VictorJuiz/thesis huggingface dataset:
Phase and interference phenomena in generalised probabilistic theories
Keywords: generalised probabilistic theories
theoretical physics
foundations of quantum theory
information theory
quantum physics

Phase lies at the heart of quantum physics and quantum information theory. A quantum bit is qualitatively different from a classical bit as it allows for the coherent superposition of possibilities, which demonstrate different behaviours depending on the phase between them. These behaviours constitute as interference phenomena, and lie behind the existence of algorithms in quantum computing which are arguably faster than the best classical alternatives. The concept of phase is deeply steeped in the structure of Hilbert spaces: the mathematical framework that underlies quantum theory. What if quantum theory did not hold in all scenarios, or was only a limiting case of some broader theory? In this case, would we still be able to meaningfully talk about phase and interference?
In this thesis, we will adopt an operational generalisation of quantum theory known as the framework of generalised probabilistic theories. We will provide a reasonable definition of phase in this framework. Using this, we shall explore single-particle interferometry set-ups (particularly Mach-Zehnder interferometers): experiments whose output is highly dependent on the phase between the spatially disjoint branches through which a particle might be traversing. By applying physically-motivated locality considerations, we identify the crucial role that the uncertainty principle and its generalisations play in quantum theory as an enabler of non-trivial interference. By taking into account relativity of simultaneity, we will also provide a physical motivation for why standard quantum theory provides the best description of the location of a particle traversing such a system. Finally, we apply our generalised definition of phase in the related context of particle exchange behaviour, and identify a method for classifying post-quantum particles.
All of this will demonstrate that phase between possibilities and its consequences are not uniquely quantum phenomena. Much of the behaviour we might ascribe to phase in quantum theory in fact holds generally true for phase in probabilistic theories.
Surface-electrode ion traps for scalable quantum computing
Keywords: ions
ion trappping
electrode
quantum physics

The major challenges in trapped-ion quantum computation are to scale up few-ion experiments to many qubits and to improve control techniques so that quantum logic gates can be carried out with higher fidelities. This thesis reports experimental progress in both of these areas. In the early part of the thesis we describe the fabrication of a surface-electrode ion trap, the development of the apparatus and techniques required to operate it and the successful trapping of 40Ca+ ions. Notably we developed methods to control the orientation of the principal axes and to minimise ion micromotion. We propose a repumping scheme that simplifies heating rate measurements for ions with low-lying D levels, and use it to characterise the electric field noise in the trap.
Surface-electrode traps are important because they offer a route to dense integration of electronic and optical control elements using existing microfabrication technology. We explore this scaling route by testing a series of three traps that were microfabricated at Sandia National Laboratories. Investigations of micromotion and charging of the surface by laser beams were carried out and improvements to future traps are suggested. Using one of these traps we also investigated anomalous electrical noise from the electrode surfaces and discovered that it can be reduced by cleaning with a pulsed laser. A factor of two decrease was observed; this represents the first in situ removal of this noise source, an important step towards higher gate fidelities.
In the second half of the thesis we describe the design and construction of an experiment for the purpose of replacing laser-driven multi-qubit quantum logic gates with microwave-driven ones. We investigate magnetic-field-independent hyperfine qubits in 40Ca+ as suitable qubits for this scheme. We make a design study of how best to integrate an ion trap with the microwave conductors required to implement the gate and propose a novel integrated resonant structure. The trap was fabricated and ions were successfully loaded. Single-qubit experiments show that the microwave fields above the trap are in excellent agreement with software simulations. There are good prospects for demonstrating a multi-qubit gate in the near future. We conclude by discussing the possibilities for larger-scale quantum computation by combining microfabricated traps and microwave control.
Scales of variability of atmospheric aerosols
Keywords: aerosol variability
aerosol

