What happens when the beauty of the quantum world collides with the power of literature? The Brilliant (Quantum) Poetry Competition dares poets from around the globe to explore just that. This unique international contest, created to celebrate the International Year of Quantum Science and Technology, invites everyone to express quantum science in verse.
Poet Richard Blanco. USDA Photo by Lance Cheung.
Hosted virtually by The Brilliant Poetry Project, the call for submissions opened on March 21 this year and will close next week on June 30. Winners will be announced on November 10. In this framework, and to help inspire quantum enthusiasts, poet and engineer Richard Blanco shared his “stereoscope or contrapuntal poem,” Uncertain-Sea Principle, inspired by the quantum uncertainty principle introduced by Werner Heisenberg, one of the scientists who helped develop quantum mechanics 100 years ago. The author remarks that it can be read “in more than one way, such as left to right across the two columns or down first one column and then the other.”
Note: To read the poem from left to right across both columns, it must be opened on a desktop (laptop).
Uncertain-Sea Principle
after Werner Heisenberg
the more I try to measure x
the more I know where I am
I scribble my name across the sand
the more I know where I’m going
the ebb of each wave seduces me
the more I know how to get there
freighter lights burn on the horizon
like candelabras floating toward port
the more I know when I’ll arrive
the tide rises on cue to kiss the shore hello
the less I try to solve for y
the less I know where I am
rustling palms protest losing
their green to the darkness
the less I know where I’ve been
the ocean vanishes into the midnight sky
the less I know who I can be
there’s no horizon in the stark night
the less I know who I am
I erase my name with a wave of mypalm
the more I try to determine my I
the less I can measure y
the less I know where I’m going
the burnt-orange moon rises, cools, disappears
the less I know how to get there
silhouettes of sailboats sleep till morning
the less I know when I’ll arrive
sea oats sway to the wind’s pitch
like inverted pendulums of timelessness.
the less I know where I am
seagulls abandon the sea every night
the more I can solve for x
the more I know where I’ve been
the sea gives and gives itself to the shore
yet returns again and again to itself
the more I know who I can be
the midnight sky vanishes into the ocean
the more I know who I am
even in the dark my eyes shape clouds
the more I know that I am, here
I clutch a fistful of sand, breathe, listen
the less I can determine my self
Listen to the poem below, read by the author in the video
Interview with Claudia Zendejas-Morales, A driving force behind quantum computing in Mexico and Latin America, developer of the Tequila programming platform, mentor at QWorld, and IBM Qiskit Advocate
Imagine a machine capable of solving problems that would take even the world’s most powerful supercomputers longer than the age of the universe to crack. As fantastical as it sounds, that’s one of the superpowers promised by emerging quantum technologies. And these technologies—like quantum computing—are starting to leap from labs to industry. In Mexico, serious strides are already being made to be part of this transformative future.
One of the pioneering scientists leading the way is physicist and computer engineer Claudia Zendejas-Morales. Her academic journey began in software engineering, but it was a quantum mechanics course that sparked her passion for quantum computing. Since then, she has built a solid academic and professional profile, participating in programs like USEQIP at the University of Waterloo, the Quantum Open-Source Foundation’s mentorship program (where she collaborated with The Matter Lab at the University of Toronto), and the IBM Quantum Summer Schools.
“As a physics student, I took quantum mechanics and found the subject fascinating. In that first class, they introduced us to quantum computing, and I dove in. At my school, there was little to nothing about quantum computing, so I actively sought out ways to learn about it online. That’s how I connected with different people and institutions involved in quantum computing. From there, I’ve been actively participating in the field,” Claudia explains enthusiastically.
“Access to the internet has been essential—it’s what allowed me to train and participate as a developer and mentor in projects like the Quantum Open Source Foundation. That’s where I worked on the Tequila project, which eventually led to a publication in IoP Science.”
Promoting Quantum Education in Latin America
Alongside her own training, Claudia has made a massive effort to promote education in quantum technologies across Mexico and Latin America. She became a Qiskit Advocate (Qiskit is IBM’s quantum programming platform), and has collaborated with initiatives like Quantum Flytrap, Qubit by Qubit, and QWorld. Always focused on Spanish-speaking students, she has developed educational content, translated Qiskit documentation into Spanish, and coordinated quantum computing courses at the National Autonomous University of Mexico (UNAM). She’ll soon join the University of Copenhagen’s Quantum Information Science program.
“A few years ago, there was nothing—now there’s something growing little by little. Thanks to people like Alberto Maldonado, we’ve kickstarted quantum computing in Mexico and created a community. He organized the first Qiskit Fall Festival in 2021, and we’ve held one every year since. Through him, I connected with a professor from another state working in quantum, and I reached out to folks at UNAM’s engineering faculty who were also interested. That’s how the community in Mexico has grown—we’re organizing more and more quantum events.”
QClass 23–24: A Game-Changing Experience
One of Claudia’s most rewarding experiences was organizing QClass 23–24, a free, advanced two-semester program in quantum computing for students from a wide range of backgrounds.
