The science behind RHCs liver thread

This has links to the kind of media response.

https://www.google.co.uk/amp/s/amp....ments/6sfs9x/the_google_manifesto_megathread/

Edit...tbe link to memo is at the top.

If you scroll down to the comments there is a pdf file with an unedited version of the memo the employee sent.

This I read this morning with about 500 tweet debate in response by various scientists...rights groups etc..

https://www.theglobeandmail.com/opi...sity-its-science/article35903359/?service=amp

 

Summery. I'm not going through that ****ing lot, Frank

 

Lol.

Basically this guy believes that Google's enforced drive for 50 50 representation in its employees is a flawed politically driven policy that hurts productivity, fosters resentment and jyst won't produce the outcome the company is going for.

He cites several scientific papers/ studies that come to the conclusion that men and women have biological differences that cause different tendencies towards neurosis, reaction to stress, etc that mean each sex while not exclusively (he is at pains to say he wants to avoid stereotypes ) migrate towards certain professions.

He also points out that as real equality and freedom to choose professions becomes more available to women you will/are seeing a bigger gender divide growing in his type of industry because women just don't want or can't cope with demands in specific jobs that men can and vice versa.

He was immediately sacked for pandering to old stereotypes and being anti diversity.

The liberal press hammered him for the same while being quite naughty and publishing an edited version of his memo with the citations removed.

One female scientist actually said that while his memo was ham fisted and badly laid out the science he quotes is an accurate portarayal of a big chunk of thinking in the area.

As I said in my first post. It felt to me that his reasoning has been dismissed immediately for political reasons rather than people refuting the science he used to base his arguments on.

The comparison that came to my mind reading it all was this. Primary School teachers are overwhelmingly female. Following Google's model they would prefer substandard teachers as long as it resulted in 50 50 men/women teachers. That they believe it is social engineering that doesn't steer men to ps teaching rather than at least part of it being biological.

I'm not a scientist in the field so can not argue the details either way....but....to me it seems he is being dismissed because it doesn't suit the political agenda rather than showing how the scientific arguments he used were flawed.

Sounds very similar to how the far right corporate guys dismiss climate change science because it doesn't suit their agenda.

 

Thanks.

 

It was about pay gaps but it sounded like the guy was sayingwomen made bad engineers.

The issue for me boils down to 3 things

1. Feminists want to ignore the fact that women in power will pay women less ( all about the bottom line)

2. It takes actual time for women to gain experience to be cos and board members. The situation has radically improved over 20 year and will keep improving but certain people want it now irrespective of ability

3. Feminists don't want to hear women are not perfect. If you dare say excuse me but you accepted that wage you are a sexistpig. They miss the point that some of us are trying to encourage them to know their value and negotiate better.

Women just need to do the research, find the job value and go in and hard ball bosses.

The women who are bosses exploit women just as much as men and will pay that 5 or 10k less cos you bloody accepted it.

The guy who wrote the Google memo was a ****ing idiot who's career is now over. NEVER PUT IT IN WRITING.

 

Btw the reason the vast majority of primary teachers are women and then teacher of older children become a bit more balanced is really simple.

Really simple.

Thry get called peados.

There I said it, it's not about money or education it is the fact the parents look at you funny.

Same for nurses. Some men do it, a few more go to psychiatric nursing but in the end you get looked at funny.

Imo there is zero reason for assuming a 50/50 mix in government, work or caring would make the blinders difference.

The great assumption feminists make is that if women were in charge there would be no wars... **** off.. her name was Thatcher.

Women are just as good as men at everything... including corruption and backfiring and war mongering. They play the system just as well as men. The system is a LOT HARDER to change than attitudes to sex.

Profits are profits after all.

 

That's the claim made by those who refuse to accept the science countering it. "Oh, we're not allowed to speak," which is bullshit. Nobody denies freedom of speech to climate change deniers, they're countered with science, just as these claims have been.

There's a lot of science to this, much of it old and based on evolution, which has some credence, though much of the new science is blowing away accepted ideas about gender, for example:

https://www.newscientist.com/articl...eres-no-such-thing-as-a-male-or-female-brain/

Do tell us which feminists you've read which have brought you to this conclusion that you can stereotype feminists in this offhand way, like there's some kind of United Nations committee of butch lesbians making decrees, with an agenda to castrate all men...sorry, sexist pigs. This is typical blokey bollocks about feminism - "Oh, women are just as bad as men" - well, yes, when they're given an equal chance, they are. So ****ing what? They're not given an equal chance, THAT'S THE ****ING POINT! Do you know how many women bosses there are actually are?

http://fortune.com/2016/06/06/women-ceos-fortune-500-2016/

This is not because they didn't take the time to gain the experience, because they were too busy painting their pretty nails and squeezing out bairns.

Whenever there's an article about domestic violence, there's a bunch of blokes whining about some bloke their mate's cousin knew who got hit by a woman, which makes it all even and feminism is just a pile of hypocrisy. They're not actually bothered about that bloke - they think he's a bit of a pussy who should man up - but he's a handy stick to fight back against feminism, which their masuclinity has felt threatened by. How many of them have started refuges for blokes who are escaping violent relationships? Yes, some women hit men. But some men don't realise that feminism is fighting all domestic violence. Ditto false rape allegations. Some men fail to grasp that if it were investigated more thoroughly than it is, false claims would also be better investigated.

