Physics

Professor John Cumalat wins 2025 Hazel Barnes Prize

Rachel Sauer — Fri, 11 Apr 2025 22:19:58 +0000

Professor John Cumalat wins 2025 Hazel Barnes Prize Rachel Sauer Fri, 04/11/2025 - 16:19

Cumalat ‘literally re-shaped our understanding of the fundamental particles making up the known universe,’ colleagues note

John Cumalat, professor of distinction in the University of Colorado Boulder Department of Physics, has been awarded the 2025 Hazel Barnes Prize.

Established in 1991 by former chancellor James Corbridge to honor the late Hazel Barnes, ��Ҵ�ý�ƽ�� professor of philosophy from 1953-86, the $20,000 Hazel Barnes Prize celebrates the enriching interrelationship between teaching and research and is the largest and most prestigious award funded by the university.

“Professor Cumalat is an exemplary educator and researcher whose contributions to his students, this university and the field of physics are highly deserving of recognition,” said Chancellor Justin Schwartz. “His selection as the Hazel Barnes Prize winner reflects his dedication and ingenuity, and I am so proud of all the ways he utilizes these qualities in service to ��Ҵ�ý�ƽ�� and to humanity.”

Cumalat completed his PhD in physics from the University of California Santa Barbara in 1977 and his postdoctoral work with Fermilab in Batavia, Illinois, in 1979. Since joining the ��Ҵ�ý�ƽ�� physics faculty in 1981, he has garnered multiple honors, including the Best Should Teach Award in 2003, the Robert L. Stearns Award in 2010 and the BFA Excellence in Service Award in 2013. He became a professor of distinction in 2014.

“John is an educator in the broadest sense and has had a lasting impact on his students and colleagues. He leads by example, he leads from the front, and he leads with integrity and compassion.”

Best known for his research in particle physics and for his development of state-of-the-art particle-detector technology and instrumentation, Cumalat is a member of five professional organizations: Sigma Xi, the American Association for the Advancement of Science, the American Association of Physics Teachers, the American Astronomical Society and the American Physical Society.

He is also a member of the Compact Muon Solenoid experiment at the Large Hadron Collider at CERN, the current principal investigator of the CU High Energy Physics Department of Energy Grant and the principal investigator of the Professional Research Experience Program with the National Institute of Standards and Technology.

Cumalat has authored or co-authored more than 1,500 publications and has been cited nearly 200,000 times, according to INSPIRE, an online hub that collects scholarly work in the field of high-energy physics. He has also served on several dozen graduate-student committees and on approximately 150 undergraduate-student thesis committees.

In their letters supporting Cumalat’s nomination for the Hazel Barnes Prize, several of his colleagues noted the significance of his contributions to the field of physics.

“John Cumalat has literally re-shaped our understanding of the fundamental particles making up the known universe,” wrote ��Ҵ�ý�ƽ�� Professor of Physics James Nagle. “His research focuses on the fundamental building blocks of matter and his leadership has led to critical advances in our understanding of quarks as well as the discovery of the Higgs boson.”

“John is one of the very best physicists that I know,” said Joel Butler, a distinguished scientist at Fermilab. “He is well-known and greatly respected throughout the U.S. and in the world. I consider it one of the most fortunate aspects of my own career that I have had this long and productive association with him.”

Other colleagues brought attention to Cumalat’s role in expanding and improving physics education at ��Ҵ�ý�ƽ��.

“John’s leadership was critical in the expansion of the number of physics degrees in the College of Arts and Sciences,” said ��Ҵ�ý�ƽ�� Professor of Physics Paul D. Beale. “I believe that John’s most important and lasting contribution to teaching and learning is his leadership in expanding the number of physics students engaged in undergraduate research, especially conducting honors research projects with members of the physics faculty and other scientists and engineers.”

“John is an educator in the broadest sense and has had a lasting impact on his students and colleagues,” said Patricia Rankin, former physics professor at ��Ҵ�ý�ƽ�� and current chair of the Physics Department at Arizona State University. “He leads by example, he leads from the front, and he leads with integrity and compassion.”

“I am honored to be selected by previous Hazel Barnes winners as the 2025 Hazel Barnes Prize winner,” says Cumalat. “I particularly value my colleagues in physics nominating me for the award and for soliciting external supporting letters from students and national and international colleagues. I am humbled by the entire process.”

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Cumalat ‘literally re-shaped our understanding of the fundamental particles making up the known universe,’ colleagues note.

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CU alum Stephen Koehler enjoys high-flying career

Rachel Sauer — Wed, 09 Apr 2025 18:14:40 +0000

CU alum Stephen Koehler enjoys high-flying career Rachel Sauer Wed, 04/09/2025 - 12:14

Bradley Worrell

The ROTC cadet and physics major turned naval aviator turned admiral was appointed commander of the U.S. Pacific Fleet in early 2024

University of Colorado Boulder grad Stephen T. Koehler (Phys’86) has a really, really big job.

How big?

It covers an area encompassing 100 million square miles—roughly half the earth’s surface—from Antarctica to the Artic Circle and from the western U.S. coast to the Indian Ocean. The job includes oversight of about 200 ships, 1,500 aircraft and 150,000 military and civilian personnel.

��Ҵ�ý�ƽ�� grad and U.S. Navy Admiral Stephen Koehler (Phys’86) was selected as the commander of the U.S. Pacific Fleet in April 2024, following a succession of leadership positions in the Navy.

Admiral Koehler is the commander of the U.S. Pacific Fleet, a position he assumed in April 2024 after a series of successive leadership positions during his 40-year career in the Navy. He became the 36th commander since Admiral Chester Nimitz assumed command on Dec. 31, 1941, at Pearl Harbor.

Koehler’s ascension to a top leadership post in the Navy is perhaps even more notable given that his initial goal was modest: He wanted to fly jets like his dad, who was a Navy fighter pilot.

“Honestly, I didn’t know I would stay in the Navy this long,” he says. “But from a very young age, I watched my dad go to work to fly airplanes and I just thought he was so cool, and I remember thinking, ‘I want to do what he does.’ My dad loved being a fighter pilot. So, I knew I wanted to fly jets and land them on ships.”

After being commissioned in 1986 through the Naval Reserve Officers’ Training Corps (ROTC) program at ��Ҵ�ý�ƽ��, Koehler became a naval aviator in 1989 and went on to fly more than 3,900 hours in the F-14 Tomcat and F-18 Hornet, with 600 carrier landings.

Koehler subsequently served in leadership positions that included commanding a fighter squadron, serving as the captain of a nuclear aircraft carrier, commander of a carrier strike group, commander of the U.S. Third Fleet and director for strategy, plans and policy for the Joint Staff in Washington, D.C., which was his last post.

Recently, Koehler spoke with Colorado Arts and Sciences Magazine about how his time at ��Ҵ�ý�ƽ�� helped him prepare for his career in the Navy, what it was like to be a naval aviator and what his job entails as commander of the U.S. Pacific Fleet. His responses have been lightly edited and condensed for space.

