All articles
media Latent Space · 14d ago

Midjourney Launches Full-Body Ultrasound CT Scanner

Midjourney has announced a full-body ultrasound CT scanner, calling it the first new whole-body medical imaging modality in 50 years. The prototype, known as the Midjourney Scanner, uses 8,960 transducers across 40 systems in a 70 cm ring to capture data at 17 GB/s, with claimed resolution down to 0.5 mm and a goal of 358,000 ultrasonic elements. The system is currently in Gen 1, with scans taking 20 minutes and no AI used in image generation yet, though future versions aim to integrate AI and reach 50,000 scanners by enabling 1 billion scans monthly.

arxiv arXiv cs.LG · 14d ago

Discriminator-Guided RL Corrects Flow Matching with Data-Aligned Rewards

Discriminator-Guided RL (DRL) uses a pretrained representation space to train a discriminator that separates real data from model-generated samples. Its logit is used as a reward in KL-regularized RL, aligning model outputs with visual and semantic realism without human preferences. DRL improves FID and semantic FD across models like SiT and JiT, and enhances the Pareto frontier between preference and fidelity.

arxiv arXiv cs.LG · 14d ago

Generalised Eigenvalue Geometry of Semantic Adversarial Attacks

A new theory models how semantic paraphrases can fool financial sentiment classifiers by analyzing the worst-case displacement of target model representations. The attackability index λ*(x) is derived from the largest generalised eigenvalue of a matrix pencil (A,B), offering closed-form predictions and robustness certificates for affine readouts. The framework connects continuous perturbation theory to discrete paraphrase search, with empirical validation on real financial text classifiers.