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Cyberstalking: a new challenge for criminal law
Cyberstalking has recently emerged as a new and growing problem and is an area that will probably receive a higher profile within criminal law as more cases reach court (see Griffiths, 1999; Griffiths, Rogers and Sparrow, 1998; Bojic and McFarlane, 2002a; 2002b). For the purposes of this article we define cyberstalking as the use of information and communications technology (in particular the Internet) in order to harass individuals. Such harassment may include actions such as the transmission of offensive e-mail messages, identity theft and damage to data or equipment. Whilst a more comprehensive definition has been presented elsewhere (Bocij and McFarlane, 2002), it is hoped that the definition here is sufficient for those unfamiliar with this field. The stereotypical stalker conjures up images of someone harassing a victim who is the object of their affection. However, not all stalking incidents are motivated by unrequited love. Stalking can also be motivated by hate, a need for revenge, a need for power and/or racism. Similarly, cyberstalking can involve acts that begin with the issuing of threats and end in physical assault. We also make distinctions between conventional stalking and cyberstalking. Whilst some may view cyberstalking as an extension of conventional stalking, we believe cyberstalking should be regarded as an entirely new form of deviant behaviour
Phase diagram for the quantum Hall state in monolayer graphene
The quantum Hall state in a defect-free graphene sample is studied
within the framework of quantum Hall ferromagnetism. We perform a systematic
analysis of the pseudospin anisotropies, which arise from the valley and
sublattice asymmetric short-range electron-electron (e-e) and electron-phonon
(e-ph) interactions. The phase diagram, obtained in the presence of generic
pseudospin anisotropy and the Zeeman effect, consists of four phases
characterized by the following orders: spin-polarized ferromagnetic, canted
antiferromagnetic, charge density wave, and Kekul\'{e} distortion. We take into
account the Landau level mixing effects and show that they result in the key
renormalizations of parameters. First, the absolute values of the anisotropy
energies become greatly enhanced and can significantly exceed the Zeeman
energy. Second, the signs of the anisotropy energies due to e-e interactions
can change upon renormalization. A crucial consequence of the latter is that
the short-range e-e interactions alone could favor any state on the phase
diagram, depending on the details of interactions at the lattice scale. On the
other hand, the leading e-ph interactions always favor the Kekul\'{e}
distortion order. The possibility of inducing phase transitions by tilting the
magnetic field is discussed.Comment: 25 pages, 19 figs; v2: nearly identical to the published version,
some stylistic improvements, Tables I-IV added, anisotropy energies redefined
as u -> u/2 for aesthetic reaso
Quantum Locality?
Robert Griffiths has recently addressed, within the framework of a
'consistent quantum theory' that he has developed, the issue of whether, as is
often claimed, quantum mechanics entails a need for faster-than-light transfers
of information over long distances. He argues that the putative proofs of this
property that involve hidden variables include in their premises some
essentially classical-physics-type assumptions that are fundamentally
incompatible with the precepts of quantum physics. One cannot logically prove
properties of a system by establishing, instead, properties of a system
modified by adding properties alien to the original system. Hence Griffiths'
rejection of hidden-variable-based proofs is logically warranted. Griffiths
mentions the existence of a certain alternative proof that does not involve
hidden variables, and that uses only macroscopically described observable
properties. He notes that he had examined in his book proofs of this general
kind, and concluded that they provide no evidence for nonlocal influences. But
he did not examine the particular proof that he cites. An examination of that
particular proof by the method specified by his 'consistent quantum theory'
shows that the cited proof is valid within that restrictive version of quantum
theory. An added section responds to Griffiths' reply, which cites general
possibilities of ambiguities that make what is to be proved ill-defined, and
hence render the pertinent 'consistent framework' ill defined. But the vagaries
that he cites do not upset the proof in question, which, both by its physical
formulation and by explicit identification, specify the framework to be used.
Griffiths confirms the validity of the proof insofar as that framework is used.
