YTF 11
from
Wednesday, December 19, 2018 (11:00 AM)
to
Thursday, December 20, 2018 (1:00 PM)
Monday, December 17, 2018
Tuesday, December 18, 2018
Wednesday, December 19, 2018
12:30 PM
12:30 PM  1:30 PM
1:30 PM
1:30 PM  2:30 PM
2:30 PM
2:30 PM  2:40 PM
Room: CM101
2:40 PM
Applications of gauge/gravity duality

Matthew Russell
(Southampton)
Applications of gauge/gravity duality
Matthew Russell
(Southampton)
2:40 PM  3:00 PM
Room: CM107
This talk will discuss scenarios where the gauge/gravity duality can be applied to nonperturbative regimes in physics. The standard model explains many phenomena seen in nature but relies on techniques that only work in small coupling. The gauge/gravity duality is a way in which we can try to obtain theoretical predictions for areas such as strongly coupled condensed matter and the low energy regime of QCD. Specifically this talk will focus on momentum dissipation effects on zero sound in strange metals and the benefit of exploring holographic imaginary chemical potential in the QCD phase diagram.
QuasiDegenerate Vacua in the KSVZ axion model; A minimal approach to dark energy and dark matter

Amy LloydStubbs
(Lancaster University)
QuasiDegenerate Vacua in the KSVZ axion model; A minimal approach to dark energy and dark matter
Amy LloydStubbs
(Lancaster University)
2:40 PM  3:00 PM
Room: CM101
I will present a study of the KSVZ axion model with quasidegenerate vacua as a minimal model for dark energy and dark matter. I will review axions as dark matter and provide an explanation for dark energy in the form of a difference in vacuum energy density between the electroweak vacuum and a second degenerate minimum in the effective potential, which can be achieved via the scalar threshold effect.
3:05 PM
Coincident M5branes and dual singular geometries

Callum Brodie
(University of Oxford)
Coincident M5branes and dual singular geometries
Callum Brodie
(University of Oxford)
3:05 PM  3:25 PM
Room: CM107
Through a web of string dualities, M5brane configurations in Mtheory can be mapped to geometrical features. In particular, I will discuss this map via heterotic/Ftheory duality, using a HoravaWitten description of heterotic $\mathrm{E}_8 \times \mathrm{E}_8$ string theory as the connection to Mtheory. Intersecting or coincident M5branes are mapped to singular base geometries in Ftheory, which also correspond to singular geometries in Type IIB string theory. I will explain these dualities, and if I have time I will discuss geometrical transitions corresponding to deforming M5brane configurations and point out some cute connections with toric geometry.
Production and thermalisation of isolated sectors

Hannah Tillim
(University of Oxford)
Production and thermalisation of isolated sectors
Hannah Tillim
(University of Oxford)
3:05 PM  3:25 PM
Room: CM101
An increasingly attractive alternative to the WIMP model is that of an `isolated' dark sector  i.e. one which interacts with the standard model only via gravity and which therefore is unbounded by direct detection. We present a possible production mechanism for this sector in the early Universe (Hawking emission from primordial black holes) as well as predictions for the subsequent evolution and ultimate fate of initially highly nonequilibrium populations.
3:30 PM
Central charge of selfdual strings from holography

Ronnie Rodgers
(University of Southampton)
Central charge of selfdual strings from holography
Ronnie Rodgers
(University of Southampton)
3:30 PM  3:50 PM
Room: CM107
Mtheory is a candidate for a theory of quantum gravity. Its fundamental objects are called M2branes and M5branes. The lowenergy theory describing coincident M5branes is poorly understood in many respects, with holography providing one of the most useful tools to further that understanding. It is known that the theory should possess solitonic solutions called "selfdual strings". I will review the holographic description of these strings, and show how calculation of entanglement entropy provides a way of calculating an important quantity characterising them: their central charge.
Shedding Light on the Initial Conditions of Inflation with the Eisenhart Lift

