How do we know we’re not living in a computer simulation? Is it even possible to tell? For what it’s worth, researchers have drawn from various scientific frameworks to reject this hypothetical hypothetical reality—and a team of mathematicians now says they’ve taken the argument a step further.
In a Journal of Holography Applications in Physics study published earlier this year, researchers demonstrated that, assuming the universe runs purely on mathematics and physics, it would be impossible for any algorithm to simulate reality as we know it. This is because the universe exists “on a type of understanding that exists beyond the reach of any algorithm,” the researchers explained in a statement.
“Drawing on mathematical theorems related to incompleteness and indefinability, we demonstrate that a fully consistent and complete description of reality cannot be achieved through computation alone,” Mir Faizal, a physicist at the University of British Columbia in Canada, added in the statement.
You might want to concentrate for this part
The model builds on several mathematical theorems, including Gödel’s incompleteness theorem. This idea, announced by the eponymous scholar in 1931, very simply states that no set of axioms, or algorithm, can perfectly prove every true fact about numbers.
For instance, an algorithm would have trouble parsing the statement “This true statement is not provable.” If the statement were provable, it’d be false and illogical. If it weren’t provable, then it’s true, but how would the algorithm compute an answer?
This might sound like a pointless exercise, but it highlights a key aspect of mathematical endeavors—or, in this case, computation—that it’s bound to whatever mathematicians set as their starting assumptions. This is evident in the history of physics, the researchers explained, as humanity has transitioned from Newtonian physics to Einstein’s general relativity and now to quantum mechanics and beyond.
In the context of the universe, this suggests that there will always be a deeper layer of reality, an “information-based foundation” that cannot be fully described by computation alone, according to the paper. An obvious example of this is that human mathematicians can easily grasp “Gödelian” truths, like the statement “This true statement is not provable,” whereas computers cannot.
“Any simulation is inherently algorithmic—it must follow programmed rules,” Faizal said. “But since the fundamental level of reality is based on non-algorithmic understanding, the universe cannot be, and could never be, a simulation.”
A theory of everything?
On the other hand, the researchers’ calculations suggest that we may never arrive at a “theory of everything”—at least not one that operates algorithmically. The so-called theory of everything—a holy grail among physicists—works beyond computation, according to the researchers. If a complete, consistent understanding of reality were to lie outside the realm of formal rules, it would be illogical to believe that they could even exist, the researchers noted.
The paper offers fascinating food for thought while subtly expressing appreciation for the natural complexity of the universe. Then again, humans have a tendency to anthropomorphize most things. While I have no qualms against Gödel’s theorem, can it definitively prove something to be impossible—if that something potentially lies beyond the capacities of the human brain?
I am not sure. But I might be nitpicking. I’ll have to ask my simulation operator.
Daniel Whiteson and Andy Warner’s upcoming book, Do Aliens Speak Physics? And Other Questions about Science and the Nature of Reality presents the best combination of all these things. The book imagines what it would be like to discuss physics with aliens, drawing from a diverse array of experts in the history and philosophy of science—accompanied by Warner’s delightful illustrations plus physics puns and hypothetical donuts.
Co-author Daniel Whiteson is a particle physicist at CERN and the University of California, Irvine, as well as a science communicator and host of the podcast Daniel and Kelly’s Extraordinary Universe. Gizmodo spoke to Whiteson about the philosophical nature of the search for aliens and what it reveals about our own humanity. The following conversation has been lightly edited for grammar and clarity.
Gayoung Lee, Gizmodo: Okay, so, do aliens speak physics? What is this question even asking?
DanielWhiteson: I don’t know if aliens speak physics! That’s why I wrote this book, to argue both sides of this question. I feel like a lot of physicists assume that the physics we are doing is universal… that the way we’re doing things and our way of life is the only way.
I wanted to push back on that a little bit and explore and make the opposite argument and suggest that there might be a lot of humanity in the physics that we’re doing—the way we think about it, the questions we’re asking, the answers we accept, and our path into physics.
Gizmodo: At the very start of your book, you introduce an extended version of something called the Drake equation. What is it, and how have you reimagined it?
Whiteson: The Drake equation is a fun way to organize your thoughts about whether there are other intelligent civilizations in the galaxy. There have to be stars or planets for them, life that evolved to develop sentience and technology, and they have to do it all roughly within a time window that we can communicate with them.