The section also shows, in response to Griffiths' challenge, why a putative
proof of locality that he has described is flawed.Comment: This version adds a response to Griffiths' reply to my original. It
notes that Griffiths confirms the validity of my argument if one uses the
framework that I use. Griffiths' objection that other frameworks exist is not
germaine, because I use the unique one that satisfies the explicitly stated
conditions that the choices be macroscopic choices of experiments and
outcomes in a specified orde
Cosmological Reionization by Stellar Sources
I use cosmological simulations that incorporate a physically motivated
approximation to three-dimensional radiative transfer that recovers correct
asymptotic ionization front propagation speeds for some cosmologically relevant
density distributions transfer to investigate the process of the reionization
of the universe by ionizing radiation from proto-galaxies. Reionization
proceeds in three stages and occupies a large redshift range from z~15 until
z~5. During the first, ``pre-overlap'' stage, HII regions gradually expand into
the low density IGM, leaving behind neutral high density protrusions. During
the second, ``overlap'' stage, that occurs in about 10% of the Hubble time, HII
regions merge and the ionizing background rises by a large factor. During the
third, ``post-overlap'' stage, remaining high density regions are being
gradually ionized as the required ionizing photons are being produced.
Residual fluctuations in the ionizing background reach significant (more than
10%) levels for the Lyman-alpha forest absorption systems with column densities
above 10^14 - 10^15 cm^-2 at z=3 to 4.Comment: Revised version accepted for publication in ApJ. Color versions of
Fig. 3a-h in GIF format, full (unbinned) versions of Fig. 5, 6, and 13, as
well as MPEG animations are available at
http://casa.colorado.edu/~gnedin/GALLERY/rei_p.htm
Consistent Quantum Counterfactuals
An analysis using classical stochastic processes is used to construct a
consistent system of quantum counterfactual reasoning. When applied to a
counterfactual version of Hardy's paradox, it shows that the probabilistic
character of quantum reasoning together with the ``one framework'' rule
prevents a logical contradiction, and there is no evidence for any mysterious
nonlocal influences. Counterfactual reasoning can support a realistic
interpretation of standard quantum theory (measurements reveal what is actually
there) under appropriate circumstances.Comment: Minor modifications to make it agree with published version. Latex 8
pages, 2 figure
Economic evaluation of a nursing-led intermediate care unit
Objectives: The aim of this paper is to examine the costs of introducing a nursing-led ward program together with examining the impact this may have on patients' outcomes. Methods; The study had a sample size of 177 patients with a mean age of 77, and randomized to either a treatment group (care on a nursing-led ward, n = 97) or a control group (standard care usually on a consultant-led acute ward, n = 80). Resource use data including length of stay, tests and investigations performed, and multidisciplinary involvement in care were collected. Results: There were no significant differences in outcome between the two groups. The inpatient costs for the treatment group were significantly higher, due to the longer length of stay in this group. However, the postdischarge costs were significantly lower for the treatment group. Conclusions: The provision of nursing-led intermediate care units has been proposed as a solution to inappropriate use of acute medical wards by patients who require additional nursing rather than medical care. Whether the treatment group is ultimately cost-additive is dependent on how long reductions in postdischarge resource use are maintained
On Vector Bundles of Finite Order
We study growth of holomorphic vector bundles E over smooth affine manifolds.
We define Finsler metrics of finite order on E by estimates on the holomorphic
bisectional curvature. These estimates are very similar to the ones used by
Griffiths and Cornalba to define Hermitian metrics of finite order. We then
generalize the Vanishing Theorem of Griffiths and Cornalba to the Finsler
context. We develop a value distribution theory for holomorphic maps from the
projectivization of E to projective space. We show that the projectivization of
E can be immersed into a projective space of sufficiently large dimension via a
map of finite order.Comment: version 2 has some typos corrected; to appear in Manuscripta
Mathematic
Spin-orbit mediated anisotropic spin interaction in interacting electron systems
We investigate interactions between spins of strongly correlated electrons
subject to the spin-orbit interaction. Our main finding is that of a novel,
spin-orbit mediated anisotropic spin-spin coupling of the van der Waals type.
Unlike the standard exchange, this interaction does not require the wave
functions to overlap. We argue that this ferromagnetic interaction is important
in the Wigner crystal state where the exchange processes are severely
suppressed. We also comment on the anisotropy of the exchange between spins
mediated by the spin-orbital coupling.Comment: 4.1 pages, 1 figure; (v2) minor changes, published versio
Arithmetically Cohen-Macaulay Bundles on complete intersection varieties of sufficiently high multidegree
Recently it has been proved that any arithmetically Cohen-Macaulay (ACM)
bundle of rank two on a general, smooth hypersurface of degree at least three
and dimension at least four is a sum of line bundles. When the dimension of the
hypersurface is three, a similar result is true provided the degree of the
hypersurface is at least six. We extend these results to complete intersection
subvarieties by proving that any ACM bundle of rank two on a general, smooth
complete intersection subvariety of sufficiently high multi-degree and
dimension at least four splits. We also obtain partial results in the case of
threefolds.Comment: 15 page
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