Kieran Finn
(University of Manchester)
Shedding Light on the Initial Conditions of Inflation with the Eisenhart Lift
Kieran Finn
(University of Manchester)
3:30 PM  3:50 PM
Room: CM101
The Hot Big Bang model of cosmology requires very finelytuned initial conditions in order to explain the degree of flatness and homogeneity we observe in the Universe today. This has led the community to embrace the theory of inflation, since it readily explains these features. But are the initial conditions required to initiate inflation more or less finelytuned than those required by the Hot Big Bang? Although there are several qualitative arguments to suggest that inflation should happen generically, attempts to quantify these have led to ambiguous answers due to the infinite measure of the total phase space. Previous studies have regularised this measure to get an unambiguous answer, but the results are strongly dependent on the regularisation technique used with some authors concluding that inflation is exponentially likely while others conclude that it is exponentially unlikely. The Eisenhart lift, which was recently applied to field theories for the first time, is a technique that allows one to convert a theory described by a Lagrangian into an equivalent geometric system. Applying the Eisenhart lift to inflation, one can construct a manifold such that each point represents a different initial condition. Both the total volume of this manifold and the volume that leads to inflation is finite. Thus, we can finally answer quantitatively how finelytuned the initial conditions of inflation are without the need for a regulator.
3:55 PM
Anisotropies in the stochastic gravitationalwave background

Alex Jenkins
(King's College London)
Anisotropies in the stochastic gravitationalwave background
Alex Jenkins
(King's College London)
3:55 PM  4:15 PM
Room: CM101
In the new era of gravitationalwave astronomy, one of the most exciting targets for future observations is the stochastic gravitationalwave background (SGWB). While we have yet to detect the SGWB, we expect that by studying the angular power spectrum of its anisotropies, we may learn about the largescale structure of the Universe (analogous to studies of the CMB). With this in mind, we develop detailed models of the SGWB anisotropies from two important sources of gravitational waves: unresolved compact binary coalescences, and cosmic strings.
The orientifold quotient of giant gravitons

Christopher LewisBrown
(Queen Mary University of London)
The orientifold quotient of giant gravitons
Christopher LewisBrown
(Queen Mary University of London)
3:55 PM  4:15 PM
Room: CM107
The AdS/CFT correspondence links type IIB string theory on $AdS_5 \times S^5$ to $\mathcal{N}=4$ super YangMills with gauge group $U(N)$. In 1998, Witten showed that taking an orientifold quotient of the $S^5$ factor  identifying antipodal points so as to replace $S^5$ with $\mathbb{RP}^5$  can be understood on the gauge theory side by replacing the $U(N)$ gauge group with either $SO(N)$ or $Sp(N)$. I will talk about this quotient from the gauge theory point of view, focusing on the halfBPS sector. This corresponds to taking the quotient of rotating D3brane states, also called giant gravitons. The mathematics of this quotient leads to surprising connections with plethysms and domino tableaux, which can be tied back to intuitive notions of how the orientifold acts on the branes.
4:20 PM
Tea, Coffee and Biscuits
Tea, Coffee and Biscuits
4:20 PM  4:45 PM
4:45 PM
Bifurcations in the RGFlow of QCD

Folkert Kuipers
Bifurcations in the RGFlow of QCD
Folkert Kuipers
4:45 PM  5:05 PM
Room: CM101
In this talk, I’ll discuss the connection between the theory of dynamical systems and renormalization group flows in quantum field theory. In particular, I’ll apply numerical methods from bifurcation analysis to study the RGflow of an effective model for QCD with a fourfermi interaction and an arbitrary number of colors and massless flavors. Using bifurcation analysis techniques, new fixed points are found in and close to the conformal window. Particular focus will be given to the way in which the fixed points (dis)appear in the model, and how this affects the scaling dimensions of the (ir)relevant operators. Furthermore, I’ll discuss how the fixed point structure of the RGflow changes when a scalar field coupling through a Yukawa interaction is added to the model.
Fermionically Generated Superstrata

Nejc Ceplak
(Queen Mary, University of London)
Fermionically Generated Superstrata
Nejc Ceplak
(Queen Mary, University of London)
4:45 PM  5:05 PM
Room: CM107
The aim of the talk is to present the construction of a new family of smooth horizonless solutions of supergravity that have the same charges as the supersymmetric D1D5P black hole. We will begin with a brief review of the Fuzzball proposal for black holes, which states that at the length scale of the horizon a new, fuzzy, phase takes over, allowing outside observers to distinguish between different microstates of the black hole. We will then focus on the three charge supersymmetric D1D5P black hole and review some of its microstate geometries. We then present a method of obtaining a new family of solutions using supersymmetry generators. The motivation behind this construction is coming from the dual CFT multiplet structure, where these fermionic generators are used to create new linearly independent states in the theory. On the gravity side the geometries dual to these new states are generated by the Killing spinors of AdS$_3 \times S^3 \times T^4$. Hence we present the explicit form of these spinors and use them to construct new solutions to the supergravity equations. Finally we present these new solutions and show that they are simpler than the ones previously known with having a fewer number of excited fields.
5:10 PM
Global Fixed Points of Scalar and Fermionic Theories