Question: Why did you decide to attend ��Ҵ�ý�ƽ��? And why did you choose to get your degree in physics?

Koehler: The main reason I ended up applying to ��Ҵ�ý�ƽ�� was that the summer before my senior year in high school, I was taking a Greyhound bus around the country, rock climbing with my cousin. We stopped in Boulder for a week and we stayed with this guy who was a friend-of-a-friend type thing. We climbed nearly every day.

One day it rained bad enough we couldn’t climb, so we heard there was a campus in town and we decided maybe we should walk around it. I picked up an application at the UMC (University Memorial Center), where it stayed in my backpack for the rest of the summer. Later, I filled it out and sent it in, and then I got accepted.

I saw CU had a physics major and it had ROTC, so I said, ‘I’ll give it a go.’

Admiral Stephen Koehler (right) with his father, who was also a naval aviator, following the younger Koehler’s commissioning in 1986 during a ceremony held at Old Main on the ��Ҵ�ý�ƽ�� campus.

I knew I wanted to be as competitive as I could going into Navy flight school. And initially, I thought I might want to be a test pilot—and I knew you had to have hard-science capability for that, so that’s why I majored in physics. I was not a natural physics guy, so it was a slog for me, but I did it to keep my options open.

Question: Do you feel like your time at ��Ҵ�ý�ƽ�� helped prepare you for entering the Navy?

Koehler: Yes. Certainly, the ROTC piece provided an understanding of the Navy even beyond what I learned as a child of a Navy parent, and it taught me about leadership.

The physics background proved very beneficial, not only for flight school, but it led to me being selected to be a nuclear-trained officer. There is a technical degree that’s required to do that, and so, yes, my time at CU set me up for that.

Question: When people think of naval aviators, they likely think of the movie Top Gun. What is it like to be a naval aviator in real life?

Koehler: People who watch Top Gun think you are all tan and spend your days playing volleyball at the beach, or they watch Top Gun: Maverick and think you’re all tan and you play football on the beach (laughs). And arguably, I would love to do some of that, but being a carrier-based fighter pilot is about being steeped in professionalism.

Naval aviators train and train so that they make the extremely difficult look easy and routine when it’s not. It takes skill to land a plane on a pitching (ship) deck, day or night, and it takes dedication to be a fighter pilot, to make sure that you are better than the adversary. It’s about having a warrior mindset and making sure you are good at it, because you’ve got to be better than your opponent.

Question: What is your call sign and how did you get it?

Koehler: It’s Web. I won’t go into the whole boring story, but it’s short for Webster’s Dictionary. I received it during a very public display for a lack of spelling prowess (laughs). And I’m actually not a bad speller, but I was on that day.

I wish it (the call sign) was for something cool, like ‘spiderweb,’ or ‘he’s on the web.’ That’s probably half the reason it stuck—because it sounds cool even though it’s not (laughs). …

Now, even at this level, people call me by that name instead of my (given) name. I was sitting in the situation room in the White House in my last job and people would call me Web—not Steve or Admiral Koehler. They would be like, ‘Hey, Web, what do you think about this?’ So, that’s just what ends up happening.

Question: How does one go from being a naval aviator to a command where you are responsible for hundreds of ships and planes and tens of thousands of sailors?

Koehler: So, it’s a process. The first step of it is staying in the Navy and being promoted to the command of a squadron, which is 12 planes and about 250 people. You’re evaluated and then there’s normally two paths after that. You either go the nuclear power route, which means you learn to drive aircraft carriers, or you stay in the air wing and you’re in command of an air wing on a carrier.

The U.S. Pacific Fleet (a portion of which is pictured here) encompasses 100 million square miles from Antarctica to the Arctic circle and from the west coast of the United States into the Indian Ocean. The U.S. Pacific Fleet consists of approximately 200 ships, 1,500 aircraft and 150,000 military and civilian personnel. (Photo: U.S. Navy)

I was chosen to go the nuclear power route, so my physics degree proved useful. I went to nuclear power school and then I was the No. 2 guy on an aircraft carrier, the USS Carl Vinson. I went on to command the USS Bataan, which is an amphibious assault ship, and then I was selected to be the captain of a nuclear aircraft carrier for two and a half years, which was the USS Dwight D. Eisenhower.

Pending your performance and time in service, you may be selected to the rank of rear admiral (or flag rank). If you are not selected, there’s mandatory retirement at 30 years.

I was selected after my command of the aircraft carrier and have progressed through operational and staff command that yielded additional flag rank promotions. There was a decision by Naval leadership at some point to promote me to full admiral and select me to be the Pacific Fleet commander. So, it was a natural progression, and I’m very honored to be here.

Question: Can you share the scope of your duties as Pacific Fleet commander and the role the position plays in the world today?

Koehler: The scope and scale of the Pacific Fleet, of the area I’m responsible for as far as naval interests, is from the coast of California to the west coast of India, and Antarctica to the Arctic. It’s a huge area. …

The Pacific Fleet command is of vital importance to national security, resulting from the economic ties and the commerce that travels on the ocean, for which I am responsible on the Navy side to be ready to respond. There’s just a real importance to the job and there’s a lot of work to do out there. We must continue to improve our position and capability to maintain and ensure the freedom of the seas. The intent is a ‘free and open Indo-Pacific,’ with freedom of commerce, sovereign rights and the ability to sail and operate in accordance with international law, and those things the Pacific Fleet works continuously to provide.

Question: What is the best thing about being Pacific Fleet commander? And what is the most difficult thing?

Koehler: The best thing is having the opportunity to lead all of these sailors. With sailors and civilians, there is on the order of 150,000 of them working toward a common goal, which is to achieve our national objectives. The opportunity to go out and see them and lead them is the best. That also delves into the challenge, which is that it’s a large scale and scope of operations that I oversee. The challenge is to be able to get out and see them as much as I would like and revel in the success they have. They are a pretty amazing group of people who do some outstanding work.

Admiral Stephen Koehler salutes during a 2024 ceremony at Pearl Harbor. (Photo: U.S. Navy)

Question: Do you still get to fly jets?

Koehler: I wish I did. I did get to fly as an admiral when I was the carrier strike group commander and we were on deployment in 2017. I got my last carrier landing in April of 2018.

Flying is a young person’s game. Not that I wouldn’t continue to go flying … but there’s no time to maintain my currency and while it would be fun for me, I’m not sure it would be the best use of my time now.

Question: With your four decades of service in the Navy, are there a few standout moments in your career?

Koehler: That’s a really hard one. First of all, it’s been 40 years, but it doesn’t seem like it. I got to Colorado (as a freshman) in 1982, and it feels like I was just there. …

There are all sorts of things I remember. Taking command of an aircraft carrier, with 3,000 people assigned to it, and with the air wing it’s 5,000 people. That was the first huge command for me, and you have all of these sailors that you get the privilege to lead.

Certainly, the news that I was going to be Pacific Fleet commander was memorable. That was something I would never expect. It’s the honor of a lifetime to do that, and to follow in the footsteps of some amazing people, starting with Admiral Nimitz in World War II.

