BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//SoPA UoE//Event Calendar//EN
X-WR-CALNAME:Particle Physics Theory Seminars
X-WR-CALDESC:Particle Physics Theory Seminars
X-PUBLISHED-TTL:PT12H
CALSCALE:GREGORIAN
METHOD:PUBLISH
BEGIN:VTIMEZONE
TZID:Europe/London
X-LIC-LOCATION:Europe/London
BEGIN:DAYLIGHT
TZOFFSETFROM:+0000
TZOFFSETTO:+0100
DTSTART:19810329T010000
RRULE:FREQ=YEARLY;BYMONTH=3;BYDAY=-1SU
TZNAME:BST
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:+0100
TZOFFSETTO:+0000
DTSTART:19961027T020000
RRULE:FREQ=YEARLY;BYMONTH=10;BYDAY=-1SU
TZNAME:GMT
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76484@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20170808T155931
LAST-MODIFIED:20171101T142224
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171025T140000
DTEND;TZID=Europe/London:20171025T150000
SUMMARY:Recent results and prospects from the NA62 experiment at CERN
DESCRIPTION:$K \\to \\pi \\nu\\nu$ is one of the theoretically cleanest me
son decay where to look for indirect effects of new physics complementary
to LHC searches. The NA62 experiment at CERN SPS is designed to measure th
e branching ratio of the $K^+\\to \\pi^+\\nu\\nu$ decay with 10% precision
. NA62 took data in 2015 and 2016 reaching the Standard Model sensitivity.
Recent results and prospects will be presented. Besides\, recently produc
ed upper limits on the rate of the charged kaon decay into a lepton and a
heavy neutral lepton (HNL) will also be shown.\n\nSpeaker:\n* Cristina Laz
zeroni (Birmingham University)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76484-recent-results-and-prospects
-from-the-na62-experiment-at-cern
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76881@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171017T172224
LAST-MODIFIED:20171101T142328
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171026T110000
DTEND;TZID=Europe/London:20171026T120000
SUMMARY:Nonperturbative renormalization and running of composite operators
in the Schrodinger Functional scheme
DESCRIPTION:In asymptotic free theories QCD-like\, the perturbative comput
ation of the RG evolution is limited to a short range scales at high energ
ies. In this talk I will present some recent (preliminary) results for the
non-perturbative first-principle computation of the renormalization and r
unning of the tensor currents ($N_f=0\,2$) and the BSM four-fermion operat
ors $\\Delta F=2 (N_f=2)$\, and of quark masses ($N_f=3$). Thanks to the r
ecursive finite-size scaling techniques in the Schrödinger Functional (SF
) renormalization scheme \, developed by the ALPHA collaboration\, it is p
ossible to provide the non-perturbative running over two orders of magnitu
de in scales\, from low energies $O(\\Lambda_{QCD})$ to high energies $O(M
_W)$ where perturbation theory can be safely applied.\n\nSpeaker:\n* David
Preti
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76881-nonperturbative-renormalizat
ion-and-running-of-composite-operators-in-the-schrodinger-functional
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76512@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20170825T115829
LAST-MODIFIED:20171218T164008
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171101T130000
DTEND;TZID=Europe/London:20171101T140000
SUMMARY:The Pion Mass and Decay Constant at NNNLO in Two-Flavour Chiral Pe
rturbation Theory
DESCRIPTION:Chiral perturbation theory is a low energy effective field the
ory built from the approximate chiral symmetry of QCD. The degrees of free
dom in this effective theory are the lightest pseudoscalar mesons\, and fo
r two quark flavours these are the pions. We have analytically calculated
the pion mass and decay constant at NNNLO in the chiral expansion\, i.e.
\, to order $p^{8}$\, in two-flavour chiral perturbation theory. In this t
alk\, based on hep-ph/1710.01901\, I will present the calculation as well
as show and discuss the numerical values of the coefficients in the leadin
g-log expansions of the quantities in question.\n\nSpeaker:\n* Nils Herman
sson Truedsson (Lund University)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76512-the-pion-mass-and-decay-cons
tant-at-nnnlo-in-two-flavour-chiral-perturbation-theory
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76856@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171010T093512
LAST-MODIFIED:20171108T155404
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171108T140000
DTEND;TZID=Europe/London:20171108T150000
SUMMARY:Fragmentation Functions of light charged hadrons
DESCRIPTION:I discuss the determination of the fragmentation functions (FF
s) of light charged hadrons from a wide set of single-inclusive electron-p
ositron annihilation cross section measurements. Specifically\, I focus on
the recent effort made by the NNPDF collaboration\, using a methodology b
ased on Monte Carlo sampling of experimental uncertainties and Neural Ne
tworks for parton parametrisation. I discuss the quality of the NNPDF dete
rmination\, including its stability upon inclusion of higher-order correct
ions\, and some of its implications in the investigation of the spin struc
ture of the nucleon and in the description of the hadron spectra measured
at the LHC.\n\nSpeaker:\n* Emanuele Roberto Nocera (Formerly School of Phy
sics & Astronomy\, University of Edinburgh)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76856-fragmentation-functions-of-l
ight-charged-hadrons
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76873@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171013T115101
LAST-MODIFIED:20171114T150420
STATUS:CANCELLED
DTSTART;TZID=Europe/London:20171115T140000
DTEND;TZID=Europe/London:20171115T150000
SUMMARY:[CANCELLED] *CANCELLED* Lattice QCD calculation of the nucleon axi
al coupling $g_A$
DESCRIPTION:The nucleon axial coupling $g_A$ controls the rate of neutron
beta decay and the strength of the nucleon-nucleon force that binds nuclei
together\, and therefore plays an important role in a wide range of physi
cal phenomena. From the structure of the proton and nuclei to the rate o
f neutrino emission from stars\, $g_A$ is ubiquitous in nuclear physics.
