Since Star Trek began sending its crews out to explore strange new worlds 60 years ago, the franchise has both imagined and inspired new concepts for travel across the vast distances of space.

Among the most intriguing are “wormholes”: mysterious tunnels through spacetime that connect otherwise distant places.

Star Trek always has a difficult balance to strike in making its portrayals both accessible and scientifically accurate. With wormholes, it generally favoured the former on their occasional appearances.

On screen, one end of the wormhole will often appear as a swirling vortex or tunnel. In fact, computer simulations of these theoretical space shortcuts suggest that the opening would look more like soap bubbles or crystal balls, with their surfaces showing distorted and multiplied images of whatever lies on the other side.

You could fly all around this opening and enter it from any direction, and rather than reaching the centre of the bubble, you would emerge from another similar bubble (the other end of the wormhole) somewhere totally different.

Of course, the most important question for both Starfleet captains and theoretical physicists is: should you fly into a wormhole? The job of a starship captain may be to boldly go, but as a very risk-averse physicist, I’m not so sure.

The first Star Trek wormhole

“Wormhole distortion has overloaded the main power systems!” These words, spoken by Commander Willard Decker in Star Trek: The Motion Picture (1979), marked the first appearance of a wormhole in Star Trek.

A warp drive malfunction leads to the creation of a distorted region of spacetime that sucks in the Starship Enterprise, leading to a breakdown of the ship’s systems and a potentially deadly collision with a random asteroid.

It is a typically pioneering reference to what was, at the time, a niche research topic. John Wheeler, professor of gravitational physics at Princeton University, had first coined the term with Charles Misner in their 1957 paper Classical Physics as Geometry, which aimed to describe electric charges like electrons as the ends of tunnels in space.

The first descriptions of traversable wormholes that satisfied Einstein’s equations of general relativity – configurations of matter that balance the spacetime curvature of the tunnel – were then independently published by H.G. Ellis and K. A. Bronnikov in 1973, although they didn’t use Wheeler’s moniker.

Six years later, the first Star Trek wormhole wasn’t an accurate depiction of what scientists and science fiction enthusiasts now understand by the term. For one thing, the wormhole doesn’t appear to lead anywhere, and it dissipates once the crew regain control of the ship and drop out of warp speed.

Nevertheless, as a researcher studying black holes and the early universe, I am rather fond of this scene – in part because it is actually possible to imagine warp drives (engines that bend spacetime to move the ship at faster-than-light speeds) distorting spacetime in this way.

If you put exotic matter (one with a negative pressure) into a small region of spacetime, Einstein’s equations of general relativity tell us that region can expand exponentially fast. And if the space around it is not expanding in the same way, where can all that new space go?

The answer, at least in this hypothetical scenario, is that it must balloon out into an entirely new universe, creating a wormhole in the process – a narrow passage that links the two regions.

If you’re thinking this sounds implausible, Einstein’s theory of general relativity is actually perfectly ok with things being larger on the inside. Indeed, such scenarios may (speculatively) have arisen from rare fluctuations in the early universe.

No slow-mo

Star Trek’s first depiction of a wormhole gets one aspect precisely wrong, though. In the film, the wormhole’s “temporal distortion” makes the crew move and speak in slow motion, struggling to fire the photon torpedoes that will save them from asteroid-impact obliteration.

While the gravitational time dilation predicted by Einstein could be a feature of wormhole spacetimes, it would not be experienced as slow motion by those who fly in. For them, time would pass completely normally, with their watch ticking at one second per second.

They might, however, emerge to find that their friends had aged far more than they had. But these friends wouldn’t have experienced time in fast-forward either. Both sides think time has passed normally, they just disagree about the amount.

Again, this seems like it shouldn’t really be allowed – but the same effect is experienced by clocks on GPS satellites put into orbit around the Earth. When brought back to Earth again, they are found to have experienced more time than an equivalent clock left on the Earth’s surface, due to having spent time in a weaker gravitational field.

Next Generation wormholes

By the late 1980s, Star Trek wormholes had achieved the ultimate sign of technological maturity – somebody was trying to sell one.

This depiction, in the series Star Trek: The Next Generation (1987-94), more closely resembled the traversable wormhole framework co-developed by Kip Thorne in 1988. The US astrophysicist and future Nobel laureate had begun exploring the theoretical requirements for the existence of wormholes as portals connecting distant regions of space in the same universe.