Another standout thing was being the demonstration pilot for the F-14 at air shows and having the opportunity to fly in front of my family at the Miramar Air Show in 1996. It was an amazing day to fly for my dad that day.

Looking back, there are many memories, and it’s been nothing but a really fun, challenging, rewarding experience. I have been able to enjoy it with my wife, Gina, who’s been with me since college, where we met in 1983 in Boulder in the Baker Hall dorm. She’s been with me the whole time, which has just been amazing.

Question: Anything else you would like to add?

Koehler: Go Buffs!

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The ROTC cadet and physics major turned naval aviator turned admiral was appointed commander of the U.S. Pacific Fleet in early 2024.

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Top image: Admiral Stephen Koehler (green flight suit) was designated a naval aviator in 1989 and flew more than 3,900 hours in the F-14 Tomcat and F-18 Hornet, with 600 carrier landings.

Two ��Ҵ�ý�ƽ�� scientists win prestigious honor

Clint Talbott — Thu, 27 Mar 2025 14:00:00 +0000

Two ��Ҵ�ý�ƽ�� scientists win prestigious honor Clint Talbott Thu, 03/27/2025 - 08:00

Ivan Smalyukh and Tom Blumenthal are named fellows of the American Association for the Advancement of Science

Two University of Colorado Boulder professors have been named 2024 fellows of the American Association for the Advancement of Science (AAAS), the group announced today.

Ivan Smalyukh (left) and Tom Blumenthal

Ivan Smalyukh, professor of physics, and Thomas Blumenthal, professor emeritus of molecular, cellular and developmental biology (MCDB), are among the 471 scientists, engineers and innovators who have been recognized for scientifically and socially distinguished achievements by the world’s largest general scientific society and publisher of the Science family of journals.

This year’s class of fellows “is the embodiment of scientific excellence and service to our communities,” said Sudip S. Parikh, AAAS chief executive officer and executive publisher of the Science family of journals.

“At a time when the future of the scientific enterprise in the U.S. and around the world is uncertain, their work demonstrates the value of sustained investment in science and engineering.”

“I am pleased to see this well-deserved recognition of Professor Smalyukh and Professor Blumenthal. Their accomplishments highlight the remarkable scientific advances occurring at CU,” said Irene Blair, dean of natural sciences.

Smalyukh’s research encompasses different branches of soft-condensed-matter and optical physics, including chiral phenomena, knot theory, laser trapping and imaging techniques, molecular and colloidal self-assembly, fundamental properties of liquid crystals, polymers, organic and nano photovoltaics, nano-structured and other functional materials, as well as their photonic and electro-optic applications.

“We aspire to uncover very fundamental physical principles underpinning phenomena and properties of materials and other physical systems,” Smalyukh noted. “At the same time, we also apply this fundamental knowledge to contribute to a sustainable future via designing artificial forms of meta matter needed to reduce the growing energy demand and slow down climate change.”

Smalyukh earned BS and MS degrees with highest honors in 1994 and 1995 from Lviv Polytechnic National University in Ukraine. He earned a PhD in chemical physics in 2003 from Kent State University in Ohio.

He joined the ��Ҵ�ý�ƽ�� faculty in 2007. In addition to serving as a professor of physics, he holds a courtesy appointment as a professor in the Department of Electrical, Computer and Energy Engineering, is a fellow in the Materials Science Engineering Program and is a fellow of the Renewable & Sustainable Energy Institute (RASEI), a joint institute of NREL and ��Ҵ�ý�ƽ��.

Among other awards, Smalyukh has been named a fellow of the American Physical Society and has won the Department of Energy Early Career Research Award and a National Science Foundation CAREER Award.

Smalyukh said he is honored by the selection: “I am especially grateful to many students and postdocs doing interdisciplinary physics-centered research together with me over nearly 20 years at ��Ҵ�ý�ƽ��.”

Blumenthal’s lab has studied a variety of important problems in molecular biology, including regulation of gene expression, mechanisms of RNA splicing and arrangement of genes on chromosomes. His lab is responsible for discovering that eukaryotes can have operons for identifying the protein that is responsible for recognizing the 3’ splice site and for a variety of other esoteric findings.

He has also studied how the tiny extra chromosome responsible for Down syndrome changes the levels of many proteins, even though most of those proteins are not encoded on the extra chromosome.

Blumenthal earned a BA in biology from Antioch College in 1966 and a PhD in genetics from Johns Hopkins University in 1970. He did postdoctoral research at Harvard University from 1970-73, then spent 23 years at the Biology Department at Indiana University Bloomington and nine years at the University of Colorado School of Medicine. He joined ��Ҵ�ý�ƽ�� faculty in 2006 and served as professor and chair of MCDB.

Among other awards, Blumenthal was recognized as a fellow by the American Academy of Arts and Sciences in 2010 and won a fellowship from the John Simon Guggenheim Memorial Foundation in 1980.

Lee Niswander, professor and chair of molecular, cellular and developmental biology, said the department is thrilled about Blumenthal’s recognition. “Tom’s research program related to RNA processing and gene regulation, as well as his strong leadership of MCDB, have left an enduring mark on science and MCDB.

“Tom continues to engage with astute questions and the endowment of a lecture series related to RNA biology through a partnership between ��Ҵ�ý�ƽ�� and CU Anschutz.”

Counting Blumenthal and Smalyukh, 81 ��Ҵ�ý�ƽ�� professors have been named AAAS fellows since 1981.

Ivan Smalyukh and Tom Blumenthal are named fellows of the American Association for the Advancement of Science.

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Discovering Boulder County’s tiniest residents

Rachel Sauer — Mon, 24 Mar 2025 17:10:47 +0000

Discovering Boulder County’s tiniest residents Rachel Sauer Mon, 03/24/2025 - 11:10

Collette Mace

��Ҵ�ý�ƽ�� alum and experienced caver Dave Steinmann recently discovered a new species of pseudoscorpion in Mallory Cave, with a moniker honoring its namesake hometown

When Dave Steinmann (Phys’90) first started classes at the University of Colorado Boulder in 1984, he had never explored a cave before and never really thought much about caves. However, when his new dorm-mate suggested they try his dad’s favorite hobby of caving, what seemed at first like an adventurous new pastime soon turned into a lifestyle for Steinmann—one that he has continued for more than 30 years and leading to his discovery of almost 100 new cave-dwelling species.

Steinmann, now a research associate with the Denver Museum of Nature & Science’s Zoology Department, most recently discovered a new species of pseudoscorpion named after the city closest to where it was found—none other than CU’s hometown of Boulder. Steinmann said that he knew almost immediately that the critter that is now known as Larca boulderica was a new species.

Dave Steinmann (right) with his son, Nathan (left), and wife, Debbie (center), as they get ready to go caving. (Photo: Dave Steinmann)

When he first spotted it in Mallory Cave, one of Boulder’s most well-known cave systems thanks to its role in bat conservation, he immediately noticed its unique, almost lentil-shaped body and adaptations for cave living, such as its pale color. These specimens were later verified as a new species by Mark Harvey, a pseudoscorpion expert at the Western Australian Museum; Harvey and Steinmann recently published details of the discovery in ZooKeys.