Aerosols have a significant effect on the global radiation budget through their interactions with radiation and clouds. However, estimates of their effect are the dominant source of uncertainty in current estimates of total anthropogenic effect on climate. A major cause of this uncertainty is the high degree of variability of aerosol properties and processes that affect their lifetime. Prediction of the aerosol effect on climate depends on the ability of three-dimensional numerical models to accurately estimate aerosol properties. However, a limitation of traditional grid-based models is their inability to resolve variability on scales smaller than a grid box. Past research has shown that significant aerosol variability exists on scales smaller than these grid-boxes, which can lead to discrepancies between observations and aerosol models.
This thesis uses a synthesis of aerosol observations, global climate model (GCM) data, and a new aerosol modelling technique implemented within a regional-scale model to quantify the important scales of aerosol variability and the extent to which different sub-grid scale processes contribute to discrepancies in aerosol modelling.
Analysis of black carbon (BC) plumes from aircraft observations shows that BC plumes represent a large portion of total BC mass and typically exist on scales of 65{ 100 km. Comparison of observed plume scales to those simulated by GCMs at multiple resolutions show that GCMs overestimate the scales of along- ight-track variability by 64% at the highest resolution. Variability is shown to be greater near sources than in remote regions, indicating that models may benefit from higher resolutions in regions of high emissions. Additionally, GCMs at all resolutions show higher variability in the latitudinal direction than the longitudinal direction, suggesting that capturing latitudinal variability may result in greater improvements in aerosol modelling.
This work additionally presents a novel technique to allow one to isolate the effect of aerosol variability from other sources of variability within the model. Processes most affected by neglecting aerosol sub-grid variability are gas-phase chemistry and aerosol uptake of water through the aerosol/gas equilibrium reactions. The inherent non-linearities in these processes result in large changes in aerosol parameters when aerosol and gaseous species are artificially mixed over large spatial scales. These changes in aerosol and gas concentrations are exaggerated by convective transport, which transports these altered concentrations to altitudes where their effect is more pronounced. Future aerosol model development should focus on accounting for the effect of sub-grid variability on these processes at global scales in order to improve model predictions of the aerosol effect on climate.
“Missionary zeal of recent converts”: norms and norm entrepreneurs in the foreign policy of the Czech Republic, Poland and Slovakia 1989-2011
Keywords: norms
transition
Central Europe
Foreign policy
norm entrepreneurs

The following dissertation discusses the role of norms and norm entrepreneurs in the foreign policy-making of the Czech Republic, Poland and Bratislava after the downfall of communism. In at attempt to unpack the mechanics and appliance of “soft power” in foreign policy practice in post-communist Central and Eastern Europe, it identifies conditions and analyzes processes via which norms come to play the role of intermediary variable in the articulation and enactment of national interest. Capitalizing on the agency-oriented strand of norm diffusion theory in international relations and discursive institutionalism scholarship in comparative politics, the dissertation argues that normative frameworks advocated by value-bound networks of so-called norm entrepreneurs can play a regulative function in foreign policy-making by setting boundaries for discourse and sustaining logics of appropriateness that constrain the pool of available foreign policy choices at critical junctures.
In the first part, “the mission and conversion” (1989-1999), the dissertation focuses on the early stages of norm emergence and habituation in the three states in the 1990s, asserting that ideational influence incurred by American “missionaries” on Czech, Polish and Slovak “converts” to democracy via a range of socialization processes related to NATO enlargement and Western democracy promotion efforts in the region gave rise to norm entrepreneur groups bound by a shared commitment to a normative framework dubbed “dissident geopolitics”.
In part two, “the zeal”, the dissertation concentrates on the later stages of norm internalisation, demonstrated by norm enforcement in foreign policy. Using case studies of Czech, Polish and Slovak foreign policy during the Iraq War (2002-2003), the Orange Revolution in Ukraine (2004-2005) and the Russia Reset (2009-2011), the dissertation shows how sustained advocacy by norm entrepreneurs with or without structural power, who skillfully use framing to push their normative agendas in discursive competition with other norm entrepreneurs, factors “dissident geopolitics” in the decision-making process that produces activist and value-laden foreign policy outcomes that might not have been expected of “weak” states. Ultimately, the dissertation argues that dominant norms and norm entrepreneur networks can thrive in transition settings when they are less disputed, but they tend to lose coherence and unity, respectively, as the foreign policy landscape diversifies upon completion of democratic consolidation.
Spaces of trust and mistrust : Congolese refugees, institutions and protection in Kampala, Uganda
Keywords: space
trust
communities
protection
institutions
Urban refugees