“What gave me the most satisfaction was coordinating a QWorld event called QClass 23–24. We ran postgraduate-level courses for two semesters. I was not only a mentor but also a professor—I designed the exams and course content using Qiskit. More than 1,500 students from over 100 countries and diverse professional backgrounds participated. It was incredibly rewarding—and all of it was free, because that’s the goal: to support others.”
A Quantum Network for Mexico
More recently, Claudia co-organized a national event alongside Dr. Alberto Maldonado and other collaborators, bringing together students, teachers, researchers, and industry professionals to collaborate, learn, and unlock new opportunities in quantum computing. Remarkably, the entire event was held in Spanish and prioritized inclusion.
A major barrier to learning quantum computing in Latin America is language—most resources are in English, and the concepts are already difficult. The event focused on creating learning spaces in Spanish, with accessible, clear explanations. As detailed in a paper published by IEEE, over 76% of participants—many without prior experience—felt confident diving into quantum computing thanks to this approach.
The attendee pool was highly diverse: undergraduates, master’s students, high schoolers, professors, professionals, and even public-sector workers. Over 40 universities were represented, some from outside Mexico. Women and non-binary people participated actively, highlighting the importance of diversity in scientific spaces.
One key goal of the event was to build a collaboration network between universities, research centers, and tech companies. That network is now a growing reality, with institutions like UNAM’s CECAv, the Autonomous University of Puebla (BUAP), Tecnológico de Monterrey, and companies like IBM Quantum, Xanadu, Quantinuum, and the Unitary Fund involved.
“Thanks to the network, our summer school at the engineering faculty now draws hundreds of attendees. We’re reaching more people and training more minds. The network and school are growing—it’s exciting to see. More students are getting interested, and some are even planning to write their thesis on quantum computing.”
Building a Quantum Community with Qiskit
Claudia’s journey with Qiskit perfectly illustrates how early access to educational tools can ignite passion and lead to meaningful contributions in a global tech community. What began as curiosity grew into mentorship, leadership, and major contributions to Spanish-language content.
“I primarily learned quantum computing through Qiskit, especially at the beginning. IBM did a great job promoting their platform and hosted events like the summer school, fall festival, and the Advocate program. I started as a participant, then became part of the staff. I became a Qiskit Advocate and began mentoring and translating materials into Spanish—tutorials, textbooks, programming notebooks. That led me to join the core localization team and get deeply involved.”
Woman. Latina. Scientist. Facing Challenges and Winning
Alongside her academic and technical achievements, Claudia has faced challenges rooted in gender and origin. Being a woman from Latin America has meant dealing with bias and discrimination. Her story highlights a persistent issue in STEM: the need to constantly prove yourself, being ignored in collaborative spaces, or judged for your name or nationality.
“This has been clear to me since the beginning: being a woman often means your knowledge isn’t considered sufficient or valid—especially by some men. I’ve seen it happen to other women, too. We have to work twice as hard to be heard or recognized as capable.”
“I’ve been rejected just for being a woman. At some hackathons, I tried joining teams but got no response. Then I’d see how the groups formed—and it was clear gender played a role.”
“Being Latin American adds to it. I’ve noticed people reacting to my surname or to the fact that I’m Mexican. Sometimes I even avoid saying where I’m from because people immediately form a limited idea about my abilities. Some don’t even know where Mexico is, but they still judge.”
Despite these hurdles, Claudia has found ways to turn exclusion into motivation. A great example is her second-place finish at a hackathon organized by Zaiku Group Ltd., where she and her team dotQ developed a hybrid quantum–classical model for genomics. This win wasn’t just technical—it was a statement against prejudice.
Final Thoughts: Feed Your Curiosity
After years of building pathways for quantum computing in Mexico and facing structural barriers, Claudia Zendejas-Morales offers this advice:
“I tell young girls to get into quantum computing. A lot of people hear the word ‘quantum’ and get scared without really knowing what it’s about. But the key is to dive in. Fortunately, there are now many entry points at different levels.”
“If you don’t know physics—you can learn. If you can’t code—you can learn. If you don’t speak English—that too can be learned. What matters is not ignoring your curiosity. Follow it. Explore. Seek answers.”
Mexico is planting the seeds for a solid, collaborative, globally connected quantum community—and anyone can be part of this technological era.
Quantum science has long held the promise of exponential speed and power, manipulating the properties of particles at the smallest scale to perform tasks in computing, sensing, and network communications.
At the University of Calgary, a quantum research and innovation ecosystem is focused on quantum-enabled solutions to real-world challenges. Support for quantum startups, industry partnerships, and next-generation talent is accelerating the development of commercial products that are now coming through the pipeline.
“We are finding solutions to problems using quantum technology,” says Shabir Barzanjeh, an associate professor in the Faculty of Science at UCalgary. He came there from Europe five years ago, drawn by the startup package and supportive environment the university offered, allowing him to make the leap from quantum theory to practical, market-ready applications.