Though known experimentally to incredibly high precision (less than 0.2\\
%) its successful calculation from first principles has been elusive. Th
e calculation of $g_A$ from lattice QCD is considered by many a prerequisi
te to demonstrate the ability of lattice QCD to play a role in nuclear phy
sics analogous to the role it has played in particle physics over the past
\, say\, 20 years. I will discuss a recently completed calculation\, wit
h the CalLat collaboration\, of $g_A$ to an unprecedented precision of 1\\
%. The calculation\, which utilizes DWF valence quarks on the HISQ four
flavor ensembles\, achieves high precision thanks to a new computational s
trategy\, which I will highlight.\n\nSpeaker:\n* Christopher Bouchard (Uni
versity of Glasgow)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76873-cancelled-lattice-qcd-calcul
ation-of-the-nucleon-axial-coupling-ga
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76879@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171017T171531
LAST-MODIFIED:20171123T164404
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171122T140000
DTEND;TZID=Europe/London:20171122T150000
SUMMARY:Fundamental Composite Higgs Dynamics on the Lattice: SU(2) with Tw
o Fundamental Flavours
DESCRIPTION:I will present results on the non-perturbative dynamics of $SU
(2)$ gauge theory with two fundamental Dirac flavours. The theory provid
es a minimal template which has been used to design strongly coupled exten
sions of the Standard Model. It can for instance be used to build a mini
mal UV complete realisation in terms of a new strong sector with fermionic
matter of a pseudo Goldstone composite Higgs model. \n\nAfter summarisin
g the relevant lattice methods used in our simulations I will focus on the
scalar and pseudoscalar sector on the theory which are relevant for searc
hes of new exotic resonances at the LHC. I will then discuss the leading o
rder contribution to the scattering amplitude of Goldstone bosons\, which
are constrained by WW scattering measurements and could thus provide insig
hts on the electroweak symmetry breaking mechanism.\n\nSpeaker:\n* Vincent
Drach (Plymouth University)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76879-fundamental-composite-higgs-
dynamics-on-the-lattice-su2-with-two-fundamental-flavours
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76907@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171030T102111
LAST-MODIFIED:20171218T163955
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171124T143000
DTEND;TZID=Europe/London:20171124T153000
SUMMARY:Universality of next-to-leading power threshold effects for colour
less final states in hadronic collisions
DESCRIPTION:We consider the production of an arbitrary number of colour-si
nglet particles near partonic threshold\, and show that next-to-leading or
der cross sections for this class of processes have a simple universal for
m at next-to-leading power (NLP) in the energy of the emitted gluon radiat
ion. Our analysis relies on a recently derived factorisation formula for N
LP threshold effects at amplitude level\, and therefore applies both if th
e leading-order process is tree-level and if it is loop-induced. It holds
for differential distributions as well. The results can furthermore be see
n as applications of recently derived next-to-soft theorems for gauge theo
ry amplitudes. We use our universal expression to re-derive known results
for the production of up to three Higgs bosons at NLO in the large top mas
s limit\, and for the hadro-production of a pair of electroweak gauge boso
ns. Finally\, we present new analytic results for Higgs boson pair product
ion at NLO and NLP\, with exact top-mass dependence.\n\nSpeaker:\n* Leonar
do Vernazza (Formerly School of Physics & Astronomy\, University of Edinbu
rgh)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76907-universality-of-next-to-lead
ing-power-threshold-effects-for-colourless-final-states-in-hadronic
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76877@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171017T171253
LAST-MODIFIED:20171129T135150
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171129T140000
DTEND;TZID=Europe/London:20171129T150000
SUMMARY:Scattering of two spinning black holes in post-Minkowskian gravity
DESCRIPTION:The advent of gravitational-wave astronomy motivates detailed
study of the classical gravitational dynamics of spinning black holes in b
inary systems. Analytical calculations to those ends have traditionally
focused on post-Newtonian perturbation theory (expansion in $1/c$)\, natur
ally paired with an expansion in low spins. I will discuss a complimenta
ry approach using post-Minkowskian perturbation theory (expansion in $G$\,
as is more natural in QFT)\, paired with a nonperturbative treatment of t
he spins. New results for two-spinning-black-hole scattering at the firs
t post-Minkowskian order\, given in simple closed forms to all orders in s
pin\, reveal remarkable relationships between arbitrary-mass-ratio two-bod
y dynamics and test-body dynamics in a fixed background\, and between the
dynamics of spinning and nonspinning black holes. In pushing toward high
er orders in $G$\, the field will doubtlessly benefit from bringing a wide
range of techniques developed by particle physicists to bear on the probl
em of classical gravitational dynamics.\n\nSpeaker:\n* Justin Vines (Max P
lanck Institute for Gravitational Physics (Albert Einstein Institute))
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76877-scattering-of-two-spinning-b
lack-holes-in-post-minkowskian-gravity
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76833@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171002T161500
LAST-MODIFIED:20171206T152304
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20171206T140000
DTEND;TZID=Europe/London:20171206T150000
SUMMARY:QCD Resummation for BSM
DESCRIPTION:The existence of physics beyond the Standard Model (BSM) is we
ll motivated from both experimental and theoretical points of view. Howeve
