Tuesday, July 21, 2020

JULIAN ASSANGE




Pro-Transparency Group Leaks New Files on the Case Between the U.S. Government and Julian Assange

By Sarah Basford on  at 
The pro-transparency group, DDoSecrets, has published sensitive documents and communications relating to the case between Julian Assange and the U.S. Government on a site called AssangeLeaks.
The documents were published on AssangeLeaks, at 3am AEST on July 15 and contain 26 PDFs as well as a video file and a folder of previous leaked documents. Prior to publishing the group had a countdown timer running on the site.
The subject of the release contains a number of chat logs between Julian Assange, the Australian founder of WikiLeaks. The documents included on the site include chat logs and letters dating back to 2010 between Assange, sources and hackers. They relate to Chelsea Manning and upcoming leaks the organisation had planned at the time.
The site said it was not taking a side by releasing the information, rather that the release of documents was in the interest of transparency.
“With the [U.S.] Justice Department’s superseding indictment against Assange, public access to the evidence becomes critical. The documents in this file illuminate that case and illustrate how WikiLeaks operates behind closed doors,” the site reads.
“AssangeLeaks is not for or against Julian Assange or WikiLeaks, and is only interested in the evidence.”
The documents’ publication hasn’t been without criticism. An Italian investigative reporter and pro-Assange advocate, Stefania Maurizi stated that private communications between journalists should not be the target of document releases unless there is criminal wrongdoing.
Assange is currently serving a 50-week sentence in London’s HM Prison Belmarsh for “failing to surrender to the court”. He was previously granted asylum by London’s Ecuadorean embassy and had lived there since 2012 until his arrest in April 2019.
In May 2019, 17 new charges were filed by the U.S. government against Assange, accusing him and WikiLeaks of violating the U.S.’s Espionage Act.
“To obtain information to release on the WikiLeaks website, Assange encouraged sources to circumvent legal safeguards on information; provide that protected information to WikiLeaks for public dissemination; and continue the pattern of illegally procuring and providing protected information to WikiLeaksfor distribution to the public,” the charges read.
“He predicated his and WikiLeaks’s success in part upon encouraging sources with access to such information to violate legal obligations and provide that information for WikiLeaks to disclose.”
Earlier this month, the Justice Department filed a superseding indictment — a new set of charges that supersedes the previous ones — broadening the charges against Assange.
It alleges Assange had worked with hacking groups, like Anonymous and LulzSec, to target classified government information. It alleges it was has this information after revealing a member of LulzSec, referenced as “Sabu”, was an informant for the Federal Bureau of Investigation (FBI).
Assange’s extradition hearing in London is expected to occur in September after a delay pushed its original May date back.
Correction (July 17, 2020): An earlier version of this article referred to DDoSecrets as a group of hacktivists. This is incorrect and the article has been updated to reflect this. Gizmodo regrets this error.

Online documentary exposes the psychological torture of Julian Assange
By Oscar Grenfell
15 July 2020

Last night, the “Don’t Extradite Assange” group held an online premiere of “Not in our name,” a short documentary reviewing the medical consequences of the decade-long persecution of Julian Assange and its implications for democratic rights globally.

The event was part of the ongoing campaign against the imprisonment of the WikiLeaks founder in Britain’s maximum-security Belmarsh Prison, where he continues to be imperilled by the coronavirus pandemic. It was held in the lead-up to scheduled September hearings for Assange’s extradition to the US, where he faces life imprisonment for exposing American war crimes.

The documentary, directed by John Furse, makes able use of archival footage and original interviews to present a concise and irrefutable summation of the abuses Assange has suffered at the hands of multiple governments, and the basic issues at stake, including press freedom and the struggle against imperialist war.


Unlike many treatments of the Assange case in the corporate media, “Not in our name” places the WikiLeaks founder’s plight firmly in the context of the publications for which Assange faces charges in the US.

It begins with a brief review of the media organisation’s 2010 releases, which revealed mass civilian killings in Iraq and Afghanistan and other violations of international law.

Footage from the time demonstrates the hysterical response of the US military-intelligence and political establishment.