There are women who exploit women just as much as men. But there are women who also try to repair the damage centuries of male dominance has brought. It's estimated that the gender pay gap won't be closed until next century at the current rate.

You do men no favours with your simplistic bollocks and I suggest you actually read some feminists before expounding on what it is and isn't. Y'know, "just do the research," like you suggest women just need to do. Try Caitlin Moran first. She's actually funny, which makes it easier for men to read without having ridiculous kneejerk reactions.

https://www.amazon.co.uk/How-Be-Woman-Caitlin-Moran-ebook/dp/B0052CK5PQ

 

I'm sterotyping a couple who got very very irate if someone happens to say "man power" in a training course for example i was an innocent bystander btw.

What some people don't realise that in quite a lot of places (not all obviously) the door is wide open for women and they only need walk through.

the point i made which i will reiterate is that women in power that other women exactly the same. why do you think there is a gender pay gap in many industries.

I've seen women CEOs, directors middle managers and they all get in line with "the system" as i described and on goes the pay gap.

As i said, when women said up and focus more on themselves rather than men they would educate each other in the women's networks that they have to negotiate better and harder and have more confidence in themselves

You know many now claim the whole system is against them down to dolls in shops for toddlers teaching girls to be less confident and subserviant? Its maddening that the key point is every woman i've met in business is just as capable and just as skilled as anyone else yet they end up accepting less.

The first point should be understand your level, understand the market rate and be confident in your ability.

I'm saying i've seen this stuff day in and day out...

I'm also replying to the point on this google idiot who wrote a very stupid document. Unfortunately his point was if you go just hire 50/50 gender you won't solve the problem. Unfortunately he then went about quoting stuff about women that was in effect a red rag to a bull.

My point is if you have industry already where the pay gap exists and theres between 30-50% women working AND you've a good proportion of women up the chain its the system not men doing it.

The first place to look is at yourself always. No matter what gender. Know your worth. know your own failings too.
thats all....

The women's networks i have personally seen in action become very quickly preaching to the converted, become in crowds almost cos its easy stick to the outside forces rather than first focusing on development.

Any woman in business gets the same advice from me as any man.

1. know the business

2. know your worth.

3. don't accept any less that your worth.

 

Except the claims weren't countered by Google or the media by science they were dismissed arbitrarily with name calling.

I'm not backing his science..I stated I wasn't qualified to do so. My point was:

A) his employer didn't refute his argument with counter research, they simply dismissed it and sacked him labelling him anti diversity and sexist: something he states clearly he is not and that he agrees with the end goals of Google but simply disagrees it's possible the way they are trying to achieve it.

So that's a pretty clear message that he is in fact not allowed to speak lol. Don't get me wrong I found it a bizarre Jerry Maguire type course of action on his part but then I assumed Google probably encourage this type of bullshit...as long as it conformed obviously lol.

By all means if they'd pulled him in and presented him with the resources they believe refute his science and explained that's what they based their policies on and he STILL continued speaking out...feel free to sack him. Feck me there's guys kept their jobs for inappropriate behaviour just sent on awareness courses...

B) the media for at least the first 24 hours didn't point to evidence based critique of his science they just attacked the man. And as I stated, naughtily removed his citations to make it appear as if he wasn't presenting evidence (whether it's old new bad or good science) just a ranting mysoginist.

And this was my concern. There is an indication that many in the media or PR sensitive positions are not willing to take the time to answer a scientific argument with more science....because I suspect it's boring and won't get the clicks and to maintain a PC image at all costs...id personally rather they took the time.

A perfect example being Radio 4 insisting on bringing Lawson on as a climate denier everytime they debate it. He's not a scientist he's a has been politician so it's not "to balance the debate" as argued by the BBC.

It's because it gets attention....god forbid you bring on someone nutter like Salby so he can get destroyed with his meaningless charts...no that wouldn't get a response though...that wouldn't capture numbers...

 

Gene editing creates virus-free piglets
Advance moves the animals one step closer to becoming organ donors for people
BY
TINA HESMAN SAEY
2:00PM, AUGUST 10, 2017

please log in to view this image

THREE LITTLE PIGS Researchers are working to create pigs that can donate organs for human transplant. These piglets are part of the first litter of pigs engineered to lack viruses called PERVs.

EGENESIS

• Email
• Twitter
• Facebook
• Reddit
• Google+

SPONSOR MESSAGE
Pigs are a step closer to becoming organ donors for people.

Researchers used molecular scissors known as CRISPR/Cas9 to snip embedded viruses out of pig DNA. Removing the viruses — called porcine endogenous retroviruses, or PERVs — creates piglets that can’t pass the viruses on to transplant recipients, geneticist Luhan Yang and colleagues report online August 10 in Science.

Yang, a cofounder of eGenesis in Cambridge, Mass., and colleagues had previously sliced 62 PERVs at a time from pig cells grown in the lab (SN: 11/14/15, p. 6). Many of the embedded viruses are already damaged and can’t make copies of themselves to pass on an infection. So in the new study, the researchers removed just 25 viruses that were still capable of infecting other cells.

The team had to overcome several technical hurdles to make PERV-less pig cells that still had the normal number of chromosomes. In a process similar to the one that created Dolly the Sheep (SN: 3/1/97, p. 132), researchers sucked the DNA-containing nuclei from the virus-cleaned cells and injected them into pig eggs. The technique, called somatic cell nuclear transfer, is better known as cloning. Embryos made from the cloned cells were transplanted to sows to develop into piglets.

