In the late 1970s, legendary physicist John Wheeler proposed a radical question: Exactly when does the universe notice that we're paying attention to a quantum experiment? And does it really matter?

Does the universe notice that we're paying attention to a quantum experiment? The answer goes against everything we thought we knew. When you purchase through links on our site, we may earn an ...

Using a precisely aligned pair of laser beams, scientists can now hold a single aerosol particle in place and monitor how it charges up. The particle’s glow signals each step in its changing ...