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Jay Cross
Works at Oracle Corporation
Attended Rensselaer Polytechnic Institute
Lived in Berlin, MA
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Jay Cross

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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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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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Mine bad. Ligo
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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.
String theory is at the heart of a debate over the integrity of the scientific method itself.
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Not all hypothesis (or other useful tools) are scientific theories.
Is Math not a science because of  axioms?
Are they not useful?
Not all hypothesis are well developed enough to test, but that doesn't make them useless any more than the Axiom of Choice.

This looks like a load of semantic (philosophical, and political) BS.
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Astronomy Papers That Caught Fred's Eye In Today's arXiv
 
There are sixty-nine new papers admitted into Astro-archives today. Topics which 'caught my eye' include:

Problems and Prospects from a Flood of Extragalactic TeV Neutrinos in IceCube http://arxiv.org/abs/1511.01530
This is a frank overview; an essay explaining why the Neutrino background cannot be closely correlated with the cosmic gamma ray background; and there is no apparent correlation with objects, such as active galactic nuclei. Clearly IceCube is trying to teach us something...but what? See also: Active Galactic Nuclei as High-Energy Neutrino Sources http://arxiv.org/abs/1511.01590

Radio SETI Observations of the Anomalous Star KIC 8462852 http://arxiv.org/abs/1511.01606 This paper caught my eye because I was not aware there are on-going SETI searches for intelligent life. Spoiler alert: Nothing suspiciously alien.

Historical Reflections on the Work of IAU Commission 4 (Ephemerides) http://arxiv.org/abs/1511.01546 This is a fun account of the work of the IAU on the determination of Planetary Ephemerides; including reference systems. The work has been discontinued largely because computerized space systems controlled by JPL and other entities are doing all of the heavy lifting.
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Astronomy Papers That Caught My Eye In Today's arXiv

There are 68 papers today (Wednesday), not counting replacements. 

Topics: SMBH Seeds, Binary NS Constraints, THz Telescopes

SMBH Seeds http://arxiv.org/abs/1511.00696 Here's another look at Direct Collapse scenarios. In this case it is looking at situation in which there are bright sources of ultraviolet light (star-forming protogalaxy) from 3000 to 12,000 light years away from a dense collection of un-ionized Hydrogen. Their simulation shows that this environment can lead to the formation of a massive star with a core between 5000 and 10,000 times the mass of the Sun, which itself can lead to a direct collapse black hole.

Binary NS Constraints http://arxiv.org/abs/1511.00753 This is another Gravitational Wave paper anticipating what future observations will mean. In this case it is about what the GWs can tell us about limits on the neutron star equation of state from occasions when a binary neutron star merges and produces a short Gamma Ray Burst.

THz Telescopes http://arxiv.org/abs/1511.00839 There are some millimeter-wave telescopes on high mountains with dry air. The air becomes less transparent at wavelengths below 1mm, but this paper looks at the scientific case for making large ground-based telescopes that work near 300 microns. At high altitude locations, the atmosphere absorbs about 85% of the photons coming from outside, but that still leaves light carrying important information about star-forming regions, dust, GRB afterglows, and other phenomena not easily seen at other wavelengths.
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Astronomy Papers That Caught My Eye In Today's arXiv

There are 90 papers today (Tuesday), not counting replacements. 

Topics: Superfireball History, New Idea for Exoplanet Spectra, Gravitational Waves

Superfireball History http://arxiv.org/abs/1511.00464 This team gathered newspaper reports about big meteors from the last 150 years, and found that only a few of the large ones are connected to known recurring showers.

New Idea for Exoplanet Spectra http://arxiv.org/abs/1511.00508 Densified Pupil Spectroscopy is a way of dividing the pupil into subpupils and selecting dynamically which subpupil is being fed to the spectrometer. This is important because telescope deformation and jitter make it difficult to keep an exoplanet targeted with a ground-based telescope.

Gravitational Waves http://arxiv.org/abs/1511.00231 Since Gravitational Wave detection is expected soon (now to a few years from now), there are a lot of papers and popular press articles about them (There's a nice one in the December 2015 Sky & Telescope). This is a summary paper about methods of detection, instrument sensitivities (past, current, and near future), and the sources of the waves as anticipated by what we already know about the universe. Nice charts on pages 10 & 11.
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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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how does the GRB curve fit with the LIGO data? when the news was released it seemed  that no optical counterpart was even expected to be seen. detecting a GRB will only bolster the gravity of the situation.
verifying that gravity waves propagate at C is a bit disappointing. no chance of super luminal comms and we are stuck here to just observe the wash of photons. oh well, it does make gravity easier to understand and provides a nice upper limit to C.
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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.
Abstract: The dynamical formation of stellar-mass black hole-black hole binaries has long been a promising source of gravitational waves for the Laser Interferometer Gravitational-Wave Observatory (LIGO). Mass segregation, gravitational focusing, and multibody dynamical interactions naturally ...
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+Jay Cross! Did you see http://arxiv.org/abs/1511.08801 and http://arxiv.org/abs/1512.04661 (pop treatment: http://www.nao.ac.jp/en/news/science/2016/20160115-nro.html ) and https://pbs.twimg.com/media/Cbnc-pkUkAEMOYj.jpg:large ? The NuSTAR galactic survey identifying those sources has been tied up in peer review for over a year.
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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.
The countdown begins to the crash of the world's platinum market.
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+Eko Prasetyo It is arguable. I'm not sure there is a right to give, or a right to deny. My hope is that people will handle this responsibly, but I have doubts there too.
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Astronomy Papers That Caught Fred's Eye In Today's arXiv
 
There are seventy-nine new papers accepted into Astro-archives today(!) Topics which caught-my-eye include: Fullerenes, magnetic monopoles, Gamma ray bursts, "twin" supernova Ia.