It breaks these features apart because they are separate issues. It emphasizes something really crucial: you’ve got to have all the pieces to work. If any of those numbers go to zero, you’re out of luck.
But in the book, we’re not just interested in intelligent aliens. We want to find intelligent aliens that do science the way that we do so we can learn from them. Otherwise, it’s just too big a space to explore, and all those things must come together for this intergalactic science conference that is my personal fantasy.
Gizmodo: Okay, so let’s unpack some of these additions. The first one is about whether aliens do science at all.
Whiteson: Sure. This was tricky to tackle. I think a lot of people assume that if aliens arrive, they’re technological—because they’ve gotten here. They have some way to cross the vast distances between the stars, so they must have a scientific understanding of how they did that.
But historians of science and philosophers of science understand that technology doesn’t require science. We’ve been using stone tools for millions of years. We had technology in terms of writing, fermentation, metallurgy, and agriculture. These are technological improvements that have improved our lives without us understanding how they worked.
Having a scientific mindset is going to accelerate your technology, but it’s not essential. So that’s what we dig into in that question. Is science actually essential? What is science anyway?
Gizmodo: So assuming aliens are scientific, another element is whether they ask the same questions.
Whiteson: One motivating piece of philosophy for me was this question of emergence—why is the universe understandable at all? We can use fairly simple mathematical tools to understand the world around us. Instead of the universe just being filled with chaos, somehow this simplicity emerges.
We don’t know what the fundamental layer of reality is—if it even has one. So, all of our science studies emergent phenomena. It might be that it’s sort of a way we filter the universe. The universe is crazy and filled with all sorts of buzzing noise, but we see certain stories that are of interest to us.
On the other hand, if emergence is something that’s part of the universe—like there’s just some way things average out—then we’ll have that in common with aliens. They’ll study planets the way that we do. They’ll study particles the way that we do. They’ll see the same simple stories. But it’s not something we know the answer to until they show up.
Gizmodo: Do you think there’s any point in trying to communicate with animals on Earth to prepare for aliens? It can be argued that interspecies communication among animals on Earth has practically zero bearing on how an extraterrestrial, intelligent being might message us.
Whiteson: I think I would disagree. I mean, I agree that it’s unlikely that learning dolphin is going to help us communicate with the aliens. But the fact that we’ve failed to communicate with those species tells us that we have a lot to learn about talking to other species and that more practice and more success could set us up for more success in the future.
There are definitely some assumptions we’re making and some barriers we haven’t pushed through. So, we can’t understand why or how whales are singing to each other and how bats are clicking to each other, but there’s definitely something going on there.
Gizmodo: The extended Drake equation isn’t a yes-or-no question on whether aliens exist. It’s an ideal scenario in which we could have a meaningful, intellectual exchange with them.
Whiteson: Yeah.
Gizmodo: I’m sensing that makes it even harder for us to encounter the “ideal” alien civilization. In your view, what is the worst-case scenario that doesn’t end with everyone on Earth dying?
Whiteson: (Laughs) Yeah, well, one amazing outcome is that we have everything aligned with them. They just tell us the answers, and we’re catapulted into the future of science—incredible!
More frustrating, what you might call a worst-case scenario, is that there is nobody else out there doing science the way that we are. They’re not interested in our questions. They’re looking for different answers. They see a different slice of the universe—we’re alone at the table at the Intergalactic Science Conference. That would be unfortunate.
From a philosophical point of view, it might be more fun if the aliens don’t satisfy any of our requirements, because that’s when we learn about our own peculiarities. Like, “Oh, wow, that is interesting that we do this science this one way, and everybody else is doing it that way. What does that mean about being human?”
So I think the philosophers would be more excited if we were the only ones in the galaxy doing science this particular way. But the physicists would be frustrated for sure.
Gizmodo: On that note, is the search for intelligent alien life really humanity’s own ego search?
Whiteson: Oh, for sure. Definitely. On one hand, we want to find aliens similar to us, because it validates us. On the other hand, that discovery, finding lots of human-like aliens, would make us less special.
My favorite thing about searching for aliens is that any answer is mind-blowing and wonderful in its own way. So, I’m definitely pro-aliens, no matter what. Even if the aliens show up and do send us to the hydrogen mines, I still think that would be interesting. I’m that much pro-alien visitation—I’ll take the risk!
Gizmodo: The book presents an impressive union of philosophy and science, but you’re a physicist at heart. So, having written this book, doing the research for it… How has the process changed the way that you approach your own work as a scientist?
