What do we call matter?
Compare material properties with collective mass and identify the physical responses that a theory of matter must explain.
REALITY & TIME · EXISTENCE AND THE WORLD WE EXPERIENCE
Matter identity and structure
Explore matter identity and structure through questions connecting temporal order, change, experience, and the interpretation of reality.
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Particles and fields
Calculate four normal modes on a ring, distinguish mode discreteness from quantized excitation energy and connect particle descriptions to field dynamics.
The identity of an object through change
What makes a changing thing the same thing? Examine preserved quantities, causal histories, continuing renewal and retained information.
Mass and inertia
Use a two-cart comparison to connect inertial response, mass ratios and the physical tasks facing an emergent account of matter.
Energy as a physical quantity
Follow an ideal cart and spring, calculate an energy balance, and distinguish internal energy, system mass and the assumptions behind conservation.
Why matter holds together
Change the depth and energy of a Morse potential to inspect turning points, bounded motion and the threshold for separation.
Atoms as tests of a theory
Compare linked atomic intervals, eliminate a fitted scale and see how a second transition can test a model calibrated with the first.
Vacuum states and excitations
Compare a displaced vacuum with a one-quantum state of the same mean excitation energy, then distinguish their counting statistics.
Symmetry and particle descriptions
Use a two-state Hamiltonian to see what one symmetry permits, what a second symmetry forbids and which particle properties still need dynamics.
What makes particles identical?
Explore two-photon interference at a beam splitter and see how unobserved-state overlap changes coincidences while mean counts stay fixed.
How composite systems become wholes
Separate centre motion from internal deformation in a spring-connected pair and test when a composite behaves as a single object.
Matter as a persistent process
Compare a translating pulse with a diffusing pulse and identify which retained properties support a physical account of persistence.
Constants and the scales of matter
Connect atomic length, energy and time scales, then follow the consequences of changing one input while keeping units and assumptions explicit.
From a model to a material object
Distinguish frequency fitting, physical calibration and reserved predictions using an oscillator, then connect the method to a generative model of matter.