What should a 24-year-old be learning?
At age 24, 141 topics open up across Science, Mathematics, Computing. Each one has prerequisites that come first, so the order matters more than the list: Characterisation Standards: What Counts as Proof of a New Compound is a typical starting point.
How do I know what a 24-year-old already knows?
LightMySky starts by assuming everything below the learner’s level is already known, then checks the assumption as they practise. What holds up stays lit; what does not comes back for review.
Science
- Characterisation Standards: What Counts as Proof of a New CompoundChemistry · on the way
- Chain Growth and Step Growth: Two Routes to a PolymerChemistry · on the way
- Choosing Between Vibrational Methods: Infrared, Raman and Resonance RamanChemistry · on the way
- Single-Crystal Diffraction: From Reflections to a Refined StructureChemistry · on the way
- Cross-Coupling in Practice: Choosing Ligand, Base and ConditionsChemistry · on the way
- Controlled Radical Polymerisation and Block ArchitectureChemistry · on the way
- Electron Correlation and Methods Past Hartree-FockChemistry · on the way
- Excited States by Calculation and Simulated Electronic SpectraChemistry · on the way
- Functionalising a Carbon-Hydrogen Bond Without a HandleChemistry · on the way
- Glass Transition, Crystallinity and Entanglement in PolymersChemistry · on the way
- Molecular Recognition: Preorganisation, Complementarity and Binding ConstantsChemistry · on the way
- Olefin Metathesis and Ring-Closing StrategyChemistry · on the way
- Photoredox and Electrochemical Routes to Radical IntermediatesChemistry · on the way
- Putting the Solvent Into a CalculationChemistry · on the way
- Molecular Dynamics and Free Energy from SamplingChemistry · on the way
- Reaction Dynamics: Trajectories Across a Potential Energy SurfaceChemistry · on the way
- Risk Assessment for a Reaction Nobody Has Run HereChemistry · on the way
- Self-Assembly: Templates, Reversibility and Error CorrectionChemistry · on the way
- Taking a Route into Flow and Onto ScaleChemistry · on the way
- Reading a Total Synthesis as an ArgumentChemistry · on the way
- Writing a Research Proposal: Question, Feasibility and MilestonesChemistry · on the way
- Reporting Chemical Data: Statistics, Figures and Data AvailabilityChemistry · on the way
- Ultrafast Spectroscopy and Watching a Reaction HappenChemistry · on the way
- Noether's Theorem: Symmetry and Conserved QuantitiesForces & Motion · on the way
- From Coordinates to Fields: the Lagrangian DensityForces & Motion · on the way
- Unitary Time Evolution and the Heisenberg PictureQuantum & Modern Physics · on the way
- Angular Momentum from Its Commutation RelationsQuantum & Modern Physics · on the way
- Adding Angular Momenta and the Coupled BasisQuantum & Modern Physics · on the way
- Identical Particles and the Symmetry of a Many-Body StateQuantum & Modern Physics · on the way
- Degenerate Perturbation Theory and the Variational MethodQuantum & Modern Physics · on the way
- The Path Integral and the Sum Over HistoriesQuantum & Modern Physics · on the way
- Time-Dependent Perturbation Theory and Fermi's Golden RuleQuantum & Modern Physics · on the way
- Scattering: Cross-Sections and the Born ApproximationQuantum & Modern Physics · on the way
- Density Matrices, Entanglement and the Bell TestQuantum & Modern Physics · on the way
- Field Quantisation: Creation Operators and Particle NumberQuantum & Modern Physics · on the way
- The Klein-Gordon and Dirac EquationsQuantum & Modern Physics · on the way
- Covariant Electrodynamics and the Field TensorElectricity & Magnetism · on the way
- Gauge Freedom and the Potentials as the Working VariablesElectricity & Magnetism · on the way
- Radiation from an Accelerating ChargeElectricity & Magnetism · on the way
- Fluctuations, Linear Response and the Fluctuation-Dissipation RelationThermal & Statistical Physics · on the way
- Phase Transitions, Order Parameters and Broken SymmetryThermal & Statistical Physics · on the way
- The Ising Model and the Mean-Field ApproximationThermal & Statistical Physics · on the way
- Critical Exponents, Scaling and UniversalityThermal & Statistical Physics · on the way