The process is still not very efficient. Researchers placed 200 to 300 embryos in each of 17 sows. Only 37 piglets were born, and 15 are still living. The oldest are about 4 months old. Such virus-free swine could be a starting point for further genetic manipulations to make pig organs compatible with humans.

 

Cosmic lens lets astronomers zoom in on a black hole’s burps
Seeing into the heart of a faraway galaxy could explain how jets of hot material get their start
BY
LISA GROSSMAN
5:01PM, AUGUST 18, 2017

please log in to view this image

REACHING OUT Many supermassive black holes shoot jets of hot material thousands of light-years into space, like this one emerging from the galaxy M87 about 50 million light-years away. Now scientists have seen the beginnings of such a jet from a galaxy billions of light-years away.

HUBBLE HERITAGE TEAM (AURA/STSCI), NASA, ESA

• Email
• Twitter
• Facebook
• Reddit
• Google+

SPONSOR MESSAGE
Astronomers have caught their best look ever at blobs of hot gas fleeing a supermassive black hole, thanks to a new kind of cosmic magnifying glass.

Anthony Readhead of the Owens Valley Radio Observatory at Caltech and colleagues caught two small, hot bursts traveling away from a bright galaxy called J1415+1320 at near the speed of light. Although the galaxy is billions of light-years away and the blobs are tiny compared with the galaxy, it appears that a lucky alignment of stars may have created what’s called a gravitational lens, magnifying the galaxy and its environs.

“We’re peering right down into the core of the nucleus of this active galaxy,” Readhead says. “We think this is potentially a very powerful new window.” The researchers report their findings August 20 in two papers in the Astrophysical Journal.

J1415+1320 is what’s known as a blazar, a bright galaxy with a gluttonous supermassive black hole at its center (SN: 3/4/17, p. 13). The black hole is actively feeding on a disk of white-hot gas that swirls around it, making the host galaxy glow brightly in gamma and radio waves. The galaxy is among about 1,800 blazars that Readhead and his team have observed twice a week since 2008. “Nobody has looked at the sky quite like that before,” he says.

The stars are aligned
The start of a jet in the distant galaxy J1415+1320 was magnified by a massive object in the foreground, closer to Earth. That object is associated with an intervening galaxy, but is less massive — it could be a collection of stars or midsize black holes.

please log in to view this image

ANTHONY READHEAD/CALTECH/MOJAVE


Starting in 2009, J1415+1320 started doing something extremely strange. Over the course of about a year, the blazar grew brighter, then dimmer, then brighter again. Plotting its brightness over time revealed a symmetrical U shape in the data.

At first, the team thought the change was caused by a cloud of plasma within the Milky Way that happened to pass between Earth and the blazar, scattering its light. But then the same thing happened again in 2014.

Conversations with colleagues at other observatories revealed that the galaxy behaved the same way when observed in many electromagnetic wavelengths, not just with a radio telescope. That wouldn’t happen if a stray cloud of plasma were to blame.

Now, Readhead and his colleagues argue that they’re seeing the blazar’s black hole emit tiny burps of plasma, magnified hundreds of times by a new kind of gravitational lens. These cosmic lenses are massive objects that can bend the path of light passing by them, making sources of light in the background look distorted from the point of view of telescopes on Earth. Astronomers can use this distortion to learn about the background objects and their lenses.

So far, all known lenses have either been enormous — millions of times the mass of the sun, like an entire galaxy — or relatively tiny, like a single planet.

The lens that magnified J1415+1320 seems to be something in between, from 1,000 to 1 million times the mass of the sun. It is about 2.7 billion light-years away, and is associated with a spiral galaxy, but is less massive than the entire galaxy. The lens could lie within or nearby the galaxy, and could be a collection of thousands of stars like a globular cluster. Or it could be something more exotic, like difficult-to-spot midsize black holes.

The U-shaped features in the data appeared when the black hole emitted clumps of matter that sped away at near the speed of light, and passed behind this lens from the perspective of Earth, the team says.

Now ‘U’ see it
Distant galaxy J1415+1320 dimmed and brightened over the course of a year in 2009 and 2014 (shaded regions), causing a U-shaped dip in the data used to track its brightness. That dip was caused by blobs of hot plasma emitted by the galaxy’s black hole, which were magnified by a cluster of stars acting as a cosmic lens between Earth and the galaxy, researchers suggest. This plot shows observations of the galaxy from the Owens Valley Radio Observatory in California (black), the Metsähovi Radio Observatory in Finland (blue) and the Submillimeter Array in Hawaii (red).

please log in to view this image

H. VEDANTHAM/CALTECH


“This was an extremely interesting, unique observation,” says astrophysicist Eileen Meyer of the University of Maryland, Baltimore County. “As far as I know, there’s nothing like that that has been observed before.”

Readhead’s team still needs to make more observations to confirm that the lens is real. But if it is, it could help solve an outstanding mystery about black holes: how they shoot jets of hot charged particles into space. Many active galaxies display these brilliant jets, but their origins are mysterious.

“We actually don’t know how these jets are launched,” says Harish Vedantham, also of Owens Valley Radio Observatory and a coauthor of the new papers. “We don’t have definitive answers because we can’t make an image on the [size] scales of where this emission is happening.”

