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Building Blocks for Communication Over Noisy Quantum Networks
No full textCapacity of a quantum channel characterizes the limits of reliable communication through a noisy quantum channel. This fundamental information theoretic question is very well studied specially in the setting of many independent uses of the channel. An important scenario, both from practical and conceptual point of view, is when the channel can be used only once. This is known as the one-shot channel coding problem. We provide a tight characterization of the one-shot entanglement assisted classical capacity of a quantum channel. We arrive at our result by introducing a simple decoding technique which we refer to as position-based decoding. We also consider two other important quantum network scenarios: quantum channel with a jammer and quantum broadcast channel. For these problems, we use the recently introduced convex split technique [Anshu, Devabathini and Jain 2014] in addition to position based decoding. Our approach exhibits that the simultaneous use of these two techniques provides a uniform and conceptually simple framework for designing communication protocols for quantum networks.Accepted Manuscrip
Sacred Nature: Metaphysics of Place in William Blake, Emily Dickinson and Seamus Heaney
No full textAbstract
William Blake, Emily Dickinson and Seamus Heaney are read as practitioners of ecopoetry (in Jonathan Bate’s phrase) and ecotheology. Where each poet locates the sacred is plotted against their depictions of the natural world. How do they see nature; how do they see the divine; and do these views intersect? The Introduction considers a broad history of immanence and transcendence as two roads to the divine. Blake’s historical contexts, in the pagan tradition of the sacred landscape, and the antinomianism of eighteenth-century Britain, including the Moravian sect, are applied to his prophetic books, chiefly Milton and Jerusalem. Blake’s complex and changing view of nature aspires to a reconciliation of the immanent and the transcendent. From Dickinson’s milieu, the Puritan origins of New England and the American sublime, she cultivated poems which view snakes, bees and hummingbirds as “Nature’s People.” This most idiosyncratic of poets brought forth a new aesthetic, the impersonal sublime. Dickinson is also read as an apophatic poet, her lyrics petals around a generative nothing. Heaney digs from the bogland of history ancient queens and sacrifices, wedding them to the poetic tradition of the aisling in his contemporary moment of northern Ireland’s Troubles. Heaney further believes in an ontological power of language to create and shape landscape itself. Blake’s, Dickinson’s and Heaney’s visions of nature and the sacred number among the threads we may weave into a new relation to the nonhuman world, here on the brink of the sixth great extinction
Resonant Simulacra: Building Artificially Intelligent Instruments, a Portfolio of Musical Compositions, and a Self-Analysis of a Cybernetic Workstream
No full textThis dissertation curates eleven different musical projects, including three pieces of musical software and eight compositions. Each work was created between 2018 - 2024, during my time in the Music Composition PhD program at Harvard University. Much of the work presented in this portfolio is concerned with electroacoustic composition and the cybernetic relationships between performer and software instruments. More specifically, I attempt to analyze the digital instruments I have created in the past 5 years, the sound compositions I have realized using those instruments and the inherently circular feedback system of influence between software and sound. Stylistically, many of the compositions in this portfolio are densely textural and frequently imbued with dark imagery, phantasmagoria and a sense of visceral physicality. Threadline, finished in 2018/2019, initially introduces the concepts of textural density and organic growth and withdrawal of material. The compositional language originally touched upon in Threadline (2019), Cauterize (2018), and No Plume as a Trace (2019) is continually developed until the onset of the Covid-19 pandemic in January of 2020. This dramatic, global shift in lifestyle had profound effects on my compositional voice which are reflected by the works Collision Domains (2020) and To Till or Cultivate (2021).
