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1 hour ago, coda said:

I read the waves 'convey' energy 50 times greater than all the stars in the universe. Don't understand.

A ~36 M_sun BH and a ~ 29 M_sun BH merged to form a ~62 M_sun BH hole. You'll notice that 3 M_sun went missing, i.e., this mass powered the gravitational wave emission. Using mc^2, we get of order 1e55 erg/s. The sun has a luminosity of ~ 4e33 erg/s, and the largest O star might have a luminosity of 1e39 erg/s. There are very few O-type stars relative to sun like stars and very few sun like stars in comparison to stars with luminosity much less than the sun.

For reference a typical SNe would generate 1e51-53 erg/s in the electromagnetic channel, and gamma-ray burst have been seen to do similar, which shouldn't be all that surprising as BHs are being formed in lots of them also.

Orders of 10 are fun!

Edited by villakram
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1 hour ago, tonyh29 said:

I mentioned a small bit of it once before in another thread but from my limited understanding Einstein basically proved that Newton was wrong  ....  Einstein's theory had already been proven to be correct beyond any reason (I think ) but theses waves sorta double confirm that he was correct beyond any reason ...

per the LIGO team paper on GR tests/implications

"The constraints provided by GW150914 on deviations from GR are unprecedented due to the nature of the source, but they do not reach high precision for some types of deviation, particularly those affecting the inspiral regime. A much higher SNR and longer signals are necessary for more stringent tests. However, it is not clear up to which SNR our parameterized waveform models are still a faithful representation of solutions of Einstein’s equations. Furthermore, to extract physical effects we need waveform models that are parameterized in terms of those physical effects. We hope that, following GW150914, further efforts will be made to develop reliable, physical and computationally fast waveform models. More stringent bounds can be obtained by combining results from multiple GW observations [58, 82, 83, 93]. Given the rate of coalescence of binary black holes as inferred in Ref. [101], we are looking forward to the upcoming joint observing runs of LIGO and Virgo.

So, yup... all good for GR but much more stringent tests to be done/required.

Edited by villakram
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On 21/01/2016 at 08:51, Chindie said:

The theory, that's been around for a while, that there's a new 9th planet beyond Pluto (which obviously got demoted from 9th planet a decade ago), seems to have gained some credence this week, and there's now a push to get as many people as possible looking for it...

I wonder what the name would be? Who's the next Roman deity in line? Or do we go new age?

Apparently it's the most planetty planet of all the planets.

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The new X-ray observatory Hitomi may be kaput... no communication, orbital period change, some associated debris spotted and optical observations suggest it's rotating in an uncontrolled manner. :( 

https://twitter.com/jaxa_en

"Communication anomaly of X-ray Astronomy Satellite “Hitomi” (ASTRO-H). "

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Quote

Diamonds turn nuclear waste into nuclear batteries

How to dispose of nuclear waste is one of the great technical challenges of the 21st century. The trouble is, it usually turns out not to be so much a question of disposal as long-term storage. If it was simply a matter of getting rid of radioactive material permanently, there are any number of options, but spent nuclear fuel and other waste consists of valuable radioactive isotopes that are needed in industry and medicine, or can be reprocessed to produce more fuel. Disposal, therefore is more often a matter of keeping waste safe, but being able to get at it later when needed.

One unexpected example of this is the Bristol team's work on a major source of nuclear waste from Britain's aging Magnox reactors, which are now being decommissioned after over half a century of service. These first generation reactors used graphite blocks as moderators to slow down neutrons to keep the nuclear fission process running, but decades of exposure have left the UK with 95,000 tonnes (104,720 tons) of graphite blocks that are now classed as nuclear waste because the radiation in the reactors changes some of the inert carbon in the blocks into radioactive carbon-14.

Carbon-14 is a low-yield beta particle emitter that can't penetrate even a few centimeters of air, but it's still too dangerous to allow into the environment. Instead of burying it, the Bristol team's solution is to remove most of the c-14 from the graphite blocks and turn it into electricity-generating diamonds.

The nuclear diamond battery is based on the fact that when a man-made diamond is exposed to radiation, it produces a small electric current. According to the researchers, this makes it possible to build a battery that has no moving parts, gives off no emissions, and is maintenance-free.

New Atlas

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To be fair, I don't think 'a Kickstarter campaign' can be considered 'scientific media', nor is this guy a scientist in any obvious way. 

Thank you for bringing the scam to our attention though, it is important to know. 

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53 minutes ago, MakemineVanilla said:

Always trust scientists and scientific media.

The Waterseer has already raised $330k

 

I'm confused. The only science in that video is saying that it's impossible. Who don't you think we should trust?

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