The new observations of J1415+1320 are not quite such an image. But they suggest a way to someday produce one. The lens magnified the black hole 100 times more than is possible with current telescopes, so more observations could help reveal more about its nature.

“This is like a stepping-stone,” Vedantham says. “This is a possible technique to go in and get this high-resolution view of how a black hole is launching these jets.”

If further observations rule out the lens, then things could get even stranger. “If it’s not a gravitational lens, then it’s an intrinsic property of the jets themselves,” Readhead says. “Then it will have interesting implications for the physics of the actual jet. I think it’s a win-win situation.”

 

We share the Milky Way with 100 million black holes
New census estimates the number of cosmic chasms based on galaxy size and makeup
BY
EMILY CONOVER
9:00AM, AUGUST 18, 2017

please log in to view this image

CRUNCH THE NUMBERS Scientists estimate that the Milky Way contains 100 million black holes.

AVIGATORPHOTOGRAPHER/ISTOCKPHOTO

• Email
• Twitter
• Facebook
• Reddit
• Google+

SPONSOR MESSAGE
The Milky Way teems with black holes — about 100 million of them.

But there’s no reason to fear. “It may sound like a big number, but by astronomical standards, it’s a pretty small number,” says physicist Daniel Holz of the University of Chicago. The number of stars in the Milky Way, for example, is about a thousand times larger.

Scientists from the University of California, Irvine calculated the galaxy’s black hole population as part of a new census that estimates the numbers of cosmic chasms in galaxies big and small. The analysis, in press in Monthly Notices of the Royal Astronomical Society, quantified stellar-mass black holes, which form when a star collapses. Such objects can have masses tens of times that of the sun.

To draw up the celestial inventory, the researchers combined a variety of information about stars and galaxies. A star’s size and composition — the proportion of heavy elements it contains — determine whether it can form a black hole, and how big the black hole will be. And given a galaxy‘s size, scientists can estimate the number and properties of stars within, allowing researchers to deduce the number of black holes and their sizes.

Such stellar-mass black holes are a target of the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, which has detected three sets of gravitational wavesfrom colliding black holes (SN: 6/24/17, p. 6). When LIGO made its first detection, some physicists thought the coalescing black holes were surprisingly large; each was about 30 times the mass of the sun (SN: 3/5/16, p. 6). This puzzle led scientists to propose exotic origins for LIGO’s black holes — for example, that they formed during the universe’s infancy, instead of from collapsing stars (SN: 9/3/16, p. 8).

But the new result indicates that, in the Milky Way alone, there are about 10 million black holes with masses at least that large. So “you don’t have to do anything particularly odd or unusual in order to explain the LIGO signal,” says physicist James Bullock, a coauthor of the study.

Astrophysicist Richard O'Shaughnessy of the Rochester Institute of Technology in New York isn’t surprised by the abundance of big black holes. But, he says, the new work may serve to placate researchers who thought LIGO’s large black holes were an oddity. “Hopefully this sort of presentation will make even the skeptics recognize that this is logical.”

 

Trio wins physics Nobel Prize for gravitational wave detection
Prize comes quickly for LIGO masterminds
BY
EMILY CONOVER
LISA GROSSMAN
6:08AM, OCTOBER 3, 2017

please log in to view this image

LIGO PIONEERS Rainer Weiss of MIT (left), and Kip Thorne (middle) and Barry Barish (right), both of Caltech, won the Nobel Prize in physics for their leadership roles in the LIGO experiment.

FROM LEFT: BRYCE VICKMARK; CALTECH; R. HAHN/WIKIMEDIA COMMONS

• Email
• Twitter
• Facebook
• Reddit
• Google+

SPONSOR MESSAGE
View the video

Subtle cosmic vibrations kicked up by swirling black holes have captured the public imagination — and the minds of the physics Nobel Prize committee members, too.

Three scientists who laid the groundwork for the first direct detection of gravitational waves have won the Nobel Prize in physics. Rainer Weiss of MIT, and Kip Thorne and Barry Barish, both of Caltech, will share the 9-million-Swedish-kronor (about $1.1 million) prize, with half going to Weiss and the remainder split between Thorne and Barish.

Though researchers often wait decades for Nobel recognition, the observation of gravitational waves was so monumental that the scientists were honored less than two years after the discovery’s announcement.

“These detections were so compelling and earth shattering…. Why wait?” says Clifford Will of the University of Florida in Gainesville, who was not directly involved with the discovery. “It’s fabulous. Absolutely fabulous.”

Weiss, Thorne and Barish are pioneers of the Laser Interferometer Gravitational Wave Observatory, or LIGO. On February 11, 2016, LIGO scientists announced they had spotted gravitational waves produced by a pair of merging black holes. This first-ever detection generated a frenzy of excitement among physicists and garnered front-page headlines around the world.

LIGO’s observation of gravitational waves directly confirmed a 100-year-old prediction of Einstein’s general theory of relativity — that rapidly accelerating massive objects stretch and squeeze spacetime, producing ripples that travel outward from the source (SN: 3/5/16, p. 22).