r\, data from the 7/8 /13 TeV LHC (Run I and early Run II) have ruled out
new\, electroweak-scale states that couple appreciably to the Standard Mod
el. This suggests that new physics\, if it is indeed accessible at the LHC
\, is likely (i) light and very weakly coupled\, (ii) very heavy with siza
ble couplings\, or (iii) both. Interestingly\, such mass scales correspond
to regions of phase space for BSM collider processes where radiative corr
ections can be large\, making necessary their resummation. We present exam
ples of how QCD resummation can quantitatively and qualitatively change BS
M phenomenology\, particular for neutrino mass models\, at the 13 TeV LHC
and a prospective 100 TeV Very Large Hadron Collider.\n\nSpeaker:\n* Richa
rd Ruiz (University of Durham)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2017/76833-qcd-resummation-for-bsm
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77061@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180104T120919
LAST-MODIFIED:20180124T153049
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180117T140000
DTEND;TZID=Europe/London:20180117T150000
SUMMARY:Multi-hadron transition rates from lattice QCD
DESCRIPTION:In the late 1960s\, deep-inelastic scattering experiments\, in
which high energy leptons scatter off protons or other hadronic targets\,
proved crucial in solidifying our understanding of QCD as the quantum the
ory of the strong force. In such scattering events many hadrons are produc
ed in the final state\, but by considering inclusive rates (summed over th
e final states) one can define simpler observables that are described rema
rkably well by the underlying theory. However\, as the energy is lowered i
nto the regime of QCD resonances\, the high-energy description breaks down
and predictions become very challenging. The numerical technique of latti
ce QCD (LQCD)\, which has proven very successful in studying other low-ene
rgy quantities\, should also play an important role in reaching a comprehe
nsive\, quantitative picture for such multi-hadron rates. But this aim is
complicated by the fact that lattice calculations are defined in a finite
volume and with imaginary time\, whereas transition rates are infinite-vol
ume\, real-time observables. In this talk I will present a method for circ
umventing these issues based on an old idea from geophysicists Backus and
Gilbert\n\nSpeaker:\n* Maxwell T. Hansen (University of Mainz)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77061-multi-hadron-transition-rate
s-from-lattice-qcd
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76950@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171124T104041
LAST-MODIFIED:20180124T153204
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180124T140000
DTEND;TZID=Europe/London:20180124T150000
SUMMARY:Shedding light on new physics with Effective Field Theories
DESCRIPTION: Effective Field Theories (EFTs) are a powerful tool for inve
stigating the presence of new physics beyond the Standard Model. We will f
irst consider the Standard Model Effective Field Theory and discuss\, in a
“bottom-up” approach\, how its parameters can be constrained with glo
bal fit analyses without making assumptions on the UV physics.\n As a case
study I will present the results of a fit to electroweak data. The latter
exhibits instructive features\, among which the presence of two combinati
ons of Wilson coefficients that remain unconstrained when the analysis is
restricted to $2 \\to 2$ scattering processes and whose origin can be unde
rstood in terms of a reparameterization invariance. The second part of the
talk will follow a “top-down” perspective: considering the type-I see
saw model for neutrino masses\, EFT techniques will be employed to discuss
the possibility that the Higgs potential and electroweak scale are genera
ted radiatively in this scenario. This framework represents an alternative
approach to the hierarchy problem: here the Higgs mass is not stabilized
around the TeV scale\, but rather determined by radiative corrections at h
igher energies.\n\nSpeaker:\n* Ilaria Brivio (Niels Bohr Institute\, Kopen
hagen)
LOCATION:Room 6206\, JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76950-shedding-light-on-new-physic
s-with-effective-field-theories
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76863@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171010T202855
LAST-MODIFIED:20180208T011106
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180126T130000
DTEND;TZID=Europe/London:20180126T140000
SUMMARY:Structure of rapidity divergences in soft factors
DESCRIPTION:We discuss the structure of rapidity divergences that are pres
ented in the soft factors of transverse momentum dependent (TMD) factoriza
tion theorems. To provide the discussion on the most general level we cons
ider soft factors for multi-parton scattering. We show that the rapidity d
ivergences are result of the gluon exchanges with the distant transverse p
lane\, and are structurally equivalent to the ultraviolet divergences. It
allows to formulate and to prove the renormalization theorem for rapidity
divergences. The proof is made with the help the conformal transformation
which maps rapidity divergences to ultraviolet divergences. The theorem is
the systematic form of the factorization of rapidity divergences\, which
is required for the definition of TMD parton distributions. In particular\
, the definition of multi parton distributions is presented. The equivalen
ce of ultraviolet and rapidity divergences leads to the exact relation bet
ween soft and rapidity anomalous dimensions. Using this relation we derive
the rapidity anomalous dimension at the three-loop order.\n\nSpeaker:\n*
Alexey Vladimirov (Universitaet Regensburg)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76863-structure-of-rapidity-diverg
ences-in-soft-factors
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76858@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171010T094325
LAST-MODIFIED:20180131T140200
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180131T140000
DTEND;TZID=Europe/London:20180131T150000
