*The laws of classical thermodynamics, which are very apparent on the macroscopic scale, have been shown to also work on the quantum scale.*

Physicists have a long been working on establishing one common framework, a theory of everything, which should encompass all physical laws, including the Standard Model, Relativity, and Quantum Mechanics.

In this quest for big unification, different theories of physics are scanned from every angle in order to detect some new properties or learn how different properties would complement each other.

#### Read More: **11 Facts That Help Explain the Quantum Computer**

What about the laws of classical thermodynamics? Can they work on the quantum level? Can these laws that describe the behavior of matter with regard to heat and energy flow be applied at the atomic and subatomic level?

The laws of classical #thermodynamics can work on the #quantum scale.Click To TweetHere we enter the field of quantum thermodynamics, a relatively new field of research where scientists try to bring classical thermodynamic and quantum physics together.

## Quantum Thermodynamics: Extending Classical Thermodynamic Theorems to Quantum Physics

Although they coexisted for long as they were both being developed around the same time, quantum physics and **classical thermodynamics** are only now starting to overlap.

Sebastian Deffner is an Assistant Professor of Physics at the University of Maryland Baltimore County who focuses his research on **quantum thermodynamics**.

Deffner and Anthony Bartolotta, a graduate student of physics at Caltech, have investigated the **Jarzynski equality**, a classical stochastic thermodynamics principle in light of quantum field theories.

Their work provides further evidence that the laws and principles of classical thermodynamics seem to be as effective on the big scale as on the quantum level.

A fluctuation theorem, the Jarzynski equality is an equation in statistical mechanics that helps calculate the free energy difference of an object between two different states.

The two researchers have published a paper, “Jarzynski Equality for Driven Quantum Field Theories”, where they show how fluctuation theorems, mainly the Jarzynski equality, and the two-state vector formalism can find more validation into quantum field theories.

Professor Deffner explains:

“*Thermodynamics is a phenomenological theory to describe the average behavior of heat and work. Originally designed to improve big, stinky heat engines, it was not capable of describing small systems and systems that operate far from equilibrium. The Jarzynski equality dramatically broadened the scope of thermodynamics and laid the groundwork for stochastic thermodynamics, which is a new and very active branch of research.*”

Understanding how thermal fluctuations work in quantum systems may push research in several domains from giving scientists insights into the early formation of the universe to nanoscience applications.

For example, nanosystems are constantly in motion due to thermal fluctuations. As such, the study of the thermodynamic processes that govern these movements can help design more efficient nanodevices.