Glossary Boltzmann Constant

# Boltzmann Constant

First of all, there are constants named after Ludwig Boltzmann, first Boltzmann constant and the second Stefan-Boltzmann constant. We will discuss the first one here.

Both Boltzmann constants play vital roles in Physics and Astronomy.

## Role of Boltzmann Constant in Physics

Boltzmann Constant unites the macroscopic and microscopic worlds, and provides the basis for the zeroth law of thermodynamics.

## Zeroth Law of Thermodynamics

If you could ‘look inside’ an isolated system (in equilibrium), the proportion of constituents in the system with energy E is a function of E, and the Boltzmann constant (k or kB).

• The proportion of constituents in the system with energy E is proportional to e-E/kT.
• Here T is the temperature in Kelvin.
• k is Boltzmann’s constant and k=1.38×10-23 Joules per Kelvin.

Who was Ludwig Boltzmann?

Ludwig Eduard Boltzmann was an Austrian physicist and philosopher.

What is the value of Boltzmann Constant?

The value of Boltzmann Constant k is 1.38×10-23 Joules per Kelvin.