Well-publicized polar geoengineering ideas will not help and could harm, warn experts

Five well-publicized polar geoengineering ideas are highly unlikely to help the polar regions and could harm ecosystems, communities, international relations, and our chances of reaching net zero by 2050.

 

Frontiers

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Five well-publicized polar geoengineering ideas are highly unlikely to help the polar regions and could harm ecosystems, communities, international relations, and our chances of reaching net zero by 2050. 

This is according to a new assessment, published in Frontiers in Science, which looked at five of the most developed geoengineering proposals currently being considered for use in Antarctica and the Arctic. 

The polar regions are home to fragile communities and ecosystems, as well as most of the world’s ice. Technological ‘geoengineering’ approaches have been proposed to delay or address the impacts of climate breakdown in these regions.  

Yet this new review finds that five of those most publicized polar geoengineering ideas are likely to cost billions in set-up and maintenance, while reducing pressure on policymakers and carbon-intensive industries to reduce greenhouse gas emissions. The proposals were also found likely to introduce additional ecological, environmental, legal, and political challenges. 

"These ideas are often well-intentioned, but they‘re flawed. As a community, climate scientists and engineers are doing all we can to reduce the harms of the climate crisis—but deploying any of these five polar projects is likely to work against the polar regions and planet,” said lead author Prof Martin Siegert from University of Exeter. 

"If we instead combine our limited resources towards treating the cause instead of the symptoms, we have a fair shot at reaching net zero and restoring our climate’s health,” said co-author Dr Heidi Sevestre from Arctic Monitoring and Assessment Programme Secretariat. 

The proposals 

To conduct the new assessment, the researchers looked at five geoengineering proposals that have received the most attention to date:  

• stratospheric aerosol injections (SAI): releasing sunlight-reflecting particles such as sulfate aerosols into the atmosphere to reduce the sun’s warming effect 

• sea curtains/walls: flexible, buoyant structures anchored to the seabed to prevent warm water from reaching and melting ice shelves 

• sea ice management: pumping seawater onto sea ice to artificially thicken it, or scattering glass microbeads onto sea ice to boost its reflectivity 

• basal water removal: pumping subglacial water away from underneath glaciers to slow ice sheet flow and reduce ice loss 

• ocean fertilization: adding nutrients such as iron to polar oceans to stimulate blooms of phytoplankton—microscopic creatures that draw carbon into the deep ocean when they die. 

They measured each proposal against their likely scope of implementation, effectiveness, feasibility, potential negative consequences, cost, and existing governance frameworks that would allow timely deployment at scale. They also assessed each proposal’s potential appeal to those vested in avoiding emissions cuts. 

According to the review: 

Effectiveness and feasibility: none of the ideas were found to currently benefit from robust real-world testing. No field experiments were found to exist for sea curtains or sea ice reflection; SAI had only been tested with computer modelling, ocean fertilization experiments were inconclusive, and glacier water removal had not been demonstrated beyond limited drilling.  

The authors note that the polar regions are some of the world’s harshest environments to work in, and even simple logistics are challenging to deploy. They assert that the scale of polar geoengineering would require a human presence in the polar regions unlike anything we have considered to date, and say that many of the ideas do not consider these challenges 

Negative consequences: each of the five ideas were found to risk intrinsic environmental damage, with sea ice management carrying particular ecological risks, such as glass beads darkening the ice, and water pumps requiring vast infrastructure. The authors also found that the risks of SAI include ozone depletion and global climate pattern change; sea curtains risk disrupting habitats, feeding grounds and the migration routes of marine animals including whales, seals and seabirds; glacier water removal risks contaminating subglacial environments with fuels; and ocean fertilization carries uncertainty as to which organisms will flourish or decline, as well as the potential for triggering shifts in natural ocean chemical cycling 

