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REVIEW 4 major objections 6 minor 24 references

Learning Energy-Based Generative Models via Potential Flow: A Variational Principle Approach to Probability Density Homotopy Matching

T0 review · 4 major / 6 minor · reviewed 2026-08-16 · deepseek-v4-flash

Pith's one-line read VPFB trains an energy-based model by matching a potential-flow density path to the data, replacing MCMC negative sampling with a variational Poisson-equation loss.

desk verdict A promising MCMC-free EBM training scheme that earns referee time, but the central theoretical claim overreaches: Prop. 3 assumes the homotopy equality it needs to prove, and the implemented loss differs from the proved one. read the letter →

arxiv 2504.16262 v1 pith:JIAAJB5L submitted 2025-04-22 cs.LG

classification cs.LG
keywords energy-basedmodelspotentialflowdensityhomotopyDeepRitzmethodvariationalprinciplematchingPoissonequationout-of-distributiondetection
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

VPFB (Variational Potential Flow Bayes) aims to show that an energy-based generative model can be trained without the contrastive MCMC sampling that makes standard EBMs unstable and expensive. The method learns a scalar potential whose gradient pushes particles from a Gaussian prior to the data, and insists that the evolving density of this flow match a prescribed interpolating path between prior and data. The paper recasts that matching as a density-weighted Poisson equation and then as a Deep Ritz variational loss, a covariance between the potential and an innovation term plus an expected gradient-norm penalty, so training becomes plain gradient descent. If the argument holds, the steady-state potential is a genuine Boltzmann energy: the same network that generates samples also ranks inputs for out-of-distribution detection, and no auxiliary generator or MCMC warm-up is needed during training.

What carries the argument

The argument is carried by three linked objects. First, the conditional density homotopy $\rho(x|\bar{x},t) \propto \exp(\alpha(t)\log q(x) + \beta(t)\log p(\bar{x}|x))$, which the paper shows is a Gaussian perturbation kernel $\mathcal{N}(\mu(t)\bar{x}, \sigma(t)^2 I)$ interpolating between a Gaussian prior and the data-conditioned posterior; marginalizing it over data defines the target path $\bar{\rho}(x,t)$. Second, the density-weighted Poisson equation $\nabla\cdot(\bar{\rho}\nabla\Phi) = \frac12\,\mathbb{E}_{p_{\text{data}}}[\rho(\gamma-\bar{\gamma})]$, which encodes equality of the flow-driven density and the target homotopy, with innovation term $\gamma = (\dot{\alpha}/\omega^2)\|x\|^2 + (\dot{\beta}/\nu^2)\|x-\bar{x}\|^2$ centered at its conditional mean $\bar{\gamma}$. Third, the Deep Ritz loss $L(\Phi,t) = \operatorname{Cov}_{\rho p_{\text{data}}}[\Phi,\gamma] + \mathbb{E}_{\bar{\rho}}[\|\nabla\Phi\|^2]$, whose first-order optimality condition reproduces the weak form of the Poisson equation; a Poincar\'e-type spectral gap is invoked to guarantee a unique minimizer. The Boltzmann energy identity $\Phi_B = (4\Phi_\infty + f_\infty\|x\|^2)/g_\infty^2$ then connects the steady-state potential to the EBM likelihood, and the implemented training loss adds a cosine alignment term between $\nabla\Phi$ and the flow-matching conditional vector field plus a quasi-static penalty on $\partial\Phi/\partial t$.

What would settle it

On a low-dimensional target with a known density, such as a Gaussian mixture in two dimensions, train VPFB and then estimate the true density of the ODE-transported particles at several intermediate times by histogram or kernel binning; if the KL divergence between that measured flow density and the analytic marginal homotopy $\bar{\rho}(x,t)$ does not decrease toward zero as the Deep Ritz loss is minimized, the equivalence claimed in Proposition 3 is contradicted. A second, cheaper check: evaluate the residual of the density-weighted Poisson equation using the learned $\Phi$ and Monte Carlo estimates of the innovation expectation; a nonzero residual at the converged loss minimum would show the variational loss is not solving the PDE it claims to solve.

