Optimization of the magnetic dynamo

In stars and planets, magnetic fields are believed to originate from the motion of electrically conducting fluids in their interior, through a process known as the dynamo mechanism. In this Letter, an optimization procedure is used to simultaneously address two fundamental questions of dynamo theory: "Which velocity field leads to the most magnetic energy growth?" and "How large does the velocity need to be relative to magnetic diffusion?" In general, this requires optimization over the full space of continuous solenoidal velocity fields possible within the geometry. Here the case of a periodic box is considered. Measuring the strength of the flow with the root-mean-square amplitude, an optimal velocity field is shown to exist, but without limitation on the strain rate, optimization is prone to divergence. Measuring the flow in terms of its associated dissipation leads to the identification of a single optimal at the critical magnetic Reynolds number necessary for a dynamo. This magnetic Reynolds number is found to be only 15% higher than that necessary for transient growth of the magnetic field.Comment: Optimal velocity field given approximate analytic form. 4 pages, 4 figure

A Search For Star Formation in the Smith Cloud

Motivated by the idea that a subset of HVCs trace dark matter substructure in the Local Group, we search for signs of star formation in the Smith Cloud, a nearby ~2x10^6 Msun HVC currently falling into the Milky Way. Using GALEX NUV and WISE/2MASS NIR photometry, we apply a series of color and apparent magnitude cuts to isolate candidate O and B stars that are plausibly associated with the Smith Cloud. We find an excess of stars along the line of sight to the cloud, but not at a statistically significant level relative to a control region. The number of stars found in projection on the cloud after removing an estimate of the contamination by the Milky Way implies an average star formation rate surface density of 10^(-4.8 +/- 0.3) Msun yr^(-1) kpc^(-2), assuming the cloud has been forming stars at a constant rate since its first passage through the Milky Way ~70 Myr ago. This value is consistent with the star formation rate expected based on the average gas density of the cloud. We also discuss how the newly discovered star forming galaxy Leo P has very similar properties to the Smith Cloud, but its young stellar population would not have been detected at a statistically significant level using our method. Thus, we cannot yet rule out the idea that the Smith Cloud is really a dwarf galaxy.Comment: 9 pages, 7 figures, accepted for publication in MNRA

Ellen DeGeneres\u27 Tulane Commencement Speech: Is She Getting Through to Anybody?

In this paper, I analyze the commencement speech given by Ellen DeGeneres at Tulane University in 2009. I argue that through identifying with her audience and employing a rhetorical style consisting of a careful balance between humor and tragedy as an additional factor to her use of the commencement genre style presented in Margaret LaWare’s essay, Redefining The \u27Good Life\u27: Life Lessons And Virtues In Commencement Speeches By Women,” DeGeneres is able to establish enough ethos to be seen as a highly credible source on the subject of life, and is able to resonate with her audience and make a point they perceive to be widely reasonable and sound

Amortized Bayesian Inference for Supernovae in the Era of the Vera Rubin Observatory Using Normalizing Flows

The Vera Rubin Observatory, set to begin observations in mid-2024, will increase our discovery rate of supernovae to well over one million annually. There has been a significant push to develop new methodologies to identify, classify and ultimately understand the millions of supernovae discovered with the Rubin Observatory. Here, we present the first simulation-based inference method using normalizing flows, trained to rapidly infer the parameters of toy supernovae model in multivariate, Rubin-like datastreams. We find that our method is well-calibrated compared to traditional inference methodologies (specifically MCMC), requiring only one-ten-thousandth of the CPU hours during test time.Comment: 5 pages, accepted in the Neurips Machine Learning and the Physical Sciences conferenc

Junky to Healthy

Eating healthy is not always easy. In fact it can be quite challenging especially if you think you are alone. A support group is a great way to feel like you are not alone. This is not your average support group. Since I am a little rough around the edges, you could say the support group is too. It does have structure because I want it to succeed but people can yell, scream, cuss and throw squishy balls at the wall

Life, Love, and Lost Smiles

This collection is a compilation of poetry, non-fiction and fiction writing. The works in this collection are inspired by many subjects including personal lifetime events, friends, dreams and more. This collection, entitled “Life, Love & Lost Smiles” symbolizes some of the many things that have personally shaped my life and helped me become not only the writer, but the person that I am today

Study of Workforce Development at WPI/QCC Lab for Education and Application Prototypes (LEAP) in Central MA -- Its Role on Silicon Photonics and Electronics Industries in New England

One major role of WPI/QCC LEAP is to enhance the photonics workforce development in the ecosystem of industry, academia, and government. However, the needs, existing resources, and gaps in Central Massachusetts in integrated photonics are poorly understood, making the LEAP roadmap planning difficult. This work aims to close this knowledge gap. The student team will conduct surveys and interviews in the ecosystem, particularly on the Quinsigamond Community College campus. The outcome will provide understanding of the roles of LEAP in Central Massachusetts and further provide suggestions on the roadmap of Integrated Photonics