These works are markedly less organic and are shaped by my shift towards being a more interventionist composer. Once returning back to in-person academic life at Harvard in the Fall of 2021, I felt I had rejoined society as a changed artist. I was no longer interested in composing in my prior mode of setting up a kind of musical science experiment and letting it run its course over the duration of the composition, simply observing its movements and growth. Instead, the development of material became more controlled and intentional, as reflected in my post-pandemic works red, going through pinks, to white (2022) and Grey Velvet (2024). These works, also, saw for the first time an influence of musical styles outside of Noise, New-Classical Music, and Electroacoustic Art Music. My work as a DJ at the time, fascinated by Techno, Industrial, EBM, Acid House, began to filter into my compositional work and has since remained a point of artistic influence. My ever-shifting relationships to composition, production, and performance is explored in my forthcoming album for electroacoustic viola, Ephemerist (2024), to be released on Spanish label Protomaterial Records. This dissertation then concludes by looking toward my future as a composer, musician, instrument designer and developer, and details my efforts in starting an independent record label; Idolatrous Sound Research
A Hobbit's Guide to Neurodevelopment; An Unexpected Journey into the Innate
No full textBrain development presents a remarkable case of biological self-assembly: the intricate, yet reproducible, circuitry of our mind arises from a tapestry of local cell decisions. Similar processes are ubiquitous across tissues, suggesting that distilling this complexity into simple, yet predictive models, offers valuable avenues to understand and manipulate development. Utilizing a blend of data analytics, computational simulations, and empirical studies, I explore the role of a cell's genetic makeup in shaping its synaptic connections. I first show that the genetic recognition rules governing neuronal wiring can be systematically extracted from a cell’s (1) connectivity, (2) gene expression, and (3) physical contacts (Chapters 1 and 2). Next, I illustrate how such simple neuronal recognition rules provide sufficient information to even hardwire a human brain, with additional specific results on encoding complex networks that perform competitively on ML benchmarks (Chapters 3 and 4). Finally, I show that Development, not Attention, is all you need: by raising zebrafish under anesthesia, I show that circuits underlying complex sensory behaviors can be wired up with no learning at all, simply by activity-independent developmental mechanisms (Chapter 5). In summary, by marrying network science, neurodevelopment, and artificial intelligence, I offer a fresh, quantitative lens on the enduring debate of nature versus nurture, leaning decisively towards the primacy of innate developmental processes over learned behavior
Communicating with consumers: How firms' responses to societal change influence consumer behavior
No full textOrganizations face growing pressure from their consumers and stakeholders to respond to issues of societal importance. But what happens when they do it well or do it wrong? And can such organizational responses to societal developments foster or strain consumer-firm relationships? This dissertation comprises three chapters that delve into the intricacies of communication between consumers and firms midst significant societal change.
The first chapter (Speedy Activists: How firm response time to sociopolitical events influences consumer behavior) examines how consumers take response speed as a cue to how authentic the firm when disclosing sociopolitical statements online to support an event or movement. The second chapter (Differentiating on Diversity: How Disclosing Workforce Diversity Influences Consumer Choice) examines how the public disclosure of workforce diversity data affects consumer attitudes and choice. Firms have historically avoided voluntary disclosure of what goes on in their day-to-day operations, such as workplace diversity statistics, in fear of potential consumer backlash. Contrary to this presumption, this chapter suggests that firms that voluntarily reveal their workplace diversity data do not seem to turn off consumers--even when their numbers are lackluster and revealing of racial disparities between occupations. The last chapter (Calculated Complaints: Understanding Mentions of Discrimination in Customer Service) examines how consumers react to (and sometimes, exploit) firms' attempts to meet new expectations to create inclusive environments. This work explores how consumers may strategically accuse firms of discrimination, yet such misreporting of discrimination could hinder progress for the greater cause
What’s Yours is Mine: Yale, Peru and the Ownership of Cultural Property
No full textObjects of material can be an invaluable source of information on the past, as well as a tool to help forge cultural identity. Such objects have value from aesthetic to academic, and from economic worth to political capital. There is often a lot at stake over their ownership. This is the case for many objects of pre-European Andean material. This thesis examines the dispute between Peru and Yale University over a collection of Incan material held by Yale.
At times, this dispute was quite acrimonious, with protestors marching in the streets of Lima and Cuzco, lawsuits waging in U.S. Federal Courts, and accusations and defenses sprawling across the opinion pages of The New York Times. Just as it appeared to be at a deadlock, a series of innovative agreements resolved the century-long dispute with rapidity.
This thesis explores the contested ownership and eventual resolution of the dispute over these artifacts. The particular focus is on the decisions that several key Yale personnel made that led to the return of the objects to Peru. While this cultural property dispute was covered in the media, to date no analysis has been made of why Yale chose to follow its course of action. Despite frequent portrayals by Yale as “colonial” in the popular media, a closer examination reveals that key Yale professors and administrators were internationally collaborative, working with colleagues across borders to advance scholarship and dialogue, over several decades.