Watch

Extended reading notes

Core claim

VPFB's central claim is that training an energy-based generative model reduces to a variational-principle problem: rather than sampling negative examples with MCMC, one learns a potential $\Phi(x,t)$ whose gradient field transports a Gaussian prior along a density path that matches a prescribed homotopy to the data. The paper proves (Propositions 3 and 6) that solving the density-weighted Poisson equation $\nabla\cdot(\bar{\rho}\nabla\Phi) = \frac12\,\mathbb{E}[\rho(\gamma-\bar{\gamma})]$ is equivalent to minimizing the KL divergence between the flow-driven density and the target marginal homotopy, and that this is in turn equivalent to minimizing a Deep Ritz loss consisting of a covariance between the potential and the innovation $\gamma$ plus the expected squared gradient norm. At stationarity (Proposition 5), the same potential parameterizes a Boltzmann energy $\Phi_B = (4\Phi_\infty + f_\infty\|x\|^2)/g_\infty^2$, so the trained network is simultaneously a sampler and an energy surface for OOD detection. Training freezes the flow near the terminal time and treats the truncated marginal as the data distribution, making the Boltzmann form hold by construction rather than by demonstrated convergence.

Load-bearing premise

The load-bearing premise is that the flow-driven density already equals the target marginal homotopy: the proof of Proposition 3 derives the density-weighted Poisson equation from the KL objective only after assuming $\rho_\Phi(x,t) \equiv \bar{\rho}(x,t)$, the very equality the training is supposed to produce, and the stationarity claim similarly treats the truncated marginal at $t_{\max}$ as the data distribution by construction.

Editorial extensions

If this is right

  • EBM training reduces to a gradient-descent objective, a covariance loss plus gradient-norm penalty, with no MCMC negative sampling, so the main cost and instability of contrastive divergence disappears.
  • The trained potential is an explicit Boltzmann energy: the same network generates samples by ODE or SGLD and assigns energies that separate in-distribution from out-of-distribution inputs, as the paper's AUROC experiments demonstrate.
  • Because the training path is the optimal-transport flow-matching schedule, particle trajectories are nearly straight, so deterministic ODE sampling reaches competitive FID (6.72 on CIFAR-10 for the time-varying model) at a fraction of the training cost of the MCMC-based EBM baselines reported in the paper.
  • The MCMC-free promise applies to training: at inference, long-run deterministic ODE sampling drifts into visual artifacts in high dimensions, and the paper finds that stochastic SGLD sampling from the learned Boltzmann energy is what reaches the steady-state equilibrium.
  • Compositional generation becomes energy averaging: conditioning on a combination of attributes is approximated by averaging conditional potentials, which the paper demonstrates on CelebA attribute pairs.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • If Proposition 3's equivalence is as general as stated, the same variational principle should transfer to other perturbation kernels, such as heat-equation blurring or general linear corruptions, by recomputing the innovation term; the paper points to Neumann-boundary blurring kernels as future work, but the variational structure suggests the swap is mechanical.
  • The Boltzmann interpretation stands or falls with how close the truncated marginal $\bar{\rho}(x,t_{\max})$ is to the data; the paper's AUROC scores vary noticeably across OOD datasets, suggesting the energy's discriminative strength is dataset-dependent in a way the proof does not quantify.
  • The added cosine-alignment and quasi-static terms in the implemented loss go beyond the variational derivation, so the learned $\Phi$ is a Boltzmann energy only up to how strongly these extra terms perturb the minimizer; an ablation at fixed FID that isolates their effect on the energy's equilibrium behavior would clarify their role.
  • Because the covariance loss ties the energy magnitude to the residual of a Gaussian fit, the framework may be sensitive to the Gaussianity of the conditional path; extending the SDE formulation to non-Gaussian or learned priors, which the paper flags as a limitation, would test whether the energy-based interpretation survives beyond unimodal Gaussian transport.
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Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

4 major / 6 minor

Summary. The paper proposes Variational Potential Flow Bayes (VPFB), a framework for training energy-based generative models without contrastive divergence or auxiliary networks. The method parameterizes a potential flow Phi(x,t) and aims to match the flow-driven density homotopy to a data-recovery marginal homotopy built from Gaussian perturbation kernels. The authors derive a density-weighted Poisson equation (Eq. 14) as a stationarity condition, reformulate it as a Deep Ritz / covariance variational loss (Eq. 22), and claim that at stationarity the learned potential equals a Boltzmann energy (Eq. 20) usable for generation, interpolation, compositional generation, and OOD detection. Experiments on 2D synthetic densities, CIFAR-10, and CelebA report competitive FID and AUROC scores, with additional ablations and efficiency comparisons in the appendices.