The spatiality of refugee protection has been a key issue for humanitarian practitioners and policy-makers, and it has become of increasing concern in academic studies. This study interrogates the policy and practice-oriented concept of ‘protection space’ in regard to the experiences of the Congolese refugees in the city of Kampala, Uganda. My analysis of ‘protection space’ uses the geographical concepts of the ‘right to the city’ and ‘sense of place’ to emphasise the physical, imagined, lived and relational understandings of urban space. I also investigate the conceptual links between ‘protection’, ‘space’ and ‘trust’. I apply a qualitative case-study approach in this study and collected primary data from individual Congolese refugees, refugee communities and officers of the protection institutions. The data-collection methods included a combination of semi-structured interviews, observation and focus group discussions, supported by visual methods. I rely on aspects of discourse analysis to analyse my textual and visual data.
I conclude that the Congolese refugees informing this study conceptualised ‘protection’ not only legally, physically and relationally, but also spiritually. The geographical levels of protection and insecurity that refugees experienced varied: their ‘sense of place’ in relation to the city of exile depended on their micro-, meso-, and macro-scale experiences and perceptions of protection. Given the prevalence of generalised and particularised social mistrust and institutional mistrust – two matters that were intertwined in refugees’ discourses of their everyday urban life – it is concluded that the distinction between protection and insecurity was at times unclear. Refugees, however, found a sense of protection from various ‘communities of trust’, even though their community life was also characterised by struggles over their ‘right to the city’ and inter-community mistrust.
InSAR measurements of volcano deformation on the Central American Volcanic Arc
Keywords: satellite remote sensing
volcano

Satellite measurements of volcano deformation have the potential to illuminate a wide range of volcanic processes and have provided us with the first opportunity to investigate volcano deformation as an arc-scale process. This thesis presents the results of an Interferometric Synthetic Aperture Radar (InSAR) survey of the Central American Volcanic Arc between 2007 and 2010. My measurements confirm a statistically significant absence of magmatic deformation in Central America relative to other well-studied volcanic arcs. I estimate a minimum detection threshold for deformation at 20 of the arc’s 26 active volcanoes using time series analysis of interferometric phase. I find that the majority (∼80%) of literature measurements of volcano deformation made at other arcs would have been possible with the average magnitude of noise in Central American volcanoes. The absence of measurable magmatic deformation in Central America may therefore be due to factors that limit the geodetic expression of magma movement, including the deep pooling of basalts and high parental melt volatile content. The quantification of measurement uncertainty also allows me to use the lack of deformation at specific erupting volcanoes to make order of magnitude estimations of the minimum depth for magma storage that would not result in measurable deformation. I present measurements and interpretation of non-magmatic deformation associated with edifice development at two Central American volcanoes: Arenal, Costa Rica and Santiaguito, Guatemala. At Arenal, I measure apparently steady slip (∼7 cm/yr) on the volcano’s western flanks, which I attribute to gravity-driven slip on the boundary between lavas emplaced over the past 50 years and older tephras and paleosols. At Santiaguito, I demonstrate the measurement of large-scale (∼10-200 m) topographic change from a small set of large baseline interferograms. Measurements of post-2000 lava fields allow me to estimate extrusion rate, map changes to flow morphology and make simultaneous measurements of lava flow thickness and subsidence rate.
Carbon cycling in a Bornean tropical forest 
Keywords: above- and below-ground biomass
net primary productivity
soil respiration
Carbon cycling
Borneo
tropical forest