Cost: the authors estimate that each proposal will cost at least $10 billion to set up and maintain. Among the most expensive are sea curtains, projected at $80 billion over 10 years for an 80 km structure. They caution that these costs are likely underestimates, because they are likely to climb higher once knock-on consequences, such as environmental and logistical impacts, are considered 

Governance: the authors found no existing governance frameworks to regulate SAI or sea ice management. Sea curtains and glacier water removal would fall under Antarctic Treaty provisions, while ocean fertilization is treated as marine pollution and restricted under United Nations rules. They caution that each proposal would require extensive political negotiation and the creation of new governance structures and infrastructure 

Scale and timing: the authors conclude that, even if the proposals offered some benefit, none can be deployed at sufficient scale, fast enough, to tackle the climate crisis within the limited time available 

Vested interest appeasement: the authors found that all proposals risk appealing to those seeking to avoid emissions cuts. They note that claims about sea ice management preserving Indigenous Peoples’ rights and environments are misleading, and stress that only rapid decarbonization can achieve this without the introducing additional risks. 

Split resources 

Geoengineering is a divisive topic among experts and affected communities. Some cite large uncertainties in effectiveness, risks of negative consequences, and major legal and regulatory challenges. Others warn against dismissing proof-of-concept research, and argue that geoengineering could buy time while the world cuts emissions. 

Although the authors acknowledge the importance of explorative research, they say that continuing to pursue these five polar geoengineering proposals could shift focus and urgency from the deep systemic change needed to cut greenhouse gas emissions. Geoengineering, they argue, therefore risks splitting monetary and research resources when time is of the essence. 

"Mid-century is approaching, but our time, money, and expertise is split between evidence-backed net zero efforts and speculative geoengineering projects,” said Prof Siegert. “We're hopeful that we can eliminate emissions by 2050, as long as we combine our efforts towards reaching zero emissions." 

"While research can help clarify the potential benefits and pitfalls of geoengineering, it’s crucial not to substitute immediate, evidence-based climate action for as-yet unproven methods. Crucially, these approaches should not distract from the urgent priority of reducing emissions and investing in proven mitigation strategies,” said Dr Sevestre. 

They note that while their assessment focuses on the polar areas, other geoengineering ideas, such as marine cloud brightening and space-based solar reflectors, also need to be assessed against these criteria. 

“The good news is that we have existing goals that we know will work. Global heating will likely stabilize within 20 years of us reaching net zero. Temperatures would stop climbing, offering substantial benefits for the polar regions, the planet, and all lifeforms,” said Prof Siegert. 

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Journal

Frontiers in Science

DOI

10.3389/fsci.2025.1527393 

Method of Research

Systematic review

Subject of Research

Not applicable

Article Title

Safeguarding the polar regions from dangerous geoengineering: a critical assessment of proposed concepts and future prospects

Article Publication Date

9-Sep-2025

 

Racial stereotypes can make us see weapons where they don’t exist

Columbia University

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Unarmed Black civilians are three times more likely to be shot and killed by police officers than unarmed white civilians in the U.S. In tragic cases in recent years, unarmed Black men holding innocuous objects like a wallet, cell phone, or vape pen were killed by police officers because those objects were misidentified as weapons. These split-second fatal mistakes, often under ambiguous and stressful conditions, have sparked urgent debates about their causes and how to fix them.

A new brain-imaging study from researchers at Columbia University suggests that part of the problem is that racial stereotypes can infiltrate the brain’s visual system, prompting us to see objects in ways that conform to these stereotypes. These stereotypes transiently distort how the brain quite literally sees a harmless object. Using functional magnetic resonance imaging (fMRI) and cutting-edge neural decoding techniques, the researchers found that when participants saw everyday graspable objects like a wrench or drill after briefly viewing a Black man’s face, object-processing regions in the brain shifted their neural representation to more closely resemble that of a weapon.

