token decoder has 3 blocks.

The implementation, pinned at revision e18c42acdfb7, not yet public

Contextual evidence from Latent decoder

The feature model is GPT-2, frozen; the hidden state at index −3 is extracted; the encoder and the decoder are of the Perceiver kind; the file’s vocabulary size and mask token ID are defaults that the trainer overwrites with the tokenizer’s; there are as many latents as positions, of 768 features.

The implementation, pinned at revision e18c42acdfb7, not yet public

Contextual evidence from Token-decoder block

The token decoder: a rotary table, the configured number of blocks, and a linear readout to the vocabulary without bias.

The implementation, pinned at revision e18c42acdfb7, not yet public

Contextual evidence from Token-decoder block

The token decoder’s blocks: no softcap, no time conditioning, the gated MLP with the configured multiplier.

The implementation, pinned at revision e18c42acdfb7, not yet public

Contextual evidence from Token-decoder block

A block owns two gain-only LayerNorms, a fused query–key–value projection and an output projection without bias, an MLP of the configured kind, and, with modulation, an affine layer from the time condition to six vectors, initialized at zero.

The implementation, pinned at revision e18c42acdfb7, not yet public

Contextual evidence from Token-decoder block

A block normalizes, modulates by the time condition’s shift and scale, projects to queries, keys and values, rotates queries and keys, attends over all positions with softcap, and adds the projected output scaled by a gate; the MLP branch does the same with its own shift, scale and gate.

The implementation, pinned at revision e18c42acdfb7, not yet public