Story continues below illustration

please log in to view this image

RIPPLES TO RICHES The Nobel Prize was awarded to a trio of physicists for the detection of gravitational waves produced by two merging black holes, shown in a computer simulation.
C. HENZE/NASA


“If Einstein was still alive, it would be absolutely wonderful to go to him and tell him about the discovery. He would be very pleased, I’m sure of it,” Weiss said during a news conference at MIT a few hours after he got word of the win. “But then to tell him what the discovery was, that it was a black hole, he would have been absolutely flabbergasted because he didn’t believe in them.”

As enthusiastic team members clad in LIGO-themed T-shirts celebrated the discovery, Weiss stressed that the discovery was a group effort. “I’m a symbol of that. It’s not all on my shoulders, this thing,” he said, citing the large collaboration of scientists whose work led up to LIGO’s detection.

Physicists anticipate that LIGO will spark an entirely new field of astronomy, in which scientists survey the universe by feeling for its tremors. “It will allow us to see the parts of the universe that were not revealed to us before,” says LIGO team member Carlos Lousto of the Rochester Institute of Technology in New York.

minuscule undulations of their first black hole collision. Those ripples, spotted on September 14, 2015, journeyed to Earth from 1.3 billion light-years away, where they were produced by two colossal black holes that spiraled inward and merged into one (SN: 3/5/16, p. 6).

Quivers from those converging black holes, when converted into an audio signal, made a tell-tale sound called a "chirp," reminiscent of a bird's cry. The particulars of that signature reveal details of the collision. “The beauty of the symphony is in what you can extract from the tiny wiggles, or the wiggles on tops of wiggles, in that signal,” Thorne said at an Oct. 3 news conference at Caltech.

Story contines after video

SPACETIME SHIMMY Gravitational waves, explained here, garnered the 2017 Nobel Prize in physics. These tiny undulations in the fabric of spacetime are set off by violent cosmic events, such as the collision of two black holes.H. THOMPSON

Since that first detection, scientists have observed three more black hole collisions. And additional gravitational ripples may already be in the bag: It’s rumored that LIGO scientists have also detected a smashup of neutron stars (SN Online: 8/25/17). In fact, Weiss teased an announcement to come on October 16.

An astounding feat of engineering, LIGO consists of two enormous L-shaped detectors that stretch across the wooded landscape of Livingston, La., and the desert of Hanford, Wash. Each detector boasts two 4-kilometer-long arms through which laser light bounces back and forth between mirrors.

Gravitational waves passing through a detector stretch one arm while shortening the other. LIGO compares the arms’ sizes using the laser light to measure length differences a tiny fraction of the size of a proton. Gravitational waves should produce signals in the two distant detectors nearly simultaneously, helping scientists to rule out spurious signals that can be caused by events as mundane as a truck bouncing along nearby.

“LIGO is probably one of the best and most amazing instruments ever built by mankind,” Barish said at the Caltech news conference. But building it was a risky endeavor: No one had previously attempted anything like it, and no one could say for sure whether the effort would succeed. “What’s fundamental is you have to be willing to take risks to do great things,” Barish said.

In August, LIGO’s two detectors teamed up with the similarly designed Virgo detector near Pisa, Italy (SN Online: 8/1/17). The latest gravitational wave sighting, made on August 14, showed up in all three detectors almost simultaneously, which allowed scientists to pinpoint the region of space in which the black holes resided more precisely than ever before (SN Online: 9/27/17).

Weiss spent decades on the project, beginning with nascent scribbles on scraps of paper and early prototypes. In the 1960s, Weiss came up with the idea for a laser gravitational wave detector while teaching a class on general relativity. (Other researchers had independently proposed the technique as well.) He refined that idea and built a small, prototype detector, establishing the basic blueprint that would eventually evolve into LIGO.

Story continues below diagram

Catching waves
LIGO detects gravitational waves by splitting a laser beam in two, sending light down each arm. The light reflects back and forth between mirrors in the arms, before the beams recombine and are sent to a detector. If the arms are the same length, the light beams will cancel each other out. Any length difference — such as that caused by gravitational waves stretching one arm while squeezing the other — will allow some light through to the detector.

please log in to view this image

NICOLLE RAGER FULLER


Inspired by a conversation with Weiss, Thorne, who had been studying theoretical aspects of gravitational waves, assembled a team to work on the technique at Caltech in the ’70s. (Thorne was a 1958 semifinalist in the Science Talent Search, a program of the Society for Science & the Public, which publishes Science News.)

Another LIGO founder, Ronald Drever, died in March. Drever, who had been working on gravitational wave detectors at the University of Glasgow, joined Thorne at Caltech in 1979. Weiss and Drever each worked individually on prototypes, before Weiss officially teamed up with Thorne and Drever in 1984 to create LIGO (SN: 3/5/16, p. 24). Drever did live to hear of the first detection, Will says, but “it’s sad that he didn’t live to see it all.”

Barish joined the project later, becoming director of LIGO in 1994. He stayed in that role for more than 10 years, elevating LIGO from scientists’ daydreams into reality. Barish oversaw construction and commissioning of the detectors, as well as initial gravitational wave searches. “He entered the experiment in a crucial moment, when it was necessary to bring the experiment to a different level, make it a big collaboration,” says Alessandra Buonanno of the Max Planck Institute for Gravitational Physics in Potsdam, Germany.

