Author: Richard Jones

UConn Astronomers React to First Photo of a Black Hole

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credit: Event Horizon Telescope collaboration

This image is the first ever taken of a black hole, captured by the Event Horizon Telescope (EHT) project. The black center is a direct view of the event horizon of a supermassive black hole with a mass of 6.5 billion times the Sun, lying at the center of the Virgo cluster of galaxies. The bright ring is emission from hot gas just above the event horizon, with an asymmetric shape caused by gravitational lensing of light in the strong gravity of the black hole. The EHT collaboration captured the image using a network of 8 radio telescopes that spanned the Earth, effectively creating a planet-sized interferometer.

For more information, see the full NSF press release:

This result directly impacts research in galaxy evolution and cosmology that is being carried out at UConn. The following comments from UConn Astrophysics researchers indicate the level of interest that this result has generated within the international Astrophysics community.

This is a stunning technical achievement. Supermassive black holes are the most extreme objects in the Universe, bizarre rips in spacetime that lie in the center of every massive galaxy. But despite their extreme properties, black holes have a remarkably simple mathematical description, with just a few numbers describing all of their vital properties: mass, size, and spin. Until now, the only way to measure black holes was through indirect methods, like my own research program that uses the timing of light echoes in the surrounding gas. The Event Horizon Telescope black hole image is a tremendous first step in a new understanding of extreme gravity and the detailed astrophysics of black holes. – Jonathan Trump, Assistant Professor
I am fascinated by this result and how we can actually see a direct image of a black hole that is a trillion times our distance to the Sun. This is truly an amazing result for human beings achieved within the limitation of our observational instruments. As an observational astronomer who works with black holes, this result also opens up new possibilities to learn about their unknown features such as black hole spin that could revolutionize our understanding of black hole physics. – Yasaman Homayouni, Graduate Student
This result is a beautiful demonstration of what is possible when the global community works in concert towards a scientific goal. Sometimes the greatest discoveries are not found by the biggest new telescopes in space, but through creative thinking, years of dedicated effort, and big data techniques, building upon what we have here on Earth. – Cara Battersby, Assistant Professor
It is truly extraordinary to be able to provide this new evidence for Einstein’s ideas on space and time through observations made no less than one hundred years since he first proposed them. As to the discovery itself, there are two aspects to black holes, one is that they pull everything in, and the other is that they do not let anything out. With nothing being able to get out, they thus look black to an observer on the outside, to thereby give them their black hole name. Now for many years we have had evidence of things falling into black holes, but had never previously had any evidence that things cannot get out. These new data show a fireball ring of things falling in, with the ring surrounding a black space in the center where nothing can get out. We thus confirm that indeed nothing can escape a black hole. – Philip Mannheim, Professor

For more about this topic, see this recent article in the Daily Campus, UConn Astronomy Community Responds Joyously to M87 Black Hole Image.

Hands-On Approach to Physics

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Step into a fall 2018 class section of PHYS 1602: Fundamentals of Physics II, and you’ll find a scene that’s far from the large introductory science lectures common on most college campuses.

Anna Regan ’21 (CLAS) utilizes a whiteboard to try out
solutions during her group’s problem-solving tutorial.
(Bri Diaz/UConn Photo)

To start, the class of 30 students sits at several triangular workspaces, which today are covered with wires, coils, magnets, and power supplies that the students are using to demonstrate electromagnetic induction. At the start of class, the instructors provided a short lecture before the students set off on their own problem-solving tutorials.

Now, the instructors move from group to group, stopping to answer questions, as students shuttle back and forth to the whiteboards that line the classroom walls.

It’s a scene that’s about to become common in UConn physics courses, thanks to renovations to the Edward V. Gant Science Complex, according to Barrett Wells, professor and head of the Department of Physics.

“We’re rebuilding our classes from the ground up,” he says. “It’s the basis for what we’re going to spread across most of our introductory courses.”