Whiteson: Good question. You know, I’ve always been interested in philosophy at an amateur level. But I realized that particle physics is filled with people who have strong philosophical opinions but think philosophy is a waste of time. They have this [Richard] Feynman attitude that physicists need philosophers the way birds need ornithologists.
If you ask them, is the top quark real? Was it there before we discovered it? They’ll say, “Of course, what are you, an idiot? Of course it is. It’s physical; it’s there. We found it; we didn’t create it.”
… I found those two things in conflict. Yeah, we didn’t create these particles, but we never see them, we don’t hold them in our hands, and we don’t interact with them. We’re telling stories about the way the universe works. But in the end, those are stories, and they’re stories that satisfy us. We don’t know if the same stories would satisfy other people, so it definitely shines a light on my own work and makes me wonder what it means.
But even if physics isn’t universal, it doesn’t make me less interested in doing physics. I still think it’s a super fun puzzle to try to unravel the universe. We’re in this intimate relationship with the universe, and it matters what matters to us. It’s part of being human.
Do Aliens Speak Physics? is being published by W. W. Norton & Company and will be available online or in hardcover on November 4, 2025.
For various, typically historical reasons, even the best physicists claim things that sound egregious to modern observers. That doesn’t necessarily mean these ideas are completely useless—if anything, theories once dismissed might just be what scientists need to break a stalemate in existential physics.
Writing for Physical Review Letters, a team of Japanese physicists does exactly that, offering a new interpretation of an 1867 theory describing atoms as “knots” in the aether. The paper does not advocate for aether, the so-called “fifth” element from ancient and medieval science. Rather, the researchers consider a version of the universe’s history where cosmic knots of energy slowly untangled into matter as we know it today.
A knotty problem?
All matter in the universe has an evil twin: antimatter. These particle pairs should’ve canceled, or annihilated, each other after the Big Bang, leaving nothing behind save for a universe brimming with radiation. Physicists aren’t entirely sure why this happened, but it seems a slight imbalance in favor of matter won out, resulting in everything we see around us, including our own physical existence. Physicists have devised various accounts to explain this paradox, known as the matter-antimatter asymmetry, through a mechanism called charge-parity (CP) violation, but no clear solution exists.
William Thomson—also known as Lord Kelvin—believed that atoms were essentially knots, “mathematically defined as closed curves embedded into three-dimensional space,” according to the paper. The researchers’ revival of this theory applies the idea of knots to wave packets of energy propagating through the early universe. After the Big Bang, a series of phase transitions generated cracks in space, leaving behind “thread-like defects” from the explosion.
The cosmic knots would form as these filaments became entangled by the expansion and contraction of spacetime, the researchers said. Eventually, the knots untangled through quantum tunneling—the phenomenon behind this year’s Nobel-winning physics—allowing particles to pass like ghosts through barriers in the quantum realm.
A cosmic family tree
If these knots had a slight bias toward matter over antimatter, their unraveling could help explain the matter-antimatter imbalance, the paper stated. A thorough mathematical investigation of this hypothesis confirmed that, at the very least, the theory holds up.
“Basically, this collapse produces a lot of particles,” Yu Hamada, study co-author and a particle physicist at Keio University in Japan, said in a statement. These particles include a form of neutrino—electrically neutral particles with near-zero mass—whose decay can “naturally generate the imbalance between matter and antimatter,” Hamada explained.
“These heavy neutrinos decay into lighter particles, such as electrons and photons, creating a secondary cascade that reheats the universe,” he added. “In this sense [neutrinos] are the parents of all matter in the universe today, including our own bodies, while the knots can be thought of as our grandparents.”
The new proposal presents one novel approach to thinking about the matter-antimatter problem, but the researchers admit that, as of now, the theory is still a theory. However, their calculations suggest that collapsing cosmic knots should leave behind strings—structures that gravitational wave observatories, such as LIGO or LISA, should be able to detect.
And if they can, that would be a field day for string theory enthusiasts.
Quantum computers are already here, even though it’s not readily apparent. Now, researchers say quantum advantage—the field’s long-promised milestone of outperforming classical computers—appears to have finally arrived. But the story comes with an important caveat.
Research by scientists at the University of Texas at Austin and Colorado computing firm Quantinuum devised and carried out an experiment that demonstrates “unconditional” quantum advantage, sometimes referred to as quantum supremacy. As the researchers phrased it, their “result is provable and permanent: no future development in classical algorithms can close this gap.” The preprint, which has yet to be peer reviewed, was made available on arXiv earlier this month.