Today, Dr. Barzanjeh is the scientific advisor of QuantaSense Inc., a company he co-founded with three UCalgary students, which is developing quantum amplifiers for use in devices such as ultra-sensitive microscopes that operate at low power.
The university has a 30-year history of quantum research, from foundational science to technology creation through such research-based startups, a key step in building Alberta’s quantum-enabling infrastructure.
“UCalgary is as close to ideal as you can get from a founder’s perspective,” says Jordan Smith, who graduated from the university with a bachelor’s degree in business and entrepreneurship, became a serial entrepreneur, and then returned there to pursue his lifelong interest in physics, with a goal of using frontier technologies to improve the world.
While completing bachelor’s and master’s degrees in physics, he co-founded Quantized Technologies Inc. (QTi) along with Daniel Oblak, an associate professor in the Department of Physics and Astronomy. Dr. Oblak is chief scientist and Mr. Smith is CEO of QTi, which has developed an advanced quantum encryption device to secure communications networks.
“We’ve got customers lined up to test, pilot and purchase our product,” says Mr. Smith, noting that QTi’s long-range objective is to build a quantum repeater, which is essential for enabling the backbone of the future quantum internet.
“That would be a first in the world,” says Mr. Smith, noting that UCalgary “is one of the most favorable universities for inventors and for researchers,” especially as QTi has the commercial rights to intellectual property generated on campus. “If you don’t have that in place, it can really undermine a lot of spin-out opportunities.”
Dr. Barzanjeh says support from UCalgary and the way it operates have been “super helpful” in the development of QuantaSense, from its low equity stake in the company to the business workshops it provides. “This gives us the chance to build our own future.”
The quantum ecosystem includes the Institute for Quantum Science and Technology, a multidisciplinary group of quantum researchers; Quantum Horizons Alberta, a province-wide initiative to expand and apply quantum science; Quantum City, focused on quantum solutions adoption through industry programs, startup support, quantum-enabling infrastructure, expert guidance and industry partnerships; and the Professional Master of Quantum Computing, which aims to upskill quantum graduate students and data scientists. UCalgary is also a supporting sponsor of the 2025 International Year of Quantum Science & Technology, marking 100 years of quantum mechanics.
Mr. Smith notes initiatives at UCalgary for quantum researchers looking to commercialize inventions include qHub, a “collision space” that allows new startups to interact. “Grad students just coming out of the lab have somewhere to go to get the ball rolling.”
Dr. Barzanjeh feels it’s important to expose students to quantum physics, even in high school and especially as undergrads, who will become the country’s next quantum experts.
“That’s where the quantum chain starts,” he says, which will then lead to commercialization in spin-out companies like QuantaSense and QTi. “If you have smart, directed people, you can make things happen.”
Featured Image: The quantum ecosystem at the University of Calgary is focused on finding quantum solutions to real-world challenges. Credits: Riley Brandt.
Well, the first point to make is that it would be unusual to find someone with a quantum scientist title or some academic degree in “quantum science.” Since quantum science has such wide applicability, it’s used by lots of different fields of science, such as chemistry, physics, and many types of engineering. People usually get academic degrees in these types of fields, but are learning some quantum science while doing so. If a person gets a degree in chemistry and ends up using a lot of quantum mechanics in their work, they might be identified as a “quantum chemist.”
So, are there also “quantum physicists” and “quantum engineers”?
You won’t usually encounter people with these titles, even though quantum understanding is essential to both physics and engineering. In the case of physics, most physicists use quantum science in their work, some sparsely and some intensively – this is true for subfields ranging from astronomy and astrophysics to condensed matter physics to particle physics. Engineering disciplines where you’ll frequently encounter quantum science include electrical engineering, materials science, chemical engineering, and mechanical engineering.
And are there different subfields of chemistry that use quantum mechanics besides quantum chemistry?
Absolutely. Almost all chemists are concerned with the making and breaking of chemical bonds between atoms, and, among many other things, quantum mechanics underlies the rules of how bonds are made and broken. Some chemists will want to spend a lot of time understanding the quantum nature of bonds as part of their work, while others may not feel the need to. Someone who does biochemistry is less likely to spend time thinking about the things they work on in terms of quantum mechanics, while someone who does physical chemistry is more likely to.
Besides Chemistry, Physics, and Engineering, are there other scientific fields where people learn quantum science?
Yes, people in other physical sciences, like earth science and materials science, can require a quantum understanding of some things. As quantum mechanics can be viewed as a general theory of information, there’s increasing interest in it in computer science as well. This interest is also related to the development of new technologies like quantum computers, which is also an area where you’re starting to see people who identify as quantum engineers. There are also an increasing number of examples of people looking into whether quantum concepts are useful for biological systems.
I gather then that while there are few people who identify as quantum scientists, there are a lot of different types of scientists who use quantum science.
Yes! This is probably not that surprising since quantum mechanics is such a wide-ranging theory and is understood to be the ground rules for the physical world. You would expect that a theory that powerful would be useful for many different types of science. One useful thing about learning more quantum science is that it is knowledge that you can take with you if you go from one field to another.