Thorne showed that for a wormhole to be held open in a way that makes it traversable would require an exotic form of matter, violating certain energy conditions that physicists think ought to be respected at large scales.

As the Next Generation crew find out, you don’t just want to buy any old traversable wormhole – you need it to be a stable one. The original Ellis-Bronnikov wormhole uses the right kind of exotic matter as scaffolding to hold it open. But even tiny disturbances will cause it to rapidly collapse – as has been demonstrated in many numerical simulations.

A spinning version of the Ellis-Bronnikov wormhole appears potentially more robust, but its so-called “nonlinear stability” is yet to be established. Flying a starship through one of these would be a useful, if rather risky, test.

The space between what is mathematically possible and physically realistic has always been a key part of the magic of Star Trek, inspiring several generations of scientists to explore strange new spacetimes. But if a soap-bubble wormhole ever appears in front of my spacecraft, I would always let Starfleet go first.

Katy Clough receives funding from the Science and Technology Facilities Council (STFC) and the Simons Foundation. She will be speaking at the Star Trek Lates event at the Science Museum in London on Tuesday, September 8.

Government experts are meeting in Geneva, Switzerland, to work towards a possible negotiating mandate on autonomous weapons systems (AWS). These are military systems that can select and engage targets without human intervention.

This major international gathering follows a recent call by the UN and the International Committee of the Red Cross (ICRC) for urgent controls on these weapons, sometimes dubbed “killer robots” in descriptions by the media.

Recent events in Ukraine have further consolidated concerns that a slide towards weapons with full autonomy (and without meaningful human control) is well underway. According to the New York Times, a Russian drone attacked a petrol station in Zaporizhzhia on July 6, killing three civilians. What marked it out was the drone’s use of AI to decide where and when to strike.

The drone aircraft had been programmed to fly towards the petrol station. But on its approach, an AI system autonomously chose the precise target – probably propane tanks – based on its ability to recognise them.

On August 25, Mirjana Spoljaric, the president of the ICRC, and António Guterres, the secretary-general of the United Nations, issued their joint appeal to the international community to agree on legally binding rules regulating the development and use of AWS.

New technologies are making it cheaper and easier for nations to put together these weapons. Thus, the UN and ICRC appeal for binding rules could not be more urgent. The international community is ideally placed to start negotiations soon, building on many years of diplomatic talks.

For the past decade, governments have debated how AWS challenge existing international law and what should be done under the auspices of the convention on certain conventional weapons, a UN arms control framework. Since 2017, the group of governmental experts (GGE) on lethal autonomous weapons systems (LAWS) – which is part of the convention on certain conventional weapons – has convened typically twice a year.

The experts are meeting again this week in Geneva. The aim is to agree a governance framework and language for a rolling text that could be the foundation for negotiations. This text provides a baseline for continued discussions in November.

While this process has been rife with political disagreements, most experts agree on the need to retain some level of meaningful human control over the use of autonomous systems.

Moral significance

This demonstrates a shared sense by states participating in the process that human judgment is pivotal for the laws governing warfare. It also shows that the moral significance of warfare underlines the importance of human responsibility.

Human judgment is also embedded in international humanitarian law. Targeting processes require context-specific judgments about the targets themselves, potential harm to civilians from striking the target and other precautions. These tasks cannot be delegated to machines.

AI-enabled systems show how technology already shapes human perceptions of targets and risk. With autonomous weapons, the system shifts from influencing human judgement to exercising the targeting function itself.

Any AI system is only as good as the data it has been trained on, or that it works with. For armed conflicts, this data is difficult to come by and is almost always insufficient for dynamic and variable human contexts. This means many systems are likely to be technically inadequate.

The problem becomes quite visible with rules around assessing proportionality, for example, which is a context specific judgement about anticipated civilian harm versus military advantage.

Militaries may try to quantify targeting decisions in a way that creates the appearance of precision. However, the underlying legal judgment remains qualitative regardless. Technical accuracy, therefore, is not the same as lawfulness or moral consideration.

