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'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.
The important thing about being 'observed' is if it has an effect on something else - such as the photons from the laser used to record it.
What is most certainly does NOT mean is that it does anything because a human consciousness is watching the process. A robot or mote of dust could have been 'observing' it (and in effect WAS), and the same effect would happen.
That's what I strongly dislike about the terminology around 'observer' effects. It makes people evoke touchy-feely human awareness stuff, when it's really just referencing microscale interaction events. What matters is that if events occur which COULD matter outside the system, like photons bouncing against the atom, then that's an 'ovservable' event in the context.
In the microscopic landscape of these experiments, we're a distant afterthought - a bacterium would be almost too big to sensibly consider - and trillions of bacteria would barely be observable to us. In other words, it's really not about US, to any sensible interpretation. Psuedoscience is all about us - keep that in mind when you see the sales pitches, as they'll be using the bad interpretation all the time they can.
Ryan Fenton
Put another way, imagine the universe is a simulation. The programmer didn't want to waste CPU cycles simulating every single atomic particle, so when no meaningful atomic-scale interactions are occurring, the simulation uses a simpler statistical model instead.
When the laser light is striking the atoms in the lattice, the interactions between the light and lattice force the simulation to model every individual atom and photon. So each them are modeled precisely, and no tunneling occurs.
When the laser light is not striking the atoms in the lattice, there's no need to model every (non-)interaction and the simulation reverts to a statistical model. When the laser is turned on again you can locate the position of every atom again. Since the original lattice arrangement was not "saved", the simulation has to generate a new arrangement of atoms in the lattice. This new arrangement is statistically identical to the original, but little details like the positions of individual atoms are not identical. The misplaced atoms appear to have "moved", and we call those movements "tunneling".
Have fun sleeping tonight. -- The Matrix
How would they know what the atoms do without observing them?
Check back later, and see how many tunneled while they weren't looking. If they tunneled, they will be in a different location.
If they find there was tunneling while they weren't looking, that is pretty strong evidence that we are living inside a simulation. The universe behaves differently if we are not looking, so that God can save computing resources. There is no point in calculating details that no one will see. Just like the way OpenGL can skip the shading of hidden polygons.
Not really. It just means reality doesn't conform to your classical notion of particles and 3D space-time. Why that is, no one really knows. But, the math works -- quantum mechanics, I mean. Essentially, nothing at the subatomic particle scale has a defined size or specific position in three dimensions. Things only appear to interact at specific locations. The more interactions at one location, the less likely a quanta or "particle" is to interact somewhere else. This is the basis of the particle/wave duality. If you're looking, observing, interacting, measuring, etc... things interact at a defined location and act like classical particles. If you let the system be and check its final interactions with surrounding objects, you pick up a wave-like probability function and/or pattern of interactions.
If your "we don't render that because you don't see it" assumption were true, then we would not see particle/wave duality. With a 2 slit experiment, we get an interference pattern when not looking, but 2 lines when we do look. It's actually more work to compute the interference pattern than to compute 2 lines. That wouldn't make any sense if the goal is to conserve computing power. There are multiple instances of this. Waves and their interactions are inherently more computationally intensive than simple particle interactions.