CyFM: Cylindrical Optimal Transport for Few-Step Complex-Valued Flow Matching
- URL: http://arxiv.org/abs/2609.14171v1
- Date: Sat, 12 Sep 2026 22:12:33 GMT
- Title: CyFM: Cylindrical Optimal Transport for Few-Step Complex-Valued Flow Matching
- Abstract summary: Complex-valued signals, such as Magnetic Resonance Imaging (MRI) and audio spectrograms, are almost always modelled as flat two-channel Euclidean data.<n>We replace the inherited metric $dA2 + A2 d2$ by the decoupled product metric $dA2 + d2$ and measure what that substitution costs and what it buys.<n>We analyze Cylindrical Flow Matching (CyFM), which strictly bounds the regression target, and couple noise and data by exact minibatch Optimal Transport computed jointly over whole fields in the cylindrical metric.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Complex-valued signals, such as Magnetic Resonance Imaging (MRI) and audio spectrograms, are almost always modelled as flat two-channel Euclidean data. For nonzero values the amplitude-phase chart $z \mapsto (|z|, z/|z|)$ identifies the signal domain with the cylinder $(0, \infty) \times S^1$, on which we deliberately replace the inherited metric $dA^2 + A^2 dθ^2$ by the decoupled product metric $dA^2 + dθ^2$. In this empirical study we measure what that substitution costs and what it buys. By computing exact analytical bridges, we demonstrate that Cartesian paths induce a heavy-tailed distribution of angular velocity (power law index $\approx 1.0$), with nearly half of the probability paths exceeding an angular speed of $π$ under independent coupling, a rate no cylindrical path ever exceeds. To resolve this, we analyze Cylindrical Flow Matching (CyFM), which strictly bounds the regression target, and couple noise and data by exact minibatch Optimal Transport computed jointly over whole fields in the cylindrical metric. Although the transport-cost reduction of this coupling collapses with field dimension (from 86% for scalar pairs to 3% for $64\times64$ fields), its benefit to few-step generation does not: it lowers the few-step error of the cylindrical model by 3-60% at every evaluated resolution. With this coupling, CyFM has a lower error than the best Cartesian baseline at every step count up to $k = 8$ and every evaluated resolution, with all five seeds separated and without distillation, and at convergence we detect no significant difference between the two geometries. Finally, we expose the "Factorized Coupling Trap," showing that dimension-wise or patch-wise transport factorizations silently destroy the joint distribution of the data. All experiments are on synthetic complex fields.
Related papers
- Same Flow, Different Paths: Variance Reduction in Flow Matching [67.12978375116599]
We study the choice of this path from an optimization perspective.<n>Our main finding is that the choice of path $g_t$ can fundamentally change the convergence rate of SGD.
arXiv Detail & Related papers (2026-09-15T15:01:04Z) - Restricted Eigenvalues Beyond Gaussian Width: Threshold Occupancy under Heavy Tails [47.36630149538994]
For isotropic sub-Gaussian measurements, the benchmark sample size is $1+w(A)2$, where $w(A)$ is the Gaussian width of the normalized descent cone.<n>We give an explicit and systematic negative answer to the general question as formulated there: the proposed law fails in its full dimension-free, arbitrary-set form.<n>Under isotropy, a distribution-free fallback governed by affine dimension times squared enclosing radius is sharp on this family.
arXiv Detail & Related papers (2026-09-03T08:05:05Z) - Testing edge chirality with a three-path fractional quantum Hall interferometer [0.0]
We propose an average-current interferometer for the directional causal response of fractional quantum Hall edges.<n>Three coherent quantum point contacts (QPCs) form a flux-enclosing loop, so the leading Aharonov-Bohm harmonic is cubic in tunneling.
arXiv Detail & Related papers (2026-07-27T13:56:36Z) - Complex spacing ratio statistics in the partially open asymmetric quantum baker map [36.94429692322632]
We study the complex eigenvalue statistics of the asymmetric quantum baker map with partial projective openings.<n>We find a smooth crossover from a quasi-1D spectral regime, where eigenvalues cluster near the unit circle and the phase distribution of $z$ is peaked.<n>Both the number of open channels $M$ and the reflectivity $$ modulate this crossover, and $$ provides an additional continuous control even at fixed opening size.
