Let it rip. Image: Getty Images
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From Big Bang to Big Rip: how will the universe end?

The universe is a very sticky place, but how sticky is it? Could it favour the “Big Rip” demise of the universe?

All good things come to an end. And the universe is no exception. In about 10100 years (that’s 10x10, 100 times over – so a long time), the universe will be dead, and all that will be left is a relic of the life and energy it once birthed.

Aeons from now, the universe will be nothing but bits of dead photons, electrons and neutrinos – that’s about it, sadly.

But how will the universe end? Will it freeze to death (the Big Freeze), get crunched to bits (the Big Crunch), or even more radically, get ripped apart (the Big Rip)?

It is not known how to describe viscous fluids (yep, sticky fluids) in the context of Einstein’s general relativity. Over the years, different approaches have been made, from Eckart’s theory to Mueller-Israel-Stewart theory.

Recently, researchers at Vanderbilt University have discovered a new mathematical formulation that may help draw a line between the two notions. This new formula ties in well with one of the more radical scenarios of how the universe with end – the "Big Rip".

The Big Rip is a cosmological hypothesis first published in 2003, which proposes the possibility of dark energy accelerating, and consequently the universe expanding, without limit. The dark energy will eventually become unbearably strong that the universe (gravitational, electromagnetic and weak nuclear forces) rips itself into pieces, hence the name.

The maths also sheds new light on the fundamental properties of dark energy, a force that is still largely unknown. The new approach is described in the Physical Review D.

Cosmological viscosity (ie. the stickiness of the universe) isn’t like the viscosity of ketchup, for example, which is a measure of a fluid’s resistance to flowing through small openings like the neck of a ketchup bottle. It’s the measure of a fluid’s resistance to expansion or contraction.

Marcelo Disconzi, an assistant professor of  mathematics, started off by tackling the problem of fluid dynamics - the natural science of fluids in motion - which happens quite frequently in the universe from supernovae (exploding stars) to neutron stars (stars double the size of the Sun that have crushed down to the size of cities).

Although scientists have successfully modelled what happens when ideal fluids with no stickiness move to near-light speeds, no one has managed to come up with a generally accepted way of dealing with sticky fluids travelling at near-light speed.

This is because the models haven’t made much sense: the most confusing models predict conditions where these fluids travel faster than the speed of light, defying the laws of physics.

These problems inspired Disconzi to reformulate an old proposal by André Lichnerowic from 1955 (a proposal that remained mostly unnoticed until Disconzi’s 2014 paper) in a way that does not exhibit the flaw of allowing faster-than-light speeds.

After showing that Lichnerowicz's approach is potentially a viable candidate, Disconzi teamed up with Robert Scherrer and Thomas Kephart from the Vanderbilt Physics Department, finding that a Big Rip scenario is a natural consequence of the equations. The results included some potential new insights into the mysterious nature of dark energy.

Most dark energy theories so far haven’t taken cosmic stickiness into consideration, despite the fact that the repulsive effect is strikingly similar to that of dark energy.

“It is possible, but not very likely, that viscosity could account for all the acceleration that has been attributed to dark energy," Disconzi said to Vanderbilt University News‎. "It is more likely that a significant fraction of the acceleration could be due to this more prosaic cause. As a result, viscosity may act as an important constraint on the properties of dark energy,” he adds.

"In previous models with viscosity the Big Rip was not possible," Scherrer said to Vanderbilt University News‎."In this new model, viscosity actually drives the universe toward this extreme end state."

I ask Disconzi about the accuracy of his results. He replies:

My result by no means settles the question of what the correct formulation of relativistic viscous fluids is. What it shows is that, under some assumptions, the equations put forward by Lichnerowicz have solutions and the solutions do not predict faster-than-light signals. But we still don’t know if these results remain valid under the most general situations relevant to physics."