Only humans can understand the significance of respecting the inherent rights and dignity of other humans. Decisions to end human life must therefore be made qualitatively, by humans, in order to be morally and legally justifiable. Without this provision, and clear guidelines around it, we argue that governments risk running into a legal vacuum and a steep moral abyss.

AWS, especially those that prioritise speed and scale of action though AI, carry a significant risk of enabling an uncontrolled and rapid escalation. Escalation from crisis to war, or from conflict to a higher level of violence, could come about by erroneous indications of attack or by a simple sensor or computer error.

Unpredictable systems could give leaders false impressions of the capabilities of those systems. This could lead to overconfidence or encourage preemptive attacks.

Inevitable outcome?

One argument raised by academic researchers in the context of AWS is that they become necessary because they are inevitable. The risk is that more countries opt for full autonomy as components become cheaper and readily available, exacerbating an arms race.

However, an adversary’s conduct does not release a state from its own obligations under international humanitarian law. Following those rules is also part of what makes military force legitimate, including through civilian protection, precautions and accountability. We might turn the argument around and say: legally binding rules become inevitable, because they are absolutely necessary.

Governments and advocacy groups have worked hard over the past decade to put together a lucid proposal for the regulation of AWS. Some efforts are intended to prohibit those systems that target humans directly, or that are unpredictable and therefore cannot be meaningfully controlled by a human. All other AWS must be strictly regulated.

There are signs of political momentum. In November 2025, 156 states voted in favour of a UN General Assembly resolution that “draws attention to the serious challenges and concerns” that autonomous weapons raise. A legally binding instrument is possible, even if some states resist it.

The time is now. Clear, binding rules would help ensure that increasingly autonomous warfare does not make violence easier to unleash and harder to control.

Elke Schwarz is Vice-Chair for the International Committee for Robot Arms Control.

Jessica Dorsey is affiliated with Airwars as a member of the Executive Board and a member of the Advisory Board of the Atlantische Commissie.

In this Op-Ed piece, Samreen Makhfi, an Afghan woman currently living in Afghanistan, reflects on life in Afghanistan five years after the Taliban’s return to power, using the country’s Independence Day—August 19—as a contrast between its historical aspirations and present conditions. The Debrief’s Chrissy Newton contributed to this report.

Today is August 19, 2026. One hundred and seven years ago, on this day, King Amanullah Khan declared Afghanistan independent. Were Queen Soraya alive to witness this day, sorrow would overwhelm her. Perhaps sorrow would be too small a word.

She carried the torch of education for Afghan girls, believing that a nation could not walk forward while half of its people were kept behind. Now that torch seems to have been extinguished by decrees and prohibitions. Girls are shut out of secondary school and university. Women’s paths into professions that once promised them a future as teachers, doctors, engineers, and artists have narrowed or disappeared. They are granted only the bitter permission to survive, polishing men’s shoes until their hands harden, and begging in the streets until their voices become hoarse. 

My sister tells me she even misses the honking of the car that used to take us to school, that impatient horn we once felt irritated by. Back then, she complained about waking up too early and counted the days until holidays. Now she says, “I even miss the feeling of being sleepy, the heavy eyelids, the rush of morning air, the chatter of classmates as soon as we entered the gate.”

What once felt like a burden became a relic. I miss the little shop near our school. I remember the elderly uncle who seemed to know exactly how easily my sweet tooth could betray me. He would smile when he saw us and say, “I’ve brought a new flavor of cupcakes and chocolate.” It is strange how oppression can make you nostalgic for things you once considered ordinary.

Consequences of closing those classroom doors reach far beyond the girls sitting behind them. Afghan men want female doctors to treat their wives, mothers, and daughters. They want women to be cared for by women, especially in matters of health and childbirth. But how can tomorrow’s female doctors exist when today’s girls are prevented from becoming students? The ones who are denied education are the very girls who could have filled those roles. 

Decree No. 18, issued in May 2026, states that a girl’s silence after puberty can be interpreted as consent to marriage. Imagine being too young to understand what marriage means, yet old enough, according to the law, for your silence to be placed on a contract you never knew you were signing. And if that marriage becomes a place of violence rather than safety, escape is not equally available to her. Men retain unilateral divorce rights, while women face restrictive judicial avenues for separation. Even the language of the law can become another wall between a woman and the life she wants to reclaim.