Interstellar Fullerene Compounds and Diffuse Interstellar Bands http://arxiv.org/abs/1511.01250 So why is the sky black? It is not; at least no in the Infrared bandwidth; and lots of dark patches are emitted IR regions: Interstellar bands. Thought to be made up of mostly carbon, interstellar bands are a mystery in terms of what they are and why are they everywhere. One possibility is that they are composed largely of fullerenes: Three dimensional carbon structures midway between graphite and diamond. Fullerenes are easy to form in hot, oxygen starved environments; and they are highly stable molecules that lack spectral identities: In other words, perfect candidates for interstellar bands.

Searches for Relativistic Magnetic Monopoles in IceCube http://arxiv.org/abs/1511.01350 A magnetic monopole; a particle with only a positive or negative charge, could be quickly accelerated to relativistic speeds; and it would likely leave a tale-a-tale path through a large array of detectors, such as the IceCube. Researchers have searched the IceCube data for clues, and found zilch. This paper publishes these new constraints.

Gamma Ray Bursts as Neutrino Sources http://arxiv.org/abs/1511.01396 Another 'hoped for' result of the IceCube's sensitive detectors is streams of neutrino's that can be associated with gamma ray burst sources. But not today.

Improving Cosmological Distance Measurements Using Twin Type Ia Supernovae http://arxiv.org/abs/1511.01102 Supernova type Ia are still the best indicators of cosmic distances; however, the range of known magnitudes is broader than expected. One way to reduce the scatter may be to 'twin' events with highly similar spectral features and compare this hybrid with earlier techniques
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Why should fullerenes lack spectral identities? Too many degrees of freedom? Too many variants? Alas, they became a thing after grad school, so I never learned about them and haven't found a good reference/review article since. (Wikipedia falls down on this particular question.)
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Astronomy  - 
 
Astronomy Papers That Caught My Eye In Today's arXiv

There are 68 papers today (Wednesday), not counting replacements. 

Topics: SMBH Seeds, Binary NS Constraints, THz Telescopes

SMBH Seeds http://arxiv.org/abs/1511.00696 Here's another look at Direct Collapse scenarios. In this case it is looking at situation in which there are bright sources of ultraviolet light (star-forming protogalaxy) from 3000 to 12,000 light years away from a dense collection of un-ionized Hydrogen. Their simulation shows that this environment can lead to the formation of a massive star with a core between 5000 and 10,000 times the mass of the Sun, which itself can lead to a direct collapse black hole.

Binary NS Constraints http://arxiv.org/abs/1511.00753 This is another Gravitational Wave paper anticipating what future observations will mean. In this case it is about what the GWs can tell us about limits on the neutron star equation of state from occasions when a binary neutron star merges and produces a short Gamma Ray Burst.

THz Telescopes http://arxiv.org/abs/1511.00839 There are some millimeter-wave telescopes on high mountains with dry air. The air becomes less transparent at wavelengths below 1mm, but this paper looks at the scientific case for making large ground-based telescopes that work near 300 microns. At high altitude locations, the atmosphere absorbs about 85% of the photons coming from outside, but that still leaves light carrying important information about star-forming regions, dust, GRB afterglows, and other phenomena not easily seen at other wavelengths.
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Jay Cross

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Astronomy Papers That Caught My Eye In Today's arXiv

There are 90 papers today (Tuesday), not counting replacements. 

Topics: Superfireball History, New Idea for Exoplanet Spectra, Gravitational Waves

Superfireball History http://arxiv.org/abs/1511.00464 This team gathered newspaper reports about big meteors from the last 150 years, and found that only a few of the large ones are connected to known recurring showers.

New Idea for Exoplanet Spectra http://arxiv.org/abs/1511.00508 Densified Pupil Spectroscopy is a way of dividing the pupil into subpupils and selecting dynamically which subpupil is being fed to the spectrometer. This is important because telescope deformation and jitter make it difficult to keep an exoplanet targeted with a ground-based telescope.

Gravitational Waves http://arxiv.org/abs/1511.00231 Since Gravitational Wave detection is expected soon (now to a few years from now), there are a lot of papers and popular press articles about them (There's a nice one in the December 2015 Sky & Telescope). This is a summary paper about methods of detection, instrument sensitivities (past, current, and near future), and the sources of the waves as anticipated by what we already know about the universe. Nice charts on pages 10 & 11.
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One of a long line of Renaissance Men
Introduction
Publicly, I post a lot of astronomy stuff. I also post about politics, my life, the future, and links to my photo journal to people in specific circles.

Bragging rights
It seems impolite for me to say all the great stuff I've been lucky enough to do.
Education
  • Rensselaer Polytechnic Institute
    Physics, 1973 - 1979
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I've gone by "antoniseb" on the web, and in the Society for Creative Anachronism, I'm called "Anton of Winteroak"
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I'm a technical trainer for enterprise software systems
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    Technical Trainer, 2011 - present
  • Art Technology Group
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