- Crystal Lattices, the Reciprocal Lattice and Bloch's TheoremMatter & Materials · on the way
- Phonons and the Heat Capacity of SolidsMatter & Materials · on the way
- Band Structure: Metals, Insulators and the GapMatter & Materials · on the way
- Semiconductors, Doping and the p-n JunctionMatter & Materials · on the way
- Superconductivity: the Meissner Effect and Cooper PairsMatter & Materials · on the way
- Tensors and the Metric on a Curved ManifoldAstronomy & Astrophysics · on the way
- Parallel Transport, Christoffel Symbols and the Geodesic EquationAstronomy & Astrophysics · on the way
- Curvature and the Einstein Field EquationAstronomy & Astrophysics · on the way
- The Schwarzschild Solution: Orbits, Redshift and the HorizonAstronomy & Astrophysics · on the way
- Linearised Gravity and Gravitational WavesAstronomy & Astrophysics · on the way
- Systematic Error, Controls and the Design of a MeasurementScientific Inquiry · on the way
- Reading a Paper: the Claim, the Evidence and the AssumptionScientific Inquiry · on the way
- Writing Physics: the Figure, the Error Bar and the Defensible ClaimScientific Inquiry · on the way
- From Hit to Lead: Structure-Activity RelationshipsChemistry · on the way
- Drug-Like Properties: Solubility, Permeability and Metabolic FateChemistry · on the way
- Chemical Biology: Bioconjugation and Reporting on a Molecule in a CellChemistry · on the way
- Bayesian Phylogenetics: Priors, Sampling and Judging ConvergenceGenetics & Evolution · on the way
- Phylogenomics: Gene Trees, Species Trees and Why They DisagreeGenetics & Evolution · on the way
- Differential Expression from Counts: Dispersion, Fit and ShrinkageGenetics & Evolution · on the way
- Testing Thousands of Genes at Once: False Discovery Rate and What q MeansGenetics & Evolution · on the way
- From a Gene List to Biology: Enrichment Tests and Their BackgroundsGenetics & Evolution · on the way
- Power and Effect Size, Decided Before the DataScientific Inquiry · on the way
- Researcher Degrees of Freedom and the Pre-registered Analysis PlanScientific Inquiry · on the way
- Reading a Primary Paper: The Claim, the Figure and the Missing ControlScientific Inquiry · on the way
- Reproducibility in Practice: Data, Code and What Another Lab Can RerunScientific Inquiry · on the way
- Mapping Regulatory Elements: Accessibility, Occupancy and ContactGenetics & Evolution · on the way
- Single-Cell Analysis: Normalisation, Embedding and Naming Cell StatesGenetics & Evolution · on the way
- Modelling a Biological System: Rate Equations, Parameters and FitGenetics & Evolution · on the way
- Genome Engineering: Cut Site, Repair Choice and Editing OutcomeGenetics & Evolution · on the way
- Ethics of Emerging Biotechnology: Editing, Enhancement and BiosecurityScientific Inquiry · on the way
- Base and Prime Editing: Changing a Letter Without Breaking Both StrandsGenetics & Evolution · on the way
- Pooled Genetic Screens: Library Design, Selection and Reading a Hit ListGenetics & Evolution · on the way
- Synthetic Circuits: Switches, Oscillators and Why They Misbehave in CellsMicrobiology · on the way
- Metabolic Engineering: Redirecting Flux Through a Production HostMicrobiology · on the way
- Proteomics: Mass Spectra, Quantification and Interaction MapsBiochemistry & Molecular Biology · on the way
- The Tumour Microenvironment: Stroma, Hypoxia and Immune ExclusionOrganisms & Life Processes · on the way
- Targeted Therapy and the Resistance That Follows ItOrganisms & Life Processes · on the way
- Checkpoint Blockade: Taking a Brake Off a T CellThe Human Body · on the way
- Clinical Trials: Phases, Endpoints and Why Most Candidates FailThe Human Body · on the way
- Engineered Cell Therapy: Receptor Design, Manufacture and ToxicityThe Human Body · on the way
- Target Validation and Lead Discovery: From a Biological Claim to a MoleculeBiochemistry & Molecular Biology · on the way
- The Host Microbiome: Composition, Causation and InterventionMicrobiology · on the way
Mathematics
- Monotone Convergence, Fatou and Dominated ConvergenceCalculus & Analysis · on the way
- Product Measure and Fubini's TheoremCalculus & Analysis · on the way
- Lp Spaces and the Inequalities They Rest OnCalculus & Analysis · on the way
