Today we’re going to talk about what life is like at the very centers of black holes — the singularity — and whether we’ll ever get to see any “naked singularities” out there in the cosmos. This week’s question comes to us from Scott Rehm who asks: The idea of a naked singularity seems bizarre to me. If the event horizon truly is just the “line of no return” and is simply there because of the very nature of singularities, how can you have a singularity without one? I’ve talked a fair amount about black holes in in previous columns and, of course, in my book. As io9 readers, you were almost certainly familiar with the basics before I came along: A black hole is a region of such strong gravitational pull that nothing can escape not even light. The point of no return, as you know, is referred to as the “Event Horizon” which is what Scott was talking about. To give you some idea of the scales involved, for a black hole the mass of the sun, the event horizon is at a radius of about 3 kilometers, and if you could somehow smash the earth down to a black hole, it would only have a radius of about 9 mm. (Note to belligerent super-intelligent aliens: Please don’t.) The takeaway from my article on falling into a black hole is that from your perspective as you fall in, crossing the event horizon pretty quickly, and for stellar mass black holes, you get killed very quickly — it takes about a tenth of a second between mild discomfort and being ripped to shreds by tidal forces. To someone far away, all of this seems to take literally forever.
As you probably know, one of the big goals –- arguably the big goal — of the LHC is to find the elusive Higgs Boson. The two biggest experiments in the Large Hadron Collider, ATLAS and CMS, announced their data updates yesterday. Both ATLAS and CMS have found a signal with relatively high significance suggesting that the Higgs Boson is real and that it has a mass of roughly 135 times the mass of a proton (or, to you experts, approximately 125 GeV). This is a big deal because 1) The Higgs Boson is the last undetected particle in the Standard Model of physics, and 2) The Higgs field is what gives other particles their mass.
So what happened before the big bang?
Not only don’t we know what happened before the Big Bang, we don’t even know what happened in the instant immediately following the Big Bang.
Our knowledge of physics in the first 10^-44 seconds after the beginning (which, admittedly, is a pretty damn short time) is virtually non-existent. This instant is known as the Planck Time, and since we don’t know what happened before the Planck time with anything even remotely resembling certainty, we absolutely don’t know what happened before the Big Bang. Regardless, logic dictates that we’re left with one of two possibilities:
* The universe had some sort of beginning, in which case we’re left with the very unsettling problem of what caused the universe in the first place.
* The universe has been around forever, in which case there’s literally an infinite amount of history, both before and after us.
Neither of these is satisfying. Take the Old Testament view, for instance. We’re to understand that God created the world. In that case our universe has a definite beginning. However, God himself is supposed to be eternal. What was he doing before he created our universe? It’s no more satisfying to assert that the universe has been here all along. Is there literally an infinite amount of history? That doesn’t make sense.
As a particularly clever cheat (or theory, if you prefer), in 1982 Alex Vilenkin of Tufts University showed how what we’ve learned from quantum mechanics might shed light on the how the universe popped into being.
What happened before the Universe? - Ask a physicist News, Videos, Reviews and Gossip
A mitten that violates the Second Law of Thermodynamics.
Catching up on some old web comics today.
Enjoy, guys. Enjoy.
(via Questionable Content: New comics every Monday through Friday)
The claim that neutrinos can travel faster than light has been given a knock by an independent experiment.
On 17 October, the Imaging Cosmic and Rare Underground Signals (ICARUS) collaboration submitted a paper to the preprint server arXiv.org, in which it offered a rebuttal of claims to have clocked subatomic particles called neutrinos traveling faster than the speed of light. The original results were published on 22 September by the Oscillation Project with Emulsion-Tracking Apparatus (OPERA) experiment. Both experiments are based at Gran Sasso National Laboratory near L’Aquila, Italy, and detect neutrinos coming in a beam from CERN, Europe’s high-energy particle physics laboratory near Geneva in Switzerland, about 730 kilometers away. Unlike OPERA, ICARUS does not measure the neutrinos’ speed directly. Instead, it has shown that the energy spectrum of the neutrinos does not exhibit an effect predicted last month by Andrew Cohen and Sheldon Glashow, theoretical physicists at Boston University in Massachusetts.
If the Cohen-Glashow effect is a valid prediction, “neutrinos are not superluminal,” says Sandro Centro, a physicist at the University of Padua in Italy, deputy spokesman for ICARUS and a co-author of the latest paper.
Cohen says that an energy spectrum provided by OPERA showed the same inconsistency, and that the spectrum from ICARUS has added to the problem. “There’s always value to having things checked independently,” says Cohen. “I think it’s great ICARUS has done this so quickly.”
Finding Puts Brakes on Faster-Than-Light Neutrinos: Scientific American
So there.
(And there’s a lot more if you follow the link.) (And thank you @thalidar for making me aware of that.)
Dark Matter Detector
Juan Collar, associate professor in physics at the University of Chicago, holds one of the early germanium detector prototypes similar to the one being used in the Coherent Germanium Neutrino Technology (CoGeNT) experiment, situated nearly half a mile deep in the Soudan Mine in Minnesota. Such underground locations help screen out false dark-matter signals from other natural sources of radiation. Detectors of this kind are used because of their sensitivity to weak levels of radiation.
(via Possible Sighting of Dark Matter Lights Up Physics Community | Popular Science)
When the Euclid mission lifts off at the end of this decade, it will map galaxy clusters in infrared and visible light, helping to blueprint the large-scale structure of the universe. And a bunch of amateur science geeks who signed up for the competition will use their specialized skills to elucidate those findings.
(via How a Team of Enthusiasts Are Mapping Dark Matter | Popular Science)
}