Written by Paul Cadden-Zimansky, Associate Professor of Physics at Bard College and a Global Coordinator of IYQ.
IYQ mascot, Quinnie, was created by Jorge Cham, aka PHD Comics, in collaboration with Physics Magazine. All rights reserved.
Interview with Dr. Alexia Auffèves, French physicist, pioneer of quantum energetics, and co-founder of the Quantum Energy Initiative (QEI).
Quantum physics has been the star of the tech world for almost a century now. However, a second quantum revolution is quietly emerging, shaking up the very foundations of how computers work at every level, from the principles behind the information itself and how the machines physically process it, to the algorithms. These new quantum technologies promise exceptionally faster computations and more secure communications.
As governments and industries invest heavily in quantum systems, it’s time to think about how we build and use them responsibly. That means not just focusing on what they can do but also on how much energy they use to accomplish tasks. Environmental and societal challenges recognized nowadays impose new constraints that were not obvious when classical computers first emerged. Early signs from quantum processors show lower energy consumption compared to traditional machines, but we don’t fully understand why and whether this advantage will persist as they scale.
In a seminal paper published on Physics Review X Quantum, in 2022, physicist Dr. Alexia Auffèves, First Class Research Director at CNRS in France, head of the International Research Lab MajuLab and invited Professor at the Centre for Quantum Technologies of Singapore argues that “a strong link between fundamental research and engineering is necessary to establish quantitative connections between quantum-level computing performance and energy consumption at the macroscopic, full-stack level.” In the framework of the International Year of Quantum Science and Technology, we had a conversation with Dr. Alexia Auffèves about her work as a pioneer of quantum energetics and as a co-founder and leader of the Quantum Energy Initiative (QEI) —an interdisciplinary effort that brings together experts in quantum physics, thermodynamics and energetics, computer science, and engineering aiming to understand how quantum technologies use energy from the ground up.
“I have been working in quantum thermodynamics for twelve years now, and at the beginning the impact of this research for quantum technologies was not easy to spot. The community of quantum thermodynamics was barely involved when the big takeoff in quantum technologies took place. I was part of the quantum thermodynamics community, but also had a vision of what was going on with quantum technologies because of my past as an experimentalist, and because I was running the Grenoble center for quantum technologies. So, I saw that there was clearly a gap to bridge between the two communities,” Alexia says.
Drawing lessons both from the history of classical computing and the recent developments in artificial intelligence, Auffèves reminds us that energy efficiency does not happen by accident: If you don’t search for it, you won’t find it. In the case of quantum computing, it may require decades of refinement, from understanding fundamental principles connecting energy cost and performance, to designing chips that balance performance with power consumption.
Creating an international research community to understand the energetic footprint of emerging quantum technologies
Motivated by the timeliness and relevancy of addressing the energy cost of quantum technologies, Alexia, her colleagues Robert Whitney and Janine Splettstoesser, and consultant and author Olivier Ezratty co-founded the Quantum Energy Initiative (QEI) in 2022.
That means establishing ways to measure energy efficiency in quantum devices, setting benchmarks, and identifying how to reduce energy consumption across different quantum platforms and computing paradigms. Quantum computing would be addressed first, but communication, and sensing, the two other so-called pillars of quantum technologies, would be investigated as well. The QEI team aims to define what “energy quantum advantage” really means in scientific terms and use that knowledge to guide smart design choices as quantum systems develop.
“The QEI is one of the first attempts to develop innovation in a finite world. In the past, innovators used to invest lots of money, hoping that something would come out. Now, we have to take into account the fact that the physical resources, especially energy, are finite. In that sense, quantum computing is growing in very, very different conditions than its older sister, classical computing, when there was oil all over the place, and so you could develop technologies presuming that we have infinite resources.”
But launching such initiatives, where fundamental science and emerging technologies intersect, also means navigating the influence of industry sectors, which often seek to align themselves with the prevailing ethical narratives of the time.
“When you launch an initiative like this, you are not really aware of the kind of forces it is going to trigger, especially nowadays, where there is a lot of quantum hype. If you mix this hype with the word “energy”, then it can quickly become unbearable. The QEI is not a greenwashing company. We are here precisely to prevent greenwashing. We are here to provide the community with objective scientific figures of merit so that sentences like: “Oh! My quantum computer will compute with less energy.” can be checked, and the energy efficiency of this very computer can even be compared to a fundamental bound and improved over time.
Can we build a theory that captures the quantum and the classical altogether?
To understand the true energy cost of quantum computing, we must look beyond hardware specifications and operational efficiency. At the heart of the challenge lies a much deeper, more conceptual problem: how to capture the quantum and classical worlds within a single physical model. This isn’t just a technical hurdle—it’s the oldest and still open problem of quantum physics, known as the measurement problem.