He also reflects on how his new formula may change the way we see cosmology:

It’s too early to tell. What is known from current observational data is that a Big Rip scenario is possible, although the available data is far from conclusive.What our paper brings to the discussion is a mechanism that yields a Big Rip in a fairly natural way, in contrast of most models of the Big Rip where unnatural assumptions have to be introduced."

So the Big Rip idea isn’t so far-fetched after all.

Tosin Thompson writes about science and was the New Statesman's 2015 Wellcome Trust Scholar. 

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Fark.com’s censorship story is a striking insight into Google’s unchecked power

The founder of the community-driven website claims its advertising revenue was cut off for five weeks.

When Microsoft launched its new search engine Bing in 2009, it wasted no time in trying to get the word out. By striking a deal with the producers of the American teen drama Gossip Girl, it made a range of beautiful characters utter the words “Bing it!” in a way that fell clumsily on the audience’s ears. By the early Noughties, “search it” had already been universally replaced by the words “Google it”, a phrase that had become so ubiquitous that anything else sounded odd.

A screenshot from Gossip Girl, via ildarabbit.wordpress.com

Like Hoover and Tupperware before it, Google’s brand name has now become a generic term.

Yet only recently have concerns about Google’s pervasiveness received mainstream attention. Last month, The Observer ran a story about Google’s auto-fill pulling up the suggested question of “Are Jews evil?” and giving hate speech prominence in the first page of search results. Within a day, Google had altered the autocomplete results.

Though the company’s response may seem promising, it is important to remember that Google isn’t just a search engine (Google’s parent company, Alphabet, has too many subdivisions to mention). Google AdSense is an online advertising service that allows many websites to profit from hosting advertisements on its pages, including the New Statesman itself. Yesterday, Drew Curtis, the founder of the internet news aggregator Fark.com, shared a story about his experiences with the service.

Under the headline “Google farked us over”, Curtis wrote:

“This past October we suffered a huge financial hit because Google mistakenly identified an image that was posted in our comments section over half a decade ago as an underage adult image – which is a felony by the way. Our ads were turned off for almost five weeks – completely and totally their mistake – and they refuse to make it right.”

The image was of a fully-clothed actress who was an adult at the time, yet Curtis claims Google flagged it because of “a small pedo bear logo” – a meme used to mock paedophiles online. More troubling than Google’s decision, however, is the difficulty that Curtis had contacting the company and resolving the issue, a process which he claims took five weeks. He wrote:

“During this five week period where our ads were shut off, every single interaction with Google Policy took between one to five days. One example: Google Policy told us they shut our ads off due to an image. Without telling us where it was. When I immediately responded and asked them where it was, the response took three more days.”

Curtis claims that other sites have had these issues but are too afraid of Google to speak out publicly. A Google spokesperson says: "We constantly review publishers for compliance with our AdSense policies and take action in the event of violations. If publishers want to appeal or learn more about actions taken with respect to their account, they can find information at the help centre here.”

Fark.com has lost revenue because of Google’s decision, according to Curtis, who sent out a plea for new subscribers to help it “get back on track”. It is easy to see how a smaller website could have been ruined in a similar scenario.


The offending image, via Fark

Google’s decision was not sinister, and it is obviously important that it tackles things that violate its policies. The lack of transparency around such decisions, and the difficulty getting in touch with Google, are troubling, however, as much of the media relies on the AdSense service to exist.

Even if Google doesn’t actively abuse this power, it is disturbing that it has the means by which to strangle any online publication, and worrying that smaller organisations can have problems getting in contact with it to solve any issues. In light of the recent news about Google's search results, the picture painted becomes more even troubling.

Update, 13/01/17:

Another Google spokesperson got in touch to provide the following statement: “We have an existing set of publisher policies that govern where Google ads may be placed in order to protect users from harmful, misleading or inappropriate content.  We enforce these policies vigorously, and taking action may include suspending ads on their site. Publishers can appeal these actions.”

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