Peter Higgs is going to have to wait at least one more year (although he might be used to waiting by now, since it took researchers almost half a century to find his boson in the first place). The 2012 Nobel Prize in physics is going to Serge Haroche and David Wineland for their work on observing the quantum state of individual atoms. For my fellow Americans who like to keep track of US Nobel winners as a quantifiable metric of our awesomeness at science, not only is Dr. Wineland an American, he works for us taxpayers as an employee of NIST. Lest you think that tax dollars should not be frittered on basic science, consider some of the important applications to come from government research, as in: “The next time a GPS keeps you from getting lost, thank a fed” Now, this current research promises to point the way towards the next generation of quantum computers and optical clocks. More importantly, this work helps us make sense of how, as far as well can tell, the Universe actually works. Far from being a weird curiosity, the paradoxes of quantum mechanics are how things really behave when you peel back all the layers. It’s our everyday experience, where things aren’t (or a least seem to act like they are not) in multiple places at once, that needs explaining.
A big difficulty in obtaining that explanation is that small things (like electrons) and big things (like cats) just don’t seem to play by the same rules. And what’s more, there doesn’t appear to be a clear line between what is a “small thing” and what is a “big thing.” I guess we are now so used to the idea that electrons in atoms exist not in well defined locations, like planets orbiting the sun, but rather in spread-out “orbitals,” that it doesn’t phase us (much) anymore. But some (OK, basically everyone) are still uncomfortable with the idea of large objects finding themselves in a superposition of states. But if electrons can be in two places at once, and ions are affected by the position of the electron, AND no interaction with the outside world ruins the quantum weirdness because of “decoherence” (whatever that is), it should be possible to transfer the “two-places-at-once-ness” from the electron to the ion. And that is what one of the Nobel-worthy experiments did. An individual ion was placed in a trap so that it could vibrate at different amplitudes. The ion also had an electron orbiting around it that could be put into various excited states (orbitals). Using pulses of laser light, the scientists were able to prepare the electron in a superposition of two different orbitals at the same time. They then used another pulse to to change the vibrational state of the ion, but this pulse only works on the ion if the electron was one of the states, but not the other. The end result is an ion is left in a superposition of vibrational states (it’s like the ion telling itself “if the electron was there, now I should be here… but if the electron was over here, I need to be here…) Since these vibrations represent different positions for the ion, it really is in more that one place at once. This superposition could then be transferred to a second ion that was also in the trap and felt the influence of the spread out first ion. While we still can’t give a complete explanation of how the cray rules of quantum mechanics gives rise to the Newtonian physics that we observe at home, research like this help fill in the gaps and gets us closer to a unified description of reality.