Sparse Universal Transformer
On the map: Mixture-of-experts → Expert routing strategies
Abstract (arXiv)
The Universal Transformer (UT) is a variant of the Transformer that shares parameters across its layers. Empirical evidence shows that UTs have better compositional generalization than Vanilla Transformers (VTs) in formal language tasks. The parameter-sharing also affords it better parameter efficiency than VTs. Despite its many advantages, scaling UT parameters is much more compute and memory intensive than scaling up a VT. This paper proposes the Sparse Universal Transformer (SUT), which leverages Sparse Mixture of Experts (SMoE) and a new stick-breaking-based dynamic halting mechanism to reduce UT's computation complexity while retaining its parameter efficiency and generalization ability. Experiments show that SUT achieves the same performance as strong baseline models while only using half computation and parameters on WMT'14 and strong generalization results on formal language tasks (Logical inference and CFQ). The new halting mechanism also enables around 50% reduction in computation during inference with very little performance decrease on formal language tasks.
Key facts. Cited by 28 papers in the map (data through 7 Oct 2026). Placed in Expert routing strategies, one of 12 directions in Mixture-of-experts. Builds on 41 of its 47 references that are in the map. First posted on arXiv 11 Oct 2023.
Builds on
41 of 47 references.
Closest ancestors · 2
Same direction, newest first
- 2022Mixture of Attention Heads: Selecting Attention Heads Per Token11 Oct
- 2021Switch Transformers: Scaling to Trillion Parameter Models with Simple and Efficient Sparsity11 Jan
Other references · 39
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- 2019ALBERT: A Lite BERT for Self-supervised Learning of Language Representationscited by 2,772
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- 2020Long Range Arena: A Benchmark for Efficient Transformerscited by 696
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- 2019Theoretical Limitations of Self-Attention in Neural Sequence Modelscited by 286
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- 2021The Devil is in the Detail: Simple Tricks Improve Systematic Generalization of Transformerscited by 117
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- 2022Compositional Semantic Parsing with Large Language Modelscited by 95
- 2022Formal Language Recognition by Hard Attention Transformers: Perspectives from Circuit Complexitycited by 92
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- 2019Compositional generalization in a deep seq2seq model by separating syntax and semanticscited by 56
- 2020Very Deep Transformers for Neural Machine Translationcited by 50
- 2019Compositional Generalization for Primitive Substitutionscited by 48
- 2018The Importance of Being Recurrent for Modeling Hierarchical Structurecited by 42
- 2021Systematic Generalization with Edge Transformerscited by 38
- 2021Sequence-to-Sequence Learning with Latent Neural Grammarscited by 30
- 2021Disentangled Sequence to Sequence Learning for Compositional Generalizationcited by 30
- 2015Tree-structured composition in neural networks without tree-structured architecturescited by 23
- 2020A Mixture of h-1 Heads is Better than h Headscited by 22
- 2019Ordered Memorycited by 20
- 2022Mod-Squad: Designing Mixture of Experts As Modular Multi-Task Learnerscited by 15
- 2020Recursive Top-Down Production for Sentence Generation with Latent Treescited by 2
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Citing papers per year: 2023: 1; 2024: 8; 2025: 11; 2026: 8.
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- 2026SpiralFormer: Looped Transformers Can Learn Hierarchical Dependencies via Multi-Resolution Recursion12 Feb 2026
- 2026Depth-Recurrent Attention Mixtures: Giving Latent Reasoning the Attention it Deserves29 Jan 2026
- 2025Block-Recurrent Dynamics in Vision Transformers23 Dec 2025
- 2025MeSH: Memory-as-State-Highways for Recursive Transformers9 Oct 2025
- 2025Encode, Think, Decode: Scaling test-time reasoning with recursive latent thoughts8 Oct 2025
- 2025Mixture-of-Recursions: Learning Dynamic Recursive Depths for Adaptive Token-Level Computation14 Jul 2025
16 more
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- 2025SCOUT: Teaching Pre-trained Language Models to Enhance Reasoning via Flow Chain-of-Thought30 May 2025
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- 2025Hyper-SET: Designing Transformers via Hyperspherical Energy Minimization17 Feb 2025
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- 2024A Survey on Inference Optimization Techniques for Mixture of Experts Models18 Dec 2024
- 2024Scaling Stick-Breaking Attention: An Efficient Implementation and In-depth Study23 Oct 2024