Kenneth Weinstein, president of the Hudson Institute, a neo-conservative think-tank, is shown declaring that it was “very important for our government” to display “no patience for the kind of so-called whistleblowing activities of traitors.”

At a 2010 media appearance, Assange reveals that the US government had demanded that WikiLeaks “destroy our archives relating to the Pentagon and stop dealing with US military whistleblowers,” or “be coerced.”

Emails between leading personnel at Stratfor, a security company with close ties to the CIA, had outlined a plan to “Move him [Assange] from country to country to face various charges for the next 25 years,” culminating in his imprisonment alongside terrorists in a super-max US facility.

Very rapidly, Assange was embroiled in the British legal system on the basis of bogus Swedish allegations of sexual misconduct, which were intended as a backdoor to dispatch him to the US. This compelled the WikiLeaks founder to seek political asylum in Ecuador’s London embassy in 2012.

The bulk of the documentary is an elaboration of UN Special Rapporteur Nils Melzer’s finding that Assange displays medically-verifiable symptoms of psychological torture as a result of his protracted persecution. This assessment is based on a consultation Melzer and two medical experts held with Assange at Belmarsh Prison in May, 2019, and on the UN official’s extensive study of the legal abuses inflicted on the WikiLeaks founder.

The film outlines several features of the UN’s definition of psychological torture, as they have been displayed in Assange’s treatment:

* Constant fear and anxiety: Assange has faced the prospect of being sent to the US, where he could potentially be subjected to the death penalty, for ten years. Over that period he has been arbitrarily-detained, brutally arrested and held in a maximum-security prison, while senior US government figures have called for his murder.

Australian clinical psychologist Doctor Lissa Johnson told viewers: “Often it is the anticipation of the danger you’re frightened of that is experienced as more traumatic and tormenting than the actual materialisation of that threat.”

* Public vilification: In his initial findings, Melzer stated that Assange had been the victim of an unprecedented campaign of “public mobbing,” involving innumerable slanders from governments and corporate media outlets.

Doctor Derek Summerfield, a leading retired psychologist, explained that this served to “isolate a person further from their sense of who they are and what they’re all about, and to smear their name in such a way as to make it easier to do what the state wishes to do with this person.”

Lissa Longstaff, of Women Against Rape, outlined the manner in which the Swedish allegations were the subject of “state manipulation.” They had served, not only as a pretext for the abrogation of Assange’s rights, but also as the foundation of a systematic smear campaign.

* Loss of autonomy: This was particularly evident when the new Ecuadorian government turned against Assange as it established closer relations with the US in 2017. Assange, despite being a political refugee, was constantly spied upon by a private security firm acting on instructions from the CIA, faced the threat of being evicted from the embassy at any moment, and had his communications cut off, thereby further isolating him.

* Helplessness and hopelessness: Johnson noted that the multiple legal abuses inflicted on Assange, including the illegal revocation of his political asylum and his knowledge that he faced biased political and judicial authorities in Britain, had created a situation in which “anything can happen. It’s deeply destabilising. You don’t know how you can defend yourself, you don’t know what to expect next.”

This had been intensified since Assange’s arrest in April, 2019. He had been denied adequate medical care in Belmarsh Prison, prevented from participating in his own defence and subjected to a series of British hearings that had the character of show-trials.

* Isolation and sensory deprivation: Through most of his imprisonment by Britain, Assange has been detained in solitary confinement. This has continued, even as he has been held on remand solely to facilitate the US extradition request.
Lissa Johnson speaking in defence of Assange earlier this year (Credit: WSWS)

In summing up the consequences, Johnson noted: “We’re designed for short bursts of stress, but when it is constant and relentless, it causes very serious problems with immunity. Immune cells can self-destruct, your body stops producing them, communication in the immune system breaks down. That can render people susceptible to cancer, to atypical infections and renders them very vulnerable to coronavirus.

“These techniques are essentially designed to break someone down so much they don’t want to live, they can’t function.”

Assange’s friend Vaughan Smith recalled that when the WikiLeaks founder called him last Christmas Eve, he had warned that he was “slowly dying” in Belmarsh Prison.

After the screening, Rebecca Vincent, London director of Reporters Sans Frontiéres, hosted a discussion with Melzer and filmmaker John Furse.