The examination of the Yale-Peru dispute offers a chance to examine the specifics of what it means to curate objects and study cultures and peoples. A university, especially a research university, must reckon with the realities of geopolitics and international legal frameworks. Given the pervasiveness of cultural property disputes, the Yale-Peru example offers a unique success story, by which all parties appear to have achieved their goals. This thesis thus concludes with an examination of ways in which this case can be applied to other cultural property disputes
Development and evolution of the larval stomach of the Budgett’s Frog, Lepidobatrachus laevis
No full textAnurans have a highly conserved biphasic life history with morphologically- and ecologically- divergent tadpole and adult phases. Tadpoles are typically aquatic, filter-feeding herbivores that transform dramatically during metamorphosis into semi-terrestrial, bulk-feeding carnivores. The gut morphology of these life phases is very constrained–tadpoles have a reduced, derived stomach while adult frogs have a typical vertebrate gut with a large digestive stomach. Lepidobatrachus laevis tadpoles evolved extreme larval carnivory, even cannibalism, with nearly complete ecomorphological overlap with adult frogs. Their stomachs develop peramorphically and are adult-like at hatching. This dissertation investigates the extent of the heterochronic shift and the developmental mechanisms generating the adult-like tadpole stomach in L. laevis.
In Chapter 1, using histological examinations of microanatomy, I find that the developmental trajectory of the stomach of L. laevis is highly derived from the plesiomorphic state, and that the development of an adult stomach morphology is completely peramorphically shifted into larval development. The stomach of L. laevis does not remodel at metamorphosis. In Chapter 2, I use RNA-seq to investigate the genetic mechanisms by which development of the adult-like stomach occurs, with particular focus on the role of decreased retinoic acid in mediating this developmental shift. The findings in this chapter show that modules of stomach development in L. laevis, including those regulated by retinoic acid, are temporally shifted to resemble stomach metamorphosis in Xenopus tropicalis. The evidence presented in these two chapters provides evidence of a heterochronic shift in the development of L. laevis tadpole stomach morphology
Using genomic context to enable metabolic discovery in industrially relevant Clostridia
No full textHistorically, the bulk of microbial biochemical discoveries were made by isolating proteins or other biological macromolecules that were responsible for a phenotype of interest, whether that was a biochemical reaction, regulatory response, or ability to synthesize a molecule of interest. These approaches, while successful, were methodologically constrained by a lack of biological DNA sequencing data. With the exponential increase in sequenced microbial genomes over the past few decades, it has become clear that the vast majority of predicted genes have no known function. This sudden glut of functionally uncharacterized genes may now allow “backward” biochemical approaches to the discovery of important microbial functions that start with predicted genes.
The tendency in prokaryotes to physically co-localize sets of functionally-related genes into gene clusters within their genomes, provides an invaluable starting place for discovering new biochemical functions. This clustering provides each gene with a
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“genomic context,” loosely defined as the set of genes and regulatory elements located in, or chromosomally nearby the gene cluster in which the gene of interest occurs. Inspection of a gene of interest’s genomic context can therefore enable elucidation of its function. Theoretically, the functions of entire gene clusters can be revealed this way. Developing formal and informal approaches to exploit genomic context for to identify biochemically interesting reactions or processes would therefore greatly advance the study of microbial physiology.
After providing an overview of the significance and previous uses of genomic context analysis in Chapter 1 of this Thesis, I detail the discovery of a set of microbial gene clusters (Mlp gene clusters, or MGCs) in Chapter 2. MGCs are mostly found in bacteria, but encode close homologs of the soluble coenzyme M methyltransferases, corrinoid- dependent enzymes that participate in methanogenesis in certain methanogenic archaea. In Chapter 2, I show that the overwhelming majority of MGCs are homologous to each other, suggesting a common function, or a small set of closely related functions. Analysis of the genomic contexts of more than 300 homologous MGCs may implicate these gene clusters in methyl-selenium metabolism. I observe that a methyltransferase from the industrially-used syngas fermenter Clostridium ljungdahlii can methylate selenide using methyl-cobalamin as a methyl donor, supporting this proposed function.