The curricular redesign, says Wells, will replace the typical large-lecture format with smaller classes, utilizing five new studio-style physics learning laboratories to be added to the Gant Science Complex in 2019. These changes will promote active learning, collaborative problem solving, and faculty-student interaction, he says.

“This is a trend we’re seeing in our discipline,” Wells says. “Restricting class size to promote students actively participating during class has been documented to help them achieve and learn more across the board.”

Lecture Meets Lab

Traditional science courses, including those in physics, typically consist of three weekly lectures that hold 100 to 200 students, with once-per-week lab sections where students practice the concepts they learn in lecture.

But this setup poses challenges for professors and teaching assistants to cover the material at the same rate, often causing lecture and lab sections to fall out of synchrony, says Diego Valente, assistant professor in residence of physics and instructor of Fundamentals of Physics II.

In addition, many physics concepts are difficult to teach within the logistical setup of a lecture, and the instructors may have a difficult time knowing whether students comprehend the material, says Valente.

To combat these issues, the Department of Physics piloted redesigned versions of Fundamentals of Physics I and II, the introductory sequence for physics majors, in the spring and fall of 2018, respectively.

Course instructor and Ph.D. student Lukasz Kuna ’14
(CLAS), ’17 MS assists a group that includes Ian Segal-
Gould ’21 (CLAS), far right. (Bri Diaz/UConn Photo)

The new courses, which will use the physics learning laboratories, merge the lecture and lab sections into three 2-hour class periods per week that hold up to 54 students. Classes are led by the same professor and graduate students.

“[The studio classrooms] allow instructors to interact with students more frequently and discuss concepts with them in depth,” says Valente. “Previously, hands-on group work was limited to lab courses. Now, every single day in class there’s some kind of group activity where students solve problems.”

Lukasz Kuna ’14 (CLAS), ’17 MS, a physics Ph.D. student and teaching assistant for Fundamentals of Physics II, agrees.

“We can present a topic that’s somewhat difficult to understand, and then attack it from all angles,” he says. “It certainly should be the way physics is taught, because it prepares you for more difficult problem solving.”

A Learning Community

The studio learning model also increases the amount of time students spend working collaboratively, says Valente.

Ian Segal-Gould ’21 (CLAS), a physics and mathematics major enrolled in Fundamentals of Physics II, says that the class fosters the collaborative problem-solving that is expected of professional physicists.

“In lecture-based courses, people look at the professor,” he says. “They’re not talking to each other, they’re not solving the problem—they’re looking at somebody else solve the problem. In the real world, physicists work together, so I think the interactive component to this course is on the right track.”

Physics major Megan Sturm ’21 (CLAS) says that working in small groups helps build camaraderie and exposes her to new ideas.

“I know at least half of the class, and it’s way easier to learn that way,” she says. “Someone else will ask a question or say something during the lab that I wouldn’t have even thought about.”

Sturm also says that she enjoys the frequency of interaction with the instructors, noting that Valente circulates through the class, asks students specific questions, and engages in hands-on work with them.

Physics major Megan Sturm ’21 (CLAS) says that working
in small groups helps build camaraderie and exposes her to
new ideas. (Bri Diaz/UConn Photo)

“He’s way more approachable, so when I’m having trouble with things, I don’t have a problem going to office hours,” she says.

Kuna, who has taught for three years in the Department, says that the faculty-student interaction helps him better gauge how students are learning the material.

“Traditionally, if you’re teaching in a large lecture, you somewhat lose the students when they go to lab,” he says. “Here, you get to see where your class stands.”

New Opportunities

With a target completion date for phase one renovations set for fall of 2019, the Department is gearing up to redesign other introductory courses, including Physics for Engineers and Physics with Calculus, a general education sequence taken by many pre-med students.

“This is important because we offer courses to majors across the University, and we’re teaching more students each year,” Wells says.

“Our goal is to develop not just comprehension of physical concepts, but also transferable skills–things like communication through group work and computer programming, which students can use in their professional lives,” adds Valente.

He says that these investments in teaching and infrastructure give UConn an advantage in addressing instructional issues common at institutions across the United States.

