Strengthening the second law of thermodynamics

According to the second law of thermodynamics, the total entropy of a closed process can increase or stay the same, but never decrease. The second law guarantees, for example, that an egg can wobble off a table and leave ...

Is the past (and future) there when nobody looks?

In 1961, the Nobel prize winning theoretical physicist Eugene Wigner proposed what is now known as the 'Wigner's friend' thought experiment as an extension of the notorious Schroedinger's cat experiment. In the latter, a ...

Solving 'barren plateaus' is the key to quantum machine learning

Many machine learning algorithms on quantum computers suffer from the dreaded "barren plateau" of unsolvability, where they run into dead ends on optimization problems. This challenge had been relatively unstudied—until ...

Healing an Achilles' heel of quantum entanglement

Louisiana State University Associate Professor of Physics Mark M. Wilde and his collaborator have solved a 20-year-old problem in quantum information theory on how to calculate entanglement cost—a way to measure entanglement—in ...

page 5 from 13