Significance. If the theoretical claims were fully established, VPFB would be a significant contribution: it offers a sampling-free training objective for explicit EBMs, an interpretable energy landscape, OOD detection as a by-product, and a clear connection between potential flow and diffusion/flow-matching theory. The use of the Deep Ritz method for a density-weighted Poisson equation in generative modeling is novel and interesting. The paper is also unusually honest about its limitations, including long-run ODE divergence, the need for SGLD at inference, and the trade-off between Boltzmann stationarity and sample quality. However, the central theoretical bridge is currently not proven: Proposition 3's proof assumes the homotopy equality it is meant to establish, stationarity is enforced by construction in Section 3.5, and the implemented loss (25) differs from the analyzed loss (22). These gaps mean the paper's headline claims outrun the supporting theory, and the empirical results lack repeated-run statistics. The idea is promising and the empirical core may be salvageable, but substantial revision is required.

major comments (4)
  1. [Section 3.2 / Appendix C.3, Eq. (61)] Proposition 3's equivalence claim between solving the density-weighted Poisson equation (14) and minimizing the KL divergence D_KL[rho_Phi || rho_bar] is not established. In the proof of Proposition 3, the first variation of the one-step KL is computed for a general rho_Phi, but equation (61) then substitutes rho_Phi(x,t) ≡ rho_bar(x,t) before deriving the Poisson equation. Consequently, equation (14) is a local condition that preserves homotopy matching provided the flow density is already on the target marginal; the proof does not show that minimizing the loss in (22) contracts the KL when rho_Phi differs from rho_bar, which is precisely the situation during training of a finite-capacity network. This is load-bearing because the paper uses Proposition 3 to claim that the variational loss minimizes KL divergence between homotopies (see Section 3.4 and the remark following Proposition 6). The authors should either prove a contraction or bound for the KL under the proposed loss, or explicitly restate Proposition 3 as a preservation property and temper the framing accordingly.
  2. [Section 3.5, Eq. (20)] The stationary Boltzmann equilibrium is imposed by fiat: the text sets p_infinity(x) = rho_bar(x, t >= t_max) ≈ p_data(x) and then equates this to the Boltzmann distribution. As written, 'the stationary Boltzmann distribution approximates the true data likelihood by design', so the learned energy approximates the data by construction rather than by convergence of the learning procedure. Proposition 5's conclusion is therefore conditional on an assumption that is not derived from the flow-matching dynamics and is not empirically verified. This is load-bearing for the claim that VPFB learns an explicit EBM whose energy is a valid OOD score. The authors should provide a quantitative assessment of the discrepancy between rho_bar(x, t_max) and p_data (for example, an FID or likelihood evaluation of the marginal at the cutoff), or clearly label the stationarity enforcement as an additional modeling assumption separate from the theoretical claims.
  3. [Section 3.4-3.5, Eqs. (22) and (25)] The implemented loss (25) differs from the theoretically analyzed loss (22) by the cosine alignment term, the Poincare regularization η||Phi||^2, the time-derivative penalty, and the weighting w(t). No theorem connects this full implemented loss to the weak formulation (21) or to the KL minimization claim of Proposition 3. The cosine term, in particular, changes the scale-invariance properties of the objective, and the Poincare penalty changes the minimizer of the variational problem. The ablation study in Table 3 shows these terms are empirically important, but the theory section only covers loss (22). As a result, the claim that the actual training procedure optimizes the proposed KL/Deep Ritz objective is unsupported. The authors should either extend the theoretical analysis to the full loss (25) or explicitly present (25) as an empirically motivated modification whose relationship to (22) is to be established.
  4. [Tables 1 and 2] The paper reports single FID and AUROC values without standard deviations or multiple seeds. FID estimates are known to be noisy, and several reported margins over competitors are small (for example, VPFB's FID 6.72 versus Flow Matching's 6.35, or AUROC 0.78 versus CDRL's 0.75 on CIFAR-10). The checkpoint selection rule (lowest FID on a validation subset, per Appendix D.5) further biases the reported numbers. Since the empirical claims of competitiveness are a major part of the paper's contribution, the authors should provide means and standard errors over at least three independent training runs, or clearly state that the results are single-run and interpret them as preliminary without strong comparative statements.
minor comments (6)
  1. [Eq. (25)] The gradient-norm term in Eq. (25) writes ∇_{(x,t)}Phi, which appears to be a typo for ∇_x Phi; in addition, the time-derivative penalty mentioned in the text is not explicitly displayed in the equation.
  2. [Section 3.2 / Appendix C.3] The notation for the Sobolev space is inconsistent: Proposition 3 states Phi in H^1_0(Ω,p) while the text earlier defines H^n_0; please harmonize the notation throughout.
  3. [Eq. (16)] The diffusion coefficient formula g(t) = -√(2σ(t)(σ̇(t)+f(t)σ(t))) carries a minus sign outside the square root; since g is conventionally positive, please verify the sign convention and define the square-root branch explicitly.
  4. [Figure 10] The caption should clarify that the plotted ratio is measured while training without the Poincare regularization, whereas the final models include the Poincare penalty; as written, the figure may be misinterpreted as validating the final loss.
  5. [Table 1] The column header 'Other Likelihood-based Models' includes GAN-based models such as SN-GAN and BigGAN, which are not likelihood-based; please reorganize the table or adjust the caption to avoid confusion.
  6. [Appendix D.2 and D.3] The training setup states a terminal time of tend = 1, while Appendix D.3 states that best ODE sampling results use tend = 1.575; please clarify the distinction between training and sampling time horizons.

