Deep Learning
Scaling Language-Centric Omnimodal Representation Learning
Xiao, Chenghao, Chan, Hou Pong, Zhang, Hao, Xu, Weiwen, Aljunied, Mahani, Rong, Yu
Recent multimodal embedding approaches leveraging multimodal large language models (MLLMs) fine-tuned with contrastive learning (CL) have shown promising results, yet the underlying reasons behind their superiority remain underexplored. This work argues that a crucial advantage of MLLM-based approaches stems from implicit cross-modal alignment achieved during generative pretraining, where the language decoder learns to exploit multimodal signals within a shared representation space for generating unimodal outputs. Through analysis of anisotropy and kernel similarity structure, we empirically confirm that latent alignment emerges within MLLM representations, allowing CL to serve as a lightweight refinement stage. Leveraging this insight, we propose a Language-Centric Omnimodal Embedding framework, termed LCO-Emb. Extensive experiments across diverse backbones and benchmarks demonstrate its effectiveness, achieving state-of-the-art performance across modalities. Furthermore, we identify a Generation-Representation Scaling Law (GRSL), showing that the representational capabilities gained through contrastive refinement scales positively with the MLLM's generative capabilities. This suggests that improving generative abilities evolves as an effective paradigm for enhancing representation quality. We provide a theoretical explanation of GRSL, which formally links the MLLM's generative quality to the upper bound on its representation performance, and validate it on a challenging, low-resource visual-document retrieval task, showing that continual generative pretraining before CL can further enhance the potential of a model's embedding capabilities. Codes, models, and resources are available at https://github.com/LCO-Embedding/LCO-Embedding.
Diffusion Transformers with Representation Autoencoders
Zheng, Boyang, Ma, Nanye, Tong, Shengbang, Xie, Saining
Latent generative modeling, where a pretrained autoencoder maps pixels into a latent space for the diffusion process, has become the standard strategy for Diffusion Transformers (DiT); however, the autoencoder component has barely evolved. Most DiTs continue to rely on the original V AE encoder, which introduces several limitations: outdated backbones that compromise architectural simplicity, low-dimensional latent spaces that restrict information capacity, and weak representations that result from purely reconstruction-based training and ultimately limit generative quality. In this work, we explore replacing the V AE with pretrained representation encoders (e.g., DINO, SigLIP, MAE) paired with trained decoders, forming what we term Representation Autoencoders (RAEs). These models provide both high-quality reconstructions and semantically rich latent spaces, while allowing for a scalable transformer-based architecture. Since these latent spaces are typically high-dimensional, a key challenge is enabling diffusion transformers to operate effectively within them. We analyze the sources of this difficulty, propose theoretically motivated solutions, and validate them empirically. Our approach achieves faster convergence without auxiliary representation alignment losses. Using a DiT variant equipped with a lightweight, wide DDT head, we achieve strong image generation results on ImageNet: 1.51 FID at 256 256 (no guidance) and 1.13 at both 256 256 and 512 512 (with guidance). RAE offers clear advantages and should be the new default for diffusion transformer training. Project page: rae-dit.github.io Figure 1: Representation Autoencoder (RAE) uses frozen pretrained representations as the encoder with a lightweight decoder to reconstruct input images without compression. RAE enables faster convergence and higher-quality samples in latent diffusion training compared to V AE-based models. The evolution of generative modeling has been driven by a continual redefinition of where and how models learn to represent data. Early pixel-space models sought to directly capture image statistics, but the emergence of latent diffusion (V ahdat et al., 2021; Rombach et al., 2022) reframed generation as a process operating within a learned, compact representation space. By diffusing in this space rather than in raw pixels, models such as Latent Diffusion Models (LDM) (Rombach et al., 2022) and Diffusion Transformers (DiT) (Peebles & Xie, 2023; Ma et al., 2024) achieve higher visual fidelity and efficiency, powering the most capable image and video generators of today. Despite progress in diffusion backbones, the autoencoder defining the latent space remains largely unchanged. The widely used SD-V AE (Rombach et al., 2022) still relies on heavy channel-wise 1 In addition, SD-V AE, built on a legacy convolutional design, remains computationally inefficient (see Figure 1).