SUMMARY:Boostrapping Non-planar Amplitudes
DESCRIPTION:I present a method of computing Feynman integrals by classifyi
ng the relevant function space and comparing with suitably chosen limits o
f their Mellin-Barnes representations.\n As an example\, I discuss the cal
culation of a five-point two-loop non-planar integral that has application
s for non-planar amplitudes of N=4 SYM.\n\nSpeaker:\n* Vladimir Mitev (Joh
annes Gutenberg Universitaet Mainz)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76858-boostrapping-non-planar-ampl
itudes
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76953@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171124T104728
LAST-MODIFIED:20180208T010439
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180207T140000
DTEND;TZID=Europe/London:20180207T150000
SUMMARY:Numerical methods and applications to two-loop calculations in the
Higgs sector
DESCRIPTION:The status of precision calculations will be briefly reviewed\
, focusing on calculations beyond one loop. Then an overview of the prog
ram SecDec\, which can be used for numerical multi-loop calculations\, wil
l be given.\n Some examples and phenomenological applications of the progr
am will be discussed\, in particular two-loop calculations in the Higgs se
ctor.\n\nSpeaker:\n* Gudrun Heinrich (Max-Planck Institute for Physics)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76953-numerical-methods-and-applic
ations-to-two-loop-calculations-in-the-higgs-sector
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76861@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171010T163355
LAST-MODIFIED:20180219T104619
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180216T130000
DTEND;TZID=Europe/London:20180216T140000
SUMMARY:Towards Decoding the Nature of Dark Matter at the LHC
DESCRIPTION:Determination of the nature of Dark Matter (DM) is one of the
most fundamental problems of particle physics and cosmology. If DM is
light enough and interacts with Standard Model particles directly or v
ia some mediators with a strength beyond the gravitational one\, it can be
directly produced at the Large Hadron Collider or future particle accel
erators. The typical signature from DM produced in particles collisions is
missing transverse energy\, MET\, due to the fact that they escape unde
tected from the experimental apparatus. We present a study for the complet
e set of dimension 5 and dimension 6 effective operators involving scalar\
, fermion and vector DM to explore the possibility to distinguish these op
erators and characterise the spin of DM. We have found that\, depending on
the spin of the DM\, the\n DM parts of the effective operators lead to a
different energy dependence of the cross-sections and to different distrib
utions of the invariant mass of the DM pair\, and consequently to differen
t MET distributions.\n\nWe have found that at the LHC with high lumino
sity\, certain classes of EFT operators can be distinguished from each oth
er and\, through this\, it is possible to characterise the spin of DM in s
ome cases.\n\nThis study can be directly applied beyond the EFT paradigm
.\n\nSpeaker:\n* Alexander Belyaev (University of Southampton)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76861-towards-decoding-the-nature-
of-dark-matter-at-the-lhc
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76859@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171010T094605
LAST-MODIFIED:20180302T142330
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180302T123000
DTEND;TZID=Europe/London:20180302T133000
SUMMARY:Recent four- and five-loop results in QCD
DESCRIPTION:We report on recent results in perturbative Quantum Chromodyna
mics and its generalization to Yang-Mills theories with fermions. We discu
ss the present status of four-loop $(N^3LO)$ calculations of the splitting
functions for the scale dependence (evolution) of the quark and gluon dis
tributions of hadrons\, in particular the flavour non-singlet quark-quark
case for which the complete result has been obtained in the limit of a lar
ge number of colours. Five-loop results are presented for the beta functio
n\, i.e.\, the running of the coupling constant\, for the hadronic decay o
f the Higgs boson in the heavy-top limit\, and for the lowest moment(s) of
the non-singlet splitting functions.\n\nSpeaker:\n* Andreas Vogt (Univers
ity of Liverpool)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76859-recent-four-and-five-loop-re
sults-in-qcd
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76955@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171124T105034
LAST-MODIFIED:20180315T160921
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180307T130000
DTEND;TZID=Europe/London:20180307T140000
SUMMARY:**AT 1PM** QCD corrections to the running of the electroweak coupl
ings
DESCRIPTION:The electromagnetic coupling and the weak mixing angle receive
sizeable contributions to their running from non-perturbative QCD effects
. The prospects for a future international linear collider suggest that th
e uncertainty on the running of the QED coupling could become a limiting f
actor in the global fit of the electroweak sector of the Standard Model. A
n experimental programme aiming at the measurement of the weak mixing angl
e at low-energies is also being carried out. I will present a lattice QCD
calculation of the running of these couplings in an energy regime\, around
the hadronic scale\, that is relevant for present experimental and phenom
enological studies.\n\nSpeaker:\n* Dr Gregorio Herdoiza (Universidad Autó
noma de Madrid)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76955-at-1pm-qcd-corrections-to-th
e-running-of-the-electroweak-couplings
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76956@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171124T105158
LAST-MODIFIED:20180302T161627
STATUS:CANCELLED
DTSTART;TZID=Europe/London:20180314T140000
DTEND;TZID=Europe/London:20180314T150000
SUMMARY:[CANCELLED] Gauge-invariant operators for charged hadrons
DESCRIPTION:I will discuss a procedure to generate states of charged hadro