- Normed Spaces, Completeness and Banach SpacesCalculus & Analysis · on the way
- Bounded Linear Operators and the Operator NormCalculus & Analysis · on the way
- Baire Category and the Uniform Boundedness PrincipleCalculus & Analysis · on the way
- The Hahn-Banach Theorem and the Dual SpaceCalculus & Analysis · on the way
- Hilbert Spaces and Orthogonal Projection in Infinite DimensionsCalculus & Analysis · on the way
- Compact Self-Adjoint Operators and the Spectral TheoremCalculus & Analysis · on the way
- Convolution, Plancherel and Transforming a DerivativeCalculus & Analysis · on the way
- Weak Solutions and Test FunctionsDifferential Equations · on the way
- Markov Chains and the Memoryless AssumptionProbability · on the way
- Stationary Distributions and Long-Run BehaviourProbability · on the way
- Martingales and Optional StoppingProbability · on the way
- Brownian Motion and Its Defining PropertiesProbability · on the way
- Conditioning, Stability and Floating-Point ErrorCalculus & Analysis · on the way
- Iterative Methods for Large Linear SystemsLinear Algebra · on the way
- Numerical Schemes for Evolution EquationsDifferential Equations · on the way
- Polynomial Rings, Irreducibility and Unique FactorisationAbstract Algebra · on the way
- Modules: Linear Algebra Over a RingAbstract Algebra · on the way
- Field Extensions and Their DegreesAbstract Algebra · on the way
- The Galois CorrespondenceAbstract Algebra · on the way
- Characters and the Orthogonality RelationsAbstract Algebra · on the way
- Decomposing a Representation from Its CharacterAbstract Algebra · on the way
- Topological Spaces: Continuity Without DistanceTopology · on the way
- Definitions as Design DecisionsMathematical Thinking · on the way
- Counterexamples and Testing a ConjectureMathematical Thinking · on the way
- Open Problems as a GenreMathematical Thinking · on the way
- Compactness and ConnectednessTopology · on the way
- The Fundamental Group and Loops on a CircleTopology · on the way
Computing
- Complexity Beyond NP: Space, Randomness and the HierarchyAlgorithms & Data Structures · on the way
- SAT Solvers and What Makes Search PracticalAlgorithms & Data Structures · on the way
- Adapting a Pretrained Model: Fine-Tuning and Low-Rank UpdatesMachine Learning · on the way
- Generative Models: Learning a Distribution You Can SampleMachine Learning · on the way
- Diffusion Models: Learning to Undo NoiseMachine Learning · on the way
- Markov Decision Processes: States, Actions and ReturnMachine Learning · on the way
- Temporal-Difference Learning and Q-LearningMachine Learning · on the way
- Policy Gradients and the Actor-Critic SplitMachine Learning · on the way
- Learning from Human Preferences: Reward Models and Policy OptimisationMachine Learning · on the way
- Training Across Many Devices: Data, Model and Pipeline ParallelismMachine Learning · on the way
- Serving a Model: Batching, the Key-Value Cache and QuantisationMachine Learning · on the way
- Distributed Transactions and the Blocking Case of Two-Phase CommitData & Databases · on the way
- Conflict-Free Replicated Data TypesData & Databases · on the way
- Log-Structured Storage and CompactionData & Databases · on the way
- Stream Processing: Windows, Watermarks and Late EventsData & Databases · on the way
- Cloud-Native Architecture: Containers, Schedulers and the Control LoopComputer Systems · on the way
- Observability and Tail Latency Across ServicesComputer Systems · on the way
- Benchmarks and the Traps in ThemMachine Learning · on the way
- Specifying Correctness: Safety, Liveness and InvariantsSoftware Engineering · on the way
- Model Checking and the State-Space ExplosionSoftware Engineering · on the way
- Hoare Logic and Proving a Program Meets Its SpecificationSoftware Engineering · on the way
- Type Soundness: Progress and PreservationComputer Systems · on the way
- Cryptographic Security Definitions and Proof by ReductionNetworks & Security · on the way
- Reproducibility: Seeds, Environments and the AblationSoftware Engineering · on the way
- Scoping and Writing a Thesis-Scale ProjectSoftware Engineering · on the way
- Interpretability: Probes, Features and CircuitsMachine Learning · on the way