From The College of Science and Engineering
At
The University of Minnesota-Twin Cities
5.11.23
Savannah Erdman
University Public Relations
612-624-5551
erdma158@umn.edu
Credit: Patrick Kelly, University of Minnesota.
Thanks to data from a magnified supernova, a team led by University of Minnesota researchers has successfully used a first-of-its-kind technique to measure the expansion rate of the Universe. Their data provide insight into a longstanding debate in the field of astronomy and could help scientists more accurately determine the Universe’s age and better understand the cosmos.
The work is divided into two papers, published in Science [below], one of the world’s top peer-reviewed academic journals, and The Astrophysical Journal [below], a peer-reviewed scientific journal of astrophysics and astronomy.
In astronomy, there are two precise measurements of the expansion of the Universe, also called the “Hubble constant.” One is calculated from nearby observations of supernovae, and the second uses the “cosmic microwave background,” or radiation that began to stream freely through the Universe shortly after the Big Bang.
However, these two measurements differ by about 10%, which has caused widespread debate among physicists and astronomers. If both measurements are accurate, that means scientists’ current theory about the make-up of the universe is incomplete.
“The big question is if there is a possible issue with one or both of the measurements. Our research addresses that by using an independent, completely different way to measure the expansion rate of the Universe,” said Patrick Kelly, lead author of both papers and an assistant professor in the College of Science and Engineering.
The team was able to calculate this value using data from a supernova discovered by Kelly in 2014 — the first ever example of a multiply imaged supernova, meaning that the telescope captured four different images of the same cosmic event. After the discovery, teams around the world predicted that the supernova would reappear at a new position in 2015, and the University of Minnesota team detected this additional image [see image below].
These multiple images appeared because the supernova was gravitationally lensed by a galaxy cluster, a phenomenon in which mass from the cluster bends and magnifies light.
By using the time delays between the appearances of the 2014 and 2015 images, the researchers were able to measure the Hubble constant using a theory developed in 1964 by Norwegian astronomer Sjur Refsdal that had previously been impossible to put into practice.
The researchers’ findings don’t absolutely settle the debate, Kelly said, but they do provide more insight into the problem and bring physicists closer to obtaining the most accurate measurement of how old the Universe is.
“Our measurement is in better agreement with the value from the cosmic microwave background, although — given the uncertainties — it does not rule out the measurement from the local distance ladder,” Kelly said. “If observations of future supernovae that are also gravitationally lensed by clusters yield a similar result, then it would identify an issue with the current supernova value, or our understanding of galaxy-cluster dark matter.”
Using the same data, the researchers found that some current models of galaxy-cluster dark matter were able to explain their observations of the supernovae. This allowed them to determine the most accurate models for the locations of dark matter in the galaxy cluster, a question that has long plagued astronomers.
Science
The Astrophysical Journal
Figure 1. Image of the MACS J1149 galaxy-cluster field and the locations and timing of the appearances of SN Refsdal. A first appearance occurred according to model predictions in the host galaxy image at the upper left in the late 1990s but was missed. We detected images S1–S4 in an Einstein-cross configuration in 2014November (Kelly et al. 2015). Following this appearance, lens modelers predicted the SN’s reappearance, which was detected in late 2015 (Kelly et al. 2016c). Inset at upper right shows a co-added WFC3 IR F125W image of the field following the reappearance of the SN in image SX.
This research was funded primarily by NASA through the Space Telescope Science Institute and the National Science Foundation.
See the full article here .
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The College of Science and Engineering (CSE) is one of the colleges of the University of Minnesota in Minneapolis, Minnesota. On July 1, 2010, the college was officially renamed from the Institute of Technology (IT). It was created in 1935 by bringing together the University’s programs in engineering, mining, architecture, and chemistry. Today, CSE contains 12 departments and 24 research centers that focus on engineering, the physical sciences, and mathematics.
