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Astronomers Strike Gravitational Gold In Colliding Neutron Stars (npr.org)
For the first time, scientists have caught two neutron stars in the act of colliding, revealing that these strange smash-ups are the source of heavy elements such as gold and platinum. From a report: The discovery, announced today at a news conference and in scientific reports written by some 3,500 researchers, solves a long-standing mystery about the origin of these heavy elements -- which are found in everything from wedding rings to cellphones to nuclear weapons. It's also a dramatic demonstration of how astrophysics is being transformed by humanity's newfound ability to detect gravitational waves, ripples in the fabric of space-time that are created when massive objects spin around each other and finally collide. "It's so beautiful. It's so beautiful it makes me want to cry. It's the fulfillment of dozens, hundreds, thousands of people's efforts, but it's also the fulfillment of an idea suddenly becoming real," says Peter Saulson of Syracuse University, who has spent more than three decades working on the detection of gravitational waves. Albert Einstein predicted the existence of these ripples more than a century ago, but scientists didn't manage to detect them until 2015. Until now, they'd made only four such detections, and each time the distortions in space-time were caused by the collision of two black holes. That bizarre phenomenon, however, can't normally be seen by telescopes that look for light. Neutron stars, by contrast, spew out visible cosmic fireworks when they come together. These incredibly dense stars are as small as cities like New York and yet have more mass than our sun. Further reading: 'A New Rosetta Stone for Astronomy' (The Atlantic), and Gravitational Wave Astronomers Hit Mother Lode (Scientific American).
"Chance favors the prepared mind."
This is an example of that at it's purest, the culmination of years of effort by hundreds of people, all for a moment that might not have happened in their lifetimes.
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I can't seem to find the result of the collision in any of the articles. Did they merge to form a black hole or a larger neutron star?
I love reading net kooks. So fundamentally ignorant, and yet so absolutely certain of their genius.
The world's burning. Moped Jesus spotted on I50. Details at 11.
LOL. Every scientific announcement uses that exactly that kind of wording. BTW, here's the press release in question:https://www.eso.org/public/announcements/ann17075/
You're right that if Einstein hadn't come up with it, special relativity could have been derived from the mathematical insights provided by Hendrik Lorentz and Henri Poincaré, but they hadn't yet quite put it all together into the single elegant package Einstein did.
You're off target about pretty much everything else, though. The Michelson-Morley experiment was only the first of many, many experiments that validate special relativity-- with today's measurement technologies that can measure the speed of light directly, there is no need to go to all the trouble Michelson and Morley did to do interferometry. There isn't any way to incorporate ether into today's extensive array of experimental results other than "luminiferous ether, if it exists, is completely unobservable."
Most optical gyroscopes use fibers these days, and don't deal with the speed of light in vacuum at all, although you can do it with ring laser gyroscopes... which obey special relativity.
http://www.geoffreylandis.com
I learned quite a bit about nucleosynthesis, but haven't revisited it in decades.
There are three main processes for synthesizing heavy elements. In the s-process (slow), neutrons are absorbed by heavy nuclei slowly enough that the nucleus has time to beta decay, if it is too neutron rich to be stable. The s-process happens in red giant stars, and the products can be released by stellar winds and planetary nebula formation.
In the r-process (rapid), neutrons are added very quickly to heavy nuclei, which absorb as many neutrons as they can and then, once the neutron bombardment ceases, beta decay back to stability. I don't recall whether we knew where the r-process happened when I was studying this, but this result would be r-process.
In the p-process (proton), nuclei grow by having protons added one at a time. This is presumed to happen in supernovae, and p-process nuclei are rare.
Isotopes coming from the s process will have abundances inversely proportional to their neutron cross section, because that cross section determines how quickly they move on. Also, while many isotopes can be produced by several of these processes, some can only be produced by one. My understanding is that these methods indicate that the s process is the predominant source of heavy elements. However this table (pointed out by other /. posters) contradicts my understanding, so possibly my knowledge has become outdated.
Can someone with more recent knowledge comment on how these new results can be reconciled with isotope abundances?
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
Did you just Google all this shit an Wikipedia and jot down your failed interpretation?
No, actually I did it the hard way, by earning a Ph.D. in physics.
It's not that what you are saying is wrong, it's more that you mix together correct statements with dubious statements, ignore most of modern physics experimental results, and then go on to make unorthodox and mostly-unsupported assertions. The point you should take away is that critiquing the 130-year-old Michelson-Morley experiments is mostly irrelevant; there are much better and much more recent experimental confirmations of special relativity. Yes, it is possible to come up with ether theories that also fit the same date, but in doing so the net result is that the theory ends up saying that the ether is undetectable, and the mathematical formulation is identical to special relativity.
http://www.geoffreylandis.com