Speculation that LIGO would nab a Nobel began as soon as the discovery was announced. So the collaboration was not surprised by the honor. “We were certainly expecting this to happen,” says LIGO team member Manuela Campanelli of the Rochester Institute of Technology. Still, the lack of surprise didn’t dampen the mood of festivity. “I feel in a dream,” says Buonanno.

LIGO and Virgo are currently in a shutdown period while scientists tinker with the detectors to improve their sensitivity. The gravitational wave hunt will resume next year. Besides black hole mergers and neutron star smashups, in the future, scientists might also spot waves from an exploding star, known as a supernova. Upcoming detectors might sense trembles generated in the Big Bang, providing a glimpse of the universe’s beginnings.

And scientists may even find new phenomena that they haven’t predicted. “I await expectantly some huge surprises in the coming years,” Thorne said.

 

Nice. I like LEGO

 

Neutron star collision showers the universe with a wealth of discoveries
Detection of gravitational waves from smashup helps reveal where heavy elements are created
BY
EMILY CONOVER
10:00AM, OCTOBER 16, 2017

please log in to view this image

BRIGHT BURST After two neutron stars slammed together, scientists detected gravitational waves, a burst of gamma rays and a glow from ejected material, shown in this artist’s conception.

NSF, LIGO, A. SIMONNET/SONOMA STATE UNIV.

• Email
• Twitter
• Facebook
• Reddit
• Google+

SPONSOR MESSAGE
View the video

WASHINGTON — Two ultradense cores of dead stars have produced a long-awaited cosmic collision, showering scientists with riches.

The event was the first direct sighting of a smashup of neutron stars, which are formed when aging stars explode and leave behind a neutron-rich remnant. In the wake of the collision, the churning residue forged gold, silver, platinum and a smattering of other heavy elements such as uranium, researchers reported October 16 at a news conference in Washington, D.C. Such elements’ birthplaces were previously unknown, but their origins were revealed by the cataclysm’s afterglow.

“It really is the last missing piece” of the periodic table, says Anna Frebel, an astronomer at MIT who was not involved in the research. “This is heaven for anyone working in the field.” After the collision, about 10 times the Earth’s mass in gold was spewed out into space, some scientists calculated.

Using data gathered by about 70 different observatories, astronomers characterized the event in exquisite detail, releasing a slew of papers describing the results. A tremor of gravitational waves, spotted by the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, on August 17, provided the first sign of the cataclysm.

Light types

please log in to view this image

ROBERT HURT/IPAC/CALTECH, MANSI KASLIWAL AND GREGG HALLINAN/CALTECH, PHIL EVANS/NASA AND THE GROWTH COLLABORATION


Telescopes picked up the afterglow of two converging neutron stars in a variety of wavelengths of light, from ultraviolet (left, image from NASA’s Swift satellite) to infrared (middle, image from the Gemini South telescope) to radio waves (right, image from the Very Large Array).

“Already it is transforming our understanding of the universe, with a fresh narrative of the physics of stars in their death throes,” said France Córdova, director of the National Science Foundation, which funds LIGO.

A sequence of various types of electromagnetic radiation followed that gravitational trill, like musical instruments taking turns in a symphony. A burst of gamma rays segued into a glow of visible and infrared light, first spotted about 12 hours after the smashup. More than a week later, as those wavelengths faded away, X-rays crescendoed, followed by radio waves.

Combining gravitational waves with light from a neutron star merger is a long-held dream of astrophysicists. “The picture that you can put together by having all of those sources is synergistic,” says LIGO spokesperson David Shoemaker of MIT. “You can make inferences that otherwise would be impossible."

That detailed picture revealed the inner workings of neutron star collisions and the source of brief blasts of high-energy light called short gamma-ray bursts. Researchers also calculated how fast the universe is expanding and tested the properties of the odd material within neutron stars.

For astrophysicists, “this event is the Rosetta stone,” says LIGO member Richard O’Shaughnessy of the Rochester Institute of Technology in New York.

LIGO’s two detectors, located in the United States, registered an unmistakable sign of the upheaval: A shimmying of space itself that continued for about 100 seconds before cutting off. It was the strongest and longest series of spacetime ripples LIGO had ever seen. At that point, scientists knew they had something big, says LIGO member Vicky Kalogera of Northwestern University in Evanston, Ill. “The e-mails that were circulated said, ‘Oh my God, this is it.’”

That vibration was an indication of a cosmic crash: Whirling round each other as if on an ill-fated merry-go-round, two orbiting neutron stars spiraled closer and closer, until they converged. The neutron stars, whose masses were between 1.17 and 1.60 times that of the sun, probably collapsed into a black hole, although LIGO scientists were unable to determine the stars' fate for certain. LIGO has previously spotted mergers of swirling black holes with masses tens of times that of the sun (SN Online: 9/27/17); the smaller masses of the orbiting duo pointed the finger at neutron stars. And because black holes aren’t expected to emit light, the fireworks show that followed solidified the case for neutron stars.

LIGO’s sister experiment in Italy, Advanced Virgo, saw only a faint signal. That relatively weak detection helped narrow down where the convulsion occurred to “a part of the sky that was a blind spot of Virgo,” Kalogera says. That constrained the site to within a region of about 30 square degrees in the southern sky.