Bradley Garland
(University of Sussex)
Global Fixed Points of Scalar and Fermionic Theories
Bradley Garland
(University of Sussex)
5:10 PM  5:30 PM
Room: CM101
Interacting fixed points in three dimensions have been investigated using modern renormalisation group methods. Investigations focus on the seminal WilsonFisher fixed point solution in O(N) symmetric scalar theories and asymptotically safe UV fixed points in fermionic GrossNeveu models. The main novelty of the study is the use of Padé approximants. Padé approximants have been used to extend local fixed point data that is obtained from polynomial expansions and hence, only valid for small field values to global fixed point solutions for all field values. For both the scalar and fermionic theories this approach is tested in the Large N limit where explicit analytic fixed point solutions can be found. Particular emphasis is put on the large real field and the large imaginary field limits, and converginglimiting singularities in the complex field plane. Finite N models have also been tested for the O(N) symmetric scalar theories. Here exact solutions are not accessible and Padé approximants have been used to make predictions beyond the radius of convergence of polynomial expansions. Padé approximants have also been used to locate singularities exhibited by the given complexified fixed point solutions. In doing this it is seen that the singularities exhibited by Padé approximants themselves form patterns of defects in the complexified field plane that are intimately linked to their ability to converge to high accuracy.
Heterotic M2Branes

Rishi Mouland
(King’s College London)
Heterotic M2Branes
Rishi Mouland
(King’s College London)
5:10 PM  5:30 PM
Room: CM107
MTheory has been conjectured as a single theory in which we can find each of the various superstring theories, and as such provides a UV completion of 11d supergravity. Instead of strings, we have M2branes and M5branes. The classic HoravaWitten result says that a compactification of Mtheory on $S^1/\mathbb{Z}_2$ retrieves the $E_8\times E_8$ heterotic theory, with the wrapped M2brane as the "fundamental" string. In this work, we reproduce this result from the perspective of the ABJM theory, a world volume theory conjectured to capture the lowenergy behaviour of multiple M2branes. In particular, we find that the subtle nature of ChernSimons matter theories delivers a new perspective on the GSO projection and the nonsupersymmetric $SO(16)\times SO(16)$ heterotic theory.
5:35 PM
Renormalization Group Properties of the Conformal Mode

Matthew Kellett
(University of Southampton)
Renormalization Group Properties of the Conformal Mode
Matthew Kellett
(University of Southampton)
5:35 PM  5:55 PM
Room: CM101
The renormalization group properties of a QFT are of profound importance to the theory. In quantum gravity, one runs into the problem that the kinetic term for the dilaton (or conformal mode) has the wrong sign, causing the Euclidean partition function to be (worse than usually) illdefined. Imposing a new quantization condition allows us to not only make sense of this, but also potentially would allow us to use standard RG techniques to quantize gravity. We see that the effect of resolving this conformal mode "instability" (as described by Hawking et. al.) is to constrain the size of the manifold by its homogeneity. I will present an outline of how this is done and some results from studies of the torus. If time permits, I will also outline ongoing and future work in this area.
Supergravity on a 3Torus: Quantum Linearisation Instabilities with a Supergroup

Lasse Schmieding
(University of York)
Supergravity on a 3Torus: Quantum Linearisation Instabilities with a Supergroup
Lasse Schmieding
(University of York)
5:35 PM  5:55 PM
Room: CM107
For closed universes, the Einstein equations (EE) are linearisation unstable. Perturbing around any background with Killing symmetries the linearised EE admit solutions which are not themselves linearisations of solutions to the nonlinear EE. To control these spurious solutions, quadratic linearisation stability conditions are imposed. However, in the quantum theory these stability conditions require that all physical states must be invariant under the background symmetries, which can complicate the construction of the physical Hilbert space. I will review linearisation stability conditions in both classical and quantum gravity, and then discuss a simple supersymmetric model to study quantum linearisation instabilities with a supergroup.
6:00 PM
Tea, Coffee and Biscuits
Tea, Coffee and Biscuits
6:00 PM  6:20 PM
6:20 PM
6:20 PM  7:20 PM
Room: CM101
7:30 PM
7:30 PM  8:30 PM
Room: Bransden Room
Thursday, December 20, 2018
9:00 AM
Clustering algorithms for bjets from BSM Higgs Bosons.

