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The current neutrino detectors have been able to detect neutrinos in the range of TeV to 100 PeV, however, ultra high energy (UHE) neutrinos above 100 PeV still remain to be detected. A new neutrino detector, the RNO-G, is currently being constructed in Greenland with the purpose of detecting the first UHE neutrinos using radio antennas capable of measuring the Askaryan pulse generated after a neutrino interaction with the ice molecules. To reconstruct the neutrino's properties from the antennas' output deep learning models have been used previously. In this work we present a Graph Neural Network capable of reconstructing the shower energy and neutrino direction with similar performance compared to Convolutional Neural Networks used in previous works, using a fraction of the training data. Additionally, an increase of the reconstruction performance is shown when using the full data set.

In an attempt to check published results on diffusion effects in M67 a non-LTE analysis is made on 28 high resolution FLAMES-UVES spectra of dwarfs and sub-giants around the turnoff point, where core hydrogen fusion halts. This analysis utilizes the software-suites LOTUS and iSpec to determine stellar parameters from equivalent-width measurements. With larger parameter scatter than expected diffusion effects were difficult to pin down. Eight spectra from either known variable stars (Kepler K2 data) or having low signal-to-noise data were therefore removed. This new reduced dataset confirms \citet{diffusionm672} that non-LTE analyses reduces scatter and makes diffusion trends easier to identify. This may however also be the result of systematic errors in LOTUS and requires more (and independent) confirmation. / För att undersöka publicerade diffusionseffekter i M67 genomförs en analys utan LTE av 28 högupplösta FLAMES-UVES spektra av dvärgar och subjättar runt turnoffpunkten. Med programmen LOTUS NLTE och iSpec bestämdes atmosfäriska parametrar från uppmätta linjestyrkor. Initialt fanns det en stor spridning i de erhållna paramternarna, vilket gjorde det svårt att dra slutsatser om diffusion. Åtta spektra från antingen kända variabler (Kepler K2-data) eller med låg signal till brus togs därför bort. Detta nya reducerade dataset verkar bekräfta \citet{diffusionm672} att icke-LTE minskar spridning och gör diffusionstrender mer lättidentifierade. Resultatet kan dock vara ett resultat av systematiska fel i LOTUS och behöver därmed ytterliggare bekräftas.

Environment plays an important role in the evolution of galaxies. In particular, denser environments, such as galaxy clusters and large-scale field filaments of the cosmic web have been found to reduce star formation in galaxies. The intersection of these environments provides an interesting regime of study. We investigate how cosmic filaments impact the quenching of galaxies within one virial radius of 324 simulated clusters. We use hydrodynamic runs from The Three Hundred Project along with the cosmic web extractor DisPerSE to track filaments and the structure finder VELOCIraptor to identify halos hosting galaxies. Limited by the resolution of the simulation, we examine star formation indirectly by way of galaxy colour and cold gas fraction. We find that cluster galaxies residing closer to filaments tend to be star-forming, bluer, and contain more cold gas than their counterparts further away from filaments. This is in stark contrast with galaxies residing outside of clusters, where galaxies close to filaments show clear signs of density related pre-processing. Careful examination of flows around and into cluster galaxies strongly suggests that the colder, dynamically coherent hydrodynamic streams along intra-cluster filaments partially shield galaxies close to them from strangulation by the hot, dense intra-cluster medium. These streams, in addition to the reduced density contrast of intra-cluster filaments with the intra-cluster medium, also limit the ram pressure stripping experienced by cluster galaxies. We further examine stripping in the context of gas disturbances in phase space to create a classification for wet and dry galaxies. / Thesis / Master of Science (MSc)

To reconstruct the history of the Milky Way, the chemo-physical characterization of stars is essential. For this, the chemical abundances of the Gaia Data Release 3 spectroscopy are of special importance, as they can be combined with dynamical properties in a chemo-kinematical analysis to find the relations between the chemistry and the Milky Way structure. This project explores nine abundance ratios in the DR3 and their evolution with the metallicity, distance to the galactic plane, azimuthal velocity, and eccentricity of the orbits of the stars.

The gradual blending of classical science and epistemology with indigenous/traditional practices and modes of understanding (particularly magic and religion) in the early western Middle Ages tends to be misunderstood. The purpose of this study is to address the reason(s) why the early medieval West has been labeled an irrational, unscientific "Dark Age" in order to point out that this conception's existence has more to do with limited historical perspectives than with reality. The anachronistic superimposition of modern presuppositions and methodological expectations is a very old phenomenon. Ironically, however, it has crept into the history of science and extended to ostensibly objective "scientific" historiography to such a degree that dismissiveness regarding the other ways of knowing that have informed our scientific and epistemological development frequently tends to obscure historical continuity. My goal in this undertaking is to firmly establish how we may understand that the intellectual revolution beginning in twelfth-century Europe was founded on a rich and multifarious tradition of knowledge and understanding; the preceding seven or eight centuries of the early Middle Ages was not one of intellectual "darkness" and should not be discarded as such. The approach I have taken is intended to demonstrate, rather than simply state, this goal by roughly imitating of the process of intellectual transmission in the early Middle Ages. Therefore, primary sources are supplemented by numerous secondary interpretations from various academic disciplines in the hope that collecting and reforming ideas in this fashion will draw out the inherent connectivity of ideological thought structures and approaches to the natural world. / Master of Arts

