Events

Claire Zukowski, Assistant Professor, UMD Swenson College of Science and Engineering

Quantum gravity aims to combine the quantum physics relevant at scales below the size of an atom with Einstein’s theory of gravity, which applies at the largest scales. This is crucial for understanding regimes where a large amount of gravitating mass is compressed to a tiny distance scale, for instance near the singularity of a black hole or close to the Big Bang that populated our universe. Holography gives a realization of quantum gravity through explicit dualities between quantum physics and gravity. After giving an overview of this framework, I will show how several geometrical aspects of gravity are emergent from quantum physics. Importantly, my focus will be on a geometry called de Sitter spacetime, which closely resembles our actual universe.

Speaker: Michael Coughlin, Assistant Professor, School of Physics and Astronomy, UMN

With the detection of compact binary coalescences and their

electromagnetic counterparts by gravitational-wave detectors, a new
era of multi-messenger astronomy has begun. In this talk, I will
describe how the gravitational-wave community is using these mergers
to constrain the unknown equation of state of cold supranuclear
matter, and to measure the Hubble constant. I will then discuss how
current ground based optical surveys and dedicated follow-up systems
are being used to identify more of these, and how we are developing
models to test what we find. We will close with near-term prospects
for the field.

Physics & Astronomy alums will share an overview of their academic and career paths post Mac, and answer your questions about their choices:

• Peter West, ‘93 - Polar Semiconductor
• Korey Haynes, ‘09 - Astronomy Magazine
• Jason Beal, ‘22 - Ramboll
• Ross Ferguson, ‘23 - UMN Physics PhD Program
  
  
  

Eric Hazlett, Visiting Assistant Professor of Physics at St Olaf is presenting:

When people think about physics their thoughts go to complicated mathematics and or experiments. Often, they view themselves as unable to do this. This barrier is propagated by the media and pop culture and can create inequalities and obstacles to inclusion and belonging. By engaging with the community, we can combat these stereotypes and enable more people to enjoy physics and science. I will discuss my path to this current state of our community engagement efforts at St. Olaf and discuss the future plans for expansion in the budding field of Informal Physics Education.

Be inspired as current physics and astronomy students reflect on conducting research this past summer and their unique projects. Learn about the different types of projects available for Mac students, both on campus and farther afield. Find out how these opportunities came about, and what the overall experience was like for the students participating. This seminar will be particularly helpful for first- and second-year students curious about research, and those looking to better understand what to expect and how to get involved.

Joint Chemistry and Physics Special Lecture:

Zach Fried (Mac '21)

Zach is an astrochemist who seeks to understand the physical and chemical processes that occur in space. Until recently, in order to model interstellar abundances and predict new molecules for detection, observations have relied on complex chemical models based on a vast network of interconnected reactions. Zach's research group has developed a method involving machine learning that requires no prior knowledge of the interstellar conditions or reaction pathways. He is working to expand these machine learning techniques by including isotopically substituted molecules that provide important insight into molecular formation and astrophysical history. He hopes to apply machine learning methods to increase the efficiency and automation of rotational spectroscopy.

Join us for this week's Physic Seminar Special Lecture by:
Macalester Professor John Cannon

Macalester is entering the second full observing season as a founding member of the MACRO Consortium, which operates the Robert L. Mutel Telescope (RLMT) located in Arizona.  This robotic telescope is transforming the way we teach astronomy here at Macalester and offering our students an even broader range of research opportunities, from telescope operating software creation to student-driven research topics.  Prof. Canon will introduce the RLMT, and share the exciting ways that students from across the Consortium are benefiting from access to this remote observatory.

Professor Renee Sher, Wesleyan University is presenting.