Melzer again rejected any suggestion that psychological torture was “torture lite.” He noted that in physical torture, the infliction of violence is a means, not an end in itself. Like psychological torture, its purpose is to “affect and break a person’s mind. You break their body in order to reach their mind.

“The actual target of any act of torture is the mind. It’s always psychological… You can achieve that through physical pain or non-physical pain and suffering. So isolation, combined with humiliation, combined with intimidation, combined with a profound arbitrariness, targets very specifically innate needs of stability, security, orientation and identity... These are confirmed psychological needs that are much closer to our identity than even our body.”

Melzer stated that the vilification of Assange had been aimed at deflecting attention from the state crimes revealed by WikiLeaks. Referring to slanders directed against Assange, he said: “We’re discussing cats and skateboards, but we are not discussing things which have been documented as war crimes.”

Asked about the response to his findings, Melzer said that while governments “grudgingly tolerated” him for now, despite their blithe dismissal of his judgements, he had been told that there would be a “political price to pay” for his exposures.

The UN official noted the way in which international legal norms had been eroded over the previous years: “We have been privatising public service for 40 years, and now we have almost been privatising governments. We have privatised prisons, armies, police, so it’s no wonder governments think they are private.”

Furse also stated that the Assange case had revealed the power of major financial interests, and their undermining of democratic rights.
Nils Melzer addressing a public meeting in London last January

Explaining the broader significance of Assange’s persecution, Melzer declared: “The real purpose of torture, most of the time, is intimidation. And it is not necessarily intimidation of the victim. It’s intimidation of everybody else. That’s why people are tortured in public places, women are raped in the village square in armed conflicts and people are being executed publicly.

“That is what is happening to Julian Assange. It’s not about punishing him [or] interrogating him and finding the truth. It’s about intimidating all other journalists and publishers and making sure that no-one does what he has done, because that’s what states are afraid of.”

Melzer warned “this purpose has already been achieved,” which meant that “this fight is really to re-establish press freedom, rather than just protecting it.”

The event can be viewed in full at Consortium News here.
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Socio-economic status predicts UK boys' development of essential thinking skills