Participants were also asked to sort images, identifying them as either weapons or tools. They consistently showed milliseconds of delay in categorizing tools as tools rather than as weapons when the image was immediately followed by a Black man’s face, indicating an initial unconscious tendency to perceive them as weapons. The researchers then specifically linked this weapon identification bias to the shifts in the brain’s visual system they observed: The more that test subjects’ brains shifted toward a weapon reaction when they saw a tool followed by a Black man’s face, the longer the delay they experienced before successfully resolving the tool as a tool, not a weapon. In some cases, particularly when responding very quickly, subjects made full-blown errors such that tool images followed by a Black man’s face were misidentified as weapons altogether.

The study was led by Jon Freeman, an associate professor of psychology at Columbia, and published in the journal Nature Communications. The other authors, previously in Freeman’s lab group at Columbia, include DongWon Oh, an assistant professor of psychology at National University of Singapore, and Henna Vartiainen, a doctoral candidate at Princeton University.

“Our findings demonstrate that the stereotypes we hold can alter the brain’s visual representation of an object, distorting what we see to fit our biased expectations,” Freeman said.

The findings were robust, replicated across two large and racially diverse samples, and occurred in participants of all racial backgrounds, consistent with the fact that these stereotypes are learned by all members of society. The study included fMRI imaging of 31 subjects from the New York City area, and tested racially biased weapon identification on 422 additional online subjects based around the U.S. The researchers compared study subjects’ reactions to images of Black and white men.

These kinds of racial bias effects on weapon identification have previously been observed in samples of both civilians and police officers, but this is the first brain-imaging study to look into the mechanisms involved. Previous research has linked weapon identification biases with stereotypes that associate Black individuals with crime and danger. Researchers have largely believed that these weapon identification biases do not stem from any visual distortion, instead assuming that people see the object accurately but are then unable to control their racially biased impulses. This new study suggests that an overlooked part of the problem is that stereotypes are creating a temporary visual distortion as well.

By showing that stereotypes can alter perception itself—not just conscious decisions—the findings add a crucial layer to understanding why racially biased mistakes happen in high-stakes contexts like policing.

The work opens the door to new interventions that could target visual perception, which the researchers plan to explore in future research. For instance, repeatedly pairing images of Black men with everyday tools rather than weapons could retrain the visual system, weakening the automatic bias to see a weapon where none exists. Counterintuitively, the opposite may also be true: much like how the eyes adjust after staring into bright light, prolonged exposure to Black-weapon pairings might fatigue the bias itself, allowing neutral objects to be perceived more accurately. The team is planning to explore which possible remedies yield the greatest success.

“We’re eager to build on this research by exploring new interventions that might recalibrate biased visual perceptions,” Freeman said, noting that traditional bias-reduction strategies have fallen short. “Our findings suggest a new direction: targeting not just the stereotypes people hold, but also the visual processes that shape how we see others. If we can change split-second perceptual distortions, we may be able to mitigate these kinds of consequential misjudgments in high-stakes situations under stress and uncertainty.”

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Journal

Nature Communications

DOI

10.1038/s41467-025-63381-7 

Method of Research

Experimental study

Subject of Research

People

Article Title

Racial stereotypes bias the neural representation of objects towards perceived weapons

Article Publication Date

9-Sep-2025

 

First 3D real-time imaging of hydrogen’s effect on stainless steel defects opens the way to a safer hydrogen economy

University of OxfordFacebook

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image: 

An artistic impression of the experiment: 3D rendering of the micro-scale stainless steel grain investigated in this study showing the evolution of defects inside it with time (early – blue lines, later – red lines). The grain is embedded within a polycrystalline bulk sample, as schematically. By focussing a coherent X-ray beam on this grain, a coherent X-ray diffraction pattern can be measured, from which the shape of the grain and the defects inside it can be reconstructed. By continually monitoring this grain while hydrogen is introduced, researchers studied how hydrogen interacts with defects. Credit: David Yang, Felix Hofmann (bubbles graphic sourced from Free PNG Logos, John D.).