Circularity Check

2 steps flagged · score 7.0 of 10

Proposition 3's proof assumes the homotopy equality it claims to derive, and Section 3.5 imposes the Boltzmann stationary state by defining p∞(x) = ρ̄(x,t≥tmax) ≈ p_data.

  1. self definitional [Appendix C.3, after Eq. (61) in the proof of Proposition 3]
    "where we have assumed that ρΦ(x,t)≡¯ρ(x,t) holds and have used the following identities:"

    Proposition 3 is the load-bearing claim that solving the density-weighted Poisson equation (14) is equivalent to minimizing DKL[ρΦ∥ρ̄], and Proposition 6 then links loss (22) to that equation. In the proof, after deriving the first variation for a general trial direction, the text substitutes ρΦ(x,t)≡ρ̄(x,t) before obtaining the PDE. With the base case ρΦ(x,0)=ρ̄(x,0), this gives only a local preservation result: if the flow density is already on the target homotopy, the constructed velocity keeps it there. It does not show that the loss contracts the KL divergence when ρΦ differs from ρ̄, which is precisely the finite-capacity network / SGD situation.

  2. fitted input called prediction [Section 3.5, Training Implementation]
    "we explicitly enforce stationarity in our training implementation, by imposing a steady-state equilibrium p∞(x) = ¯ρ(x,t≥tmax) ... This steady-state equilibrium p∞(x)≡pB(x) thus corresponds to the stationary Boltzmann distribution ... Given that a steady-state equilibrium is enforced via p∞(x) = ¯ρ(x,t≥tmax)≈pdata(¯x), the stationary Boltzmann distribution approximates the true data likelihood by design."

    The paper's advertised connection between the learned potential and the Boltzmann energy (20) rests on the marginal homotopy reaching a stationary equilibrium. The text concedes that ρ̄ is not guaranteed to reach equilibrium within the flow's finite time window, and then fixes the gap by declaring p∞(x) = ρ̄(x,t≥tmax) ≈ p_data. Since the stationary density is set equal to the schedule's terminal marginal and asserted to approximate p_data by design, the Boltzmann energy Φ_B is tied to the chosen schedule by construction rather than being a converged prediction of the homotopy-matching loss. The central claim that VPFB learns a stationary Boltzmann energy is therefore partly an enforced definition, not an independently derived consequence.

full rationale

The paper does contain a genuinely meaningful independent ingredient: the Deep Ritz / covariance-plus-gradient loss (22) is a legitimate variational form for the density-weighted Poisson equation, and the experiments are benchmarked against external methods rather than only against the authors' own outputs. No load-bearing self-citation chain or imported uniqueness theorem from the same authors appears. However, the theoretical bridge from the KL objective to the implemented loss is broken by two explicit insertions. In the proof of Proposition 3, the equality ρΦ≡ρ̄ is assumed at Eq. (61) before the Poisson equation is derived, so the proof establishes only preservation of an already-assumed matching, not convergence of the KL objective from a mismatched density. In Section 3.5, stationarity is imposed by fiat: p∞(x) is defined as ρ̄(x,t≥tmax) and then taken to approximate p_data, making the Boltzmann energy approximate the data by construction. Because these two steps are located on the central derivation path from the variational principle to the claimed EBM/Boltzmann result, the core theoretical claim is partially circular, even though the empirical evaluation and the Deep Ritz formulation retain independent value. A score of 7 reflects this partial but central circularity; it is not a case of mere incidental self-citation.