UNIVERSITY OF CAMBRIDGE

A comparison of children in Hong Kong, mainland China and the UK has found that British boys' development of key thinking skills, known as 'executive functions', is unusually reliant on their socio-economic status.
The findings emerged from an ongoing project which is exploring contrasts in the development of these skills in Eastern and Western societies and their relationship to academic achievement. Executive functions are cognitive skills that help us to meet goals - such as our ability to ignore distractions or switch between tasks - and they significantly affect children's performance at school.
Across two linked studies, researchers found that the socio-economic background of British boys is directly connected to these skills. Those from wealthier families typically performed better in tests of their executive functions, while those from less-affluent backgrounds did worse.
The connection was far less direct for British girls, however - and absent altogether among boys or girls from mainland China and Hong Kong, who, despite being generally less affluent than their British peers, consistently outperformed them in the tests.
These results imply that specific cultural factors in children's lives that shape the acquisition of executive functions, also influence socio-economic gaps in academic outcomes. It is not clear what these cultural 'drivers' are, but they may include differences in curriculum, parenting, or attitudes to education.
The research was by a team of academics from the Faculty of Education and the Centre for Family Research, University of Cambridge.
Dr Michelle Ellefson, Reader in Cognitive Science at the Faculty of Education, said: "Based on other research, we might have anticipated a direct link between socio-economic status and executive functions; in fact, this existed only for British boys. Pretty much any test pupils do at school requires executive functions, so if we want to reduce the achievement gap between children from different backgrounds, it's important that we understand the mechanisms behind that relationship."
Claire Hughes, Professor of Developmental Psychology in the Centre for Family Research, said: "There is concern in the UK that among children from less-advantaged backgrounds, boys in particular often under-perform academically, and the possibility has been raised in some research that features of their home environment play a role in this. What is interesting here is that we saw no relationship between socio-economic status and executive functions for boys in Hong Kong and China. We need to investigate why that might be the case."
The research was part of the Family Thinking Skills project, which is exploring links between executive functions, school attainment and cultural differences in Britain and Hong Kong by comparing data from children and parents in both countries. Executive functions are mediated by the brain's prefrontal cortex, which develops into our mid-20s, and this means that they are likely to be shaped in part by cultural influences like upbringing and environment.
The latest pair of studies looked at whether socio-economic status, which is known to influence children's performance at school, does so because it impacts on their executive functions, or has an effect independent of cognitive skills. They also investigated how consistent the relationship is across genders. "Very little research has looked at this in Asia, and big differences with the UK might point to cultural differences driving attainment," Ellefson said.
Initially, the researchers used data from 835 children aged 9 to 16 living in Hong Kong and the UK. The participants completed computer-based thinking games to test their executive functions, and various mathematical tests to assess numeracy. Data about socio-economic status was also provided by their parents and through a survey.
Because children in Hong Kong are highly adept with computers from an extremely young age, which might distort the results in the thinking skills tests, a second study was undertaken with 453 children in Shandong, China, led by PhD researcher Chengyi Xu. This deliberately targeted children whose use computers much less.
Overall, British students performed significantly worse in the numeracy tests, and their executive functions were about two years behind the level of their Chinese peers, even though British children tended to be from wealthier backgrounds. Within countries, there was little difference between girls' and boys' average test scores, although girls displayed slightly higher cognitive flexibility.
The children's levels of executive function and socio-economic status were both shown to affect their numeracy scores, but in most cases they did so independently of each other. The exception was British boys, for whom socio-economic status directly predicts executive functions, which in turn affects their numeracy.
The researchers also measured general cognitive skills, beyond executive functions alone. Here, they found that both boys and girls from wealthier backgrounds in the UK tend to have better general cognitive skills than those from less-affluent families, whereas in China and Hong Kong, there was no relationship to socio-economic status.
The data from Shandong also confirmed that computer usage had no effect on the acquisition of executive functions.
The results strongly suggest that cultural distinctions have shaped a gulf between the thinking skills of British and Asian children, with consequences for their relative attainment. More research is needed to establish what these are, but the nature of the school curriculum, teaching styles, parental expectations, or social attitudes to education, may be some of the factors involved.
In addition, the close link between socio-economic background and thinking skills for British boys in particular suggests that understanding more about these cultural drivers may help to narrow the attainment gap within the UK. "A clearer picture of why differences exist in the development of executive functions between children in Britain and Hong Kong would potentially help to inform interventions to reduce that gap," Hughes said.
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Both studies are published in the Journal of Experimental Child Psychology.

Richer UK boys have better thinking skills, study finds

But link between socio-economic status and thinking skills is less direct for British girls, and absent from all pupils in China and Hong Kong

Tes Reporter

computer
British boys from wealthier families typically perform better in tests of their thinking skills than those from less affluent backgrounds, according to research.

But a comparison of children in Hong Kong, mainland China and the UK indicated that the connection between executive functions and socio-economic status was far less direct for British girls, and absent altogether among boys and girls from China and Hong Kong.

Despite being generally less affluent, young people from China and Hong Kong consistently outperformed their British peers in tests.
Executive functions are the mental skills, such as flexible-thinking and self-control, that help people to meet goals.

They are mediated by the brain's prefrontal cortex, which develops into a person's mid-20s.

The research suggests that cultural factors may shape the acquisition of executive functions, but it is not clear what these factors are.

Possibilities include differences in curriculum, parenting or attitudes to education.

The comparison was conducted by a team of academics from the Faculty of Education and the Centre for Family Research at Cambridge University.

Dr Michelle Ellefson, reader in cognitive science at the Faculty of Education, said: "Based on other research, we might have anticipated a direct link between socio-economic status and executive functions; in fact, this existed only for British boys.

"Pretty much any test pupils do at school requires executive functions, so if we want to reduce the achievement gap between children from different backgrounds, it's important that we understand the mechanisms behind that relationship."

Claire Hughes, professor of developmental psychology in the Centre for Family Research, said: "There is concern in the UK that among children from less-advantaged backgrounds, boys in particular often under-perform academically, and the possibility has been raised in some research that features of their home environment play a role in this.

"What is interesting here is that we saw no relationship between socio-economic status and executive functions for boys in Hong Kong and China.

