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Jay Cross
18,237 followers -
One of a long line of Renaissance Men
One of a long line of Renaissance Men

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Cosmic Muonic Neutrinos

There is an excess of Muonic Neutrinos above 177 TeV, perhaps beyond 3 PeV, detected by IceCube. The detection is near certain, the sources are unknown, but not isolated to a few directions in the sky. The paper linked here discusses the detection and computations needed to reveal this result. Maybe it is something new and interesting, or maybe it is only the spray of millions of quasars. The search begins now.



I'm a new owner to an old community.
Someone got banned by accident, and we can't figure out how to unban him.
I've looked at some posts here on the topic, but don't see a Hamburger icon or membership list anywhere.

If there is a helpful page of instructions and screenshots on how to do this could you please point me to it?

Thanks in advance


My 9th Cousin Mary Pickford (Silent Film Star) and I both descend from John Proctor who died suddenly in Salem MA, in 1692.


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Inspirational quotes by Dr. Martin Luther King Jr. spoken over a bed of Mixed MetaFour singing U2's song "MLK" (Let it Rain). 2:15 minutes of understanding why we have a national holiday named after this man.

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This has been an interesting mystery. Nice to take a big step toward resolving it... including now a suggestion that there are at least two classes of progenitors for these FRBs.
Fantastic! Scientists are for the first time able to find the source of a Fast Radio Burst:  The signal came from a galaxy located about 6 billions light years away!

New fast radio burst discovery finds 'missing matter' in the universe

"The team then used the National Astronomical Observatory of Japan (NAOJ)'s 8.2-m Subaru optical telescope in Hawaii to look at where the signal came from, and identified an elliptical galaxy some 6 billion light years away. "It's the first time we've been able to identify the host galaxy of an FRB" added Dr Keane."

"An international team of scientists using a combination of radio and optical telescopes has for the first time managed to identify the location of a fast radio burst, allowing them to confirm the current cosmological model of the distribution of matter in the universe.

On April 18, 2015, a fast radio burst (FRB) was detected by the Commonwealth Scientific and Industrial Research Organisation (CSIRO)'s 64-m Parkes radio telescope in Australia. An international alert was triggered to follow it up with other telescopes and within a few hours, a number of telescopes around the world were looking for the signal, including CSIRO's Australian Telescope Compact Array (ATCA).

FRBs are mysterious bright radio flashes generally lasting only a few milliseconds. Their origin is still unknown, with a long list of potential phenomena associated with them. FRBs are very difficult to detect; before this discovery only 16 had been detected."

More of Fast Radio Bursts (FRB): https://en.wikipedia.org/wiki/Fast_radio_burst

Read more at: http://phys.org/news/2016-02-fast-radio-discovery-universe.html
The study: http://www.nature.com/nature/journal/v530/n7591/full/nature17140.html

Image: This image shows the field of view of the Parkes radio telescope on the left. On the right are successive zoom-ins in on the area where the signal came from (cyan circular region). The image at the bottom right shows the Subaru image of the FRB galaxy, with the superimposed elliptical regions showing the location of the fading 6-day afterglow seen with ATCA. Image Credit: D. Kaplan (UWM), E. F. Keane (SKAO).

#space   #frb   #fastradiobursts   #universe   #matter  
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Brian Koberlain hits it again... one other thing about this observation worthy of note is that until now, we had not proven unambiguously that the speed of gravity is the speed of light. ... if this pattern repeats for future gravitational wave observations, then it has been demonstrated.

Another thing of mild note is that the 0.4 second delay of the gamma rays could potentially be related to the possible increase in path-length for the highest energy photons that is predicted IF certain quantum foam models are correct. More modeling of the situation would be required to make a stronger statement about this.

If this GRB was caused by merging black holes, it would be quite surprising. Stellar mass black hole binaries aren’t expected to have a disk of material around them that could emit gamma rays.

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The announcement will be tomorrow morning (Eastern Time), and this paper is not that announcement, but it does tell us a little bit about what we should expect to see, what it means, and most importantly to me, it tells why the rumored black hole masses were so large.

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Upcoming Strong Gravity Observations

There are a few things coming up (hopefully) within a year or so that are new observations about places with very strong gravity. One of these is the Event Horizon Telescope, which should soon be able to start imaging the central massive black hole in the Milky Way. This paper: http://arxiv.org/pdf/1601.06799.pdf talks about simulations of what we might be able to see, and how fast-changing events near the event horizon could disrupt the results.

The other observations will be from AdvancedLIGO, and there are plenty of papers about that recently. They are hoping to observe merging stellar-mass black holes and neutron stars.

In both cases they have the potential to start confirming or eliminating various alternatives to relativity which people have been considering for almost a century, as well as potentially start taking us another step closer to getting some concrete clues about what might be String Theory. This could be a very exciting time for theoretical physicists.

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Ellis & Silk wrote “Faced with difficulties in applying fundamental theories to the observed Universe,” they wrote, some scientists argue that “if a theory is sufficiently elegant and explanatory, it need not be tested experimentally”. --- which is unfortunately a very weak position.

String Theory shows that Karl Popper's Falsifiability demand for science has a boundary issue. String Theory cannot yet be falsified, but one of the goals of String Theorists is to get it to a point where it can be. Does that mean that all the math and experiments and theoretical work going into it now are not science, but will retroactively become science only when they get to that goal?

Perhaps the problem is a nuance where exploring an idea is doing science, but something isn't a known science until it can be used to make a prediction of a phenomenon which later gets observed. It is inaccurate and insulting to say that people working on String Theory are not scientists.

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I'm hoping that some standards of operation are put in place. For example, I think it would be very bad to just let dust and debris fly away from these low-gravity objects.... maybe demanding that all asteroid mining should be done in tunnels with a thick Kevlar tarp covering the opening would be smart.
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