Steinmann notes that it’s typically not difficult to discern when a specimen is a new species, as it happens pretty frequently in the ancient cave systems right below our feet.

“I always say that if I want to discover a new species, I just need to visit a new cave,” he says.

Why are caves such a great place to make new discoveries? The answer lies in their role as a sort of refuge from climate change, Steinmann notes. In caves, insects can hide from the effects of temperature, floral and faunal changes that happen more rapidly in the outside world, facilitating isolated evolutionary changes.

Changing cave life

However, even cave life is changing. Lately, the temperature inside of caves, typically very cold, has been observed to be rising on a minuscule scale. Although this may seem trivial, even a few degrees’ difference can have immeasurable effects on the delicate life structures within the caves.

Similarly, outside temperatures affect which species go in and out of the cave systems, most notably bats. With the recent spike in white-nosed syndrome in bat populations, the number of bats in cave systems has decreased dramatically, with disastrous effects on internal cave species such as Larca boulderica, who survive on organic material—most often wood brought into the cave—and guano (bat fecal matter).

These changes are slow to progress, though, and there is still time to save cave ecosystems like that of Mallory Cave, which is closed to the public to protect the bat population inside (although it’s still possible to hike up to the cave entrance, a pleasant and short hike for anyone hoping to get outside).

So, how did Steinmann spot these teeny tiny bugs who live on bat feces? Well, after more than 30 years of experience, he has some tricks up his sleeve. One of the easiest methods he uses to spot tiny critters is simply by turning over rocks or pieces of wood.

When species like pseudoscorpions are disturbed by the movement or sense the carbon dioxide released by human breathing, they tend to skitter in every direction, looking for a new spot to curl up and revel in the damp darkness. When they move around, according to Steinmann, it’s just a game of whether you can catch them quickly enough.

The newly described pseudoscorpion Larca boulderica is about the size of a sesame seed and is only known to live in Boulder, Colorado. (Photo: Dave Steinmann)

To catch samples, Steinmann usually brings simple tools along with him—a painter’s brush and some rubbing alcohol. When the brush is wetted with the alcohol, it’s easy to run it along a surface and pick up all of the tiny things residing there, including minuscule species of bugs like Larca boulderica.

From there, it’s also easier to see what he’s found, as cave species are usually albino due to the lack of melanin— they don’t need pigmentation when there’s no sunlight—and they stand out against the dark ground and hairs of the paintbrush.

Looking for a gold bug

Despite being at it for multiple decades, Steinmann has no plans to slow down his caving career any time soon. He’s even made it a family pastime, and often spends time caving with his wife, Debbie, and his son, Nathan. He keeps an ongoing list of caves he plans to visit in the future and looks forward to making even more discoveries.

“I’d really like to find some kind of gold-colored bug and name it after the university,” he says, “or maybe even Coach Prime!”

He’s also enthusiastic about getting more students involved in caving, including caver and photographer Andres “Andy” Better, who will be a CU transfer student next fall. Steinmann emphasized how many different opportunities lie in the caving experience and says students of any background could find a niche interest in the hobby.

He also mentions local groups and clubs for both new and experienced cavers, including the Front Range Grotto and the Colorado Grotto, which meets at the Colorado School of Mines. He says that while anyone is welcome in caving, experienced members of the clubs can sometimes be protective of the places they visit, as human disturbances can harm delicate cave ecosystems, and caving as a hobby can be dangerous in a lot of ways.

However, if you’re looking to learn about caving with curiosity and respect, any of these clubs are great ways to get involved in this adventurous and exciting hobby—just be careful not to step in the bat guano because there could be a new species in there!

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��Ҵ�ý�ƽ�� alum and experienced caver Dave Steinmann recently discovered a new species of pseudoscorpion in Mallory Cave, with a moniker honoring its namesake hometown.

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An ultrafast microscope makes movies one femtosecond at a time

Rachel Sauer — Tue, 11 Mar 2025 16:18:01 +0000

An ultrafast microscope makes movies one femtosecond at a time Rachel Sauer Tue, 03/11/2025 - 10:18

New ��Ҵ�ý�ƽ�� research harnesses the power of an ultrafast microscope to study molecular movement in space and time

The interactions in photovoltaic materials that convert light into electricity happens in femtoseconds. How fast is that? One femtosecond is a quadrillionth of a second. To put that in perspective, the difference between a second and a femtosecond is comparable to the difference between the second right now and 32 million years ago.

Subatomic particles like electrons move within atoms, and atoms move within molecules, in femtoseconds. This speed has long presented challenges for researchers working to make more efficient, cost-effective and sustainable photovoltaic materials, including solar cells. Imaging materials on the nanoscale with high enough spatial resolution to uncover the fundamental physical processes poses an additional challenge.

Understanding how, where and when electrons move, and how their movement depends on the molecular structure of these materials, is key to honing them or developing better ones.

Ultrafast nano-imaging of structure and dynamics in a perovskite quantum material also used for photovoltaic applications. Different femtosecond laser pulses are used to excite and measure the material. They are focused to the nanoscale with an ultrasharp metallic tip. The photo-excited electrons and coupled changes of the lattice structure (so called polarons, red ellipses) are diagnosed spectroscopically with simultaneous ultrahigh spatial and temporal resolution. (Illustration: Branden Esses)

Building on more than five years of research developing a unique ultrafast microscope that can make real-time “movies” of electron and molecular motion in materials, a team of University of Colorado Boulder scientists published in Science Advances the results of significant innovations in ultrafast nanoimaging, visualizing matter at its elementary atomic and molecular level.

The research team, led by Markus Raschke, professor of physics and JILA fellow, applied the ultrafast nanoimaging techniques they developed to novel perovskite materials. Perovskites are a family of organic-inorganic hybrid materials that are efficient at converting light to electricity, generally stable and relatively easy to make.

Working with a thin perovskite layer, the researchers directed ultrashort laser pulses onto tiny metallic tips positioned above the perovskite layer. The tip functions like an antenna for the laser light and focuses it to a spot much smaller than what is possible in conventional microscopes. The tip is then scanned across the perovskite layer, creating an image pixel by pixel. Each image provides one frame of a movie as the different laser pulses are varied in time.

The movie also has “color,” albeit in the infrared and invisible to the human eye but where the molecules and electrons respond. Through different wavelengths of light, the researchers can follow both the electron and molecular motion and their coupling, which is what controls the photovoltaic efficiency in perovskites.

This milestone not only helps them better understand the missing links between the perovskite’s crystal structure and composition and its performance as a photovoltaic material but also led to the surprising discovery that more disorder seems to facilitate better photovoltaic performance.

“We like to say that we’re making ultrafast movies,” Raschke says, adding that there have long been many unknowns about the elementary processes after sunlight gets absorbed in photovoltaic materials and how the excited electrons move in them without being dispersed, but “for the first time, we can actually sort this out because we can record spatial, temporal and spectral dimensions simultaneously in this microscope.”

