Spring 2016 STEMinar Schedule

Date:��2/4/2016

��𲹰��:��Phil Orlandini

Department:��ұ�Ǳ��ǲ��

�վ��ٱ��:��Deep rupture: earthquake friction melts far outside of the crustal schizosphere

��ٰ��:��When earthquakes slide along a fault plane in order to relieve tectonic stresses, friction along that fault plane can sometimes become so intense that it will form a flash melt up and down the fault. This flash melt, however, also flash cools – it is typically a sheet of melt >2000 °C with a very large surface area and only centimeters thick at most, and it loses heat so rapidly to the surrounding rocks that it rockets down past its crystallization temperature and becomes a glass. These sheets of glass can then be found later, when that part of the fault reaches the surface, and it can preserve a great deal of information about the moments in which it formed! This has lead to these frictional melts being called ‘fossil earthquakes’. The value of these fossil earthquakes is especially high when they occur when they are not supposed to. To a rock, the earth’s top 20 kilometers or so is very cold, and the rock behaves as a brittle solid that may only relieve inexorable stresses by cracking, sliding, breaking (leading to this portion of the earth being referred to as the ‘schizosphere’ by me and one other person). Below that top 20 kilometers or so, however, the conditions are hot enough for rocks to behave in a plastic fashion – they remain solid and crystalline, but have an appreciable viscosity over geologic time. Because these hotter rocks can flow to some extent, they do not store elastic energy like their colder upper neighbors do, and so typically can diffuse away tectonic strains without ever needing to break and slide and knock people’s houses down. BUT! Sometimes… there are these fossil earthquakes in rocks that were so hot and squishy and flow-y that they basically look like huge outcrops of eight different kinds of toothpaste. But that doesn’t make any sense! How hard it is to shatter room temperature silly-putty with a hammer? And yet, that is what we find. So something is amiss in our understanding of how the earth squishes and/or breaks, and only SCIENCE (coauthored by very expensive instrumentation, literally millions of Canadian blackflies, and a small international cabal) can tell us what it is!

�ٲ��ٱ�:��2/11/2016

��𲹰��:��Yomay Shyur,

�ٱ�貹��ٳ��Գ�:��Physics

�վ��ٱ��:��Cold molecular collisions: Creating space-like conditions in the lab

��ٰ��:��Cold samples of molecules are difficult to create in the laboratory due to the complex energy structures of even the simplest molecules. Recent technological advancements have overcome some of these complexities and allow scientists to create astrophysically relevant cold molecules (such as NH3, OH, CH, NH) in the laboratory. This allows for the study of the quantum mechanics of cold molecular collisions and reactions at temperatures that previously had only been observed by astronomers. We create a trapped samples of cold ammonia (NH3) or OH using a specific combination of electric fields in a process called Stark Deceleration. This method can take a sample of molecules at room temperature (~300 K) down to below 1 K. These specially prepared molecules can then be used to study atom-molecule collisions. I will talk about how we create cold samples of molecules and why we want to recreate space like temperatures in the lab.

�ٲ��ٱ�:��2/25/2016

��𲹰��:��Cliff Blakestad

�ٱ�貹��ٳ��Գ�:��Mathematics

�վ��ٱ��:��Playing with p-Adic numbers

Abstract: Every integer has a unique base 10, or decimal, expansion. What happens when we allow "infinite base 10 integers"? We will explore this question. It turns out things work better when we look at infinite base p integers, with p a prime number. This will lead us to discover a new notion of size for the integers and some strange geometry. Our travels will take us into the land of fractals and the arena of modular arithmetic. In the end, we will see if this journey can't tell us something new about the integers we started with.

�ٲ��ٱ�:��3/3/2016��

��𲹰��:��Pedro Rodriguez

�ٱ�貹��ٳ��Գ�:��Computer Science

�վ��ٱ��:��Creating an artificial intelligence to play a trivia game

��ٰ��:��Quiz Bowl is a academic trivia game played by thousands of students ranging from elementary school to college. In today's talk, I will discuss how creating a machine that plays Quiz Bowl provides an interesting and fun way to study core challenges in artificial intelligence. Some of these challenges have required advancing the state of the art in machine learning, natural language processing, and decision-making in the face of uncertainty. Examples of these challenges include understanding paragraphs of text to predict an answer with deep learning, identifying ways to extract information from knowledge bases like Wikipedia, and creating a Markov Decision Process to decide when to answer a trivia question. Finally, I will touch on other problems that could be solved using a similar methodology.

