Skip to main content

PX423 - Kinetic Theory

  • Module code: PX423
  • Module name: Kinetic Theory
  • Department: Physics
  • Credit: 7.5

Content and teaching | Assessment | Availability

Module content and teaching

Principal aims

To introduce Maths/Physics students to non-equilibrium statistical physics and to give them an appreciation of mathematical physics as separate sub-discipline

Principal learning outcomes

At the end of the module you should: Be able to discuss the derivation and solution of the Boltzmann equation as it applies to simple problems and use it to derive the Maxwell distribution; Be able to set up and solve simple boundary value problems to describe neutron flux in a diffusion approximation; Understand the significance of the Fokker-Plank approximation and apply it to the diffusion of heavy particle in a light gas

Timetabled teaching activities

15 lectures

Departmental link

Other essential notes

'Kinetic Theory' is the theory of how distributions change. The description of such phenomena is statistical and is based on Boltzmann's equation (the same Boltzmann who sorted out the equilibrium statistical mechanics you met in Thermal Physics II) and on the related Fokker-Planck equation. These study the evolution in time of a distribution function, which gives the density of particles in the system's phase space. (Phase space is the space of states of the system, which means specifying particles' position and momenta.) The module establishes relations between conductivity, diffusion constants and viscosity in gases. It looks at molecular simulation and applications to financial modelling (many of the concepts are also the basis for models of the 'motion' of stock and option prices in financial markets). An additional motivation of this module is to illustrate how some of the mathematics you learnt in second year applied mathematics modules is used in theoretical physics.

Module assessment

Assessment group Assessment name Percentage
7.5 CATS (Module code: PX423-7.5)
B (Examination only) 1.5 hour examination (Summer) 100%

Module availability

This module is available on the following courses:

  • Undergraduate Mathematics and Physics (BSc MMathPhys) (FG33) - Year 3
Optional Core


  • Undergraduate Mathematics (BSc) (G100) - Year 3
  • Undergraduate Mathematics with Intercalated Year (G101) - Year 4
  • Undergraduate Mathematics (MMath) (G103) - Year 3
  • Undergraduate Mathematics (MMath) (G103) - Year 4
  • Undergraduate Master of Mathematics (with Intercalated Year) (G105) - Year 3
  • Undergraduate Master of Mathematics (with Intercalated Year) (G105) - Year 4
  • Undergraduate Master of Mathematics (with Intercalated Year) (G105) - Year 5
  • Undergraduate Mathematics (MMath) with Study in Europe (G106) - Year 4
  • Undergraduate Mathematics and Physics (BSc) (GF13) - Year 3
  • Undergraduate Mathematics and Physics (with Intercalated Year) (GF14) - Year 4