ns with or without real photons\, in full QCD+QED on the lattice without r
elying on gauge fixing at any stage of the calculations. This procedure is
based on a formulation of QCD+QED in finite volume with C-parity boundary
conditions in the spatial directions\, which allow to define the charged
sector without spoiling locality. Electrically charged states are interpol
ated with a class of operators\, originally suggested by Dirac and built a
s functionals of the photon field\, that are invariant under local gauge t
ransformations.\n\nSpeaker:\n* Agostino Patella (Swansea University)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76956-gauge-invariant-operators-fo
r-charged-hadrons
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77366@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180212T060451
LAST-MODIFIED:20180315T161025
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180314T140000
DTEND;TZID=Europe/London:20180314T150000
SUMMARY:Descrambling Amplitudes and Integration using Cluster Coordinates
DESCRIPTION:Amplitudes in planar $N=4$ supersymmetric Yang-Mills theory ex
hibit a surprising amount of cluster-algebraic structure\, the physical me
aning of which remains largely obscure. After reviewing the various guises
in which this structure has been observed\, I will add a new set of obser
vations to this collection of curiosities. In particular\, I will present
new and striking cluster-algebraic decompositions of (the most complicated
parts of) two-loop seven- and eight-particle amplitudes in this theory\,
and will describe how cluster coordinates can even be used to tackle the p
roblem of integration directly---making it possible to integrate some of t
he Feynman integrals that contribute to these high-point amplitudes.\n\nSp
eaker:\n* Dr Andrew McLeod (Niels Bohr Institute\, Copenhagen)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77366-descrambling-amplitudes-and-
integration-using-cluster-coordinates
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-76958@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20171124T105500
LAST-MODIFIED:20180323T155746
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180321T140000
DTEND;TZID=Europe/London:20180321T150000
SUMMARY:Theta dependence in lattice gauge theories: physics and algorithms
DESCRIPTION:The aim of this talk is to give a broad overview of the physic
s related to theta dependence in gauge theories and to the problems encoun
tered in studying such topics by using lattice simulations. While these pr
oblems are generically classified as algorithmic problems\, their origin c
an in fact be understood using simple physical arguments. These arguments
also make it clear that this class of problems is typical not only of 4d g
auge theories\, but also of much simpler low dimensional theories\, that c
an be conveniently used as test beds for algorithm development.\n\nSpeaker
:\n* Dr Claudio Bonati (Pisa)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/76958-theta-dependence-in-lattice-
gauge-theories-physics-and-algorithms
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77191@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180124T101353
LAST-MODIFIED:20180328T153206
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180328T140000
DTEND;TZID=Europe/London:20180328T150000
SUMMARY:Loop Amplitudes from Ambitwistor Strings
DESCRIPTION:I will describe recent progress in the study of scattering amp
litudes in gauge theory and gravity via ambitwistor strings and the scatte
ring equations\, including loop level contributions. Ambitwistor strings a
re worldsheet models of quantum field theories\, inspired by string theory
. They naturally lead to a representation of amplitudes based on the scatt
ering equations. I will describe how the usual loop-level string formalism
of higher-genus Riemann surfaces can be avoided\, by turning a higher-gen
us surface into a nodal Riemann sphere\, with the nodes representing the l
oop momenta. This leads to new formulas for loop integrands in gauge theor
y and gravity\, with or without supersymmetry.\n\nSpeaker:\n* Ricardo Mont
eiro (Queen Mary University London)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77191-loop-amplitudes-from-ambitwi
stor-strings
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77402@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180305T114205
LAST-MODIFIED:20180412T084047
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180404T140000
DTEND;TZID=Europe/London:20180404T150000
SUMMARY:***ROOM CHANGE*** Extracting the timelike pion form factor from $\
\pi\\pi$ scattering in lattice QCD
DESCRIPTION:I will present results from an ongoing study of the $\\rho$ re
sonance in lattice QCD. The study of unstable states is challenging in num
erical Euclidean field theory. With only one open channel\, this is a benc
hmark system to study. It is furthermore interesting because it gives acce
ss to a calculation of the timelike pion form factor. This study also inte
grates with the existing Mainz programme for the calculation of the hadron
ic vacuum polarization contribution to the muon $g-2$. The current study f
ocuses on CLS 2-flavour lattices with pion masses ranging from $275$ to $4
51$ $\\mathrm{MeV}$ using $\\mathcal{O}(a)$ improved Wilson fermions.\n\nS
peaker:\n* Felix Erben (Johannes Gutenberg-Universität Mainz)
LOCATION:1501 (JCMB)
URL:https://www.ph.ed.ac.uk/events/2018/77402-room-change-extracting-the-t
imelike-pion-form-factor-from-pipi-scattering-in-lattice-qcd
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77193@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180124T101751
LAST-MODIFIED:20180420T094812
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180418T140000
DTEND;TZID=Europe/London:20180418T150000
SUMMARY:From flavor puzzles to new dynamics
DESCRIPTION:A particularly puzzling feature of the SM is its flavor sector
. It is the least constrained theoretically\, accounting for about two-thi
rd of the SM free parameters. At the same time\, the measured values of th