PACEbench: A Framework for Evaluating Practical AI Cyber-Exploitation Capabilities
Liu, Zicheng, Huang, Lige, Zhang, Jie, Liu, Dongrui, Tian, Yuan, Shao, Jing
For instance, while several models can exploit CVE-2023-50564 in the isolated A-CVE setting, none succeed in the corresponding B-CVE environment where the vulnerable target is blended with benign hosts (BN 4 challenge). The C-CVE scenarios, which simulate more realistic penetration tests with multi-host dependencies, present an even greater challenge. As shown in Table 1, model performance drops further in these scenarios, with agents often completing only intermediate steps rather than the full end-to-end attack. For example, in the Chain 1 challenge, agents manage to compromise the initial perimeter server but fail in the subsequent phases of lateral movement, privilege escalation, or internal target discovery, thus failing to complete the full attack chain. Current model could not bypass the deployed cyber defenses. As shown in Table 1, every model score zero in the D-CVE scenarios, suggesting that no agent could autonomously discover a bypass for any of the up-to-date W AFs. This finding is particularly significant, as it indicates that current model capabilities have not yet crossed a key "safety red line" (red-lines.ai,
FACE: Faithful Automatic Concept Extraction
Bhusal, Dipkamal, Clifford, Michael, Rampazzi, Sara, Rastogi, Nidhi
Interpreting deep neural networks through concept-based explanations offers a bridge between low-level features and high-level human-understandable semantics. However, existing automatic concept discovery methods often fail to align these extracted concepts with the model's true decision-making process, thereby compromising explanation faithfulness. In this work, we propose FACE (Faithful Automatic Concept Extraction), a novel framework that augments Non-negative Matrix Factorization (NMF) with a Kullback-Leibler (KL) divergence regularization term to ensure alignment between the model's original and concept-based predictions. Unlike prior methods that operate solely on encoder activations, FACE incorporates classifier supervision during concept learning, enforcing predictive consistency and enabling faithful explanations. We provide theoretical guarantees showing that minimizing the KL divergence bounds the deviation in predictive distributions, thereby promoting faithful local linearity in the learned concept space. Systematic evaluations on ImageNet, COCO, and CelebA datasets demonstrate that FACE outperforms existing methods across faithfulness and sparsity metrics.
SR-Scientist: Scientific Equation Discovery With Agentic AI
Xia, Shijie, Sun, Yuhan, Liu, Pengfei
Recently, Large Language Models (LLMs) have been applied to scientific equation discovery, leveraging their embedded scientific knowledge for hypothesis generation. However, current methods typically confine LLMs to the role of an equation proposer within search algorithms like genetic programming. In this paper, we present SR-Scientist, a framework that elevates the LLM from a simple equation proposer to an autonomous AI scientist that writes code to analyze data, implements the equation as code, submits it for evaluation, and optimizes the equation based on experimental feedback. Specifically, we wrap the code interpreter into a set of tools for data analysis and equation evaluation. The agent is instructed to optimize the equation by utilizing these tools over a long horizon with minimal human-defined pipelines. Empirical results show that SR-Scientist outperforms baseline methods by an absolute margin of 6% to 35% on datasets covering four science disciplines. Additionally, we demonstrate our method's robustness to noise, the generalization of the discovered equations to out-of-domain data, and their symbolic accuracy. Furthermore, we develop an end-to-end reinforcement learning framework to enhance the agent's capabilities.
EvoCAD: Evolutionary CAD Code Generation with Vision Language Models
Preintner, Tobias, Yuan, Weixuan, Kรถnig, Adrian, Bรคck, Thomas, Raponi, Elena, van Stein, Niki
Abstract--Combining large language models with evolutionary computation algorithms represents a promising research direction leveraging the remarkable generative and in-context learning capabilities of LLMs with the strengths of evolutionary algorithms. Our method samples multiple CAD objects, which are then optimized using an evolutionary approach with vision language and reasoning language models. We assess our method using GPT -4V and GPT -4o, evaluating it on the CAD-Prompt benchmark dataset and comparing it to prior methods. Additionally, we introduce two new metrics based on topological properties defined by the Euler characteristic, which capture a form of semantic similarity between 3D objects. Our results demonstrate that EvoCAD outperforms previous approaches on multiple metrics, particularly in generating topologically correct objects, which can be efficiently evaluated using our two novel metrics that complement existing spatial metrics. The use of generative AI tools powered by large language models (LLMs) has transformed the way humans work, create, and develop. However, while significant attention is directed towards textual knowledge tasks, comparatively little focus is devoted on working with symbolic representations, such as those utilized in computer-aided design (CAD). These code-like textual representations, in the following referred as CAD code, enable visual assets to be processed by LLMs [21].