The tropical forests on the island of Borneo are among of the richest in the world in terms of tree diversity, and their capacity to store a large reservoir of carbon. The Southeast Asian forests are fundamentally different from Neotropical and African forests, with their single-family dominance by dipterocarp trees, and with inherently greater stature and biomass. The carbon productivity and allocation in Asian tropical forests is still poorly quantified, and their responses to environmental drivers are still poorly understood. Almost all recent advances in tropical forest carbon cycling research have occurred in the Neotropics, with very few studies in Asia. The principal aim of this thesis is to quantify the carbon budget of a lowland dipterocarp forest in the Lambir Hills National Park, Miri, Sarawak, Malaysian Borneo. I examined and explored the productivity and carbon cycling processes and their responses to environmental factors across two major and contrasting soil types, in particular the clay and sandy loam soils. I recorded and analysed the Net Primary Productivity (NPP) and respiration for the above- and below-ground components, and observed the responses to seasonal variation and environmental drivers.
Total soil respiration was relatively high and contributed a great deal to ecosystem respiration. Variation in soil respiration rates appeared closely related to soil moisture content. I found a strong diurnal cycle in soil respiration. On the basis of the first soil carbon dioxide (CO2) efflux partitioning study undertaken in a tropical forest, the diurnal cycle in total soil respiration appeared to be entirely driven by the diurnal cycle in litter respiration, and in turn litter is strongly controlled by moisture.
There was little seasonal variation in allocation of net primary productivity (NPP), but there was evidence showing potential inter-annual variability for several components of NPP. Further, the allocation of NPP showed a strong seasonal shift between the forest plots on clay and sandy loam soils. Combining all the data measured and obtained in this D.Phil. thesis, the overall carbon budget assessed in this lowland dipterocarp forest showed a high level of agreement with other studies in Asia using micrometeorological techniques and the situation appears to be comparable to tropical forests in Amazonia. The key difference is that the aboveground NPP is higher and is the largest component contributing to the overall carbon budget, with relatively higher carbon use efficiency (CUE). The lowland dipterocarp forest in Lambir shows higher allocation in the above-ground NPP, and there were also differences in NPP and its allocation between sandy and clay-rich plots.
'Irish by descent': Marianne Moore, Irish writers and the American-Irish Inheritance'
Keywords: American modernism
culture and politics
Irish literature
Marianne Moore
modernist poetry
transatlantic identities
syllabic poetry

Despite having a rather weak family connection to Ireland, the American modernist poet Marianne Moore (1887-1972) described herself in a letter to Ezra Pound in 1919 as ‘Irish by descent’. This thesis relates Moore’s claim of Irish descent to her career as a publisher, poet and playwright, and argues that her decision to shape an Irish inheritance for herself was linked with her self-identification as an American poet. Chapter 1 discusses Moore’s self-confessed susceptibility to ‘Irish magic’ in relation to the increase in contributions from Irish writers during her editorship of The Dial magazine from 1925 to 1929. Moore’s 1915 poems to the Irish writers George Moore, W. B. Yeats and George Bernard Shaw, which reveal a paradoxical desire for affiliation to, and disassociation from, Irish literary traditions, are scrutinized in Chapter 2. Chapters 3a and b discuss Moore’s ‘Irish’ poems ‘Sojourn in the Whale’ (1917) and ‘Spenser’s Ireland’ (1941). In both poems political events in Ireland – the ‘Easter Rising’ of 1916 and Ireland’s policy of neutrality during World War II – become a backdrop for Moore’s personal anxieties as an American poet of ‘Irish’ descent coming to terms with her political and cultural inheritance. Expanding upon previous chapters’ discussion of the interrelation of poetics and politics, Chapter 4 shows how Moore’s use of Irish sources in ‘Spenser’s Ireland’ and other poems including ‘Silence’ and the ‘Student’ reflects her quixotic attitude to Irish culture as alternately an inspiration and a tool for manipulation. The final chapter discusses Moore’s adaptation of the Anglo-Irish novelist Maria Edgeworth’s 1812 novel The Absentee as a play in 1954. Through this last piece of ‘Irish’ writing, Moore adopts a sentimentality that befits the later stages of her career and illustrates how Irish literature, rather than Irish politics, has emerged as her ultimate source of inspiration.
Templated interlocked host structures for the recognition and sensing of charged substrates
Keywords: rotaxane
anion
sensing
catenane

