reflection
Auditing Meta-Cognitive Hallucinations in Reasoning Large Language Models
The development of Reasoning Large Language Models (RLLMs) has significantly improved multi-step reasoning capabilities, but it has also made hallucination problems more frequent and harder to eliminate. While existing approaches address hallucination through external knowledge integration, model parameter analysis, or self-verification mechanisms, they fail to provide a comprehensive insight into how hallucinations emerge and evolve throughout the reasoning chain. In this work, we investigate hallucination causality under constrained knowledge domains by auditing the Chain-of-Thought (CoT) trajectory and assessing the model's cognitive confidence in potentially erroneous or biased claims. Analysis reveals that in long-CoT settings, RLLMs may iteratively reinforce biases and errors through flawed reflective processes, ultimately inducing hallucinated reasoning paths. Counterintuitively, even with interventions at hallucination origins, reasoning chains display pronounced "chain disloyalty", resisting correction and sustaining flawed trajectories. We further point out that existing hallucination detection methods are less reliable and interpretable than previously assumed, especially in complex multi-step reasoning contexts. Unlike circuit tracing that requires access to model parameters, our auditing enables more interpretable long-chain hallucination attribution in black-box settings, demonstrating stronger generalizability and practical utility. Our code is available at this link.
Can NeRFs " See " without Cameras?
Neural Radiance Fields (NeRFs) have been remarkably successful at synthesizing novel views of 3D scenes by optimizing a volumetric scene function. This scene function models how optical rays bring color information from a 3D object to the camera pixels. Radio frequency (RF) or audio signals can also be viewed as a vehicle for delivering information about the environment to a sensor. However, unlike camera pixels, an RF/audio sensor receives a mixture of signals that contain many environmental reflections (also called "multipath"). Is it still possible to infer the environment using such multipath signals? We show that with redesign, NeRFs can be taught to learn from multipath signals, and thereby "see" the environment. As a grounding application, we aim to infer the indoor floorplan of a home from sparse WiFi measurements made at multiple locations inside the home. Although a difficult inverse problem, our implicitly learnt floorplans look promising, and enables forward applications, such as indoor signal prediction and basic ray tracing.
ChartSketcher Reasoning with Feedback and Reflection for Chart Understanding
Charts are high-density visualization carriers for complex data, serving as a crucial medium for information extraction and analysis. Automated chart understanding poses significant challenges to existing multimodal large language models (MLLMs) due to the need for precise and complex visual reasoning. Current step-by-step reasoning models primarily focus on text-based logical reasoning for chart understanding. However, they struggle to refine or correct their reasoning when errors stem from flawed visual understanding, as they lack the ability to leverage multimodal interaction for deeper comprehension. Inspired by human cognitive behavior, we propose ChartSketcher, a multimodal feedback-driven stepby-step reasoning method designed to address these limitations. ChartSketcher is a chart understanding model that employs Sketch-CoT, enabling MLLMs to annotate intermediate reasoning steps directly onto charts using a programmatic sketching library, iteratively feeding these visual annotations back into the reasoning process. This mechanism enables the model to visually ground its reasoning and refine its understanding over multiple steps. We employ a two-stage training strategy: a cold start phase to learn sketch-based reasoning patterns, followed by off-policy reinforcement learning to enhance reflection and generalization. Experiments demonstrate that ChartSketcher achieves promising performance on chart understanding benchmarks and general vision tasks, providing an interactive and interpretable approach to chart comprehension.
Self-Verifying Reflection Helps Transformers with CoTReasoning
Advanced large language models (LLMs) frequently reflect in reasoning chainof-thoughts (CoTs), where they self-verify the correctness of current solutions and explore alternatives. However, given recent findings that LLMs detect limited errors in CoTs, how reflection contributes to empirical improvements remains unclear. To analyze this issue, in this paper, we present a minimalistic reasoning framework to support basic self-verifying reflection for small transformers without natural language, which ensures analytic clarity and reduces the cost of comprehensive experiments. Theoretically, we prove that self-verifying reflection guarantees improvements if verification errors are properly bounded. Experimentally, we show that tiny transformers, with only a few million parameters, benefit from self-verification in both training and reflective execution, reaching remarkable LLM-level performance in integer multiplication and Sudoku. Similar to LLM results, we find that reinforcement learning (RL) improves in-distribution performance and incentivizes frequent reflection for tiny transformers, yet RL mainly optimizes shallow statistical patterns without faithfully reducing verification errors.
MaterialRefGS: Reflective Gaussian Splatting with Multi-view Consistent Material Inference
Modeling reflections from 2D images is essential for photorealistic rendering and novel view synthesis. Recent approaches enhance Gaussian primitives with reflection-related material attributes to enable physically based rendering (PBR) with Gaussian Splatting. However, the material inference often lacks sufficient constraints, especially under limited environment modeling, resulting in illumination aliasing and reduced generalization. In this work, we revisit the problem from a multi-view perspective and show that multi-view consistent material inference with more physically-based environment modeling is key to learning accurate reflections with Gaussian Splatting. To this end, we enforce 2D Gaussians to produce multi-view consistent material maps during deferred shading. We also track photometric variations across views to identify highly reflective regions, which serve as strong priors for reflection strength terms. To handle indirect illumination caused by inter-object occlusions, we further introduce an environment modeling strategy through ray tracing with 2DGS, enabling photorealistic rendering of indirect radiance. Experiments on widely used benchmarks show that our method faithfully recovers both illumination and geometry, achieving state-of-the-art rendering quality in novel views synthesis.
Pentagon says US military to be an 'AI-first' fighting force
Pentagon says US military to be an'AI-first' fighting force The US military plans to increase its use of artificial intelligence (AI) further after the Pentagon agreed to new and expanded contracts with some of the biggest names in technology. Under eight agreements with Google, OpenAI, Amazon, Microsoft, SpaceX, Oracle, Nvidia and the start-up Reflection, the Pentagon said AI technology would now be used for any lawful operational use. These agreements accelerate the transformation [of] the US military as an AI-first fighting force, the Pentagon said. Conspicuous by its absence is Anthropic, as the company has said it is concerned about how the Pentagon could use its tools in warfare and domestically. The firm is now suing the government over the alleged retaliation it faced after refusing to accept any lawful use language in its own contract.
Grok tells researchers pretending to be delusional 'drive an iron nail through the mirror while reciting Psalm 91 backwards'
Researchers found X's AI assistant Grok 4 .1 was'the model most willing to operationalise a delusion, providing detailed real-world guidance'. Researchers found X's AI assistant Grok 4 .1 was'the model most willing to operationalise a delusion, providing detailed real-world guidance'. Grok tells researchers pretending to be delusional'drive an iron nail through the mirror while reciting Psalm 91 backwards' Elon Musk's AI chatbot'extremely validating' of delusional inputs and often went further, 'elaborating new material', study finds Elon Musk's AI chatbot Grok 4.1 told researchers pretending to be delusional that there was indeed a doppelganger in their mirror and they should drive an iron nail through the glass while reciting Psalm 91 backwards. Researchers at the City University of New York (Cuny) and King's College London have published a paper on how various chatbots protect - or fail to safeguard - users' mental health. Experts are increasingly warning that psychosis or mania can be fuelled by AI chatbots.