Schedule

Monday: Foundations of Deep Learning

  • 11:00 – 13:00: Introduction to Deep Learning (Lecture)
    • The Deep Learning Revolution & Motivation
    • Deep Learning Primitives: Architectures & Activations
      • Neural Network Architectures: From the Perceptron to MLPs
      • Activation Functions (ReLU, Sigmoid, Softmax, etc.)
    • Convolutional Neural Networks (CNNs)
      • Discrete Convolutions and Cross-Correlation
      • Pooling, Subsampling, and Receptive Fields
    • Advanced Architectures: ResNets and UNets
      • Skip Connections and Residual Networks
      • Encoder-Decoder Structures
    • Training Dynamics & Optimisation
      • Loss Functions (MSE, Cross-Entropy)
      • Gradient Descent, SGD, and Adam Optimiser
      • Practical Training Considerations: Dropout, Batch Normalisation, Weight Decay, Learning Rate Scheduling
    • The Chain Rule of Calculus & Backpropagation
      • Classical Backpropagation Recursions
      • Generalisation to Implicit Operators: Bilevel, Fixed-Point, and Continuous Limits
    • Direct Supervised Learning (End-to-End) & Its Pitfalls
      • Data Consistency Problem
      • Lipschitz Dilemma and Adversarial Vulnerability
      • Opaque Implicit Bias
  • 13:00 – 14:00: Lunch
  • 14:00 – 16:00: Introduction to the Coding Challenge (Practice)
    • Problem Statement: Restoring high-quality images from motion blur and noise
    • Software Stack: PyTorch, DeepInverse (deepinv)
    • Baseline Implementation: Mathematical reconstruction method (classical inverse problem approach)
    • Competition Details: Groups of 3–4; evaluate on hidden test set (PSNR/SSIM metrics); model size ≤ 100 MB; CPU inference within 20 minutes

Tuesday: Bilevel Optimisation and Unrolling

  • 11:00 – 13:00: Advanced Deep Learning for Inverse Problems (Lecture)
    • Recap: Inverse Problems & End-to-End Learning
      • The Inverse Problem Formulation ($y^\delta = Ax^\dagger + \eta$)
      • Pitfalls of End-to-End Learning Revisited
      • Classical Methods vs. Deep Learning Trade-offs
    • Null-Space Networks & Data Consistency
      • The Null Space of Forward Operators
      • Orthogonal Decomposition of Images ($\mathbb{R}^n = \mathcal{N}(A) \oplus \mathcal{R}(A^\top)$)
      • Null-Space Architecture: Enforcing Strict Data Consistency
      • Interpretability and Safety Guarantees
    • Variational Methods & Optimisation Algorithms
      • Inverse Problems as Variational (Regularised) Optimisation
      • Classical Regularisation Techniques
      • Iterative Algorithms: ISTA and PDHG
    • Bilevel Optimisation & Sensitivity Analysis
      • Formulating Hyper-Parameter Learning as Nested Optimisation
      • Introduction to Convex and Non-Convex Optimisation
      • Differentiating Through the Lower Level via the Implicit Function Theorem (IFT)
      • Handling Non-Smooth Functions via Huber Smoothing
    • Learning Regularisers with Guarantees
      • NETT (Network Tikhonov Regularisation)
      • ICNNs (Input Convex Neural Networks) for Recovering Stability Guarantees
    • The Unrolling Principle & Architectures
      • Truncating Iterative Algorithms to Fixed-Depth Learnable Networks
      • LISTA: Learned ISTA
      • Learned Primal-Dual (LPD) Networks as Unrolled PDHG
  • 13:00 – 14:00: Lunch
  • 14:00 – 16:00: ARC Forum and Social (Optional, no scheduled class)
    • 14:00 – 15:00: ARC weekly forum
    • 15:00 onwards: ARC social hour
    • No formal training session scheduled; attendees may join optional events

Wednesday: Modular Deep Learning and Generative Models

  • 11:00 – 13:00: Modular Deep Learning and Generative AI (Lecture)
    • Modular Deep Learning via Plug-and-Play (PnP)
      • Breaking the Rigidity of End-to-End and Unrolled Networks
      • The Plug-and-Play Heuristic: Replacing Proximal Operators with Pre-Trained Denoisers
      • PnP-HQS and PnP-ADMM Algorithms
      • Convergence Analysis: Fixed-Point Perspective (Non-Expansive and Contractive Denoisers, Banach's Theorem)
    • Defining Losses & The Jacobian Critique
      • Regularisation by Denoising (RED): Learning from Denoiser Implicit Priors
      • Critical Evaluation of Explicitly Defined Loss Functions
      • Jacobian Critique and its Implications
    • Deep Generative Modelling Frameworks
      • Autoencoders and Variational Autoencoders (VAEs)
        • Encoder–Decoder Structure and the Reparameterisation Trick
        • ELBO (Evidence Lower Bound) Objective
        • VAEs as Learned Latent-Space Priors
      • Generative Adversarial Networks (GANs) and Normalising Flows
    • Score-Based Models and Diffusion
      • From Denoisers to Probability Distributions: Tweedie's Formula
      • Denoising Score Matching
      • The Forward Diffusion Process and Reverse-Time SDE
      • Diffusion Models as Learned Priors for Inverse Problems
      • Langevin Dynamics and Sampling
      • Diffusion Posterior Sampling (DPS) for Solving Inverse Problems
  • 13:00 – 14:00: Lunch
  • 14:00 – 16:00: Coding Challenge (continued)
    • Continue working in groups on your coding challenge contributions.

Thursday: Continuous Depth and Implicit Deep Learning

  • 11:00 – 13:00: Continuous Depth and Implicit Deep Learning (Lecture)
    • Deep Learning as Continuous Dynamical Systems
      • ResNets as Forward Euler Discretisations of ODEs
      • Gradient Flow as Continuous Optimisation
      • Neural ODEs and Adaptive Computation
    • Discretisation and Architectural Design
      • From Continuous ODEs to Discrete Network Layers
      • Symplectic Discretisations for Energy-Stable Networks
      • Variational Networks (VNs): Incorporating Physics Through Discretisation Schemes
    • The Early Stopping Paradox & Dynamic Depth
      • Why Fixed Depth Leads to Suboptimality
      • Learning Depth as a Continuous Parameter
      • Resolving the Paradox: Adaptive Network Width and Depth
    • Implicit Deep Learning & Deep Equilibrium Models (DEQ)
      • Fixed-Point Problems and Implicit Function Theorem
      • DEQ Architecture: Single Fixed-Point Condition vs. Finite Layers
      • Memory-Efficient Training via Implicit Differentiation
      • Adjoint Equations for Implicit Backpropagation
    • Connection to Bilevel Learning
      • DEQs as Optimisation-Defined Layers (Bilevel Framework)
      • Implicit Differentiation for Hyperparameter Sensitivity
  • 13:00 – 14:00: Lunch
  • 14:00 – 16:00: Guest Lecture and Q&A
    • Speaker: Dr Jonas Latz, University of Manchester.
    • Topic: Stochastic gradient methods in continuous time for machine learning, including stochastic gradient processes, convergence and ergodicity, and implications for modern ML optimisation practice.
    • Q&A with the guest speaker.

Friday: Group Presentations

  • 10:00 – 12:30: Presentations
    • Student groups present their solution to the coding challenge.
    • Focus on: Architecture choice, training strategy, and evaluation of results (PSNR/SSIM).
  • 12:30 – 13:30: Lunch
  • 13:30: End of Training Week