Assumptions & free parameters 6 free parameters · 6 assumptions · 0 invented entities

The central construction rests on Gaussian prior and likelihood choices, boundary decay, a spectral-gap inequality, an enforced steady state, and, in the proof of Proposition 3, the very matching it aims to establish. No genuinely new physical entities are introduced.

free parameters (6)
  • OT-FM mean schedule mu(t) = t
    Linear interpolation path between noise and data is a modeling choice, not derived from data.
  • OT-FM standard deviation schedule sigma(t) = 1 - t
    Defines the Gaussian perturbation kernel and the effective noise level at each time.
  • Cutoff time t_max = 1 - 1e-5
    Stationarity is enforced for t >= t_max, which is central to the Boltzmann energy claim.
  • Decay exponent kappa = 1.5
    Weights the innovation term in the covariance loss to stabilize training.
  • Poincare spectral gap constant eta = 1e-4 (fine-tuned)
    Added as a regularization term; the paper states its existence varies across architectures.
  • SGLD temperature lambda = 0.35
    Required for convergent stochastic sampling in the long-run equilibrium experiments.
assumptions (6)
  • standard math Flow density evolves by the continuity equation (12).
    Standard advection result used throughout Section 3.2.
  • domain assumption The prior is a unimodal Gaussian q(x) = N(0, omega^2 I).
    Required for consistency with the diffusion SDE and ODE; the authors acknowledge this limitation in Section 4.1.
  • domain assumption The marginal density rho_bar vanishes on the boundary of the domain.
    Remark 1 invokes exponential decay of the Gaussian kernel, but the neural energy is trained on compact normalized data and boundary behavior is not directly enforced.
  • domain assumption The Poincare inequality holds with a positive constant eta.
    Needed for uniqueness of the variational solution; the empirical check in Figure 10 is on one model and the paper reports architecture dependence.
  • ad hoc to paper Stationary equilibrium can be enforced by setting p_infinity(x) = rho_bar(x, t >= t_max) approximately p_data.
    This makes the Boltzmann distribution approximate the data by construction rather than by convergence.
  • ad hoc to paper The flow-driven density equals the target marginal homotopy inside the proof of Proposition 3.
    The proof in Appendix C.3 assumes rho_Phi = rho_bar to derive the Poisson equation, which is the matching result being claimed.

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Pith. "Pith review of Learning Energy-Based Generative Models via Potential Flow: A Variational Principle Approach to Probability Density Homotopy Matching." pith.science (2026). https://pith.science/paper/JIAAJB5L

@misc{pith2026250416262,
  author       = {Pith},
  title        = {Pith review of: Learning Energy-Based Generative Models via Potential Flow: A Variational Principle Approach to Probability Density Homotopy Matching},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/JIAAJB5L}},
  note         = {Machine review of arXiv:2504.16262}
}
read the original abstract

Energy-based models (EBMs) are a powerful class of probabilistic generative models due to their flexibility and interpretability. However, relationships between potential flows and explicit EBMs remain underexplored, while contrastive divergence training via implicit Markov chain Monte Carlo (MCMC) sampling is often unstable and expensive in high-dimensional settings. In this paper, we propose Variational Potential Flow Bayes (VPFB), a new energy-based generative framework that eliminates the need for implicit MCMC sampling and does not rely on auxiliary networks or cooperative training. VPFB learns an energy-parameterized potential flow by constructing a flow-driven density homotopy that is matched to the data distribution through a variational loss minimizing the Kullback-Leibler divergence between the flow-driven and marginal homotopies. This principled formulation enables robust and efficient generative modeling while preserving the interpretability of EBMs. Experimental results on image generation, interpolation, out-of-distribution detection, and compositional generation confirm the effectiveness of VPFB, showing that our method performs competitively with existing approaches in terms of sample quality and versatility across diverse generative modeling tasks.

Figures

Figures reproduced from arXiv: 2504.16262 by the authors.