While the bioinformatic and biochemical analyses in Chapter 2 implicate about 90% of MGCs in methyl-selenide metabolism, about 10% of MGCs are found in microbes with no known use for selenium in biosynthesis. I again use genomic context analysis to develop the hypothesis that these “selenium-independent” MGCs are involved in a methioninebiosynthetic pathway, most likely a methionine salvage pathway. In Chapter 3, I present evidence that the MGC from the industrial cellulose fermenter Hungateiclostridium (Clostridium) thermocellum encodes components of an unusual methionine biosynthetic pathway that uses a chemical logic distinct from known methionine biosynthetic pathways. Further, I use cell extract assays and sulfur source utilization growth studies to implicate the H. thermocellum MGC in a methionine salvage pathway rather than de novo methionine biosynthesis.
Finally, in Chapter 4, I report the chemical structures of an elusive group of cellulose- binding natural products (yellow affinity substances or flavoaffinins) produced by H. thermocellum and other cellulolytic anaerobes. Flavoaffinins have been reported in the H. thermocellum literature at least as far back as the original isolation of the organism in 1953. These natural products had previously eluded isolation and structural characterization due to instability and low yields. Isolation of two of the flavoaffinins, followed by NMR and MS-based structural elucidation revealed a unusual hydroxy-diene- g-lactone core attached to attached by a methylene bridge to an indole head-group on one side, and by a polyene chain to an aryl group on the other. I also investigate the biosynthetic origins of this unusual natural product, identify a putative flavoaffinin biosynthetic gene cluster, and formulate a biosynthetic hypothesis to explain flavoaffinin production in H. thermocellum.
In summary, the three projects detailed in this Thesis neatly illustrate various uses of genomic context analysis in studies of microbial metabolism, including exploring functionally uncharacterized gene clusters to developing testable hypotheses regarding natural product biosynthesis
The Pawn
No full textThe Pawn is a mini-series which follows our main protagonist Dunya, a 30-year- old school elementary school teacher living with her grandmother in Detroit, Michigan . Dunya’s entire life transforms after she marries a prosecuting attorney from a wealthy family. From rags to riches, housing projects to a mansion, Dunya marries into one of Detroit's wealthiest, most powerful families. Dunya’s fairytale is short lived and shortly after her one-year anniversary Dunya’s husband is murdered. Our protagonist finds herself a fly caught in a web of crime, a pawn surviving a game of death. Dunya goes from being a respected and revered teacher to the number one suspect in her husband’s homicide. Armed with nothing but her intellect and suspicions, she forms an alliance with an eclectic set of characters who help her prove her innocence and unravel a murder mystery locked deep inside the heart of the judicial system. In this Cinderella turned Sherlock Holmes story of survival and death, Dunya must prove her innocence and discover the answer to the main series question: can a pawn kill a queen and defeat the King in a real-life game of chess where every move could be her last
Children's Learning of the Compositional Number System
No full textThe compositional system of natural numbers underlies our abilities to measure time, use money,
and represent quantities. In the present dissertation, I examined how children master the
compositional number system by (i) investigating the challenges that they face in learning it and
(ii) evaluating game-based interventions to discern causal impacts of representations that facilitate
their learning. In Chapter 2, I provide evidence using home-based games that training children’s
innate numerical concepts does not support their learning of the symbolic number system taught
in school. In Chapter 3, I provide evidence using cross-linguistic comparisons that the degree of
transparency of number words in making the compositional rules of the number system explicit
(e.g., “eleven” in English that translates to “ten one” in Mandarin) affects children’s counting
skills. However, mastering the compositional number system is hard for children even when their
language’s number words reveal its logic more transparently. In Chapters 4 and 5, I provide
evidence using home-based games that training children’s understanding of the base-10
compositional number system, using multiple representations, successfully enhances their learning
of it and the numerical concepts it supports. Crucially, some games in this dissertation were
evaluated as a part of multifaceted school-based interventions that had distinct impacts on
children’s math learning. This dissertation evaluated different components of the multifaceted
interventions that could have accounted for their success. Together, this dissertation sheds light on
children’s learning of the compositional number system and highlights the importance of smallscale
home-based interventions conducted in synergy with large-scale school-based interventions
to deepen our understanding of how children learn in their real-world environments