“This is a really large-scale venture we are doing, something a lot of comparable institutions aren’t able to do,” Valente says. “It shows that UConn is making a big commitment to physics education.”

By: Bri Diaz, College of Liberal Arts and Sciences
This article was originally published in the UConn CLAS Newswletter, November 28 issue

Workshop ‘Dynamic Quantum Matter’ organized by UConn faculty

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Dynamic Quantum Matter, Entangled orders and Quantum Criticality Workshop
Dates: June 18- June 19, 2018

Sponsors

UConn, NSF, Nordita, Villum Center for Dirac Materials, Institute for Materials Science – Los Alamos, Wiley Publishers
           

Scope

The conference will focus on entangled and non-equilibrium orders in quantum materials. The 21st century marked the revolution of probing matter at the nano- to mesoscale and these developments continue to be the focus of active research. We now witness equally powerful developments occurring in our understanding, ability to probe, and manipulate quantum matter, in entangled orders and novel states, in the time domain. Recent progress in experimental techniques including x-ray optics, optical pumping, time resolved spectroscopies (ARPES optics), and in cold-atom systems has led to a resurgence of interest in the non-equilibrium aspect of quantum dynamics. The novel entangled orders that have nonzero “overlap” with more than one order parameter also have emerged as an exciting new direction for research in quantum matter. Entangled orders go beyond the conventional orders such as density and spin, and significantly expand the possible condensates we can observe. It is only because of the lack of experimental control, resolution, theoretical framework, and computational power, that the realm of entangled and quantum non-equilibrium remained largely unexplored until now. The time has come for us to turn full attention to these phenomena. Specific topics include: superconductivity and dynamics near quantum criticality, composite orders in correlated materials, effects of strain on quantum critical points, and superconductivity in STO. This conference will have a format of topical lectures, while leaving ample time for discussions.

Venue

Gurney’s Resorts | Newport, RI

Department, alumni celebrate career of Prof. Doug Hamilton

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Friday afternoon on April 20, 2018 the UConn Physics Department held a colloquium in honor of Professor Douglas Hamilton on the occasion of his retirement from active service on the faculty. The colloquium was MC’ed by Prof. Jason Hancock, who surveyed the highlights of a career spanning four decades marked by notable accomplishments in research, teaching, and service. Several of Doug’s former students also presented tributes to their mentor, some in person, and some by video or written message, expressing their gratitude for what they learned from him, both by instruction and example. At the end of the hour, Doug presented some final comments, which were followed by a standing ovation in recognition of Doug’s many contributions to our field, our department, and the University. Doug, you will be missed!

-Richard Jones

Hands-on teaching of introductory physics gains momentum

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Students in PHYS 1601Q, taught by Professor Jason Hancock, work during a lab that observes how an external mass can affect oscillation by producing torque. They use a device called an ioLab to record data, and use the data in a program called Mathematica for analysis. The lab was in the Edward V. Gant science complex on April 20, 2018. (Garrett Spahn/UConn Photo)

 

A recently renovated physics classroom in the Edward V. Gant Science Complex was built to pilot a new approach to physics education, integrating lecture with lab rather than the classical approach of separating these components.

Students and instructors apply concepts with hands-on activities throughout the lecture, practice new tools, and problem solve as a group. The space is equipped with whiteboards on every wall, and computers and projectors for each station. Though built for entry-level courses such as Physics 1601 and 1602, the end goal is to convert larger classes into this format as well, including entry-level engineering and biology classes, for a more interactive learning experience.

This article first appeared in UConn Today on April 25, 2018

– Garrett Spahn ’18 (CLAS) & Elaina Hancock

In memoriam, George H. Rawitscher (1928-2018)

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It is with great sorrow that we report the passing of our long-time colleague and friend, George Rawitscher on March 10, 2018, after a brief illness and just having passed his 90th birthday, which was celebrated with a cake at a meeting of the UConn Physics Department. George was born in 1928 in Germany, where his fa-ther was a distinguished Professor of Botany at The University of Freiburg. In 1934 his father, Felix Rawitscher who was Jewish, brought his family which in-cluded George’s mother, Charlotte Oberlander, his sister Erika, and George from Germany to Brazil to escape the Nazis. In Brazil, Felix established and chaired the Botany Department, which still bears his name, at the University of Sao Paulo.