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Credit: David Yang, Felix Hofmann (bubbles graphic sourced from Free PNG Logos, John D.).

• A study led by University of Oxford and Brookhaven National Laboratory researchers has uncovered how exposure to hydrogen atoms dynamically alters the internal structure of stainless steel.
• The findings reveal that hydrogen allows internal defects in steel to move in ways not normally possible – which can lead to unexpected failure.
• This discovery offers vital insights that could help make hydrogen fuel systems safer and more reliable, from aircraft and fusion reactors to pipelines and storage tanks.
• The study has been published today (9 Sept) in Advanced Materials.

In a world-first experiment, the team used an advanced X-ray imaging technique to track how tiny defects inside stainless steel (called dislocations) respond to hydrogen exposure. This is crucial to understand how hydrogen can cause metals to weaken or fail, and could guide the design of next-generation alloys for a growing hydrogen economy.

Lead researcher Dr. David Yang (Brookhaven National Laboratory) said: “Hydrogen has great potential as a clean energy carrier, but it’s notorious for making materials it comes in contact with more brittle. For the first time, we have directly observed how hydrogen changes the way defects in stainless steel behave deep inside the metal, under realistic conditions. This knowledge is essential for designing alloys that are more resilient in extreme environments, including future hydrogen-powered aircraft and nuclear fusion plants.”

As countries aim to transition to fossil-free energy systems, hydrogen has been touted as the ideal fuel for ‘hard to decarbonise’ sectors, such as shipping, aviation, and heavy freight. However, hydrogen can cause unexpected cracking in metals (known as hydrogen embrittlement) which threatens the integrity of high-pressure vessels, pipelines, and critical components in energy systems.

While engineers have long known that hydrogen affects metal performance, the precise mechanisms at the atomic scale have remained elusive, as hydrogen is very difficult to detect.

Study principal investigator Prof. Felix Hofmann (Department of Engineering Science, University of Oxford) explained: “Using coherent X-ray diffraction, a non-destructive method, we were able to watch atomic-scale events unfold in real time inside solid metal without cutting open the sample. It has been tremendously exciting analysing this data and piecing together the parts of this scientific puzzle. Some of the results really surprised us by showing up behaviour we weren’t expecting.”

To uncover what hydrogen does inside the material, the researchers used an ultra-bright beamline at the Advanced Photon Source in the US to focus X-rays onto a single stainless-steel grain, roughly 700 nanometres in diameter. They then applied a technique called Bragg Coherent Diffraction Imaging to measure how the internal structure of this grain changed over time. In this method, the X-rays are scattered by the crystal lattice, creating a complex interference pattern. This can be reconstructed to reveal the structure of the grain, the crystal defects within it and how they distort the lattice around them.

By imaging the steel grain over 12 hours, the experiment revealed three key changes once hydrogen was introduced:

• Dislocations became unexpectedly mobile. Internal faults began to move and reshape themselves, even without additional external stress. This suggests that hydrogen acts like a lubricant at the atomic scale, making it possible for defects to move more easily.
• A surprising out-of-plane motion of defects was observed. This upward shift, known as “climb,” is unexpected and signals that hydrogen allows atoms to rearrange in ways that aren’t typically possible at room temperature. This process is thought to play a critical role in reducing the hardness of alloys.
• The dislocation’s surrounding strain field reduced noticeably as hydrogen accumulated. A strain field is the zone around a defect where atoms are pushed or pulled out of place, allowing the material to accommodate the defect. This study provides the first direct, 3D experimental measurement of a long-theorised effect called hydrogen elastic shielding, where hydrogen reduces defect strain fields, effectively shielding the surrounding metal from stress.

These findings help explain why hydrogen can lead to unexpected failure in metals since it allows internal defects to move more easily and in ways that are not normally possible.

