As part of the University of Maryland’s Education Abroad program, eligible students are welcome to apply for the the Physics in Florence semester, held at the International Studies Institute (ISI). Prof. Luis Orozco has been responsible for the program, which enrolled 12 students in the Fall of 2019. The curriculum includes three physics classes, an Italian language course, and an elective such as studio art, art history, history and political science, Italian language and literature, international business, and interdisciplinary studies in the humanities.  

One of this fall’s highlights was a visit to the Biblioteca Nazionale, located near the ISI.  Orozco and the students were able to see several of Galileo's original documents, including his log of experiments with inclined planes, his drawings of Jupiter's moons, and his watercolor of the moon's phases.

Another trip was to Geneva, where the students visited CERN. At the Compact Muon Solenoid (CMS) experiment, UMD postdoc Markus Seidel gave the students a tour of the detector, and graduate student Nathan Evetts of the University of British Columbia explained the workings of the Antiproton Ring. 

David Reitze, director of the U.S. gravitational observatory (LIGO), helped arrange a visit to the European Gravitational Observatory (EGO) near Pisa. Valerio Boschi hosted the students and explained the Virgo instrument and its interaction with the two LIGO interferometers in Louisiana and Washington state. After Boschi provided an extensive tour, EGO director Stavros Katsanevas met the students and discussed the current and future physics goals of EGO. 

Near the end of the term, students visited the Galileo Museum, in the Palazzo Castellani near their ISI classes.  The museum houses intriguing scientific instruments, including those of the Medici and the Grand Dukes of Tuscany. Examples include sextants, astrolabes, solar clocks, globes of various orientations, thermometers, telescopes, vacuum pumps and a Ptolemaic mechanical model showing the universe rotating around the earth.  Maps from the 16th century show remarkable accuracy, particularly for the east coast of North America and both sides of South America. Explorers Amerigo Vespucci and Giovanni da Verrazano were both natives of Florence.

At the center of the museum, the Galileo room highlights his contributions to mechanics with a reproduction of one of the inclined plane machines that he used to measure the relationship between time and distance under acceleration. There are also good references to his astronomical observations, with one of the original lenses of his telescope in place.

On a painted table of chemical affinities, the class spotted a symbol that looks like an h bar (ℏ, or Planck’s constant). Having learned about Planck’s constant in class, the students wondered about the symbol’s origin. Orozco found that it was originally a sickle, and that it had stood for lead in alchemy and for Saturn in astrology. Why had Planck called it h? Orozco found that it may reference Hilfsgröße, which is the concept of a “helpful quantity.” This helpful quantity has opened a new world of understanding, much as Galileo did when he found that the distance traveled in fixed time intervals on his inclined plane is proportional to odd numbers (1,3,5,7, etc.)—a classical and early lesson in physics.

Trips to the Biblioteca Nazionale,CERN, EGO and the Galileo Museum are shown in these photos by Adam Dirccam, Anthony Giuffre, Stefano Baldassarri, Sean Markey and Cameron Moneypenny.

A major unsolved puzzle in particle physics and cosmology is the apparent asymmetry in the abundance of matter and antimatter in the universe. One condition for such an asymmetry to arise is the breaking of charge-parity (CP) symmetry in laws of interactions amongst particles, resulting in differences in reactions involving partiPhoebe Hamilton, Will Parker, Hassan Jawahery, Yipeng Sun, Manuel Franco Sevilla and Zishuo Yang. cles and antiparticles. CP violation has been observed in particles containing the strange and bottom quarks--kaons and B mesons--and the results conform to the predictions of the Standard Model at the current level of experimental accuracy. However, CP violation in the Standard Model is not sufficient to explain the matter-antimatter asymmetry in the universe. A key goal of the LHCb experiment is to search for additional sources of CP violation beyond the Standard Model. The Standard Model predicts negligible CP violation in decays of particles containing the charm quark, thus any significant effect in charm mesons could be due to new sources of CP violation. Using the data recorded in 2011-2018, the LHCb experiment has observed CP violation in decays of D mesons – mesons made of a charm quark and anti-up quark.
(see https://arxiv.org/abs/1903.08726 and https://home.cern/news/press-release/physics/lhcb-sees-new-flavour-matter-antimatter-asymmetry.) This work was rated a Physics World Breakthrough of the Year finalist for 2019.

Theorists are hard at work to explain the observed CP violation, which is very small but larger than most of the existing predictions within the Standard Model. Failing any Standard Model explanation, this result could open the door to exploring new sources of CP violation beyond the Standard Model.