George grew up in Sao Paulo, where he learned fluent Portuguese. From an early age he knew he wanted to be a physicist, and taught himself quantum mechanics from a book during high school. He graduated in physics and mathematics from the University of Sao Paulo in 1949, and he served as an Instructor at the Brazilian Center for Physical Research in Rio de Janiero for two years, receiving a Brazilian National Research Council Fellowship. While he was in the Center for Physical Research at Rio, he worked under Richard Feynman who was a visiting professor at the same institute. He told his grandson Nicholas that Feynman had made a big mark on his life, inspiring his approach to physics, and observing that he had the potential to become a “real” physicist, which he remained until the end of his life.

Following his time in Rio, George went to Stanford University as a graduate student in theoretical nuclear physics and mathematics. He received his Ph.D. in 1956, for a study of Fierz-Pauli spin 3/2 particles and the anomalous magnetic moment of the muon under Profs. Leonard Schiff and D.R. Yennie. His first paper had to do with the effect of the finite size of the nucleus on muon pair production by gamma rays.

While at Stanford, George met and later married Mary Adams, a fellow Stanford student, and they proudly raised two sons, Peter and Henry. Mary, a biochemist, died in 1980. In his later years, George was again happily married to Joyce Rawitscher in 2009, who passed away in 2016. Following his graduate work, George became an Instructor at the Physics Nuclear Structure Center (University of Rochester) for two years and then joined the Physics Department at Yale as Instructor, doing research in collaboration with Prof. Gregory Breit. He remained at Yale as Assistant Prof. of Physics until 1964. He joined the Physics Department at the University of Connecticut in Storrs as an Associate Professor and then became Professor of Physics from 1972. He retired in 2009 but remained at UConn as an emeritus Research Professor until days before his death, continuing to do active research in nuclear physics, computational physics and ultracold atomic collision physics until his final days.

Prof. Rawitscher received several prestigious academic honors including one of the early Research Fellowship awards from the Alexander von Humboldt Foundation (Germany) in 1964 and became a Fellow of the American Physical Society, nomi-nated by the Division of Nuclear Physics in 2016. During his tenure at the University of Connecticut, he took academic leaves at the Max Planck Institut fur Kernphysik in Heidelberg (1964-1966), the Laboratory for Nuclear Science at MIT (1972), as guest professor at the University of Surrey, England 1973, the University of Maryland (1987-1988) and served on the Board of Directors of Bates Users Theory Group at MIT (1982-1985) and the Executive Committee of the American Physical Society topical group on Few Body Systems and Multi-Particle Dynamics (1993-1995). He gave a number of invited presentations in nuclear theory at conferences, published approximately 88 refereed papers and numerous conference proceedings. His principal research interests involved scattering problems using non-local opti-cal models of nuclear processes, coupled-channel reaction mechanisms for nuclear break-up such as the (e,e’p) reaction, and virtual nuclear excitations. Recently he emphasized development of numerical methods such as Galerkin and spectral expansions for solving integral equations. He has applied some of these techniques to studies of ultracold atomic collisions as well as nuclear reactions. His most recent refereed papers (2015-2017) concerned “Revival of the Phase-Amplitude description of a Quantum-Mechanical wave function.”

Professor Rawitscher was an engaged and untiring participant both in his Department and in the general community up to the last moments of his life. He promoted public awareness and activism on ameliorating the effects of global climate change and he and his wife Joyce have been active in the peace movement. He was a member of the Storrs, CT Quaker Meeting. He was also active in community service in the Storrs area, for example serving on the Town of Mansfield Sustainability Committee. Recently he has been working on a nearly-finished book summarizing his lifelong expertise in numerical computational physics, under contract with Springer, with two younger colleagues from Brazil. George was a dedicated and effective undergraduate teacher and empathetic mentor to a large number of graduate students, colleagues and collaborators. George was a central member of the department for more than 50 years, and has earned a special place in our hearts forever. His inspiring presence and example will be very much missed at the University, amongst his family, friends and the community, and it was a great loss to see him go.

