Slashdot Mirror
'Zeno Effect' Verified: Atoms Won't Move While You Watch (cornell.edu)
An anonymous reader writes: One of the oddest predictions of quantum theory – that a system can't change while you're watching it – has been confirmed in an experiment by Cornell physicists. Graduate students Yogesh Patil and Srivatsan Chakram created and cooled a gas of about a billion Rubidium atoms inside a vacuum chamber and suspended the mass between laser beams (abstract).
In that state the atoms arrange in an orderly lattice just as they would in a crystalline solid. But at such low temperatures the atoms can "tunnel" from place to place in the lattice. The famous Heisenberg uncertainty principle says that position and velocity of a particle are related and cannot be simultaneously measured precisely.
The researchers observed the atoms under a microscope by illuminating them with a separate imaging laser. A light microscope can't see individual atoms, but the imaging laser causes them to fluoresce, and the microscope captured the flashes of light. When the imaging laser was off, or turned on only dimly, the atoms tunneled freely. But as the imaging beam was made brighter and measurements made more frequently, the tunneling reduced dramatically.
In that state the atoms arrange in an orderly lattice just as they would in a crystalline solid. But at such low temperatures the atoms can "tunnel" from place to place in the lattice. The famous Heisenberg uncertainty principle says that position and velocity of a particle are related and cannot be simultaneously measured precisely.
The researchers observed the atoms under a microscope by illuminating them with a separate imaging laser. A light microscope can't see individual atoms, but the imaging laser causes them to fluoresce, and the microscope captured the flashes of light. When the imaging laser was off, or turned on only dimly, the atoms tunneled freely. But as the imaging beam was made brighter and measurements made more frequently, the tunneling reduced dramatically.
What is most certainly does NOT mean is that it does anything because a human consciousness is watching the process.
That's still an open question.
Required reading for internet skeptics
Observing at small scales is not a passive activity. You have to inject energy into the system to make an observation. That injection of energy alters the system. So the universe does know when you are actively looking at it. Think of looking as not just looking with eyes passively but also shining a high energy flashlight in the direction of looking.