Billy Ford
(University of Southampton)
Clustering algorithms for bjets from BSM Higgs Bosons.
Billy Ford
(University of Southampton)
9:00 AM  9:20 AM
Room: CM101
It is long established that the Standard Model is not a complete theory of nature and at the LHC we hope to see hints of some new physics beyond our current understanding. This project seeks to improve current techniques of jet clustering, in particular from some extended BSM Higgs sector, such as those in 2 Higgs Doublet Models, which include additional particles alongside the 125 GeV SM Higgs detected in 2012.
What do knots, quantum computation and field theories have in common?

Rajath Radhakrishnan
(Queen Mary University of London)
What do knots, quantum computation and field theories have in common?
Rajath Radhakrishnan
(Queen Mary University of London)
9:00 AM  9:20 AM
Room: CM107
Knots are deceivingly simple mathematical objects. Showing whether two knots are the same or not is a hard problem. While it can be done easily by inspection for simple knots, the problem becomes hard very quickly. Ideally, to distinguish between inequivalent knots we have to define knot invariants. At first sight, this may not have anything to do with quantum computation or field theories. However, it turns out that these subjects are intimately related to each other through an algebraic object called a modular tensor category (MTC). In this talk, I will describe an MTC and explain how it forms the bridge between the aforementioned topics.
9:25 AM
A Gentle Introduction to Supersymmetric Localization

Matthew Renwick
(Department of Mathematical Sciences, Durham University)
A Gentle Introduction to Supersymmetric Localization
Matthew Renwick
(Department of Mathematical Sciences, Durham University)
9:25 AM  9:45 AM
Room: CM107
Localization is a powerful technique utilised in supersymmetric field theories to reduce troublesome infinite dimensional path integrals to pleasant finite dimensional integrals. The aim of this talk is to provide an introduction to this topic and discuss its applications. In particular, I will explain how this technique is used to compute the exact partition function and the expectation values for certain operators in supersymmetric theories.
Light charged Higgs boson with dominant cb decay from 3HDM and its search at LHC and future colliders

Muyuan Song
(University of Southampton)
Light charged Higgs boson with dominant cb decay from 3HDM and its search at LHC and future colliders
Muyuan Song
(University of Southampton)
9:25 AM  9:45 AM
Room: CM101
I am working with Professor Stefano Moretti and Doctor Andrew Akeroyd on charged Higgs phenomenology in the University of Southampton recently. We posted the paper in October 2018 on arXiv:1810.05403. The possibility of a light charged Higgs boson H± that decays predominantly to quarks (cs and/or cb) and with a mass in the range 80 GeV ≤ mH± ≤ 90 GeV is studied in the context of Three HiggsDoublet Models (3HDMs). At present the Large Hadron Collider (LHC) has little sensitivity to this scenario, and currently the best constraints are from LEP2 and Tevatron searches. The branching ratio of H± → cb can be dominant in two of the five types of 3HDM, and we determine the parameter space where this occurs. The decay H± → cb has recently been searched for at the LHC for the first time, and with increased integrated luminosity one would expect sensitivity to the region 80 GeV ≤ mH± ≤ 90 GeV due to the smaller backgrounds with respect to H± → cs decays.
9:50 AM
Different aspects of single top quark and DM channel

Charanjit Kaur Khosa
(University of Sussex)
Different aspects of single top quark and DM channel
Charanjit Kaur Khosa
(University of Sussex)
9:50 AM  10:10 AM
Room: CM101
Recently it has been pointed out that associated production of dark matter with single top quark could also provide an interesting reach for dark matter (DM) searches at LHC. I will discuss this in context of simplified dark matter models and in two Higgs doublet model. The top quark produced via this channel is polarized and the polarization depends on the CP of the mediator (simplified dark matter model with spin0 mediators). I will also talk about the top polarization sensitive angular observables, which along with the crosssection, could be used to probe the CP property of the mediator.
Resurgence and NonPerturbative Physics