According to the researchers, the work directly informs how to model and predict material performance in hydrogen environments, feeding into multi-scale simulation frameworks used by industry. It also points toward potential strategies for engineering novel alloys that offer greater resistance to hydrogen embrittlement.

Professor Hoffman added: “This research is only possible because of the availability of extremely bright and coherent X-ray beams at international synchrotron sources. The results are highly complementary to information from electron microscopy and simulations. We are now planning even more sophisticated experiments to study how hydrogen changes other types of defects. At the same time, we’re also developing models to help industry design complex hydrogen fuel systems.”

The study also involved researchers from Argonne National Laboratory (United States), and University College London.

Notes to editors:

For media enquiries and interview requests, contact: Professor Felix Hofmann felix.hofmann@eng.ox.ac.uk

The study ‘Direct Imaging of Hydrogen-Driven Dislocation and Strain Field Evolution in a Stainless Steel Grain’ will be published in Advanced Materials at 11:00 am BST Tuesday 9 September 2025 at https://advanced.onlinelibrary.wiley.com/doi/10.1002/adma.202500221 To view a copy of the study before this under embargo contact: Professor Felix Hofmann felix.hofmann@eng.ox.ac.uk

About the University of Oxford

Oxford University has been placed number 1 in the Times Higher Education World University Rankings for the ninth year running, and ​number 3 in the QS World Rankings 2024. At the heart of this success are the twin-pillars of our ground-breaking research and innovation and our distinctive educational offer.

Oxford is world-famous for research and teaching excellence and home to some of the most talented people from across the globe. Our work helps the lives of millions, solving real-world problems through a huge network of partnerships and collaborations. The breadth and interdisciplinary nature of our research alongside our personalised approach to teaching sparks imaginative and inventive insights and solutions.

Through its research commercialisation arm, Oxford University Innovation, Oxford is the highest university patent filer in the UK and is ranked first in the UK for university spinouts, having created more than 300 new companies since 1988. Over a third of these companies have been created in the past five years. The university is a catalyst for prosperity in Oxfordshire and the United Kingdom, contributing around £16.9 billion to the UK economy in 2021/22, and supports more than 90,400 full time jobs.

About Brookhaven National Laboratory

Brookhaven National Laboratory is supported by the Office of Science of the U.S. Department of Energy. The Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, visit science.energy.gov.

 

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Journal

Advanced Materials

DOI

10.1002/adma.202500221 

Article Title

Direct Imaging of Hydrogen-Driven Dislocation and Strain Field Evolution in a Stainless Steel Grain

Article Publication Date

9-Sep-2025

 

Pusan National University researchers reveal how uneven ocean warming is altering propagation of the Madden-Julian oscillation

Uneven ocean warming reshapes the Madden–Julian Oscillation, altering rainfall patterns and challenging climate prediction

Pusan National University

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Uneven Ocean warming shifts the pace of the Madden–Julian Oscillation, reshaping global weather

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Credit: Pusan National University

The Earth’s tropical regions drive some of the most powerful weather and climate variability globally. Among these, the Madden–Julian Oscillation (MJO) is a dominant intraseasonal climate signal, characterized by large clusters of clouds and rainfall that slowly move eastward across the warm tropical oceans. In doing so, the MJO shapes rainfall patterns, influences tropical cyclones, modulates monsoons, and even impacts weather far beyond the tropics. Understanding the factors that govern its speed and intensity is therefore essential for improving sub seasonal to seasonal climate forecasts.

In recent decades, ocean surface warming has been uneven. While most tropical oceans have warmed significantly, the central and eastern Pacific has remained relatively cooler, creating a La Niña–like background state. Around 1999, this asymmetry became more pronounced, raising the question: How have these changing ocean–atmosphere conditions affected MJO propagation?