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- 2024MoEUT: Mixture-of-Experts Universal Transformers25 May 2024
- 2024Grokked Transformers are Implicit Reasoners: A Mechanistic Journey to the Edge of Generalization23 May 2024
- 2024Scattered Mixture-of-Experts Implementation13 Mar 2024
- 2024Conditional computation in neural networks: principles and research trends12 Mar 2024
- 2024Investigating Recurrent Transformers with Dynamic Halt1 Feb 2024
- 2023Adaptive Computation Modules: Granular Conditional Computation For Efficient Inference15 Dec 2023
- 2025Scaling up Test-Time Compute with Latent Reasoning: A Recurrent Depth Approachcited by 372
- 2024Grokked Transformers are Implicit Reasoners: A Mechanistic Journey to the Edge of Generalizationcited by 78
- 2026A Mechanistic Analysis of Looped Reasoning Language Modelscited by 27
- 2025Encode, Think, Decode: Scaling test-time reasoning with recursive latent thoughtscited by 23
- 2025SCOUT: Teaching Pre-trained Language Models to Enhance Reasoning via Flow Chain-of-Thoughtcited by 7
- 2025Zero Token-Driven Deep Thinking in LLMs: Unlocking the Full Potential of Existing Parameters via Cyclic Refinementcited by 5
- 2026A Mechanistic Analysis of Looped Reasoning Language Models13 Apr 2026
- 2025Encode, Think, Decode: Scaling test-time reasoning with recursive latent thoughts8 Oct 2025
- 2025SCOUT: Teaching Pre-trained Language Models to Enhance Reasoning via Flow Chain-of-Thought30 May 2025
- 2025Zero Token-Driven Deep Thinking in LLMs: Unlocking the Full Potential of Existing Parameters via Cyclic Refinement17 Feb 2025
- 2025Scaling up Test-Time Compute with Latent Reasoning: A Recurrent Depth Approach7 Feb 2025
- 2024Grokked Transformers are Implicit Reasoners: A Mechanistic Journey to the Edge of Generalization23 May 2024
- 2024OLMoE: Open Mixture-of-Experts Language Modelscited by 291
- 2024MoEUT: Mixture-of-Experts Universal Transformerscited by 55
- 2024A Survey on Inference Optimization Techniques for Mixture of Experts Modelscited by 46
- 2024Scattered Mixture-of-Experts Implementationcited by 15
- 2024Conditional computation in neural networks: principles and research trendscited by 10
- 2025Chain-of-Experts: Unlocking the Communication Power of Mixture-of-Experts Modelscited by 7
- 2025Chain-of-Experts: Unlocking the Communication Power of Mixture-of-Experts Models23 Jun 2025
- 2024A Survey on Inference Optimization Techniques for Mixture of Experts Models18 Dec 2024
- 2024OLMoE: Open Mixture-of-Experts Language Models3 Sep 2024
- 2024MoEUT: Mixture-of-Experts Universal Transformers25 May 2024
- 2024Scattered Mixture-of-Experts Implementation13 Mar 2024
- 2024Conditional computation in neural networks: principles and research trends12 Mar 2024
- 2025Mixture-of-Recursions: Learning Dynamic Recursive Depths for Adaptive Token-Level Computationcited by 120
- 2025Continuous Thought Machinescited by 21
- 2025Block-Recurrent Dynamics in Vision Transformerscited by 16
- 2024Scaling Stick-Breaking Attention: An Efficient Implementation and In-depth Studycited by 13
- 2026Depth-Recurrent Attention Mixtures: Giving Latent Reasoning the Attention it Deservescited by 11
- 2026Hyperloop Transformerscited by 11
- 2026SpiralFormer: Looped Transformers Can Learn Hierarchical Dependencies via Multi-Resolution Recursioncited by 9
- 2025MeSH: Memory-as-State-Highways for Recursive Transformerscited by 8
- 2023Adaptive Computation Modules: Granular Conditional Computation For Efficient Inferencecited by 6
- 2024Investigating Recurrent Transformers with Dynamic Haltcited by 5
- 2026LT2: Linear-Time Looped Transformerscited by 5
- 2026Depth-adaptive Inference of Looped Language Models via Continuous Depth Batchingcited by 4
12 most cited of 13 All 13 (JSON)
- 2026Depth-adaptive Inference of Looped Language Models via Continuous Depth Batching10 Aug 2026
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- 2026Hyperloop Transformers23 Apr 2026
- 2026SpiralFormer: Looped Transformers Can Learn Hierarchical Dependencies via Multi-Resolution Recursion12 Feb 2026
- 2026Depth-Recurrent Attention Mixtures: Giving Latent Reasoning the Attention it Deserves29 Jan 2026
- 2025Block-Recurrent Dynamics in Vision Transformers23 Dec 2025
- 2025MeSH: Memory-as-State-Highways for Recursive Transformers9 Oct 2025
- 2025Mixture-of-Recursions: Learning Dynamic Recursive Depths for Adaptive Token-Level Computation14 Jul 2025
- 2025Continuous Thought Machines8 May 2025
- 2025Hyper-SET: Designing Transformers via Hyperspherical Energy Minimization17 Feb 2025
- 2024Scaling Stick-Breaking Attention: An Efficient Implementation and In-depth Study23 Oct 2024
- 2024Investigating Recurrent Transformers with Dynamic Halt1 Feb 2024
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