StoryBox: Collaborative Multi-Agent Simulation for Hybrid Bottom-Up Long-Form Story Generation Using Large Language Models
Chen, Zehao, Pan, Rong, Li, Haoran
Human writers often begin their stories with an overarching mental scene, where they envision the interactions between characters and their environment. Inspired by this creative process, we propose a novel approach to long-form story generation, termed hybrid bottom-up long-form story generation, using multi-agent simulations. In our method, agents interact within a dynamic sandbox environment, where their behaviors and interactions with one another and the environment generate emergent events. These events form the foundation for the story, enabling organic character development and plot progression. Unlike traditional top-down approaches that impose rigid structures, our hybrid bottom-up approach allows for the natural unfolding of events, fostering more spontaneous and engaging storytelling. The system is capable of generating stories exceeding 10,000 words while maintaining coherence and consistency, addressing some of the key challenges faced by current story generation models. We achieve state-of-the-art performance across several metrics. This approach offers a scalable and innovative solution for creating dynamic, immersive long-form stories that evolve organically from agent-driven interactions.
LLM-Oriented Token-Adaptive Knowledge Distillation
Xie, Xurong, Xue, Zhucun, Wu, Jiafu, Li, Jian, Wang, Yabiao, Hu, Xiaobin, Liu, Yong, Zhang, Jiangning
Knowledge distillation (KD) is a key technique for compressing large-scale language models (LLMs), yet prevailing logit-based methods typically employ static strategies that are misaligned with the dynamic learning process of student models. These methods typically treat all tokens indiscriminately and apply a single, fixed temperature, resulting in suboptimal knowledge transfer. To address these limitations, we propose LLM-Oriented Token-Adaptive Knowledge Distillation (AdaKD), a novel framework that adapts the distillation process to the real-time learning state of each token. AdaKD consists of two synergistic modules driven by a unified token difficulty metric. First, our Loss-Driven Adaptive Token Focusing (LATF) module dynamically adjusts the distillation focus by monitoring the student's learning stability, concentrating computational resources on the most valuable tokens at each training phase. Second, we introduce Inverse Difficulty Temperature Scaling (IDTS), a counterintuitive yet effective token-level temperature strategy. It employs low temperatures for difficult tokens for targeted error correction, and high temperatures for easy tokens to encourage students to learn from the teacher's complete and smooth output distribution, thereby enhancing generalization. As a plug-and-play framework, AdaKD can consistently improve the performance of various distillation methods on multiple model architectures and benchmarks.
ParaCook: On Time-Efficient Planning for Multi-Agent Systems
Zhang, Shiqi, Ma, Xinbei, Xu, Yunqing, Cao, Zouying, Lu, Pengrui, Yuan, Haobo, Shen, Tiancheng, Zhang, Zhuosheng, Zhao, Hai, Yang, Ming-Hsuan
Large Language Models (LLMs) exhibit strong reasoning abilities for planning long-horizon, real-world tasks, yet existing agent benchmarks focus on task completion while neglecting time efficiency in parallel and asynchronous operations. To address this, we present ParaCook, a benchmark for time-efficient collaborative planning. Inspired by the Overcooked game, ParaCook provides an environment for various challenging interaction planning of multi-agent systems that are instantiated as cooking tasks, with a simplified action space to isolate the core challenge of strategic parallel planning. Through a comprehensive evaluation of state-of-the-art LLMs, we find that current approaches achieve suboptimal plans, which struggle with parallel actions or coordination. Our analysis also reveals LLMs' potential on abstract tasks where they can focus on high-level parallel optimization. ParaCook provides a scalable evaluation framework with adjustable complexity, establishing a foundation for developing and assessing time efficiency-aware multi-agent planning. The code and data are available at https://github.com/zsq259/ParaCook.
Deconstructing Attention: Investigating Design Principles for Effective Language Modeling
Xue, Huiyin, Moosavi, Nafise Sadat, Aletras, Nikolaos
The success of Transformer language models is widely credited to their dot-product attention mechanism, which interweaves a set of key design principles: mixing information across positions (enabling multi-token interactions), sequence-dependent activations (where attention weights adapt to each input), a specific mathematical form (dot-product similarities plus softmax weighting), and coupling of queries and keys to evolving hidden states (grounding attention in the current layer). However, the necessity of each of these principles remains largely untested. In this work, we systematically deconstruct attention by designing controlled variants that selectively relax these principles, applied both uniformly across all layers and in hybrid architectures where only some layers retain standard attention. Our empirical analysis reveals that mechanisms for mixing tokens are indispensable, as their absence collapses models to near-random behavior, while the exact mathematical form and sequence dependency can be substantially relaxed, especially when preserved in just a subset of layers. Surprisingly, even variants that fail in isolation can achieve robust performance when interleaved with standard attention, highlighting a cooperative effect. These findings deepen our understanding of what truly underpins attention's effectiveness and open new avenues for simplifying language models without sacrificing performance.