Radiations Newsletter

Winter Term 2022 Week 9

Gabrielle Evans
Wednesday, March 2 2022
8:30 am in Olin 141
Pole Vaulting
Modern pole vault technique is endogenous to polymer-composite vaulting poles and their characteristic bend. Glass-fiber reinforced plastic and carbon-fiber composites are the current standard for vaulting poles in athletics for their light weight, flexibility and strength. Their composite composition allows for a superior level of control and customization of the pole’s bend and presents a novel engineering opportunity for optimizing vaulting poles’ construction.  This talk will explore elasticity and strength of composite materials through a multi-disciplinary perspective, use these tools to examine the considerations in designing composite material poles and motivate a constitutive equation for vaulting poles.

Kevin Clelland
Wednesday, March 2 2022
3:10 pm in Olin 141
Radiative Cooling: How it Works and Why We Should Paint Everything
With rising global temperatures, the demand for air conditioning in recent years has grown substantially, and is likely about to skyrocket. This poses a considerable challenge for sustainability and decarbonization efforts as air conditioning already accounts for about 10% of global electricity consumption, and the process it uses converts all that electricity into additional heat, resulting in a net increase in the planet’s temperature. Thus, scientists are looking to replace our current air conditioning systems with something more sustainable, that doesn’t have the same electricity demands, and a promising candidate is radiative cooling. Radiative cooling is a process where a building is kept cool by materials on its roof that absorb incoming heat and reemit it at a frequency where it can pass through the atmosphere and out into space without interacting with any of the greenhouse gasses that typically trap heat. Using this process, researchers have been able to match the cooling power of air conditioning, achieving this system with both specially designed reflective panels (2013), and more recently with a highly reflective paint (2021), making it a viable and sustainable alternative to air conditioning going forward.

Pinchen Fan
Friday, March 4 2022
3:30 pm in Olin 141
Gravitational Waves
Gravitational waves (GWs) are tiny ripples in the fabric of spacetime, much like water waves when boats pass by. Collisions of compact binary objects, like neutron stars and black holes, millions of light years away can emit detectable GWs on Earth. The Laser Interferometer Gravitational-Wave Observatory (LIGO) made the first direct detection of GWs on September 14, 2015. That GW changed the lengths of the 4-km LIGO arms by merely a thousandth of the width of a proton. We will start our talk by understanding what GWs are, starting with special relativity and walking through how the Einstein equation predicts GWs. Then, I will explain LIGO’s observing mechanism, focusing on the optical interferometer systems that are used to detect the tiny change in the arm lengths. In the end, I will then briefly discuss what GWs can contribute to our understanding of the universe in general. 

Jan Williams
Monday, March 7 2022
8:30 am  in Olin 141
Acoustic Signals and Sonar Systems
Sensing or imaging underwater environments is a critical task for many sea vessels. As with most imaging systems (medical photography, telescopes, radar systems, etc.), we rely on waves to carry information from which we make an inference about events at a remote location. Underwater imaging systems (most commonly known as SOund NAvigation and Ranging or sonar) are somewhat unique in the fact that they make use of acoustic as opposed to electromagnetic waves. In this talk, we will briefly explore the physics of waves generally and discuss why mechanical waves are a natural choice for underwater imaging systems. We’ll then introduce a few important ideas from signal processing, explain how they are used in sonar, and apply them to a variety of simple acoustic signals.

Please fill out this interest form to let Trenne know!  Please get it in by the end of this week (March 4th).

Hello, physics friends! Thank you to everyone who submitted t-shirt design ideas! We now need all of your help deciding on which design to use this year. Some of them are…

The physics IDEA (Inclusion, Diversity, and Equity Alliance) team wants to hear about your experiences in the physics department. Fill out this short survey so we can understand what makes the Physics Department more or less inclusive, with the goal to enact ongoing positive change and growth. Please complete this survey by the last day of finals, March 16^th!

Join APS and Physical Review D for a special event held in conjunction with the APS April Meeting 2022 —Expanding Space in Astrophysics: A Wikipedia Edit-a-thon. This virtual event will…

The Department of Homeland Security (DHS) Secretary’s Honors Program (SHP) is offering summer paid internship opportunities to undergraduate and graduate students in cybersecurity and business operations. Internships will be available…