Organic-inorganic hybrid perovskite solar cells have set efficiency records at least once a year in the past decade. This material offers numerous possibilities and  presents several mysteries. Among them, the optical properties are widely tunable by mixing halide compositions, but at the same time halide segregation under illumination reversibly changes the material. In my group, we use terahertz  spectroscopy as a non-contact conductivity probe with excellent time resolution  as a tool for studying advanced solar cell materials. This talk will focus on how we  use election’s local motion to understand why the inclusion of inorganic cations helps achieve high efficiencies in solar cells and to probe the local environment in  wide-bandgap mixed-halide perovskites.

Refreshments at 3 PM.

The Physics & Astronomy Department invites you to attend the last senior honors thesis presentation of the semester:

Sylvia Greene: "Simulation of Polymerization on Surfaces: Implications for Abiogenesis."

All are welcome! 

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend another senior honors thesis presentation:

Nick Cebula: "Variability in Mode Parameters of Solar Acoustic Oscillations."

All are welcome! 

Refreshments at 3 p.m

The Physics & Astronomy Department invites you to attend a senior capstone presentation:

Ally Hurd: "Probing Charge Recombination in Organic Solar Cells."

All are welcome!

The Physics & Astronomy Department invites you to attend another senior honors thesis presentation:

Olivia X. Laske: "Linking the Population of Binary Black Holes with the Stochastic Gravitational-Wave Background."

All are welcome! 

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend another senior honors thesis presentation:

• Uditi Chandrashekhar: "The Hodgkin-Huxley Model for Neuron Action Potentials: A Computational Study."
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All are welcome! 

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend their senior honors thesis  presentation:

• Charlie Burton: "Ammonia Emission from the Milky Way Galactic Bar Dust Lanes."
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• All are welcome! 
  

The Physics & Astronomy Department invites you to attend their senior honors thesis  presentation:

• Seth Buesing: "Mapping beyond-Landau phase transitions in 1+1dimensional U(1) field theories."

All are welcome! 

Refreshments at 3 p.m.

Ben Augenbraun, Assistant Professor of Chemistry at Williams College will present on "Golden Opportunities: From Ultracold Molecules to Insights about Catalysis" in a joint Chemistry and Physics and Astronomy seminar. A recent triumph of physical chemistry has been to trap molecules at ultracold temperatures in “beakers” made of laser light. It is hoped that this will enable advances in quantum information science, precision measurement, and ultracold chemistry. In this talk, Augenbraun will first review recent work on molecular laser cooling. He will then discuss efforts at Williams College to identify new, complex molecules that can be cooled and trapped.

The Physics & Astronomy Department invites you to attend its upcoming senior honors thesis  presentation:

Caleb Williams: "A Survey of Pulsed Strain in NMR Based Nematic Susceptibility Measurements."

All are welcome! 

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend their senior capstone presentations:

• Max Zinman: "Carrier Mobilities in Perovskite Solar Cells;"
• Ishan Rayen: "Effects of Annealing on Room Temperature Deposited Zinc Oxide."

All are welcome! 

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend their senior capstone presentation:

• Siri Erickson-Green: "Investigation of Tantalum Lead Borate Glass using LITOF-MS."

All are welcome! 

Refreshments at 3 p.m.

Dr. Elena Sabbi, Deputy Head, Science Mission Office, Space Telescope Science Institute is presenting.

Star formation is a complex, multiscale process affected both by local and global factors. Modern models of molecular cloud collapse now incorporate variables such as stellar feedback, magnetic field, gas and dust temperature, galaxy sheer, galaxy mergers, etc., enabling the formation of loose associations and rich star clusters. However, the limited observational constraints hinder our ability to validate these models. I will discuss how characterizing the internal kinematics of young star clusters in the Local Group can provide insights into the assembly process of regions undergoing massive star formation. Additionally, I will demonstrate how multiwavelength studies of resolved stellar populations in galaxies in the local universe can reveal the dissolution dynamics of regions of recent star formation within the parent galaxy’s field, suggesting potential dissolution timescales.

Refreshments at 3 PM.

Hosted jointly by the Physics and Astronomy Student Group and the Environmental Studies Department. Join us in John B. Davis Hall located in the Campus Center. We will watch the documentary 2040 directed by Damon Gameau. 