However, the walls do not end at the home. The country’s beauty is fenced off, too; women are not allowed to visit many tourist sites, even with their families. Restrictions on women’s access to public spaces have made ordinary pleasures such as parks, public places, and travel another negotiation with authority. I think of Qargha. Its waters glitter beneath the sun, and the breeze carries the scent of pine. Somewhere in that landscape, a girl should be able to laugh beside the water and to dip their hands into its coolness. But even the beauty of the country can become gendered. The mountains remain visible. The lake remains blue. The wind still moves through the trees. Only the people allowed to enjoy them have changed.

At this point, men’s situation is no better than ours. University graduates joke bitterly, “We successfully completed the journey from ‘university students’ to ‘unemployed’.” The joke lands because everyone knows a degree has become a piece of paper. A profession has become a distant possibility. A young person looks toward adulthood and finds the road strangely empty. One of today’s high officials even declared that political loyalty can matter more than merit in terms of opportunities. 

Once, even our flawed elections gave us the illusion that our voices could tug, however weakly, on the direction and fate of the country. The ballot box was imperfect, but it gave people the sensation of having a hand on the wheel. Now even that thread has snapped. There is no ballot to mark, no campaign to argue over, no candidate to disappoint us after promising something better. Right now, citizens have no say in the politics of their country. In the media, the only journalists who can survive are those who avoid talking about everything that is going wrong. And underneath the politics is something much more immediate.

Bread

For many families, bread is scarce, and work is scarcer. Poverty does not always arrive dramatically. Sometimes it is an empty cupboard and fridge, a postponed purchase, or a child asking for something that a parent cannot afford. Sometimes it is watching one family struggle while another, somehow, continues to live comfortably, its pockets lined with opportunities that seem to belong to a different Afghanistan.

Leaving has become its own kind of privilege. A person can dream of another country and still find the border of that dream closed. Visas are denied or restricted, and the simple desire to travel somewhere else, to see another country, breathe different air, return home again, can become almost impossible. And yet, even in the face of closed borders, desperation has driven many Afghans to move anyway.

Many, overwhelmed by the hopelessness of life here, have even fled toward Iran while war was still raging there. They looked at a country caught in conflict and somehow decided that perhaps danger there was preferable to the life waiting for them here. There is something devastating about that calculation. When people begin comparing one war with another and asking which one might be easier to survive, you know home has stopped feeling like home.

Afghanistan remains

The mountains have not packed their bags. The morning sun still spills over Kabul. Children still laugh. Mothers still cook. Someone still opens a shop in the morning. Someone still remembers the taste of a particular chocolate. Somewhere, perhaps, a girl still keeps an old school notebook tucked inside a drawer, its pages filled with handwriting from a life that feels increasingly distant. And still, some study through second‑hand phones, and some work online.

Perhaps the world remembers us; perhaps it has turned away. But the true heroes are those who carry our story in their lungs, those who breathe it in, breathe it out, and refuse to let silence become the final language of Afghanistan.

Poem by Samreen Makhfi

It is the fifth year now and the walls 

are coming closer

inch by inch, stone by stone

I come to the tree

 

The same one that has stood through 

all our years, older than my father

older than his father, a witness planted 

deep in the bones of Kabul

 

It remembers the golden days

of Zahir Shah, and the ones that followed 

It saw the first Taliban rise

and watched them fall

 

It watched the Republic arrive with its 

promises, its flags, its endless foreign money 

pouring into the pockets of men who enjoyed 

themselves in air-conditioned rooms when civilians 

 

paid with their blood 

Then it saw them return. Again.The Taliban

I place both hands on the trunk

and shake it with everything I have

 

The bark scrapes my palms

The smell of sap rises into my throat

“Tell me,” I scream, “how can you still stand?”

“How, when you have seen everything?”

 

Great-grandfather cut your branches

for the bitter winters, and you grew them back.

Grandfather carved your strong wood

into a swing for his grandsons,

 

Father sat beneath your shadow

when the Kabul sun burned the streets white.

And you–you still stand.

I press my forehead against your skin.

 

You are warm. Steady. Alive.

I am here to borrow some of your strength.

I am tired of history repeating itself 

I am tired

I am tired

I am tired

Samreen Makhfi is the pen name of an Afghan woman currently living in Afghanistan. 

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