UConn Prof. Kate Whitaker interviewed by Gizmodo

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Gizmodo has recently launched a new series of articles to explore how the best images in science were created and why.  In a recent article in this series by Ryan F. Mandelbaum entitled, “The Making of ‘Pillars of Creation,’ One of the Most Amazing Images of Our Universe”, the author presents a classic set of images taken with the Hubble Space Telescope showing a zoomed-in view of the Eagle Nebula. The article explains some of the details about the instrument that took these images, and how a color image is obtained by combining black-and-white photographs taken at a number of different wavelengths. In the article, UConn astronomer Prof. Kate Whitaker explains why an advanced space-based instrument like the HST is required to obtain awesome views like this of our cosmic neighborhood.

21st Annual Katzenstein Distinguished Lecture

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Monday, March 26, 2018

The 21st Annual Katzenstein Distinguished Lecture was hosted by the UConn Physics Department, featuring Dr. Takaaki Kajita, 2015 Nobel Prize Winner from the University of Tokyo, speaking on “Oscillating Neutrinos.”  After the lecture,  a banquet with the speaker was held for members and guests of the department. We enjoyed welcoming alumni and visitors to the department for this special occasion, made possible by a generous gift from UConn Physics alumnus Henry Katzenstein and his family.

Video recording of the lecture

Katzenstein lecture 2018

Physics students boost interdisciplinary research in materials

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Krishna (left) and Lukasz (right) posing in front of their EAM-2018 award winning posters.

By Amanda Olavarria

The Electronic and Advanced Materials Conference (EAM) is geared towards engineers, technologists, researchers and students with an interest in science, engineering and the applications of electroceramic materials. Several MSE students and faculty attended this year’s EAM Conference held in Orlando, FL.

MSE Associate Professor and Director for Undergraduate Studies, Serge Nakhmanson, co-organized a symposium at this event entitled “Mesoscale Phenomena in Ceramic Materials.” Four UConn students including Tulsi Patel, Krishna Chaitanya Pitike, Lukasz Kuna and Hope Whitlock showcased their research.

In addition to the oral presentations, two UConn students claimed 2nd and 3rd place in the American Ceramics Society (ACerS) Electronics Division “Best Student Poster Presentation” awards. Lukasz Kuna received 3rd place for his poster entitled, “Mesoscale Simulations of the Influence of Elastic Strains on the Optical Properties of Semiconducting Core-Shell Nanowires.” Krishna Chaitayna Pitike won 2nd place for his poster, “Shape and Size Dependent Phase Transformations and Field-induced Behavior in Ferroelectric Nanoparticles.”

In response to the latter award Serge Nakhmanson said, “This remarkable work involves contributions from five UConn students (including Physics undergraduate Hope Whitelock) and an exchange student from China visiting my group. It started as a team project in the “Phase Transformations in Solids” graduate class (MSE 5305). Since the original results appeared to be significant, we decided to continue this project beyond the end of the semester to generate a publication for a peer-review scientific journal. This is now being finalized for submission. It is relatively rare to see classroom projects successfully transition into publication quality research, but this one is being well received by the community.” Department Head Bryan Huey adds, “Devising a class project that can be guided through to a publication is a testament to Professor Nakhmanson’s commitment to teaching and the hard work he inspires with these bright students.”

EAM, jointly arranged by the Electronics Division and Basic Science Division of the ACerS, focuses on the properties and processing of ceramic and electroceramic materials and their applications in electronic, electro/mechanical, dielectric, magnetic, and optical components and devices and systems.

Categories: awards, conferences, news, research, students

Published: February 16, 2018