Molecules as spectators of how the electrons move

In recent years, much research has focused on perovskites, particularly in the quest to create more efficient and sustainable solar cells. These materials absorb certain colors of the visible spectrum of sunlight effectively and can be layered with other materials, such as silicon, that catch additional wavelengths of light the perovskite does not absorb.

"This is a way to examine the material properties on a very elementary level, so that in the future we’ll be able to design materials with certain properties in a more directed way."

“(Perovskites) are easy to fabricate and have a very high solar cell efficiency, and can be applied as a very thin film,” explains Roland Wilcken, first author on the new paper and a post-doctoral researcher in Raschke’s research group. “But the problem with this material is it has relatively low photostability.”

Improving the material’s performance is no easy feat. There’s a large possible combination of chemical compositions and preparation conditions of perovskite solar cells, which affect their structure, performance and stability in ways that are difficult to predict. This is a challenge also faced by many other complex materials used for semiconductors, quantum materials, displays or in biomedical applications.

This is where the ultrafast microscope helps the researchers gain the spatial and temporal information needed to optimize the material—and in turn—find a good compromise between stability and performance.

Building the ultrafast microscope was a challenge, explained Branden Esses, a physics graduate student and research contributor. The team used nanotips, coated in a platinum alloy or gold, which are brought within nanometers of the perovskite layer, then hit with a sequence of laser pulses.

The first pulse excites the electrons in the visible, and subsequent pulses in the infrared watch how the electrons and molecules interact and move in time, Esses says, adding that “if you shine a light on this very tiny tip, the light that comes back is very weak since it only interacts with very few electrons or molecules; it’s so weak that you need special techniques to detect it.”

So, they developed a special method, modulating the light beams and using optical-amplification techniques to reduce noise and background to isolate the desired information.

Both how “the light is focused at the nanometer scale with the tips and how it is emitted and detected was essential to get enough contrast and signal to make these ultrafast movies of the material,” Wilcken explains.

And thanks to the ultrafast microscope technology, researchers are able to capture ultra-high-resolution images of femtosecond movement, measuring atomic motion in the molecules with very high precision. A particular feature of this development is the ability to resolve the dynamics of the molecular vibrations as a spectator of how the material responds to the photoexcited electrons.

Building better and functional materials from the bottom up

“This is a way to examine the material properties on a very elementary level, so that in the future we’ll be able to design materials with certain properties in a more directed way,” explains Sean Shaheen, a professor of electrical, computer and energy engineering who provided the material sample and collaborated on the research.

“We’re able to say, ‘We know we prefer this kind of structure, which results in, for example, longer lived electronic excitations as linked to photovoltaic performance,’ and then we’re able to inform our material synthesis partners to help make them,” Esses adds.

One of the surprising results of the work is that “in contrast to conventional semiconductors it seems that more structural disorder gives rise to more stable photogenerated electrons in hybrid perovskites,” Raschke explains. With the ultrafast microscope it became possible for the first time “to directly image the role of molecular order, disorder and local crystallinity on the optical and electronic properties of materials in general.”

This discovery is expected to have a profound impact on material science for advancing the performance of novel semiconductor and quantum materials for computing, energy and medical applications.

The instrument development was supported by the National Science Foundation, through STROBE, an NSF Science and Technology Center for which Raschke serves as co-principal investigator.

Roland Wilcken, Branden Esses, Rachith Nithyananda Kumar, Luaren Hurley, Sean Shaheen and Markus Raschke contributed to this research.

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New ��Ҵ�ý�ƽ�� research harnesses the power of an ultrafast microscope to study molecular movement in space and time.

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Learning about the beginning of the universe in trillions of degrees

Rachel Sauer — Fri, 24 Jan 2025 00:09:52 +0000

Learning about the beginning of the universe in trillions of degrees Rachel Sauer Thu, 01/23/2025 - 17:09

��Ҵ�ý�ƽ�� Professor Jamie Nagle will discuss the quarks and gluons that formed at the Big Bang in his Distinguished Research Lecture Feb. 6

Ten trillion degrees Fahrenheit is unfathomably hot—more than 10,000 times hotter than the Sun’s core—and it’s the temperature of the universe just moments after the Big Bang. At such extreme temperatures, according to nuclear theory, ordinary matter made of protons and neutrons transforms into a plasma of fundamental particles called quarks and gluons.

Jamie Nagle, a ��Ҵ�ý�ƽ�� professor of physics, will discuss his research to unlock the secrets of the early universe in his Distinguished Research Lecture Feb. 6.

At the world’s most powerful accelerators, scientists recreate tiny droplets of this early-universe matter by colliding heavy nuclei at near-light speeds. One of these scientists is Jamie Nagle, a University of Colorado Boulder professor of physics who for 20 years has studied these fleeting droplets and, along with his research group, engineered their shapes, sizes and temperatures to better understand their properties.

Nagle will discuss this work in the 125th Distinguished Research Lecture, “10 Trillion Degrees: Unlocking the Secrets of the Early Universe,” at 4 p.m. Feb. 6. in the Chancellor's Hall and Auditorium of the Center for Academic Success and Engagement (CASE).

��Ҵ�ý�ƽ�� Jamie Nagle

Nagle has spent much of his career investigating the early universe through high-energy nuclear physics. His research has focused on understanding the quark-gluon plasma, a state of matter theorized to have existed just microseconds after the Big Bang.

“As you go back to about six microseconds after the universe started, the temperature was around two trillion Kelvin,” Nagle explains. “It was theorized that protons and neutrons inside of nuclei would melt away, creating a bath of more fundamental particles—quarks and gluons.”

Nagle's work involves recreating droplets of this quark-gluon plasma in a laboratory by colliding large nuclei at nearly the speed of light. These collisions occur at the world’s highest-energy accelerators, including the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory in New York and the Large Hadron Collider (LHC) in Geneva, Switzerland.

“In the world's highest-energy accelerators, we can collide very large nuclei like gold, lead or platinum at such high velocities that we create a tiny droplet of this 2 trillion Kelvin plasma,” he says.

If you go

What: 125th Distinguished Research Lecture, 10 Trillion Degrees: Unlocking the Secrets of the Early Universe

Who: Professor Jamie Nagle of the Department of Physics

When: 4-5 p.m. Feb. 6, followed by a Q&A and reception

Where: Chancellor's Hall and Auditorium, Center for Academic Success and Engagement (CASE)

Reflecting on the award, Nagle expresses gratitude and a sense of accomplishment: “It means a lot to me. You get to a certain middle age and are more self-confident, but this recognition feels rewarding. There's a lot of effort, and much of the hard work goes unnoticed. It’s nice to feel like the fruits of that labor are appreciated.”

The Distinguished Research Lectureship also emphasizes communicating complex scientific concepts to broader audiences. For Nagle, this is a vital part of his work: “This award is very meaningful to me because I often listen to the lectures of past recipients. It's about communicating the broader context of why this scientific research is important, not just within the microcosm of nuclear physics.”

