ICLR 2025 Papers

Reversible architectures have been shown to be capable of performing on par with their non-reversible architectures, being applied in deep learning for memory savings and generative modeling. In this work, we show how reversible architectures can solve challenges in parallelizing deep model training. We introduce PETRA, a novel alternative to backpropagation for parallelizing gradient computations. PETRA facilitates effective model parallelism by enabling stages (i.e., a set of layers) to compute independently on different devices, while only needing to communicate activations and gradients between each other. By decoupling the forward and backward passes and keeping a single updated version of the parameters, the need for weight stashing is also removed. We develop a custom autograd-like training framework for PETRA, and we demonstrate its effectiveness on standard computer vision benchmarks, achieving competitive accuracies comparable to backpropagation using ResNet-18, ResNet-34, and ResNet-50 models.

Convolutional Neural Networks (CNNs) have profoundly influenced the field of computer vision, drawing significant inspiration from the visual processing mechanisms inherent in the brain. Despite sharing fundamental structural and representational similarities with the biological visual system, differences in local connectivity patterns within CNNs open up an interesting area to explore. In this work, we explore whether integrating biologically observed receptive fields (RFs) can enhance model performance and foster alignment with brain representations. We introduce a novel methodology, termed $L_p$-convolution, which employs the multivariate $L_p$-generalized normal distribution as an adaptable $L_p$-masks, to reconcile disparities between artificial and biological RFs. $L_p$-masks finds the optimal RFs through task-dependent adaptation of conformation such as distortion, scale, and rotation. This allows $L_p$-convolution to excel in tasks that require flexible RF shapes, including not only square-shaped regular RFs but also horizontal and vertical ones. Furthermore, we demonstrate that $L_p$-convolution with biological RFs significantly enhances the performance of large kernel CNNs possibly by introducing structured sparsity inspired by $L_p$-generalized normal distribution in convolution. Lastly, we present that neural representations of CNNs align more closely with the visual cortex when -convolution is close to biological RFs.

We reframe scene flow as the task of estimating a continuous space-time ordinary differential equation (ODE) that describes motion for an entire observation sequence, represented with a neural prior. Our method, EulerFlow, optimizes this neural prior estimate against several multi-observation reconstruction objectives, enabling high quality scene flow estimation via self-supervision on real-world data. EulerFlow works out-of-the-box without tuning across multiple domains, including large-scale autonomous driving scenes and dynamic tabletop settings. Remarkably, EulerFlow produces high quality flow estimates on small, fast moving objects like birds and tennis balls, and exhibits emergent 3D point tracking behavior by solving its estimated ODE over long-time horizons. On the Argoverse 2 2024 Scene Flow Challenge, EulerFlow outperforms all prior art, surpassing the next-best unsupervised method by more than 2.5 times, and even exceeding the next-best supervised method by over 10%. See https://vedder.io/eulerflow for interactive visuals.