�ٲ��ٱ�:��3/10/2016

��𲹰��:��Breanne Newell Stamper

�ٱ�貹��ٳ��Գ�:��Integrative Physiology

��ٰ��:��Healthspan and lifespan, does living longer mean being healthier for longer? Almost all organisms age, and as they do the risk of dying increases (except for teenage boys, they’re invincible). Us humans don’t prefer dying, so we have worked really hard to reduce the threats to our existence. We have shelter, improved sanitary conditions (think plumbing), medicine (yup, germs are a thing), increased access to food, hell we’re even jogging. Doing all these things has worked, we’re living longer than we used to. We figured out that improving our environment can make us live longer. Now that we’re living longer, are we also healthier for longer? As we age not only does the risk of dying go up, but the risk of disease and loss of function goes up. This loss of function happens at all levels – from your genes to your muscles. At first the decline in function isn’t too bad. Yeah, you might have some wrinkles and be a little slower to recover (especially from too many beers), but its not so bad, we’re still young right? The functional decline is progressive. Eventually we lose our independence because our bodies and minds are frail, and we get sick. It now becomes apparent that we want to delay and slow this functional decline. We want to extend not only our lifespan but also our period of health (healthspan).

�ٲ��ٱ�:��4/7/2016

��𲹰��:��Hannah Miller

�ٱ�貹��ٳ��Գ�:���ұ�Ǳ��ǲ��

�վ��ٱ��:��Water/rock reactions leading to hydrogen production and its implications for microbial habitability on other planets

��ٰ��:��Iron-bearing (ultramafic) minerals from the earth’s mantle can react with water at low temperatures (<120°C) to form hydrogen gas. The hydrogen formed through these water/rock reactions is a potential electron donor which microorganisms can use as a source of energy when paired with an electron acceptor like sulfate or nitrate. I am investigating how these water/rock reactions proceed at low temperatures by conducting laboratory experiments with ultramafic rock from Oman to measure hydrogen production and probing associated mineralogical changes during reaction. Oman has the largest and best exposure of ultramafic rocks in the world, making it a prime location to both study hydrogen generation at low temperatures and to probe what types of organisms are subsisting off the abundant hydrogen found in subsurface fluids. This work has implications for astrobiology because Oman is an analog for planets like Mars or Europa that contain similar iron-bearing rocks that may be fueling a subsurface biosphere.

�ٲ��ٱ�:��4/14/2016

��𲹰��:��Cliff Bridges

�ٱ�貹��ٳ��Գ�:��Mathematics

�վ��ٱ��:��High stakes legos: Building blocks of a researcher

��ٰ��:��This will be a two-part talk. The first part of this talk will center around the unsolvability of the general quintic polynomial by radicals, and how to (read ``the'') solution to that problem is leading to a deeper understanding of the rational numbers. In particular, we will discuss how a math question that seemed to be answered was then rephrased by a young man, and this rephrasing laid the foundation for nearly 200 years and counting of new research. The second part of this talk will describe the stark absence of particular groups of people in STEM research and what a group of grad students, post docs, and researchers are doing to create stepping stones for people with diverse experiences to come to STEM. Hopefully by the end of this talk you will see that problems which may not affect us directly, or may seem like someone else has already taken care of, can still have a tremendous effect on others and addressing those problems in new and creative ways can build a framework for amazing results that had yet to be dreamed of.

�ٲ��ٱ�:��4/21/2016

��𲹰��:��Kaitlyn Davis

�ٱ�貹��ٳ��Գ�:��Anthropology

�վ��ٱ��:��Protohistoric social networking: What we can learn about inter-regional interaction from design, use-wear, and sourcing analyses of archaeological artifacts

��ٰ��:��Long before Facebook and cell phones, people were leaving material traces of interaction and networking. This presentation provides an overview of archaeological approaches to studying social networks in the past. First, I will discuss the larger scale of regional networks, particularly focusing on least-cost-path analysis and connectivity mapping. Then, I will discuss the smaller scale of tracing the movement of particular artifacts, particularly focusing on material sourcing and artifact dating methods. Finally, I provide a case study example from my thesis research using some of these techniques to trace patterns in interaction between Great Plains and Pueblo people in the American Southwest in the Protohistoric Period (ca. 1450-1700) based on analysis of smoking pipes.

�ٲ��ٱ�:��4/28/2016

��𲹰��:��Matthew Tooth

�ٱ�貹��ٳ��Գ�:��Aerospace Engineering

�վ��ٱ��:��Witnessing the decline of arctic sea ice: How airborne and satellite remote sensing techniques help us understand the current and future states of the arctic sea ice cover

��ٰ��:��Arctic sea ice is on the decline, and we are trending toward a seasonal ice cover that melts and re-forms each year. These changes impact everything from polar bears to oil prices, and aren't isolated from the global climate. How do we know the ice is on the decline? This talk answer that question by introducing some remote sensing techniques that we use to observe sea ice from the air and space, and what information we can get from the data that these techniques provide. In addition, the airborne and model work that we are currently working on in our lab will be discussed. This work involves flying in the Arctic on both NASA and Office of Naval Research flights, which will help us to better observe the condition of the sea ice on small scales. This talk will help provide a brief introduction to this interesting and relevant subject that affects military, babyֱ��app, political, and scientific policy; and I hope you'll gain a new appreciation for the many techniques we use to observe the changing Arctic sea ice.

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Spring 2016 STEMinar Schedule