The LHCb collaboration is now preparing to complete and install the new upgraded detector elements that will significantly enhance the precision of the spectrometer, thus allowing more precise measurements of CP violation and other very rare effects that may arise from particles and interactions that are not present in the Standard Model. The new upgraded detector elements would enable the experiment to operate at higher intensities of the large hadron collider (LHC) and read out the entire detector--millions of sensor signals--at beam collisions that occur every 25 nanoseconds. Over the past six years, the Maryland team in LHCb has been deeply engaged in the design and construction of a charge particle detector, based on silicon sensors, focusing on the development of the electronics that would enable the readout and transfer of the sensor signals. The team is now preparing to complete the construction of the nearly 600 main electronics boards and 2000 auxiliary boards, which will be shipped to CERN for installation in the LHCb experiment starting in Spring of 2020. The experiment is expected to resume operation in 2021.

Janet Das Sarma, who managed the Condensed Matter Theory Center (CMTC) for the last decade, died on December 2, 2019 at the age of 48 years.

She received a diagnosis of stage 4 metastatic cancer in 2016 and was given a four-month life expectancy, but lived 43 months while undergoing nine separate therapies. Despite these grueling protocols, she continued to carry out all her CMTC duties. On October 25th, she was honored at the Physics staff awards luncheon for her comprehensive efforts in moving the CMTC from the Toll to the Atlantic Building. Her disease took a sudden, decisive bad turn in early November, and she died in December at home, looking at her favorite garden.

Janet ensured that CMTC faculty, postdocs, students and visitors could pursue their scientific interests unhindered by bureaucratic inconvenience. Her careful handling of applications and recommendations helped an immense number of CMTC alumni secure their professorial appointments at various institutions.

She regarded as her greatest accomplishment the raising of her sons, Andrew and Matthew.

Ellen D. Williams, a Distinguished University Professor in the Department of Physics and the Institute for Physical Science and Technology at the University of Maryland, has been named a Fellow of the American Association for the Advancement of Science (AAAS). Election as a AAAS Fellow is an honor bestowed upon AAAS members by their peers, because of their scientifically or socially distinguished efforts to advance science or its applications.

“I am honored to receive this award and delighted that it affirms the important role of scientists in providing clear technical assessments to support policy decisions,” Williams said.   

Williams came to UMD in 1981 for a postdoctoral fellowship and rose to the rank of professor by 1991. At Maryland, she established an internationally recognized research program in experimental surface science, exploring fundamental issues in statistical mechanics and nanotechnology. She also pioneered the use of very powerful electron scanning, tunneling microscopes to study the surface of materials like silicon at the atomic level. In 1996, Williams founded the University of Maryland Materials Research Science and Engineering Center, serving as its director until 2009. 

Williams served as the chief scientist for British Petroleum (BP) from 2010 to 2014, before her confirmation by the U.S. Senate as the director of the Advanced Research Projects Agency-Energy (ARPA-E) on Dec. 8, 2014. Launched with bipartisan support in 2009, ARPA-E’s mission is to advance high-potential, high-impact energy technologies that are too early in development for private-sector investment. 

Williams returned to UMD in January 2017. Since then, she has been working to bridge policy and technology perspectives for clean energy innovation. Recently, she completed a report to the State of Maryland on “The Present Status and Future Potential of Maryland’s Clean Energy Innovation System.”

“Dr. Williams is continuing the long tradition of accomplished physicists turning their attention and skills to tackling major policy issues of the day—in her case, climate change and energy policy,” said Steven Rolston, professor and chair of the UMD Department of Physics. “We are lucky to have someone with her talents contributing to these issues, which are among most pressing facing humanity."

Williams has a distinguished history of professional service, including chairing the development of the National Academy of Sciences’ 2002 report on “Technical Issues Related to the Comprehensive Nuclear Test Ban Treaty” and providing extensive technical advice to the U.S. government, primarily through the Departments of Energy and Defense. As a member of the Congressional Commission on the Strategic Posture of the United States, Williams co-authored the 2009 final report titled “America’s Strategic Posture,” which provided more than 100 findings and recommendations on critical issues related to the U.S. nuclear strategy.

Williams received her bachelor's degree in chemistry from Michigan State University in 1976 and her Ph.D. in chemistry from the California Institute of Technology in 1981. She is a member of the National Academy of Sciences and a foreign member of the Royal Society (London). She is also a fellow of the American Academy of Arts and Sciences, the American Physical Society, and the American Vacuum Society. Williams has also been recognized by awards from the American Physical Society and the Materials Research Society.

Williams is one of 443 AAAS members to be named as a Fellow this year. New Fellows will be formally announced in the AAAS News & Notes section of the journal Science on November 29, 2019, and will be presented with an official certificate and a rosette pin on Saturday, February 15, 2020 during the AAAS Annual Meeting in Seattle, Washington.