"We need to investigate why that might be the case."

The research was part of the Family Thinking Skills project, which is exploring links between executive functions, school attainment and cultural differences in Britain and Hong Kong by comparing data from children and parents in both countries.

Initially researchers used data from 835 children aged nine to 16 living in Hong Kong and the UK.

Participants completed computer-based thinking games to test their executive functions, and various mathematical tests to assess numeracy.

Data about socio-economic status was also provided by their parents and through a survey.

Because children in Hong Kong are highly adept with computers from an extremely young age, which might distort the results in the thinking skills tests, a second study was undertaken with 453 children in Shandong, China.

This deliberately targeted children whose use computers much less.

Both studies are published in the Journal of Experimental Child Psychology.

Tes Reporter

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Photos may improve understanding of volcanic processes

PENN STATE
 
Volume 90%
 
VIDEO: A TEAM OF PENN STATE RESEARCHERS STUDIED TELICA VOLCANO, A PERSISTENTLY ACTIVE VOLCANO IN WESTERN NICARAGUA, TO BOTH OBSERVE AND QUANTIFY SMALL-SCALE INTRA-CRATER CHANGE ASSOCIATED WITH BACKGROUND AND ERUPTIVE ACTIVITY... view more 
CREDIT: PENN STATE
The shape of volcanoes and their craters provide critical information on their formation and eruptive history. Techniques applied to photographs -- photogrammetry -- show promise and utility in correlating shape change to volcanic background and eruption activity.
Changes in volcano shape -- morphology -- that occur with major eruptions are quantifiable, but background volcanic activity, manifesting as small volume explosions and crater wall collapse, can also cause changes in morphology and are not well quantified.
A team of Penn State researchers studied Telica Volcano, a persistently active volcano in western Nicaragua, to both observe and quantify small-scale intra-crater change associated with background and eruptive activity. Geologists consider Telica 'persistently' active because of its high levels of seismicity and volcanic degassing, and it erupts on less than 10-year time periods.
The team used direct observations of the crater, photographic observations from 1994 to 2017 and photogrammetric techniques on photos collected between 2011 and 2017 to analyze changes at Telica in the context of summit crater formation and eruptive processes. They used structure-from-motion (SfM), a photogrammetric technique, to construct 3D models from 2D images. They also used point cloud differencing, a method used to measure change between photo sampling periods, to compare the 3D models, providing a quantitative measure of change in crater morphology. They reported their results in Geochemistry, Geophysics, Geosystems.
"Photos of the crater were taken as part of a multi-disciplinary study to investigate Telica's persistent activity," said Cassie Hanagan, lead author on the study. "Images were collected from our collaborators to make observations of the crater's features such as the location and number of fumaroles or regions of volcanic degassing in the crater. For time periods that had enough photos, SfM was used to create 3D models of the crater. We could then compare the 3D models between time periods to quantify change."
Using the SfM-derived 3D models and point cloud differencing allowed the team to quantify how the crater changed through time.
"We could see the changes by visually looking at the photos, but by employing SfM, we could quantify how much change had occurred at Telica," said Peter La Femina, associate professor of geosciences in Penn State's Department of Geosciences. "This is one of the first studies to look at changes in crater morphology associated with background and eruptive activity over a relatively long time span, almost a 10-year time period."
Telica's morphological changes were then compared to the timing of eruptive activity to investigate the processes leading to crater formation and eruption.
Volcanoes erupt when pressure builds beyond a breaking point. At Telica, two mechanisms for triggering eruptions have been hypothesized. These are widespread mineralization within the underground hydrothermal system that seals the system and surficial blocking of the vent by landslides and rock fall from the crater walls. Both mechanisms could lead to increases in pressure and then eruption, according to the researchers.
"One question was whether or not covering the vents on the crater floor could cause pressure build up, and if that would cause an explosive release of this pressure if the vent were sufficiently sealed," said Hanagan.
Comparing the point cloud differencing results and the photographic observations indicated that vent infill by mass wasting from the crater walls was not likely a primary mechanism for sealing of the volcanic system prior to eruption.
"We found that material from the crater walls does fall on the crater floor, filling the eruptive vent," said La Femina. "But at the same time, we still see active fumaroles, which are vents in the crater walls where high temperature gases and steam are emitted. The fumaroles remained active even though the talus from the crater walls covered the vents. This suggests that at least the deeper magma-hydrothermal system is not directly sealed by landslides."
The researchers further note that crater wall material collapse is spatially correlated to where degassing is concentrated, and that small eruptions blow out this fallen material from the crater floor. They suggest these changes sustain a crater shape similar to other summit craters that formed by collapse into an evacuated magma chamber.
"What we found is that during the explosions, Telica is throwing out a lot of the material that came from the crater walls," said La Femina. "In the absence of magmatic eruptions, the crater is forming through this background process of crater wall collapse, and the regions of fumarole activity collapse preferentially."
###
The team collaborated with Mel Rogers, assistant research professor at the University of South Florida. Hanagan, now a graduate student at the University of Arizona, completed this research as part of her Schreyer Honors College honors thesis and Department of Geosciences senior thesis.
The National Science Foundation and NASA PA Space Grant WISER program fellowship partially funded this research.
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Plato was right. Earth is made, on average, of cubes

