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Love has often been regarded as merely a private affair occluded from the public domain of the political - love supposedly fostering only an expanded individualism. However, the first essential argument of this thesis is that love is already coextensive with politics - that love is an inescapable force that underpins subjectivity and as such it cannot be excluded or marginalised from discussions of the political - and since it is inescapable, we must grapple with the way it functions at level of subject formation. Therefore, this thesis's central aim is to apply a Deleuzian conceptual framework to challenge the false separation of love and politics that has been established within political theory. Through Deleuze's philosophy of difference we can understand love as process not beholden to identity, we can say that is in fact pedagogical to the degree that love must always navigate the problematic, that which does not fit in love or when love fails the event as the return of desire is fostered. Disappointment in love is central to this process for Deleuze. To radicalise love, we must also confront two central principles of identity and cyclical repetition that ground subjectivity and limit its capacity to embrace alterity: Pleasure and Memory. These subjective modes are derived from the Freudian conception of love vis-a-vi his "pleasure principle", a principle Deleuze works through and challenges, this principle ultimately rendering desire and love as dependent upon a cyclical movement of retroactivity and recollection - love becomes beholden to the return. Deleuze coupled with Freud exposes this essential tension within the core of love and the means for its overcoming. The claim that I defend in this thesis is that love may typically serve as both a conservative force subjectively and politically, but that through a Deleuzian perspective we can see that in fact love's tendency towards repetition as recollection, which is driven by lack, need not sediment identity but rather offer the means for both overcoming love as it is constituted and the means for rethinking what love can do. By applying a Deleuzian perspective we can challenge the existing image of love, which only emphasises its operation at the level of identity and unification, by a repetition of sameness which can lead to love's most violent and traumatic excesses - and we can see love as a process that not only sediments the subject but also fractures it, leading to new potentials and possibilities. Love therefore functions at a micropolitical level beyond the segmentations of molar or macropolitical negativity and conflictual identities, love being a means to undermine identity from within.

This thesis aims to develop transmission electron microscopy (TEM) techniques to study magnetic nanomaterials in three dimensions (3D). At the nanoscale, magnetic materials exhibit various intriguing behaviours such as topological protection in skyrmions (which may be used in next-generation computers), vortex states in nanorings (which are being developed to treat cancer), and long-term stability in paleomagnetic samples (which allow researchers to study the formation of planetary bodies in the solar system). Many of these behaviours are intrinsically 3D in nature, and so a 3D characterisation method is required to fully understand them. This thesis explores how magnetic imaging in the TEM can be combined with electron tomography to provide a tool for studying magnetic nanomaterials in 3D. The thesis begins by introducing the motivation, theory, and background literature relevant to magnetic electron tomography. This is then followed by a detailed study on magnetite nanorings which showcases the types of insights that can be gained through 3D magnetic imaging. Following this, it is demonstrated how prior knowledge about magnetic fields can be used to improve magnetic electron tomography experiments both through improvements to the data acquisition process as well as through changes to the data reconstruction process. At the end of the thesis, the individual strands of prior knowledge, electron tomography, and image analysis are applied independently to different projects in a section which showcases how magnetic electron tomography is intricately interconnected with the development of complementary research fields. Taken together, the content of this thesis contributes towards the maturing of magnetic electron tomography as a powerful technique for understanding magnetic nanomaterials in 3D.

Some low-mass stars appear to have larger radii than predicted by standard 1D structure models; prior work has suggested that inefficient convective heat transport, due to rotation and/or magnetism, may ultimately be responsible. In this thesis, we explore this possibility using a combination of 1D stellar models, 2D and 3D simulations, and analytical theory. First, we examine this issue using 1D stellar models constructed using the Modules for Experiments in Stellar Astrophysics (MESA) code. We begin by considering standard models that do not explicitly include rotational/magnetic effects, with convective inhibition modelled by decreasing a depth-independent mixing length theory (MLT) parameter αMLT. We provide formulae linking changes in αMLT to changes in the interior specific entropy, and hence to the stellar radius. Next, we modify the MLT formulation in MESA to mimic explicitly the influence of rotation and magnetism, using formulations suggested by Stevenson (1979) and MacDonald and Mullan (2014) respectively. We find rapid rotation in these models has a negligible impact on stellar structure, primarily because a star’s adiabat, and hence its radius, is predominantly affected by layers near the surface; convection is rapid and largely uninfluenced by rotation there. Magnetic fields, if they influenced convective transport in the manner described by MacDonald and Mullan (2014), could lead to more noticeable radius inflation. Finally, we show that these non-standard effects on stellar structure can be fabricated using a depth-dependent αMLT: a non-magnetic, non-rotating model can be produced that is virtually indistinguishable from one that explicitly parameterises rotation and/or magnetism using the two formulations above. We provide formulae linking the radially-variable αMLT to these putative MLT reformulations. We make further comparisons between MLT and simulations of convection, to establish how heat transport and stellar structure are influenced by rotation and magnetism, by looking at the entropy content of 2D local and 3D global convective calculations. Using 2D “box in a star” simulations, created using the convection code Dedalus, we investigate changes in bulk properties of the specific entropy for increasingly stratified domains. We observe regions stable against convection near the bottom boundary, resulting in the specific entropy in the bulk of the domain exceeding the bottom boundary value: this could be a result of physical effects, such as increased amounts of viscous dissipation for more supercritical, highly stratified cases, but may also be influenced by the artificial boundary conditions imposed by these local simulations. We then turn to 3D global simulations, created using the convection code Rayleigh, and investigate these same properties as a function of rotation rate. We find the average of the shell-averaged specific entropy gradient in the middle third of the domain to scale with rotation rate in a similar fashion to the scaling law derived via MLT arguments in Barker et al. (2014), i.e., |⟨ds/dr⟩| ∝ Ω^4/5.

This thesis aims to strengthen the bridge between mathematical and practical research into the transient stability of power systems. Literature that exploits the mathematical parallels between models for transient dynamics in power systems and the phenomenon of synchronisation in complex networks is explored. However, it is contended that research at the intersection of complex systems and power system stability can limit its applications to practical issues in power engineering. This thesis focuses on the measurement of transient stability in power systems in terms of a traditional stability metric for short-circuit faults on a power network, the critical clearing time (CCT). The CCT provides an upper bound on the duration of a short circuit on a power network before it is removed - cleared - by the action of protection mechanisms to isolate the faulted circuit such that the system will regain synchrony once the fault is cleared. Approaches that use energetic methods for assessing the transient stability of a power system are extended by developing metrics that can measure stability trends for different scenarios in a power system via the numerical continuation of equilibrium configurations under the variation of system parameters. An analytical CCT (ACCT) approximation is derived from this energetic framework in order to capture trends in stability with respect to a system parameter. The performance of the ACCT is compared to more accurate computations of CCT that use slower numerical simulation techniques. Attention is given to how well the ACCT approximation can capture stability trends under variation of key network design parameters such as load admittance and generator inertia. It is found for a two-machine infinite bus (TMIB) system that load parameter values that can improve stability can be identified using the ACCT. Also, the general dependence of a fault's CCT on the inertia of a generator in a TMIB power system is identifiable using the ACCT. For power systems with stationary generator inertia values, a method to provide a contingency analysis of fault locations is proposed. The method ranks the locations of short-circuit faults by their CCT; the more severe a fault the shorter its CCT. It is found in a TMIB system that the ACCT can identify the general location of severe faults under different inertia scenarios. It is shown that in larger power systems, energetic methods can be used to accurately identify the locations of faults with short CCTs. These results, together with relevant literature are used to suggest possible strategies to monitor transient stability within modern power systems.