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In 1951, physicist Julian Schwinger theorized that by applying a uniform electrical field to a vacuum, electron-positron pairs would be spontaneously created out of nothing, through a phenomenon called quantum tunnelling.

The problem with turning the matter-out-of-nowhere theory into Star Trek replicators or transporters? Enormously high electric fields would be required—far beyond the limits of any direct physical experiments.

As a result, the aptly named Schwinger effect has never been seen.

Now theoretical physicists at the University of British Columbia (UBC) have described a parallel effect in a more manageable system. In their model, they substitute a thin film of superfluid helium for the vacuum, and the background flow of the superfluid for the massive electrical field.

“Superfluid Helium-4 is a wonder. At a few atomic layers thick it can be cooled very easily to a temperature where it’s basically in a frictionless vacuum state,” explains Dr. Philip Stamp, a theorist at UBC working on condensed matter and quantum gravity, and author of the new findings published today in PNAS.

“When we make that frictionless vacuum flow, instead of electron-positron pairs appearing, vortex/anti-vortex pairs will appear spontaneously, spinning in opposite directions to one another.”

In the paper, Dr. Stamp and UBC colleague Michael Desrochers outline the theory and the mathematics behind it—mapping out a detailed approach to conducting a direct experiment.

Vacuum tunneling is a process of keen interest in quantum mechanics and quantum field theory. In quantum theory, vacuums aren’t empty, they’re filled with fluctuating fields that can lead to the temporary appearance and disappearance of virtual particles.

“We believe the Helium-4 film provides a nice analog to several cosmic phenomena,” adds Dr. Stamp. “The vacuum in deep space, quantum black holes, even the very beginning of the Universe itself. And these are phenomena we can’t ever approach in any direct experimental way.”

However, Dr. Stamp emphasizes that the real interest of the work may lie less in an analogs – which always have limitations – and more in the way it alters our understanding of superfluids, and of phase transitions in two-dimensional systems.

“These are real physical systems in their own right, not analogs. And we can do experiments on these.”

At the mathematical level, the researchers needed several breakthroughs to make the theory work. For example, previous researchers looking at vortices in superfluids have treated the vortex mass as an unchanging constant. Dr. Stamp and Desrochers showed that this mass will vary dramatically as the vortices move, fundamentally changing our understanding of vortices in both fluids and the early universe.

“It’s exciting to understand how and why the mass varies, and how this affects our understanding of quantum tunnelling processes, which are ubiquitous in physics, chemistry and biology,” says Desrochers.

Stamp also argues that the same mass variability will occur with electron-positron pairs in the Schwinger effect, thence modifying Schwinger’s theory, in a kind of ‘revenge of the analog’.

The work was supported by the National Science and Engineering Research Council.

Severed arms and brutalized skeletal remains recovered from pits at two 6,000-year-old archaeological sites in northeastern France suggest the region’s inhabitants turned torture into a public spectacle to celebrate their victories.

A study on the remains offers evidence that the severed upper arms may have been taken as war trophies, while the excessively mutilated bodies were savagely slaughtered in a ritualized ceremony meant to dehumanize the enemy.

Describing the brutality to Owen Jarus at Live Science, archaeologist Teresa Fernández-Crespo from the University of Valladolid in Spain explains the “lower limbs were [fractured] in order to prevent the victims from escaping, the entire body shows blunt force traumas and, what it is more, in some skeletons there are some marks – piercing holes – that may indicate that the bodies were placed on a structure for public exposure after being tortured and killed.”

These excessively violent killings may have been performed in full public view in a central community space, as a structured, ritualized form of ancient war propaganda to humiliate the enemy while strengthening social unity among the victors.

Related: Human Bones Reveal Evidence of One Horrifying Cannibalistic Feast

A total of 14 skeletons and a number of upper left limbs were recovered from two pits at Achenheim and Bergheim, which are located in Alsace, northeastern France. Dated to the late Middle Neolithic around 4300 to 4150 BCE, they lived during a period that saw an influx of migrants, invaders, and raiders from the greater Paris Basin, sparking wars of conquest among disparate tribes.

To trace the origins of both the slaughterers and the slaughtered, the researchers performed a multi-isotope analysis on a selection of the teeth and bones, using signature ratios of lighter and heavier versions of key elements to infer the origins, diet, and social rankings of the dead.

The researchers analyzed the remains of 82 humans, including the pits’ “victims” and individuals from the region termed “non-victims”, who were found in traditional burials. The researchers also analyzed remains from 53 animals and 35 modern plants to establish a regional baseline.

The analysis revealed that the severed arms belonged to members of nearby invading groups, and may have been taken by locals as war trophies.

While war trophies aren’t uncommon in martial history, an upper arm appears to be a rare choice, with heads and hands more typical prizes found in the record. The severed upper arms may have even been “preserved [by being] smoked, dried, or embalmed” to be shown off for an extended time, the researchers claim.

