The Science Thread

The Brian Cox one explains what's going on.

40 years experience as a bacterial geneticist have taught me that bacteria possess many cognitive, computational and evolutionary capabilities unimaginable in the first six decades of the 20th Century...

The conventional wisdom is an extension of the mechanistic views that came to dominate biological thought in the early years of the 20th Century. The idea is that microbes, particularly prokaryotes, exemplify the basic properties of living cells reduced to their simplest configurations ... .Molecular biology came into being on the promise of confirming mechanistic views of life by defining how living cells worked at a physico-chemical level...

My own view is that we are witnessing a major paradigm shift in the life sciences in the sense that Kuhn (1962) described that process. Matter, the focus of classical molecular biology, is giving way to information as the essential feature used to understand how living systems work. Informatics rather than mechanics is now the key to explaining cell biology and cell activities. Bacteria are full participants in this paradigm shift...

It seems that video presentations are the preferred form of information exchange in this thread, so this may not count.

It seems that video presentations are the preferred form of information exchange in this thread . . .

Interesting, funny, or amazing science information. I'll start. These guys don't go deep, but make it interesting.

[youtube]https://www.youtube.com/watch?v=ckSoDW2-wrc[/youtube]

No one, for that matter, wants to see your 15 minute video.

Tevatron Reveals Higgs Boson Properties—4 Years After Shutting Down

The Tevatron collider—the world’s second most powerful particle accelerator—was shut down in 2011. Now, from beyond the grave, it’s revealing properties of the Higgs boson.

The American accelerator, situated at Fermilab in Batavia, Illinois, ran from 1983 until 2011. During that time, it showed teasing glimpses of the Higgs, but ultimately it was the Large Hadron Collider that finally found the elusive particle. The discovery primarily identified the particle’s mass as 125 giga-electron volts—about 133 times the mass of the proton.

But like any particle, the Higgs boson has other properties, too, such as quantized amount of angular momentum (referred to by physicists as spin) and a kind of symmetry known as parity (which can be either even or odd), which dictate how it decays into different particles. The Standard Model predicts that the Higgs should have zero spin and positive parity—but experimental results were required to confirm that’s the case.

Results from the LHC already suggest that to be the case, but analysis of data from Tevatron soon to be published in Physical Review Letters helps confirm the spin-parity of the Higgs. Science explains how researchers from Fermilab went about it:

Instead of studying the decays of the Higgses, they looked for signs of a Higgs produced in tandem with a Z boson or a W boson, particles that convey the weak nuclear force.... (The Higgs was assumed to decay into a pair of particles known as a bottom quark and an antibottom quark.) From the energies and momenta of the Higgs and its partner, researchers then calculated a quantity called the invariant mass for the pair. Were the Higgs and the partner born from the decay of a single parent particle, this quantity would be the mass of that parent. In actuality, the Higgs and its partner would emerge directly from the chaos of the particle collision, so the parent particle is purely hypothetical.

Nevertheless, by calculating the mass of that hypothetical parent particle, researchers were able to test for different combinations of spin and parity by proxy. If the Higgs had “exotic” spin-parity rather than the standard model characteristics, the observed invariant mass would be higher. So researchers working with the two particle detectors fed by the Tevatron—CDF and D0—searched for such high-invariant mass pairs. Finding none, they ruled out even more stringently exotic versions of the Higgs. So even though Tevatron physicists never conclusively observed the Higgs boson, they were able to put limits on its properties.

The new results from Tevatron confirm with more certainty than those from the LHC that the Higgs has zero spin and positive parity—though, arguably, the LHC did get there first. That’s understandable, though, as many people working on Tevatron shifted to the LHC to perform new experimental work rather than analysing old data.

Regardless of firsts, it’s probably the last exciting glimpse of the Higgs that Tevatron will see. With the baton now firmly passed on to the LHC, our further understanding of the Higgs will come from Europe, not the U.S.. [arXiv via Science]