Any computation—whether classical or quantum—can be broken down into three stages: input, processing, and output. In quantum computing, both the input and the computational process involve inherently quantum phenomena such as superposition and entanglement. However, obtaining the result (the output) requires a measurement, a process that plays a central role in our understanding of quantum mechanics. Scientists remain puzzled by what exactly occurs during measurement, when quantum properties are seemingly lost as the quantum system interacts with the classical apparatus used to observe it.
“If you think about a quantum computer, while the computation is being performed, we deal with Schrödinger’s cat states, i.e. superpositions of states of “macroscopic” systems – here, data registers made of large numbers of qubits. So, there you have Schrödinger’s cat states in a box (a cryostat, for instance) that you are trying to control from the external [classical] world. And my feeling is that the truly fundamental energy cost of quantum computing is actually the cost of the box surrounding the Schrödinger’s cat.
Answering that question is hardware-independent and would also be a way to solve one of the biggest open questions of quantum physics: can we build a theory capturing the quantum and the classical altogether?
Nowadays, this question belongs to the field of quantum foundations, which is largely decoupled from quantum technologies where ‘Shut up and calculate’ [the answer usually given by engineers and academics to people wondering on the philosophical meaning of quantum theory] has been proven an efficient strategy; However, if you really want to calculate minimum energy costs and get a universal framework to benchmark all possible quantum platforms, solving that fundamental problem is highly relevant. This is a beautiful example of how the answer to foundational issues can be triggered by technological questions, just like the thermodynamic arrow of time came out from the optimization of heat engines,” Dr. Auffèves enthusiastically explains.
Quantum energetics at the forefront of the fundamentals of quantum physics itself
Peeling back the layers of abstraction to understand what’s really happening inside a quantum computer is foundational to asking deep questions about the nature of energy, noise, and computation at the quantum level. Alexia reflects on how her investigation offers a window into that philosophical and scientific inquiry, one that challenges us to rethink what “energy cost” means in the quantum world.
This is research driven by curiosity, not utility, by the desire to grasp what quantum energetics truly means at its core.
“My research is about understanding the fundamental mechanisms ruling flows of energy, entropy and information at the quantum level, and how these behaviors scale up to the macroscopic level. This research line dubbed quantum energetics is young, fundamental and it has an intrinsic value, out of any technological considerations. It is very important to underline that the QEI does not only promote a technologically-driven research. We also foster this fundamental core of quantum energetics. It is curiosity-driven and has triggered a number of exciting new questions lately, like measurement-powered engines where looking at a quantum system is enough to put it in motion!”
Dr. Alexia Auffèves kindly explains what quantum energetics is.
“It is inspired by classical thermodynamics, whose first motivation is to turn ‘messy energy’ (heat) from hot baths into a useful, controllable one (work). That is called a heat engine, and thermodynamics tells us what is its maximal efficiency, which is a fundamental bound. A second motivation is to reverse natural heat flows, which has a work cost: this is called a fridge, and it also has a fundamental bound. Now, what plays the role of the heat in quantum physics is quantum noise (like decoherence), which comes from the coupling to baths which do not necessarily have a well-defined temperature. This is why I talk about quantum energetics and not quantum thermodynamics (where temperatures play a central role). One of the purposes of the field is to derive quantum fundamental bounds: find the minimum energy cost for any kind of quantum process, for any kind of quantum noise. We want to relate irreversibility and energy waste in the quantum realm, where there is no temperature in the picture. This line of investigation is all about understanding the fundamentals of quantum physics with energetic and entropic probes.”
While much of quantum research today is driven by the race to innovate and commercialize, there remains a quieter, deeper pursuit—one that asks foundational questions about the nature of energy, noise, and irreversibility at the quantum level.
In a world increasingly shaped by energy concerns and climate imperatives, amazing women in science, such as Dr. Alexia Auffèves and the QEI, offer a roadmap for responsible innovation while pioneering fundamental research in quantum mechanics. It’s time to power the quantum future, with precision, purpose, and sustainability.
The quantum future doesn’t have to repeat the mistakes of the digital past. It can be better—if we start now.
Among all the inventions that quantum physics has produced, the laser holds a particularly important place, both for the rich story of successive discoveries that led to its birth, and for the role it has played in fundamental and applied research. I recall here the lineage of theoretical discoveries and experiments that have marked this history, restricting myself to the contribution of lasers to blue sky science and leaving aside its well-known role in various domains of technology. This story started from advances in the old quantum theory, from Einstein’s theoretical description of stimulated emission to O. Stern’s experimental discovery of the spatial quantization of the electron spin. Nuclear magnetic resonance, atomic clocks, optical pumping, and masers followed, and the pace of discoveries accelerated with the appearance of the laser in 1960. This extraordinary light source has since enabled breakthroughs in fundamental physics and opened up fields of research that could not even have been imagined at the time of its birth. I was fortunate to begin my career in physics at this crossroad of atomic physics and optics. In this article, I give my personal view of the great adventures in fundamental research in which I participated as an actor or spectator, from the cooling and trapping of atoms by light to the physics of quantum gases of bosons and fermions, the manipulation of individual quantum particles, and quantum simulations. Many other areas of fundamental physics, which I will only mention briefly, owe their development to lasers, and further advances are still to be expected in the years to come.