Gizmodo reached out to several experts in the field, who affirmed the new results. They added that the experiment, while commendable, isn’t the most practical use of a quantum computer—which already gets flak for its uselessness to everyday users.
Then again, “quantum advantage” is a weird, surprisingly malleable concept with many possible applications. Overall, the results are definitely worth a closer look.
Alice and Bob make a cameo
Quantum enthusiasts may be familiar with Alice and Bob, two fictional characters often summoned for quantum thought experiments. In the context of the new experiment, Alice and Bob are two researchers collaborating on a computation using a single device. They receive different inputs at different points in time, but only Alice can send Bob a message, and not the other way around. Based on Alice’s message, Bob must decide how to measure and interpret to produce a final output.
According to the paper, “the use of a quantum message can provably reduce the amount of communication required by an exponential factor compared to any protocol that uses classical communication alone.” In other words, a small quantum message can replace a much larger classical one. To prove their point, the team repeated the experiment 10,000 times on Quantinuum’s H1-1 trapped-ion quantum computers, coupled with a careful mathematical validation of their protocol.
Surprisingly, they found that a quantum computer only needed 12 qubits (qubits are the smallest unit of information for quantum computers) to solve this problem. By contrast, even the most efficient classical computers needed 330 bits.
A different way to play the game
“This is a very different type of quantum advantage than we have seen before—not better or worse, but it’s just proving something completely different from past experiments,” Bill Fefferman, a computer scientist at the University of Chicago, told Gizmodo in an email. Fefferman previously collaborated with senior author Scott Aaronson but wasn’t involved in the new study.
Fefferman explained that scientists typically equate quantum advantage to “striving to perform a computation on a quantum computer that can be solved dramatically faster than any classical computer.” By contrast, the new experiment achieves “quantum information supremacy,” in which the focus isn’t so much on speed as it is on using fewer qubits to solve a problem that classical computers need many more bits to crack.
“It is true that their result is unconditional, in the sense that it doesn’t rely on unproven assumptions,” Fefferman said. “This is, of course, a great feature of this new experiment, but it’s also inherited by this ‘moving of the goalposts.’”
Gizmodo contacted the study’s authors, who said they couldn’t comment until the paper is formally published.
Pressing the advantage
The results raise questions about the broader goals of proving quantum advantage. As IBM Quantum’s director told Gizmodo in a previous interview, a potential answer is to ask how quantum computers can enhance computing problems we’re already familiar with.
But as Fefferman noted, there isn’t necessarily a better or worse approach for arriving at quantum advantage—although this “goalpost” appears to be the holy grail for the field’s struggle to prove its worth.
That may be a product of quantum computing’s history, Giuseppe Carleo, a computational physicist at EPFL in Switzerland who wasn’t involved in the new work, explained to Gizmodo in a video call. The rapid growth of quantum computing makes it easy to forget how recently the right hardware became available to test theory.
“So the field has developed historically in the past 20, 30 years much closer to mathematics, rather than an applied field where, if you want, you can use a machine to run things,” said Carleo, who spoke with Gizmodo about the history of quantum computing. As a result, most of the analysis in the field remained at theoretical levels for a longer time than scientists would’ve hoped.
But with hardware advances and a fast-growing industry, this trend is gradually shifting—as it should, Carleo said. More projects are moving away from designing quantum advantage experiments “specifically tailored to show advantage,” he said, turning instead to places where quantum computers can help, not necessarily upend.
That’s actually closer to the field’s “origins,” he added. Richard Feynman, the physicist instrumental to quantum computing’s foundations, suggested that quantum computers should predict quantum phenomena. Sure, there might not be so much “money attached to it,” but they are “of tremendous interest for theoretical physics,” particularly with regard to fundamental questions about our universe, Carleo explained.
Quantum-anything never makes it easy
The new experiment might struggle to prove its immediate connection to practicality. But in a way, the preprint does adhere to Feynman’s advice. It’s certainly a theoretically robust demonstration of using quantum hardware to investigate quantum concepts.
At this very moment, that makes it seem detached from reality. Then again, when has anything quantum ever given easy answers? Yet, if science history is any guide, the best discoveries come from the most unexpected, seemingly impractical pursuits. We’ll just have to keep watch.