Just 1.7 seconds after the gravitational wave signal, NASA’s Fermi space telescope spotted a glimmer of gamma rays in the same neighborhood of the sky. Meanwhile, other telescopes swung into action, picking up a glow where none had been before. “We saw what looked like a new star,” says astronomer Edo Berger of Harvard University, who led a team that spotted the light with the DECam on the Blanco telescope in Chile. Berger’s was one of several teams that observed the blast’s light. That detection pinpointed the galaxy NGC 4993, 130 million light-years from Earth in the constellation Hydra, as the collision site. “There was this moment of disbelief: Wow, we actually did it. We found it,” Berger says.

Story continues below graphic

Brought to light

please log in to view this image

P.K. BLANCHARD, E. BERGER, PAN-STARRS, DECAM


After gravitational waves narrowed down the region of sky where two neutron stars collided, telescopes pinpointed a spot of light (right, indicated with red lines) where none had been before (left).

That afterglow also revealed an amazing story of stellar alchemy: With the stars’ death came the birth of elements. As the collision spurted neutron-rich material into space, a bevy of heavy elements formed, through a chain of reactions called the r-process (SN: 5/14/16, p. 9). In this process, which requires an environment crammed with neutrons, atomic nuclei rapidly gobble up neutrons and decay radioactively, thereby transforming into new elements, before resuming their neutron gorgefest. The r-process is thought to produce about half of the elements heavier than iron.

Scientists detected the characteristic glow of this process, called a kilonova, in follow-up observations. “Until this event, we had never directly seen anywhere in nature these heavy elements being forged. Now we have,” says Brian Metzger, a theoretical astrophysicist at Columbia University. “It is a feeling like you’ve discovered some kind of secret of nature.”

Previously, astrophysicists disagreed about where the r-process occurs: Two top candidates were exploding stars called supernovas (SN: 2/18/17, p. 24) and neutron star mergers. Although scientists can’t yet say whether all r-process elements are produced in neutron star mergers, the amount such collisions should produce appears large enough to explain the abundances found in the universe.

Story continues below graphic

Element factory

please log in to view this image

ROBERT HURT/IPAC/CALTECH


Light emitted after a neutron star collision showed signs of heavy elements present in the aftermath, confirming that certain elements (yellow) are produced in such mergers. Other elements are produced in different ways, including in exploding massive stars and dying low mass stars.

Additional riches were revealed by gamma rays. Scientists spotted a phenomenon called a short gamma-ray burst, a brief spurt of high-energy light, less than two seconds long. Such paroxysms are relatively common, appearing in the sky about 50 times a year. But finding their source is “a long-standing problem in astrophysics,” says theoretical astrophysicist Rosalba Perna of Stony Brook University in New York. The detection clinched it: Short gamma-ray bursts come from neutron star tête-à-têtes.

By studying how the neutron stars spiraled inward, astrophysicists also tested the “squishiness” of neutron star material for the first time. This extreme substance is so dense that a teaspoonful of it would have a mass of around a billion metric tons, and scientists don’t fully understand how it responds when squeezed, a property known as its “equation of state.” Measuring this property could give scientists a better understanding of the strange material. Although the results couldn’t pin down whether the neutron stars were squishy, some theories that predicted ultrasquishy neutron stars were ruled out.

Closing in

please log in to view this image

STEFANO VALENTI/UC DAVIS, DLT40 SURVEY


LIGO and Virgo used gravitational waves to narrow down the region (white outlines) where two neutron stars smacked into one another. NASA’s Fermi space telescope detected gamma rays from within the region outlined in yellow. Visible light from the crash allowed scientists to pinpoint the galaxy NGC 4993 (red dot).

The neutron stars’ union also gave researchers the opportunity to gauge the universe’s expansion rate, by measuring the distance of the collision using gravitational waves and comparing that to how much the wavelength of light from the galaxy was stretched by the expansion. Scientists have previously measured this property, known as the Hubble constant, through other means. But those measurements are in disagreement, leaving scientists scrambling to explain the discrepancy (SN: 8/6/16, p. 10).

Now, scientists have “a totally different, independent measurement,” says LIGO collaboration member Daniel Holz of the University of Chicago. The new measurement indicates that distantly separated galaxies are spreading apart at about 70 kilometers per second for each megaparsec between them. It falls squarely between the two previous estimates: 67 and 73 km/s per megaparsec. Though this collision can’t yet resolve the debate, future mergers could help improve the measurement.

“These are all just unbelievable, major advances,” Holz says. “It’s really been this insane thrill.”


The excitement has yet to die down. Take it from astronomer Ryan Foley of the University of California, Santa Cruz, whose team was the first to spot visible light from the merger: “This is certainly the biggest discovery of my career and probably will be the biggest discovery of my entire life.”

Researchers announced October 16 that Advanced LIGO (the Laser Interferometer Gravitational-Wave Observatory) and its sister experiment, Advanced Virgo, have detected gravitational waves from colliding neutron stars — a cosmic crash also observed by more than 70 observatories around the world. H. THOMPSON/SCIENCE NEWS/YOUTUBE

Editor's note: This story will be updated throughout the day as more information becomes available.

 

It was very good, honest

 

What detecting gravitational waves means for the expansion of the universe
Speed of spacetime ripples rules out some alternatives to dark energy
BY
LISA GROSSMAN
5:34PM, OCTOBER 24, 2017

please log in to view this image

BANG, FLASH Light waves and gravitational waves from a pair of colliding neutron stars reached Earth at almost the same time, ruling out theories about the universe based on predictions that the two kinds of waves might travel at different speeds.

ILLUSTRATION BY ROBIN DIENEL COURTESY OF THE CARNEGIE INSTITUTION FOR SCIENCE

• Email
• Twitter
• Facebook
• Reddit
• Google+

SPONSOR MESSAGE
Ripples in spacetime travel at the speed of light. That fact, confirmed by the recent detection of a pair of colliding stellar corpses, kills a whole category of theories that mess with the laws of gravity to explain why the universe is expanding as fast as it is.

On October 16, physicists announced that the Advanced Laser Interferometer Gravitational-Wave Observatory, LIGO, had detected gravitational waves from a neutron star merger (SN Online: 10/16/17). Also, the neutron stars emitted high-energy light shortly after merging. The Fermi space telescope spotted that light coming from the same region of the sky 1.7 seconds after the gravitational wave detection. That observation showed for the first time that gravitational waves, the shivers in spacetime set off when massive bodies move, travel at the speed of light to within a tenth of a trillionth of a percent.

Within a day, five papers were posted at arXiv.org mourning hundreds of expanding universe theories that predicted gravitational waves should travel faster than light — an impossibility without changes to Einstein’s laws of gravity. These theories “are very, very dead,” says the coauthor of one of the papers, cosmologist Miguel Zumalacárregui of the Nordic Institute for Theoretical Physics, or NORDITA, in Stockholm. “We need to go back to our blackboards and start thinking of other alternatives.”

In the 1990s, observations of exploding stars showed that more distant explosions were dimmer than existing theories predicted. That suggested that the universe is expanding at an ever-increasing rate (SN: 10/22/11, p. 13). Cosmologists have struggled ever since to explain why.

The most popular explanation for the speedup is that spacetime is filled with a peculiar entity dubbed dark energy. “You can think of it like a mysterious fluid that pushes everything apart and counteracts gravity,” says cosmologist Jeremy Sakstein of the University of Pennsylvania, coauthor of another new paper.

Story continues after image

please log in to view this image

EVER-GROWING The universe has been expanding since the Big Bang, but its expansion rate is unexpectedly speeding up. The simultaneous observation of light and gravitational waves from colliding neutron stars just killed a whole swath of possible reasons why.
NASA


In the simplest version of this theory, the density of this dark energy has not changed over the history of the universe, so physicists call it a cosmological constant. This doesn’t require any changes to gravity — which is good, because gravity has been well-tested inside the solar system.

The cosmological constant idea matches observations of the wider universe, but it has some theoretical difficulties. Dark energy is about 120 orders of magnitude weaker than theorists calculate it should be (SN Online: 11/18/13), a mismatch that makes scientists uncomfortable.

Also, different methods for measuring the rate of expansion come up with slightly different numbers (SN: 8/6/16, p. 10). Measurements based on exploding stars suggest that distant galaxies are speeding away from each other at 73 kilometers per second for each megaparsec (about 3.3 million light-years) of space between them. But observations based on the cosmic microwave background, ancient light that encodes information about the conditions of the early universe, found that the expansion rate is 67 km/s per megaparsec. The disagreement suggests that either one of the measurements is wrong, or the theory behind dark energy needs a tweak.

So instead of invoking a substance to counteract gravity, theorists tried to explain the expanding universe by weakening gravity itself. Any modifications to gravity need to leave the solar system intact. “It’s quite hard to build a theory that accelerates the universe and also doesn’t mess up the solar system,” says cosmologist Tessa Baker of the University of Oxford, coauthor of still another paper.

These theories take hundreds of forms. “This field of modified gravity theories is a zoo,” says Baker. Some suggest that gravity leaks out into extra dimensions of space and time. Many others account for the universe’s speedy spreading by adding a different mysterious entity — some unknown particle perhaps — that drains gravity’s strength as the universe evolves.

But the new entity would have another crucial effect: It could slow the speed of light waves, similar to the way light travels more slowly through water than through air. That means that the best alternatives to dark energy required gravitational waves to travel faster than light — which they don’t.

Justin Khoury, a theoretical physicist at the University of Pennsylvania who has worked on several of the alternative gravity theories but was not involved in the new papers, was surprised that one gravitational-wave observation ruled out so many theories at once. He’s hardly disappointed, though.

“The fact that we’re learning something about dark energy because of this measurement is incredibly exciting,” he says.

Observing gravitational waves and light waves at the same time offers a third, independent way to measure how fast the universe is expanding. For now, that rate lies frustratingly right between the two clashing measurements scientists already had, at 70 km/s per megaparsec. But it’s still imprecise. Once LIGO and other observatories have seen 10 or 20 more neutron star collisions, researchers should be able to tell which measurement is correct and figure out whether dark energy needs an update, Zumalacárregui says.

“Gravitational waves may kill these models, but eventually they have the potential to tell us if this discrepancy is for real,” he says. “That’s something that is in itself very beautiful.”

 

Godspeed Dick Gordon, CMP on Apollo12 and pilot of Gemini XI

https://www.nytimes.com/2017/11/07/...n-gemini-and-apollo-astronaut-dies-at-88.html

Sisu would say that the Van Allen Belts finally got him.

 

The right stuff RIP.

 

Sisu would say he never went up - it's all a big lie.

Did you see a programme about the Soviet side of the early space race, on a couple of nights ago?