The following thesis project explores the design of a nature center and planetarium within Rock Creek Park, in Washington, DC. The project evolved from a desire to re-imagine a relationship with nature in a way that allows conversation, reflective thinking, and allows one's sense of wonder to enter a place which is between science and myth. The design of the nature center and planetarium was developed by investigating the dualities which exist within and around the site, such as earth and air, day and night,and winter and summer. The goal was to create a building which is fully embedded in the site around it, to create a unique environment for exploration and conversation, and a place to contemplate one's relationship with nature. / Master of Architecture

Comprehending star formation in nearby galaxies is essential for deciphering the core mechanisms behind stellar birth. Using high-resolution CO line emission data from the Atacama Large Millimeter/submillimeter Array (ALMA), this research examines the CO excitation characteristics in two nearby star-forming galaxies, NGC 2903 and NGC 3627. We processed raw data cubes with pystructure, creating 2D moment maps to visualize CO ratios. High-resolution CO data from different rotational transitions (CO(1-0), CO(2-1), CO(3-2)) were used to study CO excitation. The study also incorporated stellar mass surface density and star formation rate (SFR) surface density maps to explore correlations between these properties and CO ratios. Using the Dense Gas Toolbox, we outlined the density structures of molecular gas, offering deeper insights into the underlying physical conditions influencing observed CO excitation patterns. We detected changes in CO line ratios that emphasize areas with elevated excitation conditions, suggesting higher gas density or temperature, which are closely associated with star formation activities. These variations suggest that non-thermal processes, such as collisions and radiation from stars, significantly influence CO excitation, as evidenced by the non-local thermodynamic equilibrium (non-LTE) excitation observed. Our findings indicate that the CO(3-2)-to-lower-J ratios are significantly affected by the SFR surface density, underscoring the influence of local star-forming environments on molecular gas excitation. Moment ratio maps display higher CO(3-2)/CO(2-1) ratios in the central regions of both galaxies, implying increased radiation and elevated temperatures in these zones. The connection between elevated CO ratios and regions with high SFR surface density further supports this relationship.x In contrast, stellar mass surface density appears to have a less pronounced effect on CO excitation, suggesting that local star formation processes, rather than large-scale galactic structures, predominantly drive the excitation conditions. This study highlights the importance of CO line ratios as diagnostic tools for understanding the excitation conditions of molecular gas in star-forming galaxies.

This project consists on the characterisation of the atmosphere of the exoplanet Wasp-107b, by observing the existence (or absence) of 4 different molecules: H20, CO2, CO and CH4.  To achieve this we use 2 algorithms:  - SYSREM, which eliminates the undesired stellar and thelluric features. -Cross-correlation, which compares the planetary spectrum with the molecules one. After applying these algorithms to 3 sets of simulations we can tell what mollecules are present in the planet's atmosphere.

This thesis deals with the relation of Hellenic philosophy to evolutionary biology. The first part entails an explication of Hellenic cosmology and metaphysics in its traditional understanding, as the Western component of classical Indo-European philosophy. It includes an overview of the relevant contributions by the Presocratics, Plato, Aristotle, and the Neoplatonists, focusing on the structure and origin of both the intelligible and sensible worlds. Salient aspects thereof are the movement from the transcendent Principle into the realm of Manifestation by means of the interaction between Essence and Substance; the role of the Logos, being the equivalent of Plato’s Demiurge and Aristotle’s Prime Mover, in the cosmogonic process; the interaction between Intellect and Necessity in the formation of the cosmos; the various kinds of causality contributing to the establishment of physical reality; and the priority of being over becoming, which in the case of living organisms entails the primacy of soul over body. The first part of the thesis concludes with a discussion of the implications of Hellenic cosmology and metaphysics for evolutionary biology, including an affirmation of final and formal causality over and against its rejection by the modern scientific project. The second part commences with a delineation of organic form and transformation, emphasizing the mathematical foundations thereof. It continues with a critical consideration of the modern evolutionary theory on both scientific and philosophical grounds. In the process a fundamental distinction is made between micro- and macro-evolution, involving the reshuffling of existing genetic material which is acted upon by natural selection, and the production of new genetic material by means of macro-mutations, respectively. In the remainder of the thesis the macro-evolutionary process is described as mainly lawful, directed and convergent, instead of contingent, undirected and divergent as postulated in the modern evolutionary synthesis. This approach does not preclude the recognition of exceptions, due to the limitation of Intellect by Necessity – that is to say, of teleology by mechanism. / Religious Studies & Arabic / D.Litt. et Phil. (Religious Studies)