The ancient Greek philosopher was on to something, researchers found
UNIVERSITY OF PENNSYLVANIA
IMAGE
IMAGE: THE RESEARCH TEAM MEASURED AND ANALYZED FRAGMENTATION PATTERNS OF ROCKS THEY COLLECTED AS WELL AS FROM PREVIOUSLY ASSEMBLED DATASETS. view more 
CREDIT: COURTESY OF GABLOR DOMOKOS AND DOUGLAS JEROLMACK
Plato, the Greek philosopher who lived in the 5th century B.C.E., believed that the universe was made of five types of matter: earth, air, fire, water, and cosmos. Each was described with a particular geometry, a platonic shape. For earth, that shape was the cube.
Science has steadily moved beyond Plato's conjectures, looking instead to the atom as the building block of the universe. Yet Plato seems to have been onto something, researchers have found.
In a new paper in the Proceedings of the National Academy of Sciences, a team from the University of Pennsylvania, Budapest University of Technology and Economics, and University of Debrecen uses math, geology, and physics to demonstrate that the average shape of rocks on Earth is a cube.
"Plato is widely recognized as the first person to develop the concept of an atom, the idea that matter is composed of some indivisible component at the smallest scale," says Douglas Jerolmack, a geophysicist in Penn's School of Arts & Sciences' Department of Earth and Environmental Science and the School of Engineering and Applied Science's Department of Mechanical Engineering and Applied Mechanics. "But that understanding was only conceptual; nothing about our modern understanding of atoms derives from what Plato told us.
"The interesting thing here is that what we find with rock, or earth, is that there is more than a conceptual lineage back to Plato. It turns out that Plato's conception about the element earth being made up of cubes is, literally, the statistical average model for real earth. And that is just mind-blowing."
The group's finding began with geometric models developed by mathematician Gábor Domokos of the Budapest University of Technology and Economics, whose work predicted that natural rocks would fragment into cubic shapes.
"This paper is the result of three years of serious thinking and work, but it comes back to one core idea," says Domokos. "If you take a three-dimensional polyhedral shape, slice it randomly into two fragments and then slice these fragments again and again, you get a vast number of different polyhedral shapes. But in an average sense, the resulting shape of the fragments is a cube."
Domokos pulled two Hungarian theoretical physicists into the loop: Ferenc Kun, an expert on fragmentation, and János Török, an expert on statistical and computational models. After discussing the potential of the discovery, Jerolmack says, the Hungarian researchers took their finding to Jerolmack to work together on the geophysical questions; in other words, "How does nature let this happen?"
"When we took this to Doug, he said, 'This is either a mistake, or this is big,'" Domokos recalls. "We worked backward to understand the physics that results in these shapes."
Fundamentally, the question they answered is what shapes are created when rocks break into pieces. Remarkably, they found that the core mathematical conjecture unites geological processes not only on Earth but around the solar system as well.
"Fragmentation is this ubiquitous process that is grinding down planetary materials," Jerolmack says. "The solar system is littered with ice and rocks that are ceaselessly smashing apart. This work gives us a signature of that process that we've never seen before."
Part of this understanding is that the components that break out of a formerly solid object must fit together without any gaps, like a dropped dish on the verge of breaking. As it turns out, the only one of the so-called platonic forms--polyhedra with sides of equal length--that fit together without gaps are cubes.
"One thing we've speculated in our group is that, quite possibly Plato looked at a rock outcrop and after processing or analyzing the image subconsciously in his mind, he conjectured that the average shape is something like a cube," Jerolmack says.
"Plato was very sensitive to geometry," Domokos adds. According to lore, the phrase "Let no one ignorant of geometry enter" was engraved at the door to Plato's Academy. "His intuitions, backed by his broad thinking about science, may have led him to this idea about cubes," says Domokos.
