# The smallest possible thermal machines and the foundations of thermodynamics

- Institution: CERN
- Department: CERN Colloquium
- Speaker: Sandu Popescu
- Year: 2018
- Language: English
- Subjects: Physics
- Source: [CERN](https://videos.cern.ch/record/3010872)
- Licence: [CERN](http://copyright.web.cern.ch)
- Who can watch: Tweens profiles and older (sources give no ratings; placed by Invisible Network from the source's own words)

In my talk I raise the question on the fundamental limits to the size of thermal machines – refrigerators, heat pumps and work producing engines - and I will present the smallest possible ones. I will then discuss the issue of a possible complementarity between size and efficiency and show that even the smallest machines could be maximally efficient and I will also present a new point of view over what is work and what do thermal machines actually do. Finally I will present a completely new approach to the foundations of thermodynamics that follows from these results. .

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## Lectures

1. [The smallest possible thermal machines and the foundations of thermodynamics](https://invisiblenetwork.ai/learn/cern/3010872/413ad4e058e8), 1 h 18 min (CERN's player)