Dr. Alexandra Le Reste, Postdoctoral Research Associate, School of Physics and Astronomy University of Minnesota, will present " What nearby galaxies teach us about the beginning of the Universe."

The Universe changed drastically during its first billion year as neutral hydrogen gas, which filled the intergalactic space, became ionized. This last major phase transition of the Universe is an important cosmological period known as the Epoch of Reionization. Simulations and new observations using powerful telescopes indicate that primordial galaxies were the main sources of the ionizing UV photons responsible for Reionization. However, many unknowns remain on the mechanisms that enabled these photons to escape the neutral interstellar medium of galaxies to ionize the space around them on much larger scales. Here, I will show how we can use observations of nearby galaxies to understand the physical processes that caused cosmological reionization. In particular, we will see what observations of the neutral gas reservoirs of rare local galaxies analogous to objects in the early universe teach us about the potential role of galaxy interactions during the Epoch of Reionization.

Refreshments at 3 p.m.

Bennett McNulty, McKnight Land-Grant Professor, Department of Philosophy, University of Minnesota will speak on "Kant’s Aethereal Hammer: When Everything Looks Like a Nail."

Throughout Immanuel Kant’s works on natural philosophy, he utilizes an omnipresent aether to explain a wide variety of physical events: including optical, thermodynamical, chemical, and magnetic phenomena. Kant even went as far as claiming that the existence of an omnipresent physical aether can be deduced a priori (without appeal to experience, observation, or experiment), in the notorious “aether proof” of his Opus postumum. In retrospect, these commitments are widely seen as a blunder, especially after the demise of the luminiferous aether at the turn of the 20th century.

Refreshments at 3 p.m. 

LIGO and the Detection of Gravitational Waves: A Film by Les Guthman

The thrilling, award-winning, inside story of the discovery that topped NATIONAL GEOGRAPHIC's list of “The top 20 Scientific Discoveries of the Decade," the Nobel Prize-winning discovery of gravitational waves from deep space, 2015-2017.

Two discoveries two years apart, which opened a radical new era in astronomy. First, two colliding black holes and then the discovery of two crashing neutron stars and their spectacular light show opened up the 95% of the universe that had been dark to our existing observatories and space telescopes. It's the violent "warped side" of the universe predicted by Einstein -- but never seen until now.

Director Les Guthman witnessed and filmed this dramatic and emotional peak in the lives of the1,000 scientists around the world who risked their careers on a 40-year, $1 billion search for these exquisite messengers from the warped side.

Refreshments at 3 PM.

Dr. James Marti, Senior Scientist & Outreach Coordinator, Nano Center, University of Minnesota is speaking about Nanoscience Research at the University of Minnesota.

"Nanoscience and applied nanotechnology have attracted interest from scientists, engineers, and the general public for decades. But what is nanotechnology, and why would someone want to do research in the field of nanoscience? This presentation will offer an introduction to nanoscience and nanotechnology, present a summary of some of the current nanoscience research focus areas at Minnesota, and describe opportunities for faculty and students from other institutions to collaborate with the Nano Center."

Dr. Marti directs the Center’s Nanomaterials and Bio-Nano Labs, which focus on developing and analyzing nanoparticles and exploring their potential biomedical applications.

Refreshments at 3 p.m.

Professor Tonnis ter Veldhuis, Department of Physics & Astronomy, Macalester College is presenting on "Double copy: a new look at scattering amplitudes."

The calculation of scattering amplitudes is essential to the field of high energy physics, since amplitudes provide the bridge between theoretical quantum field theory models and detector results from particle accelerator experiments.  Recent advances in this area have uncovered novel color-kinematics and double-copy structures in theories ranging from gauge and gravity theories to effective field theories. I will provide an introduction to these new developments and relate my own contribution in this area made during my sabbatical leave at the University of Groningen, namely a systematic classification of scalar field theories whose amplitudes admit a double copy formulation.