Departments
Aerospace Engineering and Mechanics
Biomedical Engineering
Chemical Engineering and Materials Science
Chemistry
Civil, Environmental, and GeoEngineering
Computer Science and Engineering
Earth Sciences (formerly called Geology and Geophysics)
Electrical and Computer Engineering
Industrial and Systems Engineering
Mathematics
Mechanical Engineering
Physics and Astronomy
Additionally, CSE pairs with other departments at the University to offer degree-granting programs in:
Bioproducts and Biosystems Engineering, with CFANS (formerly two departments: Biosystems and Agricultural Engineering, and Bio-based Products)
Statistics
And two other CSE units grant advanced degrees:
Technological Leadership Institute (formerly Center for the Development of Technological Leadership)
History of Science and Technology
Research centers
BioTechnology Institute
Characterization Facility
Charles Babbage Institute – CBI website
Digital Technology Center
William I. Fine Theoretical Physics Institute
Industrial Partnership for Research in Interfacial and Materials Engineering
Institute for Mathematics and its Applications
Minnesota Nano Center
NSF Engineering Research Center for Compact and Efficient Fluid Power
NSF Materials Research Science and Engineering Center
NSF Multi-Axial Subassemblage Testing (MAST) System
NSF National Center for Earth-surface Dynamics (NCED)
The Polar Geospatial Center
Center for Transportation Studies
University of Minnesota Supercomputing Institute
GroupLens Center for Social and Human-Centered Computing
Educational centers
History of Science and Technology
School of Mathematics Center for (K-12) Educational Programs
Technological Leadership Institute
UNITE Distributed Learning
The University of Minnesota Twin Cities is a public research university in Minneapolis and Saint Paul, MN. The Twin Cities campus comprises locations in Minneapolis and St. Paul approximately 3 miles (4.8 km) apart, and the St. Paul location is in neighboring Falcon Heights. The Twin Cities campus is the oldest and largest in The University of Minnesota (US) system and has the sixth-largest main campus student body in the United States, with 51,327 students in 2019-20. It is the flagship institution of the University of Minnesota System, and is organized into 19 colleges, schools, and other major academic units.
The Minnesota Territorial Legislature drafted a charter for The University of Minnesota as a territorial university in 1851, seven years before Minnesota became a state. Today, the university is classified among “R1: Doctoral Universities – Very high research activity”. The University of Minnesota is a member of The Association of American Universities (US) and is ranked 17th in research activity, with $954 million in research and development expenditures in the fiscal year 2018. In 2001, the University of Minnesota was included in a list of Public Ivy universities, which includes publicly funded universities thought to provide a quality of education comparable to that of the Ivy League.
University of Minnesota faculty, alumni, and researchers have won 26 Nobel Prizes and three Pulitzer Prizes. Among its alumni, the university counts 25 Rhodes Scholars, seven Marshall Scholars, 20 Truman Scholars, and 127 Fulbright recipients. The University of Minnesota also has Guggenheim Fellowship, Carnegie Fellowship, and MacArthur Fellowship holders, as well as past and present graduates and faculty belonging to The American Academy of Arts and Sciences , The National Academy of Sciences, The National Academy of Medicine, and The National Academy of Engineering. Notable University of Minnesota alumni include two vice presidents of the United States, Hubert Humphrey and Walter Mondale, and Bob Dylan, who received the 2016 Nobel Prize in Literature.
The Minnesota Golden Gophers compete in 21 intercollegiate sports in the NCAA Division I Big Ten Conference and have won 29 national championships. As of 2021, Minnesota’s current and former students have won a total of 76 Olympic medals.
The University of Minnesota was founded in Minneapolis in 1851 as a college preparatory school, seven years prior to Minnesota’s statehood. It struggled in its early years and relied on donations to stay open from donors including South Carolina Governor William Aiken Jr.
In 1867, the university received land grant status through the Morrill Act of 1862.
An 1876 donation from flour miller John S. Pillsbury is generally credited with saving the school. Since then, Pillsbury has become known as “The Father of the University.” Pillsbury Hall is named in his honor.
Academics
The university is organized into 19 colleges, schools, and other major academic units:
Center for Allied Health Programs
College of Biological Sciences
College of Continuing and Professional Studies
School of Dentistry
College of Design
College of Education and Human Development
College of Food, Agricultural and Natural Resource Sciences
Graduate School
Law School
College of Liberal Arts
Carlson School of Management
Medical School
School of Nursing
College of Pharmacy
Hubert H. Humphrey School of Public Affairs
School of Public Health
College of Science and Engineering
College of Veterinary Medicine
Institutes and centers
Six university-wide interdisciplinary centers and institutes work across collegiate lines:
Center for Cognitive Sciences
Consortium on Law and Values in Health, Environment, and the Life Sciences
Institute for Advanced Study, University of Minnesota
Institute for Translational Neuroscience
Institute on the Environment
Minnesota Population Center
In 2021, the University of Minnesota was ranked as 40th best university in the world by The Academic Ranking of World Universities (ARWU), which assesses academic and research performance. The same 2021 ranking by subject placed The University of Minnesota’s ecology program as 2nd best in the world, its management program as 10th best, its biotechnology program as 11th best, mechanical engineering and medical technology programs as 14th best, law and psychology programs as 19th best, and veterinary sciences program as 20th best. The Center for World University Rankings (CWUR) for 2021-22 ranked Minnesota 46th in the world and 26th in the United States. The 2021 Nature Index, which assesses the institutions that dominate high quality research output, ranked Minnesota 53rd in the world based on research publication data from 2020. U.S. News and World Report ranked Minnesota as the 47th best global university for 2021. The 2022 Times Higher Education World University Rankings placed Minnesota 86th worldwide, based primarily on teaching, research, knowledge transfer and international outlook.
In 2021, The University of Minnesota was ranked as the 24th best university in the United States by The Academic Ranking of World Universities, and 20th in the United States in Washington Monthly’s 2021 National University Rankings. The University of Minnesota’s undergraduate program was ranked 68th among national universities by U.S. News and World Report for 2022, and 26th in the nation among public colleges and universities. The same publication ranked The University of Minnesota’s graduate Carlson School of Management as 28th in the nation among business schools, and 6th in the nation for its information systems graduate program. Other graduate schools ranked highly by U.S. News and World Report for 2022 include The University of Minnesota Law School at 22nd, The University of Minnesota Medical School, which was 4th for family medicine and 5th for primary care, The University of Minnesota College of Pharmacy, which ranked 3rd, The Hubert H. Humphrey School of Public Affairs, which ranked 9th, The University of Minnesota College of Education and Human Development, which ranked 10th for education psychology and special education, and The University of Minnesota School of Public Health, which ranked 10th.
In 2019, The Center for Measuring University Performance ranked The University of Minnesota 16th in the nation in terms of total research, 29th in endowment assets, 22nd in annual giving, 28th in the number of National Academies of Sciences, Engineering and Medicine memberships, 18th in its number of faculty awards, and 14th in its number of National Merit Scholars. Minnesota is listed as a “Public Ivy” in 2001 Greenes’ Guides The Public Ivies: America’s Flagship Public Universities.
Media
The Minnesota Daily has been published twice a week during the normal school season since the fall semester 2016. It is printed weekly during the summer. The Daily is operated by an autonomous organization run entirely by students. It was first published on May 1, 1900. Besides everyday news coverage, the paper has also published special issues, such as the Grapevine Awards, Ski-U-Mah, the Bar & Beer Guide, Sex-U-Mah, and others.
A long-defunct but fondly remembered humor magazine, Ski-U-Mah, was published from about 1930 to 1950. It launched the career of novelist and scriptwriter Max Shulman.
A relative newcomer to the university’s print media community is The Wake Student Magazine, a weekly that covers UMN-related stories and provides a forum for student expression. It was founded in November 2001 in an effort to diversify campus media and achieved student group status in February 2002. Students from many disciplines do all of the reporting, writing, editing, illustration, photography, layout, and business management for the publication. The magazine was founded by James DeLong and Chris Ruen. The Wake was named the nation’s best campus publication (2006) by The Independent Press Association.
Additionally, The Wake publishes Liminal, a literary journal begun in 2005. Liminal was created in the absence of an undergraduate literary journal and continues to bring poetry and prose to the university community.
The Wake has faced a number of challenges during its existence, due in part to the reliance on student fees funding. In April 2004, after the Student Services Fees Committee had initially declined to fund it, the needed $60,000 in funding was restored, allowing the magazine to continue publishing. It faced further challenges in 2005, when its request for additional funding to publish weekly was denied and then partially restored.
In 2005 conservatives on campus began formulating a new monthly magazine named The Minnesota Republic. The first issue was released in February 2006, and funding by student service fees started in September 2006.
Radio
The campus radio station, KUOM “Radio K,” broadcasts an eclectic variety of independent music during the day on 770 kHz AM. Its 5,000-watt signal has a range of 80 miles (130 km), but shuts down at dusk because of Federal Communications Commission regulations. In 2003, the station added a low-power (8-watt) signal on 106.5 MHz FM overnight and on weekends. In 2005, a 10-watt translator began broadcasting from Falcon Heights on 100.7 FM at all times. Radio K also streams its content at http://www.radiok.org. With roots in experimental transmissions that began before World War I, the station received the first AM broadcast license in the state on January 13, 1922, and began broadcasting as WLB, changing to the KUOM call sign about two decades later. The station had an educational format until 1993, when it merged with a smaller campus-only music station to become what is now known as Radio K. A small group of full-time employees are joined by over 20 part-time student employees who oversee the station. Most of the on-air talent consists of student volunteers.
Television
Some television programs made on campus have been broadcast on local PBS station KTCI channel 17. Several episodes of Great Conversations have been made since 2002, featuring one-on-one discussions between University faculty and experts brought in from around the world. Tech Talk was a show meant to help people who feel intimidated by modern technology, including cellular phones and computers.
sciencesprings 