e quark and lepton masses and mixings show peculiar hierarchies\, and hint
at some yet unknown organizing principle. Phenomenologically\, in the abs
ence of this full theory of flavor\, most New Physics models have no reaso
n to preserve the SM flavor hierarchies and the associated accidental or a
pproximate symmetries. As a result\, they end up seriously constrained by
flavor observables\, and their typical scale are often pushed well beyond
the reach of the LHC.\n\nIn this talk\, our goal will be to show that the
peculiar hierarchies exhibited in the SM\, instead of hindering the presen
ce of New Physics at the TeV scale\, could actually point towards specific
new dynamics. We will discuss two examples. First\, we will detail the po
ssibility of TeV-scale baryon number violating processes\, which in a supe
rsymmetric context could explain the current absence of New Physics signal
s at the LHC. Then\, we will turn to the unification of quarks and leptons
. We will describe a mechanism by which the large top quark mass can rende
r its third-generation leptonic partner very light. This state is thus ide
ntified with the electron. We will then show how to implement dynamically
this mechanism\, using tree-level exchanges of TeV-scale vector leptons to
relate the quark and charged lepton flavor structures.\n\nSpeaker:\n* Chr
istopher Smith (Laboratory of subatomic Physics & Cosmology\, Université
Grenoble Alpes)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77193-from-flavor-puzzles-to-new-d
ynamics
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77749@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180412T083835
LAST-MODIFIED:20180425T144336
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180425T130000
DTEND;TZID=Europe/London:20180425T140000
SUMMARY:**at 1pm** Calculating the nucleon axial charge with lattice QCD
DESCRIPTION:The axial charge\, $g_A$\, is a fundamental property of the nu
cleon describing its coupling to the weak axial current and controlling th
e beta decay rate of the neutron. In principle\, $g_A$ is calculable fro
m first principles using lattice QCD. In fact\, the lattice community ha
s been attempting to calculate $g_A$ for two decades. However\, these ef
forts have been hindered by difficulties related to baryons on the lattic
e and associated systematic uncertainties. I will discuss a lattice QCD
calculation\, performed with members of the CalLat Collaboration\, of th
e nucleon axial charge with unprecedented accuracy and precision\, focusi
ng on techniques developed for and used in this calculation to address th
ese difficulties.\n\nSpeaker:\n* Christopher Bouchard (University of Glasg
ow)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77749-at-1pm-calculating-the-nucle
on-axial-charge-with-lattice-qcd
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77195@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180124T102036
LAST-MODIFIED:20180502T155129
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180502T140000
DTEND;TZID=Europe/London:20180502T150000
SUMMARY:Hadronic tau decays and the strong coupling
DESCRIPTION:I will discuss our recent determination of the strong coupling
from hadronic tau decays\, as measured by ALEPH and OPAL. This determinat
ion is controversial\, because the rather low tau mass makes it necessary
to disentangle non-perturbative effects that "contaminate" perturbation th
eory. In particular\, I will consider effects due to the violation of quar
k-hadron duality.\n\nSpeaker:\n* Professor Maarten Golterman (San Francisc
o State University)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77195-hadronic-tau-decays-and-the-
strong-coupling
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77197@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180124T102435
LAST-MODIFIED:20180420T094907
STATUS:CANCELLED
DTSTART;TZID=Europe/London:20180509T140000
DTEND;TZID=Europe/London:20180509T150000
SUMMARY:[CANCELLED] Evidence for the dynamical generation of naturally lig
ht fermion masses
DESCRIPTION: We present a numerical study of a model where a $SU(2)$ doub
let of non-abelian strongly interacting fermions is coupled to a complex s
calar field doublet via a Yukawa and an irrelevant Wilson-like term. Despi
te the presence of these two chiral breaking operators in the Lagrangian\,
an exact symmetry\, acting on all fields\, prevents UV power divergent fe
rmion mass corrections. In the phase where fermions are massless (Wigner p
hase) the Yukawa coupling can be set at a critical value where fermion chi
ral transformations become symmetries of the theory (up to cutoff effects)
. Numerical simulations of the critical theory in the Nambu-Goldstone phas
e give evidence for the non-perturbative generation of a UV finite fermion
mass term. We shall elaborate on possible consequences of exploiting this
dynamical mass generation phenomenon as an alternative to the Higgs mecha
nism.\n\nSpeaker:\n* Professor Giancarlo Rossi (Universita' di Roma "Tor V
ergata")
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77197-evidence-for-the-dynamical-g
eneration-of-naturally-light-fermion-masses
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77419@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180314T103304
LAST-MODIFIED:20180507T124353
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180516T140000
DTEND;TZID=Europe/London:20180516T150000
SUMMARY:Boundary CFTs and their central charges
DESCRIPTION:I will introduce some basic properties of boundary CFTs focusi
ng on the 3-dimensional case with planar boundary. The emphasis will be g
iven on the definition of energy-momentum tensor\, its correlators and th
e associated anomalies. I will then move on to discuss the momentum space
representation of these correlators and use it to determine the boundary R
icci scalar anomaly and its physical interpretation. In the remainder of t
he talk I will describe how to apply these methods using the method of i
mages to compute the anomaly in explicit examples.\n\nSpeaker:\n* Vladimir
Prochazka (Formerly School of Physics & Astronomy\, University of Edinbur
