ComplexFormer: Disruptively Advancing Transformer Inference Ability via Head-Specific Complex Vector Attention

Fuente: arXiv
Guardado en:
Detalles Bibliográficos
Autores principales: Shao, Jintian, Huang, Hongyi, Wu, Jiayi, Zhang, Beiwen, Wu, ZhiYu, Shan, You, Zheng, MingKai
Formato: Preprint
Publicado: 2025
Materias:
Acceso en línea:
Etiquetas: Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
_version_ 1866908381142319104
author Shao, Jintian
Huang, Hongyi
Wu, Jiayi
Zhang, Beiwen
Wu, ZhiYu
Shan, You
Zheng, MingKai
author_facet Shao, Jintian
Huang, Hongyi
Wu, Jiayi
Zhang, Beiwen
Wu, ZhiYu
Shan, You
Zheng, MingKai
contents Transformer models rely on self-attention to capture token dependencies but face challenges in effectively integrating positional information while allowing multi-head attention (MHA) flexibility. Prior methods often model semantic and positional differences disparately or apply uniform positional adjustments across heads, potentially limiting representational capacity. This paper introduces ComplexFormer, featuring Complex Multi-Head Attention-CMHA. CMHA empowers each head to independently model semantic and positional differences unified within the complex plane, representing interactions as rotations and scaling. ComplexFormer incorporates two key improvements: (1) a per-head Euler transformation, converting real-valued query/key projections into polar-form complex vectors for head-specific complex subspace operation; and (2) a per-head adaptive differential rotation mechanism, exp[i(Adapt(ASmn,i) + Delta(Pmn),i)], allowing each head to learn distinct strategies for integrating semantic angle differences (ASmn,i) with relative positional encodings (Delta(Pmn),i). Extensive experiments on language modeling, text generation, code generation, and mathematical reasoning show ComplexFormer achieves superior performance, significantly lower generation perplexity , and improved long-context coherence compared to strong baselines like RoPE-Transformers. ComplexFormer demonstrates strong parameter efficiency, offering a more expressive, adaptable attention mechanism.
format Preprint
id arxiv_https___arxiv_org_abs_2505_10222
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle ComplexFormer: Disruptively Advancing Transformer Inference Ability via Head-Specific Complex Vector Attention
Shao, Jintian
Huang, Hongyi
Wu, Jiayi
Zhang, Beiwen
Wu, ZhiYu
Shan, You
Zheng, MingKai
Machine Learning
Computation and Language
Transformer models rely on self-attention to capture token dependencies but face challenges in effectively integrating positional information while allowing multi-head attention (MHA) flexibility. Prior methods often model semantic and positional differences disparately or apply uniform positional adjustments across heads, potentially limiting representational capacity. This paper introduces ComplexFormer, featuring Complex Multi-Head Attention-CMHA. CMHA empowers each head to independently model semantic and positional differences unified within the complex plane, representing interactions as rotations and scaling. ComplexFormer incorporates two key improvements: (1) a per-head Euler transformation, converting real-valued query/key projections into polar-form complex vectors for head-specific complex subspace operation; and (2) a per-head adaptive differential rotation mechanism, exp[i(Adapt(ASmn,i) + Delta(Pmn),i)], allowing each head to learn distinct strategies for integrating semantic angle differences (ASmn,i) with relative positional encodings (Delta(Pmn),i). Extensive experiments on language modeling, text generation, code generation, and mathematical reasoning show ComplexFormer achieves superior performance, significantly lower generation perplexity , and improved long-context coherence compared to strong baselines like RoPE-Transformers. ComplexFormer demonstrates strong parameter efficiency, offering a more expressive, adaptable attention mechanism.
title ComplexFormer: Disruptively Advancing Transformer Inference Ability via Head-Specific Complex Vector Attention
topic Machine Learning
Computation and Language
url https://arxiv.org/abs/2505.10222