��Ҵ�ý�ƽ�� the Distinguished Research Lectureship

The Distinguished Research Lectureship is among the highest honors given by faculty to a faculty colleague at CU Boulder. Each year, the Research and Innovation Office requests nominations from faculty for this award, and a faculty review panel recommends one or more faculty members as recipients.

The lectureship honors tenured faculty members, research professors (associate or full) or adjoint professors who have been with ��Ҵ�ý�ƽ�� for at least five years and are widely recognized for a distinguished body of academic or creative achievement and prominence, as well as contributions to the educational and service missions of CU Boulder. Each recipient typically gives a lecture in the fall or spring following selection and receives a $2,000 honorarium.

Read the original article from the Department of Physics

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��Ҵ�ý�ƽ�� Professor Jamie Nagle will discuss the quarks and gluons that formed at the Big Bang in his Distinguished Research Lecture Feb. 6.

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CU president urges Quantum Scholars to think critically and creatively

Rachel Sauer — Tue, 10 Dec 2024 23:20:49 +0000

CU president urges Quantum Scholars to think critically and creatively Rachel Sauer Tue, 12/10/2024 - 16:20

Rachel Sauer

At the program’s December meeting, Todd Saliman reaffirmed CU’s commitment to the quantum education and research happening on campus

The way University of Colorado President Todd Saliman sees it, “(quantum) is a sector where Colorado is uniquely well-situated... I want us to be the one. I want us to be front of the line. I want us to be leading the world.”

As for the Quantum Scholars he was addressing Wednesday evening, their mission is to think “critically and creatively, and be dynamic human beings,” Saliman said.

Professor Noah Finkelstein co-directs Quantum Scholars with Michael Ritzwoller. (Photo: Casey A. Cass/��Ҵ�ý�ƽ��)

Saliman was a guest speaker at the December meeting of Quantum Scholars, a program conceived in the University of Colorado Boulder Department of Physics and the College of Engineering and Applied Science (CEAS) that offers undergraduate students opportunities to learn about the quantum field, including connections with local industry leaders and introduction to new quantum technology.

The Quantum Scholars program includes undergraduates studying physics, engineering and computer science and aims to advance quantum education and workforce development through professional development, co-curricular activities and industrial engagement.

“We’re trying to extend what the Quantum Scholars are learning in class to make their education even more marketable and relevant,” said Michael Ritzwoller, a physics professor of distinction and Quantum Scholars founder with CEAS Dean Keith Molenaar. “More than 80% of our graduates eventually work in industry, so Quantum Scholars helps fill that gap.”

Scott Davis (PhDPhys’99), CEO of Vescent Technologies Inc. and a member of the Department of Physics advisory committee, told students at the Wednesday meeting that they are “at a special place” and cited the National Quantum Initiative Reauthorization Act (S. 5411), introduced in the U.S. Senate last week, which would authorize $2.7 billion over the next five years for quantum research and development at federal agencies and shift focus “from basic research to practical applications.”

“So much of that started because of this institution,” Davis said. “We’re really just at the beginning, and we need CU to keep doing what you’re doing—technical development, workforce development, inventing the future.”

Supporting scholars

For Denali Jah, a senior majoring in engineering physics who has been a Quantum Scholar since the program began in spring 2023, the benefits of participating in it are many. The $2,500 that Quantum Scholars receive during the academic year—supported by the Department of Physics and CEAS, as well as contributions from alumni, industry and external partners—gave his budget some wiggle room so he could participate more fully in research and community initiatives.

CU President Todd Saliman (left) spoke to Quantum Scholars at the program's monthly meeting. (Photo: Casey A. Cass/��Ҵ�ý�ƽ��)

“I was looking for some way to contribute to the physics department and really put my stamp on CU before I left,” Jah says. “Professor Ritzwoller and I were talking and he said, ‘I really want a quantum hackathon to happen here at CU,’ so Annalise Cabra and I organized the quantum hackathon.

“It was a really great success on the whole, and a great opportunity for Quantum Scholars to be able to get some industry initiatives that were much better integrated into our program. One way that I see Quantum Scholars is we’re a curation of student opportunities. Everybody is really working to be able to create more and more initiatives and opportunities throughout campus.”

Luke Coffman, a senior studying physics and mathematics, is leveraging his time as a Quantum Scholar to study “useful ideas for quantum computation,” he noted during the Wednesday meeting. Specifically, he’s interested in molecular simulation for qubit systems and suggested that perhaps quantum sensing will happen before quantum computation.

“Theoretical quantum computing will always be hot,” added Noah Finkelstein, a professor of physics and Quantum Scholars co-director.

In response to a question from Alexander Aronov, a junior studying mechanical engineering, about whether quantum science is in a period of over-hype, Davis noted that the technology field broadly has long existed in a cycle of hype and bust: “Is that happening in quantum?” he asked. “I take a fairly broad view of what it means to be in quantum systems and a quantum player.

“Exploiting quantum to our benefit is not hype; it’s real… It’s been slowly building for a long time, especially the amount of money (dedicated to quantum research and development) on the public side because of national security aspects. We exploit the laws of physics to the advantage of humanity, and that’s not going anywhere.”

Saliman said that as an institution, CU is committed to quantum—to building and leveraging public and private partnerships that help fund the research and development of which Quantum Scholars are or will be a part. “Our job is to support smart people, and translating the discoveries made here into practical applications is going to help pay for it.”

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At the program’s December meeting, Todd Saliman reaffirmed CU’s commitment to the quantum education and research happening on campus.

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CU President Todd Saliman (second from left) talks with (left to right) professors Noah Finkelstein and Tobin Munsat, Scott Davis and Professor Michael Ritzwoller. (Photo: Casey A. Cass/��Ҵ�ý�ƽ��)

Physicist’s dissertation gets top marks from American Physical Society

Anonymous — Fri, 24 May 2024 15:05:33 +0000

Physicist’s dissertation gets top marks from American Physical Society Anonymous (not verified) Fri, 05/24/2024 - 09:05

Blair Seidlitz, now a postdoctoral researcher at Columbia University, studied near-collisions of nuclear beams at the Large Hadron Collider in Switzerland, and he did so despite having severely limited vision

Blair Seidlitz, who earned his PhD in physics in 2022 from the University of Colorado Boulder, has won the American Physical Society (APS) Dissertation Award in Hadronic Physics for his dissertation, the society announced.

Seidlitz’s dissertation research was on the ATLAS Experiment of the Large Hadron Collider, hosted at the international CERN laboratory in Switzerland. His ��Ҵ�ý�ƽ�� research group, led by Professors Dennis Perepelitsa and Jamie Nagle, works in experimental nuclear physics—it collides nuclear beams (“ions") at the LHC to study the fundamental forces of nature under extreme conditions.

The major advance of Seidlitz’s dissertation was to use these nuclear beams at the LHC in an unusual way. “He was interested in the processes not where the beams slam into each other … but instead the cases where the beams just barely miss each other,” Perepelitsa said.

��Ҵ�ý�ƽ�� physics PhD alum Blair Seidlitz won the American Physical Society (APS) Dissertation Award in Hadronic Physics for his dissertation research on the ATLAS Experiment of the Large Hadron Collider.

