George Nicholas Hatsopoulos (January 7, 1927 – September 20, 2018) was a Greek American mechanical engineer noted for his work in thermodynamics and for having co-founded Thermo Electron.

[2] Matrad Corporation and MIT also provided financial support for his doctoral thesis The Thermo-Electron Engine.

Several years later, George asked his brother (John Hatsopoulos) to join the company as financial controller.

[8] Under George Hatsopoulos, Thermo Electron became a major provider of analytical instruments and services for a variety of domains.

[10] In 1996, Hatsopoulos won the John Fritz Medal, which is the highest American award in the engineering profession and presented each year for scientific or industrial achievement in any field of pure or applied science.