arXiv Detail & Related papers (2026-07-08T19:24:35Z) - SILAGE: Memory-Efficient, Full-Gradient-Free Nonconvex Optimization for Nested Finite Sums [51.49970814177172]
Empirical risk on datasets naturally exhibits similarities in $N=nm$ total samples.<n>We provide an analysis that avoids pessimistic convergence analysis.<n>Our results improve existing state-of-the-art regimes.
arXiv Detail & Related papers (2026-06-14T14:11:07Z) - Efficient Mean Curvature Computation on High-Dimensional Data Manifolds [52.452902154360565]
Estimating local mean curvature at each point of a high-dimensional dataset is a key ingredient of machine learning algorithms.<n>This paper introduces two complementary contributions that together reduce this cost by several orders of magnitude.<n> Experiments on real-world datasets confirm speedups of 50 to 300 times relative to the original implementation.
arXiv Detail & Related papers (2026-06-04T16:04:31Z) - OAM-Induced Lattice Rotation Reveals a Fractional Optimum in Fault-Tolerant GKP Quantum Sensing [0.0]
We establish that orbital-angular-momentum encoding and Gottesman-Kitaev-Preskill (GKP) lattice geometry are structurally coupled.<n>Using an end-to-end differentiable Strawberry Fields--TensorFlow circuit, we jointly optimise $ell$, the lattice aspect ratio $r$, and the finite-energy envelope $$ to maximise quantum Fisher information.
arXiv Detail & Related papers (2026-05-13T09:49:16Z) - Bounds on Lorentz-violating parameters in magnetically confined 2D systems: A phenomenological approach [0.0]
We present a framework to constrain minimal SME coefficients $a_mu$ and $b_mu$ using magnetically confined two-dimensional electron systems.<n>Working in the nonrelativistic (Schr"odinger--Pauli) limit with effective mass, we derive the radial problem for cylindrical geometries.
arXiv Detail & Related papers (2025-10-28T11:11:59Z) - Mesoscopic Fluctuations and Multifractality at and across Measurement-Induced Phase Transition [46.176861415532095]
We explore statistical fluctuations over the ensemble of quantum trajectories in a model of two-dimensional free fermions.<n>Our results exhibit a remarkable analogy to Anderson localization, with $G_AB$ corresponding to two-terminal conductance.<n>Our findings lay the groundwork for mesoscopic theory of monitored systems, paving the way for various extensions.
arXiv Detail & Related papers (2025-07-15T13:44:14Z) - A Fourier Approach to Mixture Learning [46.995354373649675]
We give an algorithm that efficiently learns the means in $d = O(log k/loglog k)$ dimensions under separation $d/sqrtlog k (modulo factors)
Our results can be easily extended to learning mixtures of non-Gaussian distributions, under a mild condition on the Fourier spectrum of the distribution.
arXiv Detail & Related papers (2022-10-05T17:35:46Z) - A Law of Robustness beyond Isoperimetry [84.33752026418045]
We prove a Lipschitzness lower bound $Omega(sqrtn/p)$ of robustness of interpolating neural network parameters on arbitrary distributions.
We then show the potential benefit of overparametrization for smooth data when $n=mathrmpoly(d)$.
We disprove the potential existence of an $O(1)$-Lipschitz robust interpolating function when $n=exp(omega(d))$.
arXiv Detail & Related papers (2022-02-23T16:10:23Z) - A New Framework for Variance-Reduced Hamiltonian Monte Carlo [88.84622104944503]
We propose a new framework of variance-reduced Hamiltonian Monte Carlo (HMC) methods for sampling from an $L$-smooth and $m$-strongly log-concave distribution.
We show that the unbiased gradient estimators, including SAGA and SVRG, based HMC methods achieve highest gradient efficiency with small batch size.
Experimental results on both synthetic and real-world benchmark data show that our new framework significantly outperforms the full gradient and gradient HMC approaches.
arXiv Detail & Related papers (2021-02-09T02:44:24Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.