Figure 1
Figure 1. 2D potential flow. Top: Sample trajectories from the Gaussian prior noise distribution (black) to [PITH_FULL_IMAGE:figures/full_fig_p009_1.png] view at source ↗
Figure 2
Figure 2. 2D Boltzmann density estimation. Top: Sample trajectories from the Gaussian prior noise distri [PITH_FULL_IMAGE:figures/full_fig_p010_2.png] view at source ↗
Figure 3
Figure 3. Uncurated and unconditional samples generated for CIFAR-10 (left) and CelebA (right). [PITH_FULL_IMAGE:figures/full_fig_p011_3.png] view at source ↗
Figures from the paper (19 more)
Figure 4
Figure 4. Figure 4: Compositional and conditional CelebA samples generated based on three attribute pairs. [PITH_FULL_IMAGE:figures/full_fig_p011_4.png]
Figure 5
Figure 5. Figure 5: Generated CIFAR-10 samples and their five nearest neighbors in train set based on pixel distance. [PITH_FULL_IMAGE:figures/full_fig_p012_5.png]
Figure 6
Figure 6. Figure 6: Additional uncurated samples on unconditional CIFAR-10 [PITH_FULL_IMAGE:figures/full_fig_p035_6.png]
Figure 7
Figure 7. Figure 7: Additional uncurated samples on unconditional CelebA [PITH_FULL_IMAGE:figures/full_fig_p036_7.png]
Figure 8
Figure 8. Figure 8: Additional interpolation results on unconditional CIFAR-10 [PITH_FULL_IMAGE:figures/full_fig_p037_8.png]
Figure 9
Figure 9. Figure 9: Additional interpolation results on unconditional CelebA [PITH_FULL_IMAGE:figures/full_fig_p038_9.png]
Figure 10
Figure 10. Figure 10: Validation of a Poincaré lower bound using the ratio of the gradient norm to the energy norm on [PITH_FULL_IMAGE:figures/full_fig_p039_10.png]
Figure 11
Figure 11. Figure 11: Histogram of the energy-parameterized density estimates for the CIFAR-10 training and test [PITH_FULL_IMAGE:figures/full_fig_p039_11.png]
Figure 12
Figure 12. Figure 12: Long-run ODE (RK45) sampling using autonomous potential energy [PITH_FULL_IMAGE:figures/full_fig_p039_12.png]
Figure 13
Figure 13. Figure 13: Long-run ODE (RK45) sampling using time-varying potential energy [PITH_FULL_IMAGE:figures/full_fig_p040_13.png]
Figure 14
Figure 14. Figure 14: Validation of the convergence of gradient norm and energy norm in long-run ODE (RK45) [PITH_FULL_IMAGE:figures/full_fig_p040_14.png]
Figure 15
Figure 15. Figure 15: Long-run SGLD sampling using the Boltzmann energy with [PITH_FULL_IMAGE:figures/full_fig_p041_15.png]
Figure 16
Figure 16. Figure 16: Validation of the convergence of the gradient norm and the energy norm in long-run SGLD [PITH_FULL_IMAGE:figures/full_fig_p041_16.png]
Figure 17
Figure 17. Figure 17: Long-run SGLD sampling using the Boltzmann energy with [PITH_FULL_IMAGE:figures/full_fig_p042_17.png]
Figure 18
Figure 18. Figure 18: Validation of the convergence of the gradient norm and the energy norm in long-run SGLD [PITH_FULL_IMAGE:figures/full_fig_p042_18.png]
Figure 19
Figure 19. Figure 19: Long-run SGLD sampling using the Boltzmann energy on CIFAR-10 for loss configuration (D). [PITH_FULL_IMAGE:figures/full_fig_p043_19.png]
Figure 20
Figure 20. Figure 20: Validation of the convergence of gradient norm and energy norm in long-run SGLD sampling [PITH_FULL_IMAGE:figures/full_fig_p043_20.png]
Figure 21
Figure 21. Figure 21: Long-run SGLD sampling using the Boltzmann energy with loss configuration (E) on CIFAR-10. [PITH_FULL_IMAGE:figures/full_fig_p044_21.png]
Figure 22
Figure 22. Figure 22: Validation of the convergence of gradient norm and energy norm in long-run SGLD sampling [PITH_FULL_IMAGE:figures/full_fig_p044_22.png]

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    For an unnormal- ized solutionΦ(x), we can always obtain a normalization by subtracting its mean. The optimal solutionΦof the functional (84) is given by the first-order optimality condition: I(Φ,Ψ) = d dϵL(Φ(x) +ϵΨ(x),t) ⏐⏐⏐⏐ ϵ=0 = 0(85) which must hold for all trial function...

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Reviewed August 16, 2026 · model on record in the stance chip above.