QFT at Finite Temperature

Why is it interesting?

While nowadays we can use as a good approximation that the temperature is zero, in the early universe it was significantly higher. Thus, if we want to understand the fundamental interactions in the early universe, i.e. shortly after the Big Bang, we need to take into account that the temperature is non-zero.

Layman

Explanations in this section should contain no formulas, but instead colloquial things like you would hear them during a coffee break or at a cocktail party.

Student

Good introductions are

quantum_field_theory_for_children.pdf and
Thermodynamics of electroweak matter by A. Gynther

Standard References:

Finite Temperature Field Theory and Phase Transitions by Mariano Quiros
Finite-Temperature Field Theory by Joseph I. Kapusta

Researcher

The motto in this section is: the higher the level of abstraction, the better.

Common Question 1

Common Question 2

Examples

Example1

Example2: