An artist's impression of SN 2006gyM, one of the brightest supernovas ever recorded. Photo: Weiss/NASA/CXC/Getty
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“Supernova in a bottle” will help create matter from light

The new process could provide a clean way of doing particle physics experiments.

In 1934, two physicists came up with a theory that described how to create matter from pure light. But they dismissed the idea of ever observing such a phenomenon in the laboratory because of the difficulties involved setting up such an experiment.

Now, Oliver Pike of Imperial College London and his colleagues have found a way to achieve this dream, 80 years after US physicists Gregory Breit and John Wheeler explained the theory. This group hopes to use high-energy lasers aimed at a specially designed gold vessel to convert photons into matter-antimatter particle pairs, recreating what happens in some exceptional stellar explosions.

Pike, who led the research published in the journal Nature Photonics, said, “The idea is that light goes in and matter comes out.” To be sure, the matter created won’t be every day-objects; instead the process will produce sub-atomic particles.

“To start with, the matter will consist of electrons and its antimatter equivalent positrons,” Pike said. “But with higher energy input in the lasers, we should be able to create heavier particles.”

Pike concedes this won’t be the first time light has been converted into matter. In 1997, US researchers at the Stanford Linear Accelerator Centre (SLAC) were able to do so, albeit in a different way.

The SLAC experiment used electrons to first create high-energy light particles, which then underwent multiple collisions to produce electrons and positrons, all within same chamber. This is called the multi-photon Breit-Wheeler process, named after the two physicists who came up with the theory in 1934.

“The key difference in the SLAC experiment and the one we propose is that our process will be more straightforward,” Pike said. In the new proposal, the laser beam will still be generated using free electrons, but it will be separated from the electrons.

Why create light using matter and then convert it back? Apart from showing that the Breit-Wheeler process can happen without the multiple photons the SLAC experiment needed, Pike thinks their process provides a clean way of doing particle physics experiments.

Current particle-physics experiments involve smashing sub-atomic particles at great speeds and sorting through the mess of new particles that are created in the explosion. This is how the Higgs boson was found in the Large Hadron Collider.

The new experimental design will be similar. Rather than involving a complicated mix of particles and photons, the laser beam will be sent into a small gold hohlraum (German for “empty room”). There, individual photons can interact with the radiation field that’s generated when the hohlraum is excited by a laser, creating the electron-positron pairs.

“While physicists have excellent methods to sift through such data, our process has the advantage that it will be easier to analyse,” Pike said. “Light will go in from one end of the hohlraum and particles created will come out from the other end.”

Pike and colleagues are now working to secure time on high-energy laser beams to carry out the experiment. The two likely candidates are Aldermaston, Berkshire in the UK or Rochester, New York in the US.

Andrei Seryi at the University of Oxford found the work interesting, but warned it is still too far away from being used in particle-physics experiments. “Theoretically, however, it would be great if we are able to create particles from only light.”

“With such high energy lasers, we may not need to build big particle colliders, such as the Large Hadron Collider, which is a 22km underground tunnel,” Seryi said.

Even if we do manage to create a photon collider, we would only be catching up with the natural world, where a specific type of supernova, called “pair instability,” involves the creation of proton-antiproton pairs. If Pike is able to achieve this phenomenon, he will essentially be creating a supernova in a bottle.

The ConversationThis article was originally published on The Conversation. Read the original article.

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The Fake Kids of Instagram? Behind the backlash against the internet famous

Bloggers and vloggers are coming under fire for seeming inauthentic online. 

When beauty blogger Amelia Liana went to the Taj Mahal, there wasn’t another tourist in sight. The ivory-white world heritage site was deserted of all but Liana and a flock of swooping white birds overhead. Liana stood in front of the long reflecting pool that stretches out from the iconic building and stared off into the distance. It was a rare and beautiful moment of solitude at one of the seven wonders of the world.

At least, according to Liana’s Instagram.

As a blogger and YouTuber, Liana is no stranger to online hate. Yet over the last month, social media has been ablaze with individuals accusing Liana of Photoshopping, editing, and faking her pictures. In particular, critics claim she is cutting out pictures of herself and pasting them onto separate pictures of locations and landmarks. Some claim she edited out the tourists in her Taj Mahal picture, while others allege she Photoshopped herself on to a picture of the site.

Liana has released video footage showing that she attended the locations in question, but her critics are not convinced that her corresponding Instagram pictures are entirely authentic.

 A still from Liana's video of her India trip

In one example, lifestyle blogger and masters student Ellie Dickinson, 22, claimed Liana had Photoshopped a picture of an ice-cream in New York City. In the picture, Liana holds up a specialist ice-cream cone from Taiyaki, a shop that Dickinson claims is a twenty minute drive from the street in Liana’s picture. To her, it appears as if Liana took a picture of her ice-cream in one location and then edited it onto another, creating a composite to two images.

These criticisms of Liana's Instagrams are not isolated. She has also been accused of Photoshopping a fake sunset into a plane window and, in one bizarre example, editing a photograph taken at Heathrow Terminal 5 so that the background features planes in Heathrow Terminal 2. In the most questioned photograph, Liana appears to have Photoshopped her bed so it is in front of a picturesque London view. It is hard to prove or disprove which of Liana's photos are faked (or indeed whether any are), though many online are sharing the accusations.

“Because I work with Photoshop a lot, I zoomed in on one of her pictures because the grain and sharpness didn't seem right and went from there,” explains Dickinson, who says she thought this incident was “the icing on top of the cake” of blogger and Instagram fakery. Dickinson didn't intend for hate to be sent Liana's way, but urges people to be more questioning of what they see online. 

“Instagram is always a slightly fictionalised image of our lives but too many people believe it's the reality," she says. In her opinion: “We all adjust contrast and lighting but she's taken it a step too far.” 

Fakery on Instagram is nothing new. In May, the Instagrammer and Photographer Sara Melotti told me about the “Instagram mafia”, explaining that many travel bloggers visit the same spot to get the perfect photo, but then leave without touring the area. In October 2015, Instagram model Essena O’Neill quit the site, branding social media “contrived” and rewriting the captions on her images to explain how long it took to take a photo, or whether she was paid by a brand to pose with a product.

Yet the accusations against Liana seem to be more extreme. Though the star has video footage illustrating she really did visit the locations on her Instagram, editing pictures is a grey area. “I keep wondering how you are the only one in shot! It's always so busy there,” reads a comment on Liana’s photograph of the Cattedrale di Santa Maria del Fiore in Florence.

Things become more problematic when money is involved as Liana – like many Instagrammers and vloggers – is often paid by brands to advertise products on her social media. In the much-maligned London bed photograph, Liana is advertising the beauty brand Glam Glow. “Got the Glam Glow setter right after I saw it in your last Video - so far I love it! This picture totally blows my mind!! ❤” wrote one commenter. In many of her posts, Liana references hotels she is staying in, which could in turn influence her followers' booking decisions.

“I think the problem of dramatically engineering Photoshopped Instagram posts is that it encourages an unobtainable lifestyle,” says Laura, a 24-year-old beauty blogger who mocked Liana’s posts on Twitter when the fakery accusations emerged. Laura does not believe Liana should be “attacked” for Photoshopping, but does worry about the trend for fakery in the industry.

“Instagram, by nature, encourages us to post a filtered image focusing on the highlights of our life but there's a difference when Instagrammers choose to create a fantasy and pass that off as reality. When you factor in money and young influential fans as well, I think such a level of delusion edges towards being fraudulent.”

Last week, the YouTuber Lele Pons was accused of lying in an Instagram post in which she claimed to have cut off her hair to donate to charity. Emily Cutshall, a 17-year-old high school student from California discovered that in the picture, Pons was actually holding up hair extensions, passing them off as her real hair. She tweeted her discovery and gained over 76,000 retweets.

“I felt like I needed to get the word out,” explains Cutshall, who says she was “upset” that the star could mislead followers about contributing to a good cause. “The fact that Lele had lied about her donation was not something that I thought she should get away with.”

Since going viral, Cutshall has used her Twitter presence to encourage others to donate their hair. Though she felt guilty about directing negative attention to Pons, she believes it is important that more people “stand up for what [they] believe in and question the integrity of others”.

“If you see someone being dishonest about something you think is important, whether it's an internet personality or a stranger you met five minutes ago, you shouldn't be afraid to take a stand against that,” she says. Lele Pons later tweeted that she had intended to donate her hair before realising wig charities don’t accept dyed hair, but she did not explain why the hair in her photograph appears to be extensions.

The drama around Pons and Liana is part of a wider trend of “exposing” celebrities – both from social and traditional media. In 2016 #TaylorSwiftIsOverParty trended after her ex, Calvin Harris, ranted about her orchestrating media stories. Yet though the trend of “sipping tea” (that is, sharing rumours and enjoying gossip) can make exposing internet celebrities seem flippant, it is important to call out online fakery. Though a Photoshopped sunset is not as damaging as the “fake news” spread during and since the United States Presidential Election, it is still a worrying aspect of the erosion of authenticity online.

 

Headed to my favourite city today with @yslbeauty So excited to be back! #MonParis #Paris #TourEiffel

A post shared by Amelia Liana (@amelialiana) on

Amelia Liana did not respond to a request for comment and nor did her agency. Since 2015, she has been open and transparent about the fact she adds filters and changes the contrast to “play with” her pictures and make them appear more pink, but she has never confirmed the allegations of copying and pasting photographs of herself onto different backgrounds, nor adding in fake elements. It is hard to say with absolute certainty that her pictures are indeed faked, but the backlash demonstrates a thirst for reality and authenticity in an online world of posing and filters. 

In many recent captions on her Instagram photos, Liana has now taken to stating she visits popular attractions at 6 or 7am to get pictures without tourists in the background. In recent pictures, the birds that so frequently flew across the landscape in her old photographs are nowhere to be seen.

Amelia Tait is a technology and digital culture writer at the New Statesman.

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