To investigate this, researchers from Pusan National University examined MJO behavior across two periods: 1979–1998 (pre-1999 conditions) and 2003–2022 (La Niña–like state). The lead researcher, Professor Kyung-Ja Ha explained, “The recent asymmetric tropical ocean warming has driven contrasting changes in the regional propagation of the Madden–Julian Oscillation, with faster propagation over the Indian Ocean and Maritime Continent, but slower propagation over the western Pacific.” The study, published in Communications Earth & Environment on August 14, 2025, highlights how uneven ocean warming can reorganize tropical convection and has critical implications for advancing climate models and improving sub-seasonal prediction.

The study relied on a combination of satellite observations and atmospheric reanalysis datasets. These tools allowed scientists to track intraseasonal variations in convection (via outgoing longwave radiation, OLR), assess sea surface temperature (SST) changes, examine large-scale atmospheric circulation, and evaluate the vertical thermodynamic structure, particularly the role of atmospheric stability and moist processes.

The results revealed stark regional contrasts. Over the Indian Ocean, the MJO propagated eastward more rapidly during the later period, aided by stronger horizontal moisture gradients, enhanced pre-moistening ahead of the convection center, and increased upper-tropospheric stability. Over the Maritime Continent, despite its complex land–sea geography, eastward propagation also accelerated, though less markedly. In contrast, the western Pacific experienced a slowdown, driven by weakened moisture gradients, reduced vertical motion, and lower atmospheric stability, which hindered MJO advancement.

A key insight is the role of atmospheric stability, represented by atmospheric stability, in shaping MJO evolution. By linking stability to intraseasonal variability, atmospheric stability serves as a crucial diagnostic for understanding and predicting MJO dynamics.

These findings have direct implications for weather and climate applications. Prof. Ha shares, “By improving how climate models capture the influence of ocean warming on MJO behavior, seasonal-to-decadal forecasts of rainfall and drought risks can become more accurate. This, in turn, enables governments and local communities to plan more resilient infrastructure, agricultural strategies, and water management systems in the face of climate extremes.” By clarifying shifting tropical climate patterns, the findings help policymakers prioritize adaptation in vulnerable regions.

In conclusion, uneven ocean warming is altering climate states and the MJO’s rhythm. Since the MJO shapes rainfall, cyclones, and stratospheric processes, accurately capturing its dynamics is vital for better global forecasts in a warming world.

This study was supported by the PNU Global—Learning & Academic research institution for Master’s, PhD students, and Postdocs (G-LAMP) Program.

 

***

 

Reference
DOI: 10.1038/s43247-025-02652-z

 

About Pusan National University
Pusan National University, located in Busan, South Korea, was founded in 1946 and is now the No. 1 national university of South Korea in research and educational competency. The multi-campus university also has other smaller campuses in Yangsan, Miryang, and Ami. The university prides itself on the principles of truth, freedom, and service and has approximately 30,000 students, 1,200 professors, and 750 faculty members. The university comprises 14 colleges (schools) and one independent division, with 103 departments in all.

Website: https://www.pusan.ac.kr/eng/Main.do

 

About the author
Professor Kyung-Ja Ha is a climate physicist at the IBS Center for Climate Physics and Pusan National University, where she leads the Global Monsoon Climate Lab. She has served as president of the Korea Meteorological Society and as a member of the Presidential Science and Technology Advisory Committee. With more than 300 publications and 7,000 citations, her research focuses on monsoon dynamics, hydroclimate, and tropical–extratropical interactions. This study was supported by the Global–Learning & Academic Research Institution for Master’s, PhD students, and Postdocs (G-LAMP) Program of the NRF, funded by the Ministry of Education (No. RS-2023-00301938).

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Journal

Communications Earth & Environment

DOI

10.1038/s43247-025-02652-z 

Method of Research

Data/statistical analysis

Subject of Research

Not applicable

Article Title

Recent asymmetric tropical ocean warming has altered regional propagation of Madden-Julian Oscillation

Scientists find curvy answer to harnessing “swarm intelligence”

Breakthrough offers way to develop AI to match flocking birds and schooling fish

New York University

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Pictured above are robots, used in the Proceedings of the National Academy of Sciences study, that have the potential to advance "artificial swarm intelligence"—a type of AI that mimics flocking birds and schooling fish.