gh)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77419-boundary-cfts-and-their-cent
ral-charges
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77862@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180507T102123
LAST-MODIFIED:20180612T174438
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180606T140000
DTEND;TZID=Europe/London:20180606T150000
SUMMARY:Heavy physics contributions to neutrinoless double beta decay from
QCD
DESCRIPTION:If observed\, neutrinoless double beta decay would reveal viol
ations of symmetries fundamental to the Standard Model\, and would guarant
ee that neutrinos have nonzero Majorana mass. Relating nuclear decay rat
es to beyond the Standard Model (BSM) theories requires detailed knowledge
of non-perturbative QCD effects. Using lattice QCD and taking advantage o
f effective field theory methods\, we compute the model-independent leadin
g-order matrix elements of short-range operators\, which arise due to heav
y BSM mediators\, that contribute to this decay.\n Contributions from shor
t-range operators may prove to be equally important to those from long-ran
ge Majorana neutrino exchange.\n\nSpeaker:\n* Nicolas Garron University of
Plymouth
URL:https://www.ph.ed.ac.uk/events/2018/77862-heavy-physics-contributions-
to-neutrinoless-double-beta-decay-from-qcd
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77891@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180604T091133
LAST-MODIFIED:20180723T212741
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180719T140000
DTEND;TZID=Europe/London:20180719T150000
SUMMARY:Charmed baryons and heavy tetraquarks
DESCRIPTION:The study of heavy hadrons is passing through an incredible er
a with the discovery of numerous heavy subatomic particles. The study of c
harmed baryons and heavy tetraquarks are integral parts of this resurgence
in scientific interest to explore the spectrum of strongly interacting he
avy hadrons. I will first present the energy spectra of charmed baryons ob
tained using lattice QCD and discuss their implications on the recently ob
served states and future discovery. In the second part I will present our
recent results on the energy spectra of various tetraquark states with one
or more heavy quarks using lattice QCD. Presence of deeply bound doubly h
eavy tetraquarks and their possible future discovery will also be discusse
d.\n\nSpeaker:\n* Professor Nilmani Mathur (Tata Institute of Fundamental
Research\, Mumbai )
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77891-charmed-baryons-and-heavy-te
traquarks
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77942@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180705T100913
LAST-MODIFIED:20180723T212853
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20180725T140000
DTEND;TZID=Europe/London:20180725T150000
SUMMARY:Next-to-leading power correction in particle scattering near thres
hold
DESCRIPTION:I will discuss recent developments in the calculation of next-
to-leading power corrections in Drell Yan and other electroweak annihilati
on processes.\n\nSpeaker:\n* Leonardo Vernazza (Formerly School of Physics
& Astronomy\, University of Edinburgh)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77942-next-to-leading-power-correc
tion-in-particle-scattering-near-threshold
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77893@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180604T091446
LAST-MODIFIED:20181003T135600
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181003T140000
DTEND;TZID=Europe/London:20181003T150000
SUMMARY:Consistent perturbative fixed point calculations in gauge theories
DESCRIPTION:In order to obtain a better understanding of non-supersymmetri
c as well as supersymmetric gauge theories in the non-Abelian Coulomb phas
e it is important that we can reliably calculate scaling dimensions of com
posite operators. We show how to consistently calculate scaling dimensions
order by order in perturbation theory in a fully scheme independent and u
nambiguous manner. In supersymmetric gauge theories we find that the scal
ing dimension of all gauge invariant chiral operators as well as central
charges a\, b and c are astonishingly well approximated by a few loops com
putation throughout the entire conformal window. We also study how electr
ic magnetic duality emerges order by order within the conformal window. Fi
nally we study scaling dimensions in non-supersymmetric gauge theories (in
cluding QCD) to the maximum known order and provide evidence that a simi
lar precision is achieved here.\n\nSpeaker:\n* Professor Thomas Ryttov (C
P3 Origins\, Odense)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77893-consistent-perturbative-fixe
d-point-calculations-in-gauge-theories
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-77895@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180604T091739
LAST-MODIFIED:20181009T141821
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181010T140000
DTEND;TZID=Europe/London:20181010T150000
SUMMARY:A minimal theory of strongly-coupled dark baryons: spectrum predic
tions from lattice QFT
DESCRIPTION:As a simple model for dark matter\, we propose a QCD-like theo
ry based on $SU(2)$ gauge theory with one flavor of dark quark through a s
ingle flavor Dirac fermion in the fundamental representation. We use latti
ce simulations to investigate the properties of the lowest-lying hadrons.
Compared to QCD\, the theory has several interesting differences: there ar
e no Goldstone bosons or chiral symmetry restoration when the dark quark b
ecomes massless\; the usual global baryon number symmetry is enlarged to $
SU(2)_B$\, resembling isospin\; and baryons and mesons are unified togethe
r in $SU(2)_B$ iso-multiplets.\n We argue that the lightest baryon\, a vec
tor boson\, is a stable dark matter candidate and is a composite realizati
on of the hidden vector dark matter scenario.\n The model naturally includ
es a lighter state\, the analog of the $\\eta^\\prime$ in QCD\, for dark m
atter to annihilate into to set the relic density via thermal freeze-out.