Featured Image: An optical molasses: a cloud of cold sodium atoms fluoresces at the intersection of three pairs of red-detuned counter-propagating laser beams. The laser beam used for the Zeeman slowing of the atoms is visible above the horizontal molasses beam. (Courtesy of W. Phillips.)
A century ago, pioneering scientists, including Wolfgang Pauli, Werner Heisenberg, and Erwin Schrödinger, laid the foundational principles of quantum mechanics. To mark this milestone, the Editors of the Physical Review journals have curated a collection of landmark papers that shaped the field. The whole collection is accessible at this link.
The collection begins with the following editorial by Dagmar Bruß from Heinrich Heine University Düsseldorf.
Physical Review Letters’ Editorial
In this International Year of Quantum Science and Technology, we celebrate the centenary of quantum physics. The anniversary marks the theoretical developments—including Heisenberg’s and Schrödinger’s formulations of quantum mechanics—that swiftly unfolded starting in 1925, building on earlier seminal contributions that established essential quantum concepts [1–5].
One hundred years span about three human generations. Similarly, I view the last century of quantum physics as progressing through three consecutive but intertwined generations. The first quantum generation was an era of understanding and mysteries. The groundbreaking works of this period introduced a formal quantum-mechanical description of physical reality. At the same time, this era saw researchers trying to cope with the counterintuitive phenomena—including entanglement and the related nonlocality—resulting from the quantum formalism.
The second quantum generation was one of consolidation and applications. This era brought about the “first quantum revolution”—a series of technological breakthroughs that have made quantum effects a part of our daily lives. Lasers, magnetic resonance imaging, and integrated circuits are all examples of quantum-enabled technologies. Quantum theory also started to reshape fields such as chemistry, materials science, astrophysics, and cosmology. This period came with a gradual acceptance of the peculiar effects emerging in the quantum regime.
The characteristic feature of the third quantum generation is the link with information science. Having come to terms with quantum weirdness, scientists realized that the quantum world has great, inherent power for quantum information processing. Harnessing the quantum laws of nature, they devised ways to perform computing, communication, simulation, and sensing with unmatched efficiency and security. Efforts to implement these disruptive technologies lie at the heart of contemporary research.
This collection brings together papers playing a foundational role within each of these three quantum generations. In the first generation, the development of the theory [6–17] went hand in hand with the discussion of doubts, paradoxes, and possible interpretations of quantum mechanics [18–22].
During the second quantum generation, pioneering contributions included insights into topological effects [23,24], as well as the conception of experiments for proving debated quantum-mechanical properties such as nonlocality [25–27], contextuality [28], and particle-wave duality [29]. These ideas were successfully tested in experiments when suitable technology became available [30–34].
The third quantum generation was opened up by papers that built the foundations of quantum information science. The “no-cloning theorem” [35] showed the possibility of achieving unbreakable security in quantum communication [36]. Other landmark papers pointed out the possibility of building a universal quantum computer [37] and of achieving a quantum computing advantage in practical applications [38]. In parallel to quantum information science, foundational research started to pursue new and alternative directions [39].
As we enter a new century of quantum science, we wonder how disruptive quantum information technologies will be, and on what timescales their full impact will be felt. But future quantum research will need to tackle much more than technology development. After 100 years of quantum mechanics, several fundamental issues remain partially or fully unresolved. Can we understand the boundary between the quantum and the classical world? How can the laws of classical thermodynamics emerge from quantum mechanics? Can gravity be quantized, and how can experiments look for signatures of quantum gravity? Many more questions will arise that we cannot even imagine today.
Certainly, research on foundational aspects of quantum physics will be as necessary in the future as it was in its first century. And as history has amply shown, so-called “quantum leaps” in technology are by and large the fruit of fundamental advances.
George E. Uhlenbeck and Samuel Goudsmit, Ersetzung der Hypothese vom unmechanischen Zwang durch eine Forderung bezüglich des inneren Verhaltens jedes einzelnen Elektrons, Zuschriften Und Vorläufige Mitteilungen 13, 953 (1925).
Albert Einstein, Boris Podolsky, and Nathan Rosen, Can quantum-mechanical description of physical reality be considered complete?, Phys. Rev. 47, 777 (1935).
Niels Bohr, Can quantum-mechanical description of physical reality be considered complete?, Phys. Rev. 48, 696 (1935).
Daniel M. Greenberger, Michael A. Horne, Abner Shimony, and Anton Zeilinger, Bell’s theorem without inequalities, Am. J. Phys. 58, 1131 (1990).
Lucien Hardy, Nonlocality for two particles without inequalities for almost all entangled states, Phys. Rev. Lett. 71, 1665 (1993).
Simon Kochen and Ernst Specker, The problem of hidden variables in quantum mechanics, J. Math. Mech. 17, 59 (1967).
