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The Adjudication and Enforcement of Rights After Brexit
This report records the inaugural meeting and roundtable of the Brexit and Rights Engagement Network (BREN) on Tuesday 3rd July 2018 at Edinburgh Law School. Attendees at the roundtable included network members, fellow academics, representatives of the Scottish Parliament, the Scottish Government, the Scottish Human Rights Commission, the Equality and Human Rights Commission, the legal professions, and NGOs. Two years after the EU Referendum and only a few days after the European Union (Withdrawal) Act 2018 (the 2018 Act) receiving Royal Assent, the Brexit and Rights Engagement Network met for the first time. The purpose of the roundtable was to ignite debate amongst legal scholars and policy makers, and others working in a rights environment relating to interpretation, adjudication and enforcement of rights in the lead up to, and following “Brexit Day,” (March 29, 2019). This report is split into two sections, Part A will consider the adjudication of EU rights, but also their enforcement under the 2018 Act and the Withdrawal Agreement, whilst ‘options for the future’ will be broached in Part B
Opening the Rome-Southampton window for operator mixing matrices
We show that the running of operators which mix under renormalization can be
computed fully non-perturbatively as a product of continuum step scaling
matrices. These step scaling matrices are obtained by taking the "ratio" of Z
matrices computed at different energies in an RI-MOM type scheme for which
twisted boundary conditions are an essential ingredient. Our method allows us
to relax the bounds of the Rome-Southampton window. We also explain why such a
method is important in view of the light quark physics program of the RBC-UKQCD
collaborations. To illustrate our method, using n_f=2+1 domain-wall fermions,
we compute the non-perturbative running matrix of four-quark operators needed
in K->pipi decay and neutral kaon mixing. Our results are then compared to
perturbation theory.Comment: 8 pages, 7 figures. v2: PRD version, minor changes and few references
adde
The kaon semileptonic form factor in Nf=2+1 domain wall lattice QCD with physical light quark masses
We present the first calculation of the kaon semileptonic form factor with
sea and valence quark masses tuned to their physical values in the continuum
limit of 2+1 flavour domain wall lattice QCD. We analyse a comprehensive set of
simulations at the phenomenologically convenient point of zero momentum
transfer in large physical volumes and for two different values of the lattice
spacing. Our prediction for the form factor is f+(0)=0.9685(34)(14) where the
first error is statistical and the second error systematic. This result can be
combined with experimental measurements of K->pi decays for a determination of
the CKM-matrix element for which we predict |Vus|=0.2233(5)(9) where the first
error is from experiment and the second error from the lattice computation.Comment: 21 pages, 7 figures, 6 table
QSO clustering and the AAT 2dF redshift survey
We review previous results on the clustering and environments of QSOs. We
show that the correlation length for QSOs derived from existing surveys is
r~5/h Mpc, similar to the observed correlation length for field galaxies at the
present epoch. The galaxy environment for z<1 radio-quiet QSOs is also
consistent with field galaxies. The evolution of the QSO correlation length
with redshift is currently uncertain, largely due to the small numbers of QSOs
(~2000) in surveys suitable for clustering analysis. We report on intial
progress with the AAT 2dF QSO redshift survey, which, once completed will
comprise almost 30000 QSOs. With over 1000 QSOs already observed, it is already
the largest single homogeneous QSO survey. We discuss prospects for deriving
limits on cosmological parameters from this survey, and on the evolution of
large-scale structure in the Universe.Comment: Invited talk at RS meeting on 'Large Scale Structure in the Universe'
held at the Royal Society on 25-26 March 1998 14 pages, 11 figre
Lattice determination of the Decay Amplitude
We describe the computation of the amplitude A_2 for a kaon to decay into two
pions with isospin I=2. The results presented in the letter Phys.Rev.Lett. 108
(2012) 141601 from an analysis of 63 gluon configurations are updated to 146
configurations giving Re GeV and Im
GeV. Re is in good agreement with the experimental result, whereas the
value of Im was hitherto unknown. We are also working towards a direct
computation of the amplitude but, within the
standard model, our result for Im can be combined with the experimental
results for Re, Re and to give
ImRe . Our result for Im\, implies
that the electroweak penguin (EWP) contribution to
is Re.Comment: 59 pages, 11 figure
A Morphological and Multicolor Survey for Faint QSOs in the Groth-Westphal Strip
Quasars representative of the populous faint end of the luminosity function
are frustratingly dim with m~24 at intermediate redshift; moreover groundbased
surveys for such faint QSOs suffer substantial morphological contamination by
compact galaxies having similar colors. In order to establish a more reliable
ultrafaint QSO sample, we used the APO 3.5-m telescope to take deep groundbased
U-band CCD images in fields previously imaged in V,I with WFPC2/HST. Our
approach hence combines multicolor photometry with the 0.1" spatial resolution
of HST, to establish a morphological and multicolor survey for QSOs extending
about 2 magnitudes fainter than most extant groundbased surveys. We present
results for the "Groth-Westphal Strip", in which we identify 10 high likelihood
UV-excess candidates having stellar or stellar-nucleus+galaxy morphology in
WFPC2. For m(606)<24.0 (roughly B<24.5) the surface density of such QSO
candidates is 420 (+180,-130) per square degree, or a surface density of 290
(+160,-110) per square degree with an additional V-I cut that may further
exclude compact emission line galaxies. Even pending confirming spectroscopy,
the observed surface density of QSO candidates is already low enough to yield
interesting comparisons: our measures agree extremely well with the predictions
of several recent luminosity function models.Comment: 29 pages including 6 tables and 7 figures. As accepted for
publication in The Astronomical Journal (minor revisions
Standard-model prediction for direct CP violation in decay
We report the first lattice QCD calculation of the complex kaon decay
amplitude with physical kinematics, using a lattice
volume and a single lattice spacing , with GeV. We find
Re GeV and Im GeV, where the first error is statistical
and the second systematic. The first value is in approximate agreement with the
experimental result: Re GeV while the second
can be used to compute the direct CP violating ratio
Re, which is
below the experimental value . The real
part of is CP conserving and serves as a test of our method while the
result for Re provides a new test of the
standard-model theory of CP violation, one which can be made more accurate with
increasing computer capability.Comment: 9 pages, 3 figures. Updated to match published versio
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