“It turns out that in these cases, a photon emitted by one ion can strike the other, and thus result in rare and unusual ‘photo-nuclear’ collisions …. The ATLAS detector was not set up to take this kind of data by default. So Blair had to do a lot of work to develop the ‘trigger’ (the algorithms that decide which data to even record), to get access to this rare dataset.”

Perepelitsa said this kind of work is unusual for a graduate student; many graduate students work with existing infrastructure or use well-established procedures in research like this. “But Blair really took his idea from the conception stage, to implementing it himself, and helping to deploy it in person during data-taking at CERN,” a bustling scientific community at which Seidlitz spent significant time.

Once Seidlitz had collected the data, he then did a very careful analysis, which necessitated developing some new methods because nobody had really done this kind of thing before, Perepelitsa added.

The surprising result was that these sparse “photo-nuclear” collisions exhibited a collective “flow” behavior among their produced particles—“something you might only expect in the collisions of large nuclei where there are many, many particles that are produced and interact.”

“His measurement has come at a time when the scientific community is asking big questions, such as: Just how few particles can one have to still exhibit many-body collective motion? Blair’s thesis work, by paving the way to experimentally access these unusual datasets, is addressing these open questions head on!”

Seidlitz is now a post-doctoral researcher at Columbia University. He still works at ATLAS, but he now also works at a new experiment at the Relativistic Heavy Ion Collider, in which Perepelitsa and Nagle’s group at CU is closely involved. “So we are pleased that we can continue to collaborate with Blair very closely,” Perepelitsa said.

Seidlitz said he hopes to build on his graduate school work. “There are actually distinct categories (or types) of photon-nucleus collisions. My thesis work did not sort the different types, but studied them as a whole. In principle, it should be possible to sort these, although it has never been done. That way, we could study the ‘flow’ properties of each type individually, which would be really interesting.”

Seidlitz said that he and his colleagues will be able to study these types of collisions at the Electron Ion Collider, which is scheduled to be completed in the 2030’s at Brookhaven National Laboratory (BNL) on Long Island, New York.

Seidlitz said he was surprised to win the APS dissertation award. “They called me while I was in the sPHENIX control room (an experiment at BNL). I don't usually pick up my phone, but it seemed to not be spam, and as fate would have it, it was an official from APS saying I had won.”

Seidlitz has charted a successful academic career even though he has Stargardt's disease, a rare form of macular degeneration that leaves him with approximately 1/20th the visual acuity of average people.

A wheel in the ATLAS detector of the Large Hadron Collider. Blair Seidlitz's dissertation research focused on near-collisions of nuclear beams in ATLAS. (Photo: CERN)

His vision posed many challenges, he said. “I guess the first challenge was learning as much as I could and getting through courses without being able to see the black board or projector, where I did most of my learning through textbooks.”

Seidlitz said disability service centers at ��Ҵ�ý�ƽ�� and at his undergraduate institution, the University of Wisconsin, Madison, “really made it possible for me to succeed, from scanning old textbooks to make PDFs, to scanning students' homework so I could grade it when I was a TA and recommending assistive technology.”

Another challenge was finding a field of research that would work for him. “Because physics that revolves around particle accelerators is so big and complicated, large collaborations are formed and the work is shared. Some people build the detectors—something I could not do—and others set up data analysis and reconstruction, which is a lot of software to take the signals from individual detectors and turn it into a measurement of a photon with a particular momentum, for example,” Seidlitz explained, adding:

“This is something I can do! I would say there are still challenges day to day, but they are manageable, and I am very grateful that I am in a place where I can contribute and do valuable work.

Seidlitz grew up in Wisconsin and earned a BS in engineering physics from the University of Wisconsin, Madison. As an undergraduate, he conducted research in plasma physics with Cary Forest, applying optical emission spectroscopy techniques for measurements of the electron temperature in the Plasma Couette Experiment and the Madison Plasma Dynamo Experiment.

The American Physical Society is a nonprofit organization working to advance and diffuse the knowledge of physics through its research journals, scientific meetings and education, outreach, advocacy and international activities.

APS represents more than 50,000 members, including physicists in academia, national laboratories and industry in the United States and throughout the world.

Top image: The eight toroid magnets surrounding the calorimeter in the ATLAS detector. The calorimeter measures the energies of particles produced when protons collide in the center of the detector. (Photo: CERN)

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A Nobel laureate walks into a first-year physics class…

Anonymous — Fri, 19 Apr 2024 18:57:11 +0000

A Nobel laureate walks into a first-year physics class… Anonymous (not verified) Fri, 04/19/2024 - 12:57

Rachel Sauer

General Physics for Majors course designed by ��Ҵ�ý�ƽ�� Professors Eric Cornell and Paul Beale shows students that the furthest reaches of science are built on fundamental concepts

The Nobel laureate was not feeling happy about his minus signs.

He stood back from the blackboard—yes, an actual blackboard on which he wrote with actual chalk—and considered the calculus he’d jokingly hyped just moments before with, “This is some of that real calculus sensation. This is why you sat through that whole calculus class: for this moment.”

His team teacher, a noted scientist who this year is marking 40 years teaching physics at the University of Colorado Boulder, called from the back of the classroom, “That’s right, Eric.”

Professors Paul Beale (left) and Eric Cornell prepare for a Tuesday morning PHYS 1125 class. (Photos: Rachel Sauer)

Advanced math is not always easy with an audience watching—in this case, about 85 first-year physics, astrophysics and engineering physics students in PHYS 1125, General Physics 2 for Majors.

It’s a class for students who know they want to pursue a field of physics and are newly starting out in it. And it’s taught by a Nobel laureate.

“I harken back to freshman physics every day of my life,” explains Eric Cornell, a ��Ҵ�ý�ƽ�� professor adjoint of physics and 2001 Nobel Prize winner in physics for his work with Bose-Einstein condensates. “I’m in a Facebook group with people I met my freshman year in physics.”

In other words, there’s absolutely no reason a Nobel laureate shouldn’t teach first-year physics.

Basic, foundational concepts

Cornell and Paul Beale, a ��Ҵ�ý�ƽ�� professor of physics, created the course six years ago, in part to help students interested in pursuing physics to find community and support among like-minded peers. While other introductory physics courses are open to all majors, this one is specifically for physics, astrophysics and engineering physics majors. Steven Pollock, a professor of physics, and Yuan Shi, an assistant professor of physics, in the fall taught the first half of the course, PHYS 1115, which was created by Professors Chuck Rogers and Shijie Zhong.

“We start from ground zero,” Beale says. “Most (of the students) have had some physics in high school, most have seen these ideas before—they know that same charges repel. But even students who have had really good high school physics classes, maybe even AP classes, we say, ‘That’s great! Take our class.’

“Being with other physics majors helps them relax and get immersed in the field. Everybody in there really wants to be in there.”

Professor Eric Cornell (center, striped shirt) answers student questions in the physics help room.