John A. Wheeler, The “past” and the “delayed-choice” double-slit experiment, Mathematical Foundations of Quantum Theory, edited by A. R. Marlow (Academic Press, New York, 1978), pp. 9–48, 10.1016/B978-0-12-473250-6.X5001-8.
Stuart J. Freedman and John F. Clauser, Experimental test of local hidden-variable theories, Phys. Rev. Lett. 28, 938 (1972).
Alain Aspect, Jean Dalibard, and Gérard Roger, Experimental test of Bell’s inequalities using time-varying analyzers, Phys. Rev. Lett. 49, 1804 (1982).
X. Y. Zou, L. J. Wang, and L. Mandel, Induced coherence and indistinguishability in optical interference, Phys. Rev. Lett. 67, 318 (1991).
Vincent Jacques, E Wu, Frédéric Grosshans, François Treussart, Philippe Grangier, Alain Aspect, and Jean-François Roch, Experimental realization of Wheeler’s delayed-choice gedanken experiment, Science 315, 966 (2007).
B. Hensen et al., Loophole-free Bell inequality violation using electron spins separated by 1.3 kilometres, Nature (London) 526, 682 (2015); Marissa Giustina et al., Significant-loophole-free test of Bell’s theorem with entangled photons, Phys. Rev. Lett. 115, 250401 (2015); Lynden K. Shalm et al., Strong loophole-free test of local realism, 115, 250402 (2015).
Charles H. Bennett and Gilles Brassard, Quantum cryptography: Public key distribution and coin tossing, Proceedings of the International Conference on Computers, Systems & Signal Processing (1984), Vol. 1, pp. 175–179.
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We’ve talked about what quantum means, but what does “quantum mechanics” mean?
Quantum mechanics is a very general set of rules governing the physical world that was developed starting in 1925. The year 2025 was chosen as the International Year of Quantum Science and Technology because it marks 100 years of quantum mechanics. We’ve talked elsewhere about what quantum means; the mechanics part refers to a systematic set of rules that can be widely applied to describe how things move and change.
Do “quantum mechanics” and “quantum theory” mean the same thing?
These terms are often used interchangeably, but a conceptual and historical distinction can be made between them. Historians usually trace the beginning of quantum theory to the year 1900. This is the first time a quantum hypothesis—in this case, that energy came in countable pieces—was introduced in trying to understand a physical phenomenon. It became clear this was a useful hypothesis, but there was disagreement at the time about what its physical significance was. In the period from 1900 to 1925, other physical phenomena were explained using this and other quantum hypotheses. This was a period of quantum theory, sometimes now called the “old quantum theory,” but it was before there was quantum mechanics.
Then what changed to go from quantum theory to quantum mechanics?
In the 1900-1925 period, there was no consistency in how and when to apply these quantum hypotheses to explain experiments and make predictions. Sometimes they seemed to work spectacularly well, which gave many people confidence that there must be something to the idea. But many other times, scientists tried to use these hypotheses to model or predict things, and the model didn’t make any sense, or the predictions were wrong. The point is that there was no systematic way of applying quantum theory ideas to different physical systems. A systematic method would be a “mechanics.”
And this systematic method was developed in 1925?
The groundwork for it, yes. The basic framework and some general sets of principles to follow took a few years to sort out in order to be able to apply them systematically to a wide range of problems. People are even now still working to revise and extend this framework, but many of the core pieces of quantum mechanics were put in place in 1925. The term “quantum mechanics” started to be widely used in the 1920s to describe these systematic rules. It was also a phrase that distinguished this new mechanics from what’s now called “classical mechanics.”
What is “classical mechanics”?
Classical mechanics, or sometimes just “mechanics,” is the framework for describing the motion of massive objects that was initially developed in the 17th century. This framework is a set of general rules that can be used to describe how planets orbit the sun or the rate at which a dropped object falls to the ground.
These would be ideas like “to every action, there is an equal and opposite reaction” and other rules of motion?
Yes, exactly. The rules of classical mechanics are still very useful and often easier to use than those of quantum mechanics, but quantum mechanics is an even broader theory that, in many scientists’ assessments, supersedes the rules of classical mechanics. One way to put it is that by the end of the 19th century, scientists thought they had a good, systematic theory for how matter moved around—that’s classical mechanics—and a good, systematic theory for how light worked—this is the electromagnetic wave description of light. However, there were a number of puzzles in trying to understand how light and matter interact with each other. In the period from 1900 to 1925, some of these puzzles seemed to be solved using quantum ideas, but there was no systematic understanding of how light and matter interacted in all cases.
And quantum mechanics provided a systematic way for understanding how light and matter interact?
Not only did quantum mechanics provide a full description of how light and matter interact, but in doing so, it dramatically revised our understanding of light and matter and the rules governing each of them. The earlier “classical” rules governing matter and light were revealed to be only approximations of a richer, quantum description of matter, light, and their interactions.
