Can quantum systems become more disordered, as thermodynamics would predict? Yes, they can - if a proper definition of "entropy" is used. It is one of the most important laws of nature that we know: ...

Almost exactly 200 years ago, French physicist Sadi Carnot determined the maximum efficiency of heat engines. The Carnot ...

For more than a century, thermodynamics has described how heat flows and engines run, while quantum mechanics has ruled the ...

According to all the known laws of physics, the Big Bang should have created a Universe consisting of both matter and ...

In the strange, often unintuitive world of quantum physics, one mystery has stood out for decades: Can quantum entanglement be manipulated in a reversible way, like energy in a perfect heat engine?

Schematic of a single photon with zero angular momentum (green) splitting into two photons (red) with either zero or opposite angular momenta (sketched through the spatially varying color), which adds ...

Physicists have long sensed that the usual picture of events unfolding as a sequence of causes and effects doesn’t capture the fundamental nature of things. They say this causal perspective probably ...

We’re celebrating 180 years of Scientific American. Explore our legacy of discovery and look ahead to the future. This year is the International Year of Quantum Science and Technology, according to ...

It took 125 years, but in 2025 a team of mathematicians discovered the solution to a long-puzzling problem about the ...

Quantum technologies could transform society—but their national and economic security implications also bring complex legal hurdles. To help innovators navigate those challenges, the Chicago Quantum ...