Philip Glass
(Durham University)
Resurgence and NonPerturbative Physics
Philip Glass
(Durham University)
9:50 AM  10:10 AM
Room: CM107
Divergent perturbation series are prevalent in all of physics. Notable examples include sums of Feynman diagrams in QFT and sums over Riemann surfaces in string scattering. I will first give a brief introduction to Resurgence theory, starting with ways of summing divergent series which will lead us to Borel summation and then looking at the analytic continuation of the path integrals which will lead us to Resurgence theory. Time permitting I will then discuss Resurgence in the context of $\mathcal{N}=(2,2)$ on the 2sphere using results from SUSY Localization.
10:15 AM
NonMinimal Flavour Violation in the MSSM from a flavoured SU(5) GUT

Sam Rowley
(University of Southampton)
NonMinimal Flavour Violation in the MSSM from a flavoured SU(5) GUT
Sam Rowley
(University of Southampton)
10:15 AM  10:35 AM
Room: CM101
We study flavourviolation in a SU(5) setup inspired by flavoured GUTs. We investigate the impact of various observables at low scales on the highenergy parameters of the theory including mu>e gamma and the relic density of dark matter. An interesting interplay between the quark and lepton sectors becomes apparent due to the cohabitation of various fields in representations of the unifying group. Correlations between high scale parameters in the context of current experimental flavour data are shown to manifest. We show that movement away from the Minimal Flavour Violation paradigm is perfectly possible within the context of current limits.
Towards a classification of supersymmetric spacetimes

Ross Grassie
Towards a classification of supersymmetric spacetimes
Ross Grassie
10:15 AM  10:35 AM
Room: CM107
In this talk, we present a deformation theoretic approach to classifying supersymmetric spacetimes. It is a postulate of general relativity that spacetime is described by a fourdimensional Lorentzian manifold. However, it is not always convenient to use this description. For example, it may be easier to take the Newtonian limit and work with theories at lower energies. These nonrelativistic spacetimes are still useful descriptions and should be incorporated in our classification. To this end, we notice that the above postulate has an important consequence: the spacetime manifold is fully described by its relativity group. Therefore, we do not ask for manifolds whose relativity group is the Poincaré group, but for geometries with some relativity group. We will show that these groups may be described by kinematical Lie algebras and give the classification of these algebras. We then show how this programme is being extended to the supersymmetric case.
10:40 AM
Tea, Coffee and Biscuits
Tea, Coffee and Biscuits
10:40 AM  11:00 AM
11:00 AM
Gravity amplitudes, observables and classical scattering

Maybee Ben
(University of Edinburgh)
Gravity amplitudes, observables and classical scattering
Maybee Ben
(University of Edinburgh)
11:00 AM  11:20 AM
Room: CM107
Modern amplitudes techniques offer the tantalising possibility of greatly simplifying theoretical predictions for precision gravitational wave astronomy. One exciting example is the double copy, an enigmatically simple connection between YangMills theory and gravity. In this talk I will discuss our recent work on rigorously obtaining classical scattering observables from quantum amplitudes, and why the double copy makes this pertinent for gravitational radiation.
Higher Order QCD Calculations with NNLOJET

Duncan Walker
(IPPP, Durham University)
Higher Order QCD Calculations with NNLOJET
Duncan Walker
(IPPP, Durham University)
11:00 AM  11:20 AM
Room: CM101
I will present some recent results of higher order QCD calculations in vector boson processes at colliders using the Monte Carlo framework NNLOJET. Recent developments are opening up a new world of precision phenomenology for study, improving our understanding of QCD/EW interactions at a fundamental level.
11:25 AM
Developing an amplitude level parton shower.

Jack Holguin
(The University of Manchester)
Developing an amplitude level parton shower.
Jack Holguin
(The University of Manchester)
11:25 AM  11:45 AM
Room: CM101
Perturbative QCD suffers from multitudes of large logarithms, arising from the miscancellation of infrared poles. These logarithms can cause enhancements of high order terms and spoil perturbative convergence. Historically there has been two disjoint approaches to solving this problem; resummations and parton showers. Nowadays resummations are performed at high accuracy and are rigorously defined, but they are very time consuming. Parton showers are all purpose and can be implemented computationally. However modern showers are still far from a rigorous definition. We present a new algorithm that aims to unify these two approaches.
Semiclassical gravity in the far field of stars and black holes