To test whether their mathematical models held true in nature, the team measured a wide variety of rocks, hundreds that they collected and thousands more from previously collected datasets. No matter whether the rocks had naturally weathered from a large outcropping or been dynamited out by humans, the team found a good fit to the cubic average.
However, special rock formations exist that appear to break the cubic "rule." The Giant's Causeway in Northern Ireland, with its soaring vertical columns, is one example, formed by the unusual process of cooling basalt. These formations, though rare, are still encompassed by the team's mathematical conception of fragmentation; they are just explained by out-of-the-ordinary processes at work.
"The world is a messy place," says Jerolmack. "Nine times out of 10, if a rock gets pulled apart or squeezed or sheared--and usually these forces are happening together--you end up with fragments which are, on average, cubic shapes. It's only if you have a very special stress condition that you get something else. The earth just doesn't do this often."
The researchers also explored fragmentation in two dimensions, or on thin surfaces that function as two-dimensional shapes, with a depth that is significantly smaller than the width and length. There, the fracture patterns are different, though the central concept of splitting polygons and arriving at predictable average shapes still holds.
"It turns out in two dimensions you're about equally likely to get either a rectangle or a hexagon in nature," Jerolmack says. "They're not true hexagons, but they're the statistical equivalent in a geometric sense. You can think of it like paint cracking; a force is acting to pull the paint apart equally from different sides, creating a hexagonal shape when it cracks."
In nature, examples of these two-dimensional fracture patterns can be found in ice sheets, drying mud, or even the earth's crust, the depth of which is far outstripped by its lateral extent, allowing it to function as a de facto two-dimensional material. It was previously known that the earth's crust fractured in this way, but the group's observations support the idea that the fragmentation pattern results from plate tectonics.
Identifying these patterns in rock may help in predicting phenomenon such as rock fall hazards or the likelihood and location of fluid flows, such as oil or water, in rocks.
For the researchers, finding what appears to be a fundamental rule of nature emerging from millennia-old insights has been an intense but satisfying experience.
"There are a lot of sand grains, pebbles, and asteroids out there, and all of them evolve by chipping in a universal manner," says Domokos, who is also co-inventor of the Gömböc, the first known convex shape with the minimal number--just two--of static balance points. Chipping by collisions gradually eliminates balance points, but shapes stop short of becoming a Gömböc; the latter appears as an unattainable end point of this natural process.
The current result shows that the starting point may be a similarly iconic geometric shape: the cube with its 26 balance points. "The fact that pure geometry provides these brackets for a ubiquitous natural process, gives me happiness," he says.
"When you pick up a rock in nature, it's not a perfect cube, but each one is a kind of statistical shadow of a cube," adds Jerolmack. "It calls to mind Plato's allegory of the cave. He posited an idealized form that was essential for understanding the universe, but all we see are distorted shadows of that perfect form."
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Douglas Jerolmack is a professor in the Department of Earth and Environmental Science in the School of Arts & Sciences and the School of Engineering and Applied Science's Department of Mechanical Engineering and Applied Mechanics at the University of Pennsylvania.
Gábor Domokos is a professor and director of the MTA-BME Morphodynamics Research Group at the Budapest University of Technology and Economics.
Ferenc Kun is a professor in the Department of Theoretical Physics at the University of Debrecen.
János Török is an associate professor in the Department of Theoretical Physics at the Budapest University of Technology and Economics.
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