A cynic might ask, however, why a Nobel laureate would be teaching a first-year class. Shouldn’t they be, you know, spending their time in the furthest, most esoteric reaches of physics? Doing the kind of science only a handful of people on the planet can understand?

“I want to push back on that idea that the basic, foundational concepts of physics don’t have considerable charm of their own,” Cornell says. “This is really fun stuff, and one of the things I like about this course is it gets into really interesting things right away.”

“It’s also a hard class,” Beale adds. “The concepts are difficult, so the challenge for us is to do everything we can to make them approachable. (The students) have got to get them right even though they’re hard, because everything else in physics builds on what they learn here.”

Cornell and Beale designed the class not only with beginning physics students in mind, but learning assistants and graduate students as well.

“In a lot of schools, grad students—who might be just one year past undergrad—are thrown in the classroom and told, ‘Here, go teach,’” Cornell says. In this course, however, graduate students assist with weekly tutorials but meet with Beale and Colin West, an associate teaching professor of physics, before each one, because the skills of teaching need to be taught. The same is true for class learning assistants, who are undergraduate students who took the course the previous year.

Cornell and Beale also spend time in the physics help room each week, which is a space where students can drop by for help with anything physics related.

“I would say that we are a very good teaching department, and not just our graduate program,” Beale says. “This is your introduction to physics, and you’re either going to like it or not, so we put a lot of effort into the first years.”

“We’re always asking, ‘How do we do better teaching?’” Cornell adds. “People like Paul and me have the advantage of people in this department who have studied teaching and have tried approaches like using clickers, using a conversational approach, using hands-on demonstrations. There are ongoing discussions about how we can be teaching better.”

Physics with a purple crayon

Sometimes, better teaching means an apology: “It’s my sorry duty to apologize for all the sins of physicists who went before me, and electrical engineers. And Ben Franklin,” Cornell said, writing “sorry!!” on the blackboard and underlining it twice. “I’m here to apologize for this thing called ‘potential.’ The whole rest of your life you’re going to be thinking about electric potential. It’s unavoidable. Your intuition will overwhelm your minus-sign errors.

Professor Paul Beale (standing, blue sweater) walks around the classroom during PHYS 1125 to help students and answer questions.

“It’s a ‘sorry, but...’ though, which is another way to say, ‘Suck it up.’”

While Cornell pivoted to voltage, “a happier, friendlier term (than electric potential),” Beale walked slowly among the rows of seats, stopping to sit by students who had questions and prompt them toward their response on class-wide clicker questions.

Pranay Raj Poosa, a freshman majoring in astrophysics who hopes to study black holes and neutron stars, cites Cornell’s and Beale’s enthusiasm for physics and their personal, conversational approach to teaching as two of the reasons he likes the class: “The fun they generate makes my understanding crystal clear,” he said. “The first day of class, (Cornell) made a joke about himself, which I personally felt was clap-worthy.”

Poosa added that he was in “utter disbelief” when his advisor mentioned a Nobel laureate would be teaching the class.

For Min Wang, a sophomore majoring in physics and interested in theoretical neuroscience and writing science fiction, Cornell and Beale have shown her that “great minds are not the ones who are walking in front of others all the time. They always slow down and let the young generation be on their shoulders.

“Even though what Professor Cornell taught us is just a tiny piece of knowledge in his mind, he shows amazing patience to every student and shows us how profound even a little, tiny bit in physics can be. And since I have time conflicts with all the office hours, Professor Beale gives me a special office hour time according to my school schedule. It is after class and work time on Friday! They make me feel welcome in the world of physics.”

Wang noted that while learning physics is not without its pains, she doesn’t feel alone in tackling them because she is part of a “lovely and supportive physics community created by the professors.”

Which is good, because it was time to do “a very modest amount of algebra, the kind you could do with a purple crayon if you’ve got one,” Cornell said, explaining how they could figure capacitance between two metal plates and then telling the students, “I’m going to show you something which I think is very neat. It’s kind of an advanced idea, giving you a taste of physics to come.”

The key thing to remember? “The whole idea of physics is zooming all the way into what does matter and ignoring what doesn’t.”

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General Physics for Majors course designed by ��Ҵ�ý�ƽ�� Professors Eric Cornell and Paul Beale shows students that the furthest reaches of science are built on fundamental concepts.

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Nobel Prize winner Andrea Ghez to give 53rd Gamow lecture

Anonymous — Wed, 21 Feb 2024 17:10:38 +0000

Nobel Prize winner Andrea Ghez to give 53rd Gamow lecture Anonymous (not verified) Wed, 02/21/2024 - 10:10

Astrophysicist who confirmed black hole at galaxy’s center to speak March 5 at ��Ҵ�ý�ƽ��

Andrea Ghez, recipient of the 2020 Nobel Prize in physics, will give the 53rd George Gamow Memorial Lecture March 5 at the University of Colorado Boulder.

Ghez, Lauren B. Leichtman and Arthur E. Levine Professor of Physics and Astronomy at UCLA, shared half of the prize with Reinhard Genzel of the University of California, Berkeley.

Andrea Ghez, 2020 Nobel Prize winner in physics, will give the 53rd George Gamow Memorial Lecture March 5 at the University of Colorado Boulder. (Photo: The Nobel Foundation)

The pair were recognized by the Nobel committee for their discovery of a “supermassive” black hole at the center of the Milky Way galaxy. Ghez, head of UCLA’s Galactic Center Group, solved the question, what exactly is “Sagittarius A*,” which was first detected as a mysterious radio signal in 1933.

“I see being a scientist as really fundamentally being a puzzle-solver,” Ghez said in 2021. “Putting together the pieces, trying to find the evidence, trying to see the bigger picture.”

If you go

What: 53rd George Gamow Memorial Lecture

Who: Andrea Ghez, recipient of the 2020 Nobel Prize in Physics

When: 7:30 p.m. Tuesday, March 5

Where: Macky Auditorium, University of Colorado Boulder campus

Tickets: Free and open to the public

Learn more

She helped develop a new technology to correct the distorting effects of Earth’s atmosphere. Gathering data from the world’s largest telescope system, the W. M. Keck Observatory in Hawaii, she and her team continue to plumb the depths of the galactic center 26,000 light years distant.

While Albert Einstein’s epochal work on relativity remains the best description of how gravity works, Ghez says it can’t account for gravity inside a black hole. Through what she calls “extreme astrophysics,” she seeks to go where the pioneering astrophysicist could not.

“Einstein’s right for now,” she said. “However, his theory is showing vulnerability. … At some point we will need to move … to a more comprehensive theory of gravity.”

A member of the National Academy of Sciences and author of a 2006 children’s book, “You Can Be a Woman Astronomer,” Ghez is widely recognized as a role model for young women.

“Seeing people who look like you, or are different from you, succeeding shows you that there’s an opportunity,” she said.

Top image: An artist's concept illustrating a supermassive black hole with millions to billions times the mass of the Sun. (Illustration: NASA/JPL-Caltech)

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Astrophysicist who confirmed black hole at galaxy’s center to speak March 5 at ��Ҵ�ý�ƽ��.

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