550 research outputs found
Plasmon signatures in high harmonic generation
High harmonic generation in polarizable multi-electron systems is
investigated in the framework of multi-configuration time-dependent
Hartree-Fock. The harmonic spectra exhibit two cut offs. The first cut off is
in agreement with the well established, single active electron cut off law. The
second cut off presents a signature of multi-electron dynamics. The strong
laser field excites non-linear plasmon oscillations. Electrons that are ionized
from one of the multi-plasmon states and recombine to the ground state gain
additional energy, thereby creating the second plateau.Comment: Major revision, 12 pages, 5 figures, submitted to J. Phys. B (2005),
accepte
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Antihumanism in queer theory
Although queer theory is distinguished by its antihumanistic rhetoric, in much of queer theory antihumanism is more about performance than substance. This is not a bad thing, for, on those occasions when queer theory takes its antihumanism too seriously, it commits itself to incoherence. I illustrate this through an intertextual critique of Edelman's and Bersani's works. Edelman's celebration of the death drive is internally torn between an amoral standpoint and immoral urges. Unlike recent critical interventions, however, my point is less to impugn queer theory's preoccupation with antinormativity, than the performance of antinormativity that manifests as queer antihumanism
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The foundations of the rule of law
Formal conceptions of the rule of law are popular among contemporary legal philosophers. Nonetheless, the coherence of accounts of the rule of law committed to these conceptions is sometimes fractured by elements harkening back to substantive conceptions of the rule of law. I suggest that this may be because at its origins the ideal of the rule of law was substantive through and through. I also argue that those origins are older than is generally supposed. Most authors tend to trace the ideas of the rule of law and natural law back to classical Greece, but I show that they are already recognisable and intertwined as far back as Homer. Because the founding moment of the tradition of western intellectual reflection on the rule of law placed concerns about substantive justice at the centre of the rule of law ideal, it may be hard for this ideal to entirely shrug off its substantive content. It may be undesirable, too, given the rhetorical power of appeals to the rule of law. The rule of law means something quite radical in Homer; this meaning may provide a source of normative inspiration for contemporary reflections about the rule of law
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Why rights are not optimisation requirements
In this article I pursue the implications of the statement that constitutional rights are – as Alexy’s principles theory argues – optimisation requirements, and show that they are not. I argue that, applied to moral rights, optimisation obfuscates their nature, their relationship to human well-being, and the work they do in practical thought. As to constitutional rights, I argue that the fact that they belong in an institutional framework suggests some reasons for treating them like optimisation requirements in circumscribed cases. But these reasons are far from conclusive; and treating rights like optimisation requirements in other scenarios (conflicts of rights, structural discretion) indicates that optimisation, as defined in the principles theory, does not assist us in thinking well about the structure of constitutional rights. Constitutional rights demand compliance with whatever the interests on which they are based demand – whether or not what they demand is antecedently clear – not with some purported optimisation requirement
Phase Space Approach to Laser-driven Electronic Wavepacket Propagation
We propose a phase space method to propagate a quantum wavepacket driven by a
strong external field. The method employs the so-called biorthogonal von
Neumann basis recently introduced for the calculation of the energy eigenstates
of time-independent quantum systems [A. Shimshovitz and D.J. Tannor,
arXiv:1201.2299v1]. While the individual elements in this basis set are
time-independent, a small subset is chosen in a time-dependent manner to adapt
to the evolution of the wavepacket in phase space. We demonstrate the accuracy
and efficiency of the present propagation method by calculating the electronic
wavepacket in a one-dimensional soft-core atom interacting with a superposition
of an intense, few-cycle, near-infrared laser pulse and an attosecond
extreme-ultraviolet laser pulse.Comment: 4 pages, 4 figures. The following article has been submitted to the
Journal of Chemical Physics. After it is published, it will be found at
http://jcp.aip.org
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Philosophical problems with the gender critical feminist argument against trans inclusion
The Reform of the Gender Recognition Act: Government Consultation (2018) catalyzed a heated debate on transgender rights and trans inclusion in the United Kingdom. I start by explaining what the reforms to the U.K. system of gender recognition propose, why gender-critical feminists oppose them, and how other feminist academics have responded to their arguments. I then offer a more detailed philosophical critique of gender-critical trans-exclusionary feminist arguments. I argue that the gender-critical feminist case against trans women’s access to women-only (or sex-segregated, or single-sex) spaces suffers from a number of fallacies, and introduces modes of argument that are at odds with well-established and sound uses of practical reason. I try to make sense of these problems with gender-critical feminist thought by appealing to the idea of presupposed paranoid structuralism. I also argue that gender-critical feminists’ enthusiastic use of social media and allied online platforms may be implicated in generating some of these problems
Correlated non-perturbative electron dynamics with quantum trajectories
An approach to electron correlation effects in atoms that uses quantum
trajectories is presented. A comparison with the exact quantum mechanical
results for 1D Helium atom shows that the major features of the correlated
ground state distribution and of the strong field ionization dynamics are
reproduced with quantum trajectories. The intra-atomic resonant transitions are
described accurately by a trajectory ensemble. The present approach reduces
significantly the computational time and it can be used for both bound and
ionizing electrons.Comment: 9 pages, 4 figure
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Graceful remedies: understanding grace in the Catholic Church's treatment of clerical child sexual abuse
This article examines advocacy of Catholic restorative justice for clerical child sexual abuse from the standpoint of feminist criminological critiques of the use of restorative mediation in sexual offence cases. In particular, it questions the Catholic invocation of grace and forgiveness of survivors of abuse in light of critical feminist concerns about the exploitation of emotions in restorative practices, especially in regard to sexual and other gender-based offences. In the context of sexual abuse, the Catholic appeal to grace has the potential for turning into an extraordinary demand made of victims not only to rehabilitate offenders and the church in the eyes of the community, but also to work towards the spiritual absolution of the abuser. This unique feature of Catholic-oriented restorative justice raises important concerns in terms of feminist critiques of the risk of abuses of power within mediation, and is also incompatible with orthodox restorative justice theory, which, although it advocates a ‘spiritual’ response to crime, is concerned foremost with the rights, needs and experiences of victims
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