IPhO modern physics
Special relativity tools, quantum reasoning and nuclear fundamentals for olympiad-style questions.
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Before you begin
Modern physics problems ask you to choose what remains fixed when the description changes: the same pair of events in different frames, the same energy zero across a quantum boundary, or the complete energy and momentum of a reaction. Start by identifying the system, the measured quantity and the model’s limits before calculating.
Be comfortable with: special relativity at H3, A-Level quantum physics and nuclear physics, and the IPhO problem-solving framework.
Learning goals
- Apply modern physics models and problem-solving methods in competition settings.
Lessons
Work through them in order.
Build the bridge
Build the official core
Transfer to unfamiliar problems
Practise and check
Topic reference
What you should be able to do
- Select a frame or invariant in relativity and verify the non-relativistic limit where appropriate.
- Estimate the controlling quantum length and energy scales before choosing a detailed model.
- Apply conservation laws and quantisation ideas to atomic and nuclear processes with consistent units and signs.
Official scope: Stages selected official relativity, quantum, atomic and nuclear content while keeping specialised calculation techniques in later lessons.
Training habits
- Distinguish a coordinate measurement from a clock path, a level energy from a transition energy, and a detector count rate from decay activity.
- Estimate the controlling scales, then test whether the non-relativistic, one-electron, deep-well or negligible-recoil approximation applies.
- Attempt the changed-constraint questions before opening their answers. Numerical feedback checks its stated quantities; compare derivations and model decisions with the public solutions yourself.