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The Pioneer Anomaly & Other Breaking Physics News
David Harris, editor-in-chief at Symmetrymagazine.org (a joint publication of Fermilab and SLAC), sends us to his blog covering the American Physical Society meeting now going on in St. Louis. Among the breaking physics news relating to topics we have discussed in the past: results that explain about 1/3 of the Pioneer anomaly by differential heat flow in the spacecraft; an analysis of the Fermilab Tevatron's chances of spotting the Higgs "God particle"; and a hint that an Italian team has replicated their results from the year 2000 pointing to a detection of dark matter.
The article states that Fermilab can begin exploring to 160GeV in the summer. LHC is due to be switched on before that. From all I've read, LHC has a MUCH better chance of being sure of what it finds at around those energies. I think any article on this subject can't even pretend to be balanced without discussing LHC.
todo - The developer's equivalent of confession: "Forgive me Father, for I have sinned..."
I think it was Leon Lederman who coined it in his book. He is definitely a high-energy physicist, he was director of Fermilab for years and won a Nobel Prize for discovering the bottom quark. I agree with the sentiment, though, if I never heard it again it would be fine with me. I read the book some years ago but can't remember why he called it that.
...wearing a skin-tight topless leather jumpsuit, with cutaway buttocks and transparent crotch panel.
Sadly, 10% of Fermi's staff is being laid off, and the rest must take a mandatory week off of unpaid leave every two months due to the funding SNAFU at the DOE.
"To those who are overly cautious, everything is impossible. "
Well, let's be fair. the Pioneer anomoly is just that, anomalous. We don't see the impact in other situations, we don't have a good explanation for it and it isn't very large. It is entirely possible that this could be the same sort of anomaly as the orbit of Mercury or the Michelsonâ"Morley experiment. It's possible, but it is also possible that it falls into the category of experimental error.
Please understand that the pioneer anomaly isn't treated in the same way as we remember (historically) anomalous results. No one disowned the researchers or completely dismissed their research. BUUUUTTTT...most of the explanations result in changes to the underlying framework of gravity (or alternatively, EM radiation) that don't really make sense. As far as we can tell it is better explained as an anomaly.
Hopefully we are wrong and we discover something really awesome out there!
The quarks are supposed to be named in pairs thusly:
Up down
Strange Charm
Truth Beauty
But somewhere in the 70's some particle group with little sense of wonder renamed Truth and Beauty to Top and Bottom, thus leaving Strange and Charm as sounding anachronistic.
The Higgs field and dark energy are about the closest things directly comparable to the aether in modern physics. Dark matter is very different: it clumps, so it isn't everywhere.
Oh. Well that is an interesting problem. Keep in mind that the oort cloud isn't really as dense as we might think it would be. If we assume only regular matter (no dark matter), then the density of the oort cloud is fantastically low. It is higher than the density of space between the earth and Mars only because there isn't the tidal and graviational forces of a Jupiter like body to pull stuff out of it.
:)
Then, from a gravitational standpoint, we are looking at VERY small curvature imposed by the comets and such floating around. Moreover, it is probably not something that translates well into some net field. We can abstract it, think of the oort cloud as a uniform density object, but that abstraction doesn't hold well to the truth.
If we WERE to abstract it, the well created by the oort cloud might just overcome that created by the sun at distances far away from the sun. But remember, that is a spherical cow evenly distributed with milk (har, har). The reason the oort cloud exists is because the comets and dust caught up in it are orbiting the sun. So we would have to imagine that the point where that influence wanes is very close to the edge of what we might call the oort cloud.
Even IF that is the case, we would see the impact of such a well (again, keeping with our assuption of a uniformally distributed Oort cloud) on light coming into the solar system from outside it. Much like seeing like passing a star (gets 'lensed') is sort of like seeing light emanating from that star seeing light from outside the solar system would be like seeing light from inside the oort cloud. We would have been able to find this anomaly by looking at any infra-solar source than comparing it to light from outside the solar system.
In the case of pioneer, we need to explain a slight red shift growing larger as pioneer gets further from earth. a red shift seen on BOTH probes but not from (as far as we can tell) any source other than those two probes. It's a pickle.
Of course, I'm not an expert on this, so I'm prepared to be wrong.