In contrast, the whole skeletons belonged to individuals from a different place, possibly southern Alsace, suggesting they were captives that were brought back to the village, tortured, and then executed. They may have been deposited into the pits (along with the severed arms) during a closing ceremony to signal triumph, revenge, and the restoration of honor for allies fallen or injured in battle.

As an alternative hypothesis, based on evidence from Indigenous North American communities, all the victims may have been captured alive. Those who survived the mutilations may have “been retained as slaves or even adopted” by families who suffered casualties during the conflict, the authors propose.

“It may not be coincidental that in both sites severed upper limbs show isotope values consistent with northern Alsace and most skeletons of killed individuals with southern Alsace, which, if actually translated to different identities, might supply a reason for the differential treatment of captives,” the researchers state.

Additionally, the ritualized killings may have been a votive offering meant to appease the ancestors or ‘gods’ who aided the victors in their conquest.

“These findings speak to a deeply embedded social practice – one that used violence not just as warfare, but as spectacle, memory, and assertion of dominance,” says archaeologist and study co-author Rick Schulting, of Oxford’s School of Archaeology.

In the grander scheme of history, this was a pyrrhic victory. The brutalizers then became the brutalized and supplanted by another group of people, as so often happens.

This research is published in Science Advances.

Severed arms and brutalized skeletal remains recovered from pits at two 6,000-year-old archaeological sites in northeastern France suggest the region’s inhabitants turned torture into a public spectacle to celebrate their victories.

A study on the remains offers evidence that the severed upper arms may have been taken as war trophies, while the excessively mutilated bodies were savagely slaughtered in a ritualized ceremony meant to dehumanize the enemy.

Describing the brutality to Owen Jarus at Live Science, archaeologist Teresa Fernández-Crespo from the University of Valladolid in Spain explains the “lower limbs were [fractured] in order to prevent the victims from escaping, the entire body shows blunt force traumas and, what it is more, in some skeletons there are some marks – piercing holes – that may indicate that the bodies were placed on a structure for public exposure after being tortured and killed.”

These excessively violent killings may have been performed in full public view in a central community space, as a structured, ritualized form of ancient war propaganda to humiliate the enemy while strengthening social unity among the victors.

Related: Human Bones Reveal Evidence of One Horrifying Cannibalistic Feast

A total of 14 skeletons and a number of upper left limbs were recovered from two pits at Achenheim and Bergheim, which are located in Alsace, northeastern France. Dated to the late Middle Neolithic around 4300 to 4150 BCE, they lived during a period that saw an influx of migrants, invaders, and raiders from the greater Paris Basin, sparking wars of conquest among disparate tribes.

To trace the origins of both the slaughterers and the slaughtered, the researchers performed a multi-isotope analysis on a selection of the teeth and bones, using signature ratios of lighter and heavier versions of key elements to infer the origins, diet, and social rankings of the dead.

The researchers analyzed the remains of 82 humans, including the pits’ “victims” and individuals from the region termed “non-victims”, who were found in traditional burials. The researchers also analyzed remains from 53 animals and 35 modern plants to establish a regional baseline.

The analysis revealed that the severed arms belonged to members of nearby invading groups, and may have been taken by locals as war trophies.

While war trophies aren’t uncommon in martial history, an upper arm appears to be a rare choice, with heads and hands more typical prizes found in the record. The severed upper arms may have even been “preserved [by being] smoked, dried, or embalmed” to be shown off for an extended time, the researchers claim.

In contrast, the whole skeletons belonged to individuals from a different place, possibly southern Alsace, suggesting they were captives that were brought back to the village, tortured, and then executed. They may have been deposited into the pits (along with the severed arms) during a closing ceremony to signal triumph, revenge, and the restoration of honor for allies fallen or injured in battle.

As an alternative hypothesis, based on evidence from Indigenous North American communities, all the victims may have been captured alive. Those who survived the mutilations may have “been retained as slaves or even adopted” by families who suffered casualties during the conflict, the authors propose.

“It may not be coincidental that in both sites severed upper limbs show isotope values consistent with northern Alsace and most skeletons of killed individuals with southern Alsace, which, if actually translated to different identities, might supply a reason for the differential treatment of captives,” the researchers state.

Additionally, the ritualized killings may have been a votive offering meant to appease the ancestors or ‘gods’ who aided the victors in their conquest.

“These findings speak to a deeply embedded social practice – one that used violence not just as warfare, but as spectacle, memory, and assertion of dominance,” says archaeologist and study co-author Rick Schulting, of Oxford’s School of Archaeology.

In the grander scheme of history, this was a pyrrhic victory. The brutalizers then became the brutalized and supplanted by another group of people, as so often happens.

This research is published in Science Advances.

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