Refreshments at 3 p.m.

Professor Tonnis ter Veldhuis, Department of Physics & Astronomy, Macalester College is presenting on "Double copy: a new look at scattering amplitudes."

The calculation of scattering amplitudes is essential to the field of high energy physics, since amplitudes provide the bridge between theoretical quantum field theory models and detector results from particle accelerator experiments.  Recent advances in this area have uncovered novel color-kinematics and double-copy structures in theories ranging from gauge and gravity theories to effective field theories. I will provide an introduction to these new developments and relate my own contribution in this area made during my sabbatical leave at the University of Groningen, namely a systematic classification of scalar field theories whose amplitudes admit a double copy formulation.

Refreshments at 3 p.m.

Four Physics & Astronomy alums will give an overview of their career paths since leaving Macalester and answer your questions about their choices.

·         Emmy Curtis, '21 - Great Plains Institute

·         Nate Davies, '20 - PAR Systems

·         Jeff Rodgers, '07 - Concord USA

·         Elena Youngdale, '20 - TCC Materials

Refreshments at 3 PM. 

Professor Uwe Korsthagen, University of Minnesota, Distinguished McKnight University Professor and Ronald L. and Janet A. Christenson Chair in Renewable Energy, Mechanical Engineering is presenting.

Chemically reactive nonthermal plasmas at low pressure are an interesting medium for the growth of nanocrystals. Molecular precursors are dissociated by electron impact reactions and the resulting molecular fragments and radicals, many of them charged, nucleate to form clusters and nanocrystals. Energetic surface reactions heat these initial clusters to temperatures that exceed the gas temperature by hundreds of Kelvin. This enables plasmas to form crystalline nanoparticles even of materials with very high melting points.

In this presentation, we will discuss the plasma synthesis of silicon quantum dots with diameters on the order of ~3 nm for luminescent applications as well as the synthesis of larger silicon nanocrystals, 60-200 nm in diameter, that show interesting scattering behaviors.

Refreshments at 3 p.m.

Summer researchers presenting:

Camellia Schwartzman, "Synthesizing Nanowires from both Top-down and Bottom-up Approaches"
Lila Schisgal, "Low Mass Galaxies NGC5238 and DDO68"
Cain Rinkoski, "Galactic Magnetic Fields: Studying NGC4490/85"
Justin Potts, "Optimizing Strain Characterization of Graphene Using Raman Spectroscopy"
Rohan Lichtenberg, "Electro-optical Detection of Plasma Generated Terahertz-Radiation"

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend their final senior capstone presentations of the spring semester:

• Ezra Wolf: "Tools for Refining the Baryonic Tuller-Fisher Relation"
• Dengyu (Spud) Tu: "From Experiment to Theory: Time-Resolved Photoconductivity Measurements and 3D Approximation Methods to Investigate the Effect of Pump Beam Size on Photovoltaic Material Behavior"

All are welcome! 

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend a senior honors thesis presentation:

• Chloe Zheng: "Development of a Particle-in-Cell/Monte Carlo Simulation for Weakly Ionized Plasmas."

All are welcome!

The Physics & Astronomy Department invites you to attend a senior honors thesis presentation:

• David Geeganage: "Using Models of Cloud Formation to Address the RH Effect in Low Cost PM Sensors."

All are welcome!

The Physics & Astronomy Department invites you to attend a senior honors thesis presentation:

• Ross Ferguson: "Trinification with a Bi-Adjoint Higgs Field."

All are welcome!

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend a senior honors thesis presentation:

• Jackson Codd: "Extension of the LUX-ZEPLIN NR Background to 600 phd for Dark Matter Detection."

All are welcome!

Refreshments at 3 p.m.

The Physics & Astronomy Department invites you to attend a senior honors thesis presentation:

• Haoxuan Sun ► "Machine Learning Refinements to Metallicity-Dependent Isotopic Abundance."

All are welcome!

Refreshments at 3 p.m.