This thesis describes the synthesis of acyclic, macrocyclic and, in particular, interlocked anion and ion-pair receptors and sensors.
Chapter One will introduce the field of supramolecular chemistry with particular emphasis on areas which are pertinent to this thesis, including anion receptor design and templated synthesis of interlocked structures.
Chapter Two focuses on the synthesis of new heteroditopic macrocycles functionalised with both cation and anion recognition sites and their incorporation into interlocked architectures. The affinity for a range of anions and ion-pairs is explored via 1H NMR and UV-visible spectroscopy as well as by X-ray crystallography.
Chapter Three details the incorporation of d- and f-metal luminescent reporter groups into an isophthalamide motif in order to construct acyclic, macrocyclic and [2]rotaxane receptors.
Chapter Four investigates the synthesis of complex higher-order interlocked structures through post-synthetic modification of lower-order interlocked structures.
Chapter Five explores the potential for fluorescent gold nanoparticle conjugates to act as luminescent and colourimetric sensors for chemical warfare agents (CWAs) by employing a fluorescent displacement assay technique.
A marine geophysical study of the Wilkes Land rifted continental margin, Antarctica
Keywords: sedimentology
Antarctica
flexure
subsidence
Wilkes Land
geophysics

The Wilkes Land margin of East Antarctica, conjugate to the southern Australian margin, is a non-volcanic rifted margin that formed during the Late Cretaceous. During 2000-01 and 2001-02, Geoscience Australia (GA) acquired ~10,000 line km of seismic reflection, magnetic anomaly, and gravity anomaly data, on the Wilkes Land margin. Seismic reflection and sonobuoy refraction data provide the first constraints on sediment thickness and images of the deep crustal structure for the extent of the Wilkes Land margin. Two major post-rift seismic-stratigraphic sequences are recognised, separated by a regionally correlatable unconformity. The unconformity is interpreted as Early- to Middle-Eocene (~50 Ma). This unconformity has previously been interpreted to represent the onset of continent-wide glaciation at ~34 Ma. A major unconformity at the base of post-rift sediments is interpreted as a breakup unconformity, of approximately Turonian (85-90 Ma) age. Timing the onset of seafloor spreading using lineated magnetic anomalies within the Australia-Antarctic Basin (AAB) is extremely difficult due to uncertainties in correlating anomalies to the geomagnetic reversal time scale. Modelling indicates that the anomaly commonly correlated to Chron 34y may, in some cases, be associated with high level intrusions and/or serpentinisation of exhumed upper-mantle peridotites. Process-oriented gravity modelling indicates that the Wilkes Land margin lithosphere is characterised by a relatively high effective elastic thickness (Te). Isostatic anomalies are most effectively reduced for models utilising Te = 30 km. Although the margin is broadly characterised by a high Te, zones of low Te are inferred from modelling. Spectral analysis of isostatic anomalies indicates that the power of the flexural isostatic anomalies is lower than the free air gravity anomalies. The margin does not appear to be segmented, at least in regard to its long-term strength. However, a change in initial, zero-elevation crustal thickness (Tc) is inferred from west to east. A Tc of ~35 km is inferred for western Wilkes Land, whereas eastern Wilkes Land is characterised by Tc = 29 to 31 km. Limited seismic refraction data from the conjugate margin indicates a similar trend from southwest to southeast Australia.