Written by Paul Cadden-Zimansky, Associate Professor of Physics at Bard College and a Global Coordinator of IYQ.
IYQ mascot, Quinnie, was created by Jorge Cham, aka PHD Comics, in collaboration with Physics Magazine. All rights reserved.
The DPG is launching the online resource “A History Wall of Quantum Physics” as part of the International Year of Quantum Science and Technology
(DPG is an IYQ sponsor.)
The Deutsche Physikalische Gesellschaft (German Physical Society | DPG) has launched a website that offers insights into the multi-layered history of quantum physics. The website quantum-history.org uses a visual approach to the development of quantum physics and quantum mechanics in particular, whose historical development, like the theories and experiments themselves, is complex. The website offers both English-language and German-language versions.
Interested parties can now explore quantum physics online: from terms and concepts, theories and interpretations, to instruments, experiments, and measurements. Visual elements are combined with short texts or “history snacks” that explain the physical background and historical context as concisely and easily understandable as possible.
“Instead of people, their memories and views, the focus here is on physics itself,” explains project leader Arne Schirrmacher. “The history is presented visually: through curves, formulas, drawings, notes, and diagrams that represent the key advances, but also by photos and quotes that explain the context and conflicts in the development of quantum physics.”
Physics historians and physicists interested in the history of physics have intensively studied the history of quantum theory over the last two decades. The Quantum History Project made a significant contribution between 2006 and 2012, bringing together an international group of researchers at the Max Planck Institute for the History of Science and the Fritz Haber Institute of the Max Planck Society. This led to the establishment of a larger network of quantum historians that is still active today and has contributed to the History Wall.
“The future applications of innovations based on quantum physics are diverse, and their full range is not yet foreseeable,” says Klaus Richter, President of the German Physical Society. “In Germany, the International Quantum Year is therefore also being celebrated under the motto ‘100 years is just the beginning’.”
The “Quantum History Wall” was realized with the support of the Wilhelm and Else Heraeus Foundation and is a contribution of the DPG to the International Year of Quantum Science and Technology. Further thanks go to the participating publishers and institutions, such as the American Physical Society, the Heisenberg Society, the Deutsches Museum, Wiley-VCH, Hirzel, Springer Nature and others for generously granting free usage rights to numerous archival materials and photographs.
The History Wall is currently also part of the special exhibition “Was zum Quant?!”, which is under the umbrella of the DPG and on display in the Forum Wissen, the Museum of Knowledge of the University of Göttingen, until October 2025.
LONDON – April 28th, 2025 – UNESCO’s 2025 2025 International Year of Quantum Science and Technology (IYQ) today announces the launch of the Quantum 100: A global snapshot of careers & community, a major global initiative to celebrate the diverse people behind quantum science and technology.
From researchers to policymakers, educators to entrepreneurs, and students to communicators, The Quantum 100 will recognize and champion 100 quantum professionals from around the world.
To be considered for inclusion, IYQ is asking for submissions which demonstrate important contributions to quantum science and technology or the quantum community in the fields of:
Academia
Arts
Communication
Education
Government
Industry
Philanthropy
Submissions are open from today until 28th May.
Each person within the Quantum 100 will have their name and photo in an online gallery on the IYQ website with details about their accomplishments. Submissions will be reviewed by members of the IYQ Steering Committee, an international consortium of scientists and policymakers, with announcements of the Quantum 100 beginning on 29 July, to coincide with 100 years since the publication of Werner Heisenberg’s “magical” paper that led to the development of the new model of quantum mechanics.
“The Quantum 100 is in the true spirit of the IYQ ,” said Sir Peter Knight,
Professor at Imperial College London, Chair of the Quantum Metrology Institute at the National Physical Laboratory and co-chair of IYQ Steering Committee. “ Quantum sciences and the wider quantum community is driven forward by a cohort of diverse, globally-minded individuals. With this initiative, we will celebrate the roles and contributions of these individuals, and in doing so inspire the next generation of quantum talent. One of the goals of IYQ is that anyone, anywhere can participate, and the Quantum 100 is a timely reminder of how many different kinds of people are already participating and thriving in the quantum industry around the world.”
Silvina Ponce Dawson, President of IUPAP (International Union of Pure and Applied Physics) added:
“With diversity key to scientific endeavour, The Quantum 100 represents an important and timely initiative to highlight how quantum science and technology can be tackled from different perspectives. I truly hope that Quantum 100 will inspire other activities and help increase diversity within a field that is already exerting a huge impact on human society worldwide.”
About the International Year of Quantum Science & Technology:
The UN declared 2025 the International Year of Quantum Science & Technology (IYQ) to mark the 100th anniversary of the study of quantum mechanics, and to help raise public awareness of the importance and impact of quantum science and applications on all aspects of life. It also aims to inspire the next generation of quantum scientists and improve the future quantum workforce by focusing on education and outreach. Anyone, anywhere, can participate in IYQ by helping others to learn more about quantum or simply taking the time to learn more about it themselves.