Dark matter baryons may also be asymmetric\, strongly self-interacting\, o
r have their relic density set via $3 \\to 2$ cannibalizing transitions.\n
We discuss some experimental implications of coupling dark baryons to the
Higgs portal.\n\nSpeaker:\n* Dr Anthony Francis (CERN)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB
URL:https://www.ph.ed.ac.uk/events/2018/77895-a-minimal-theory-of-strongly
-coupled-dark-baryons-spectrum-predictions-from-lattice-qft
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78229@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180927T124045
LAST-MODIFIED:20181012T105726
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181017T140000
DTEND;TZID=Europe/London:20181017T150000
SUMMARY:Isospin Breaking Corrections to the Hadronic Vacuum Polarisation f
rom the Lattice
DESCRIPTION:The anomalous magnetic moment of the muon is one of the most p
recisely measured quantities in particle physics and can therefore serve a
s a high-precision test of the Standard Model. The lagest uncertainty in t
he Standard Model prediction comes from the hadronic sector\, where the le
ading contribution is given by the Hadronic Vacuum Polaisation (HVP). A de
termination of the HVP from lattice QCD aiming at sub-percent level precis
ion requires to include isospin breaking corrections in the computation. I
will discuss how these corrections can be included in a lattice calculati
on and present results for the QED and strong isospin breaking corrections
to the HVP at physical quark masses.\n\nSpeaker:\n* Dr Vera Guelpers (Sch
ool of Physics & Astronomy\, University of Edinburgh)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2018/78229-isospin-breaking-corrections
-to-the-hadronic-vacuum-polarisation-from-the-lattice
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78183@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180911T141639
LAST-MODIFIED:20180911T141639
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181024T140000
DTEND;TZID=Europe/London:20181024T150000
SUMMARY:Chris Bouchard (tba)
DESCRIPTION:tba\n\nSpeaker:\n* Christopher Bouchard (University of Glasgow
)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2018/78183-chris-bouchard-tba
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78195@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180918T083414
LAST-MODIFIED:20180920T113502
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181031T140000
DTEND;TZID=Europe/London:20181031T150000
SUMMARY:Two-loop five-point massless QCD amplitudes within the IBP approac
h
DESCRIPTION:I will discuss my recent paper hep-ph/1805.09182\, where we so
lve the integration-by-parts (IBP) identities needed for the computation o
f any planar two-loop five-point massless amplitude in QCD. We also derive
some new results for the most complicated non-planar topology with irredu
cible numerators of power as high as six. We do this by applying a new str
ategy for solving the IBP identities which scales better for problems with
a large number of scales and/or master integrals. Our results are a proof
of principle that the remaining non-planar contributions for all two-loop
five-point massless QCD amplitudes can be computed in analytic form.\n\nS
peaker:\n* Herschel Chawdhry (University of Cambridge)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2018/78195-two-loop-five-point-massless
-qcd-amplitudes-within-the-ibp-approach
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78197@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180918T083642
LAST-MODIFIED:20180918T083642
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181107T130000
DTEND;TZID=Europe/London:20181107T140000
SUMMARY:*at 1pm* Martijn Hidding (tba)
DESCRIPTION:tba\n\nSpeaker:\n* Martijn Hidding (Trinity College Dublin)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2018/78197-at-1pm-martijn-hidding-tba
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78225@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180927T104148
LAST-MODIFIED:20180927T104148
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181114T140000
DTEND;TZID=Europe/London:20181114T150000
SUMMARY:tba (Nils Asmussen)
DESCRIPTION:tba\n\nSpeaker:\n* Nils Asmussen (University of Southampton)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2018/78225-tba-nils-asmussen
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78182@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180911T124846
LAST-MODIFIED:20180919T134106
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20181212T140000
DTEND;TZID=Europe/London:20181212T150000
SUMMARY:Cluster Adjacency and the NMHV 7-particle amplitude in N=4 super Y
ang-Mills at 4 loops
DESCRIPTION:The idea of constructing scattering amplitudes from their sing
ularities has been a very powerful method for their computation. We introd
uce the principle of Cluster Adjacency\, which governs the analytic struct
ure of amplitudes at tree and loop level. We use this to compute the NMHV
scattering amplitude of seven particles in N=4 super Yang-Mills at four lo
ops.\n\nSpeaker:\n* Dr Ömer Gürdoğan (University of Southampton)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2018/78182-cluster-adjacency-and-the-nm
hv-7-particle-amplitude-in-n4-super-yang-mills-at-4-loops
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78223@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180927T103105
LAST-MODIFIED:20180927T103105
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20190116T140000
DTEND;TZID=Europe/London:20190116T150000
SUMMARY:Michele Levi (tba)
DESCRIPTION:PPT seminar on 16/01\n\nSpeaker:\n* Dr Michele Levi (Institut
de Physique Thorique)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2019/78223-michele-levi-tba
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78227@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180927T112506
LAST-MODIFIED:20180927T112506
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20190213T140000
DTEND;TZID=Europe/London:20190213T150000
SUMMARY:Jan Plefka (tba)
DESCRIPTION:tba\n\nSpeaker:\n* Professor Jan Plefka (Humboldt University B
erlin)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2019/78227-jan-plefka-tba
END:VEVENT
BEGIN:VEVENT
CLASS:PUBLIC
UID:EVENT-78198@www.ph.ed.ac.uk
DTSTAMP:20181021T035235
CREATED:20180918T083812
LAST-MODIFIED:20180918T083812
STATUS:CONFIRMED
DTSTART;TZID=Europe/London:20190220T140000
DTEND;TZID=Europe/London:20190220T150000
SUMMARY:Maurizio Piai (tba)
DESCRIPTION:tba\n\nSpeaker:\n* Maurizio Piai (Swansea University)
LOCATION:Higgs Centre Seminar Room\, 4305 JCMB\, KB
URL:https://www.ph.ed.ac.uk/events/2019/78198-maurizio-piai-tba
END:VEVENT
END:VCALENDAR