What happens when quantum mechanics and relativity meet?
Experiment put atoms in a superposition of trajectories to find out.
Experiment put atoms in a superposition of trajectories to find out.
The short version
- Almost a hundred years ago, physicists theorized out what free fall should do to a quantum wave.
- If the solution they came up with is wrong, quantum mechanics and Einstein’s theory of gravity flatly contradict each other.
- But testing it has been impossible because nobody has managed to build an interferometer that could perform the necessary measurement.
What happened
Now, a team led by Ron Folman, a physicist at Ben-Gurion University of the Negev, with collaborators in Germany, the UK, and the US, including Nobel laureate Roger Penrose, has done it. They built a new interferometer that gives a single atom two possible paths at once: one that involves a free fall, and another where it is held perfectly still.
Why it matters
Both paths end at the same place at the same moment, allowing the team to measure what the fall does to a wave-like property of the atom.
Summary by Nerd News Network. Read the full article at Ars Technica via the links above and below.