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Credit: Image courtesy of the Department of Artificial Intelligence, the Donders Center for Cognition, Radboud University. Photo Credit: Luco Buise.

Birds flock in order to forage and move more efficiently. Fish school to avoid predators. And bees swarm to reproduce. Recent advances in artificial intelligence have sought to mimic these natural behaviors as a way to potentially improve search-and-rescue operations or to identify areas of wildfire spread over vast areas—largely through coordinated drone or robotic movements. However, developing a means to control and utilize this type of AI—or “swarm intelligence”—has proved challenging. 

In a newly published paper, an international team of scientists describes a framework designed to advance swarm intelligence—by controlling flocking and swarming in ways that are akin to what occurs in nature.

“One of the great challenges of designing robotic swarms is finding a decentralized control mechanism,” explains Matan Yah Ben Zion, an assistant professor at the Donders Center for Cognition at the Netherlands’ Radboud University and one of the authors of the paper, which appears in the journal Proceedings of the National Academy of Sciences. “Fish, bees, and birds do this very well—they form magnificent structures and function without a singular leader or a directive. By contrast, synthetic swarms are nowhere near as agile—and controlling them for large-scale purposes is not yet possible.”

The research team, which included NYU scientists Mathias Casiulis and Stefano Martiniani, addressed these challenges by developing geometric design rules for the clustering of self-propelled particles. These rules are modeled using natural computation—similar to the “positive” or “negative” charges in protons and electrons that are foundational to the formation of matter. 

Under these rules, active particles moving in response to external force have an intrinsic property that causes them to curve—a quantity the researchers call “curvity.” 

“This curvature drives the collective behavior of the swarm, which points to a means to potentially control whether the swarm flocks, flows, or clusters,” explains NYU’s Martiniani, an assistant professor of physics, chemistry, and mathematics. 

Their conclusion was supported by a series of experiments in which the scientists showed that the curvature-based criterion controls robot-pair attraction and naturally extends to thousands of robots. Each robot was treated as having a positive or negative curvity, and similar to electric charge, this curvity controls the robots’ mutual interactions. 

“This charge-like quantity, which we call ‘curvity,’ can take positive or negative values and can be directly encoded into the mechanical structure of the robot,” explains Ben Zion. “As with particle charges, the value of the curvity determines how robots become attracted to one another in order to cluster or deflect from one another in order to flock.” 

Ben Zion, who as an NYU student previously developed microscopic swimmers added: “Finding a design rule of geometric nature, such as curvature, makes it applicable to industrial or delivery robots or to cellular-sized microscopic robots that have potential to improve drug delivery and other medical treatments.” 

“The best part is that these rules are based on elementary mechanics, making their implementation in a physical robot straightforward,” adds Casiulis, a postdoctoral researcher at New York University’s Center for Soft Matter Research and NYU’s Simons Center for Computational Physical Chemistry. “More broadly, this work transforms the challenge of controlling swarms into an exercise in material science, offering a simple design rule to inform future swarm engineering.”

The study’s other authors were Tel Aviv University researchers Eden Arbel, Yoav Lahini, and Naomi Oppenheimer and Radboud University researcher Charlotte van Waes.

Pictured above are robots, used in the Proceedings of the National Academy of Sciences study, that have the potential to advance "artificial swarm intelligence"—a type of AI that mimics flocking birds and schooling fish.

Credit

Image courtesy of the Department of Artificial Intelligence, the Donders Center for Cognition, Radboud University. Photo Credit: Luco Buise.

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Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2502211122 

Article Title

A geometric condition for robot-swarm cohesion and cluster–flock transition

Article Publication Date

8-Sep-2025