Jake Percival
(University of Sheffield)
Semiclassical gravity in the far field of stars and black holes
Jake Percival
(University of Sheffield)
11:25 AM  11:45 AM
Room: CM107
In semiclassical gravity, the expectation value of the stressenergy operator $\left\langle T_{\mu\nu}\right\rangle$ is an infinite quantity. To avoid having to renormalize it, one can calculate the difference in $\left\langle T_{\mu\nu}\right\rangle$ between a pair of quantum states in such a manner that the divergent parts cancel. However, another technique explored more recently is to take the difference in $\left\langle T_{\mu\nu}\right\rangle$ between two different spacetimes, while in the same quantum state. I will summarize prior work on this method and detail how we have applied it to calculate the difference $\Delta\left\langle T_{\mu\nu}\right\rangle$ between the spacetimes of a nonNewtonian star and a Schwarzschild black hole.
11:50 AM
Nonperturbative aspects of Sp(2N) gauge theories.

Jack Holligan
(Swansea University)
Nonperturbative aspects of Sp(2N) gauge theories.
Jack Holligan
(Swansea University)
11:50 AM  12:10 PM
Room: CM101
The discovery in 2012 of the Higgs boson provided evidence for our understanding of the origin of mass. However there still remain some unanswered questions one of which is the "Naturalness Problem". Like the other fundamental particles, the Higgs acquires loop corrections to its mass due to its interaction with the quarks, the leptons and itself. If we impose an ultraviolet cutoff, $\Lambda_{\text{UV}}$, on the Standard Model, these corrections depend quadratically on $\Lambda_{\text{UV}}$. If $\Lambda_{\text{UV}}$ is sent to infinity, a very large counter term is required to cancel out the quadratic divergence arising from the loop corrections. In order to produce the small observed Higgs mass of $125$ GeV, the counter term must be computed to a precision so high that it is not only unnatural  hence the name  but far beyond experimental reach. One way to resolve this problem is to treat the Higgs not as a fundamental particle but as a constituent one (like the proton or neutron). The need for finetuning is simply an effect of the approximation of the Higgs as a fundamental particle breaking down. The compositeness deals with the issue of fine tuning and the subsequent low mass is achieved by corollary of Goldstone's Theorem. When a symmetry is explicitly broken (e.g. by a mass term) there exists a light boson for each broken generator (as opposed to a massless boson in the case of spontaneous symmetry breaking). The explicit breaking of a new symmetry group could give rise to what is observed as the Higgs boson. The combination of Goldstone's Theorem and a new symmetry group have potential to explain the lowmass Higgs as a composite particle without the need for finetuning. Candidate symmetries are the Symplectic Groups (denoted as Sp($2N$)). Observable quantities of such a Quantum Field can be computed on the lattice and their experimental detection would provide evidence for same.
Renormalised vacuum polarisation on topological black holes

Thomas Morley
(University of Sheffield)
Renormalised vacuum polarisation on topological black holes
Thomas Morley
(University of Sheffield)
11:50 AM  12:10 PM
Room: CM107
Antide Sitter spacetime is a solution of Einstein’s equations with a negative cosmological constant. This fact allows for unusual black hole solutions with nonspherical horizon topology. We calculate the renormalised vacuum polarisation for black holes with spherical, flat and hyperbolic event horizons, following the “extended coordinates” method, which uses a modesum representation for the Hadamard parametrix. Renormalisation counter terms are subtracted from the Green’s function modebymode, leaving each individual term manifestly finite.
12:15 PM
Isospin breaking corrections to leptonic decay rates on the lattice

James Richings
(stfc southampton phd student and former durham undergraduate student)
Isospin breaking corrections to leptonic decay rates on the lattice
James Richings
(stfc southampton phd student and former durham undergraduate student)
12:15 PM  12:35 PM
Room: CM101
Lattice QFT is a method for calculating nonperturbative physics and has been used extensively to calculate properties of low energy QCD. Over the last decade calculation's of a number of nonperturbative QCD quantities have reached a good precision, with agreement from across the lattice community. In general isospin breaking (IB) effects have not been included in these calculations because until now IB effects have not been a limiting source of systematic error. Isospin breaking effects enter in two ways, the difference in the mass of the up and down quark (strong IB) and the difference in the QED charge of up and down type quarks (QED IB). Considering power counting these effects are expected to be of the order 1% of the decay rate. Due to the introduction of QED effects, we must calculate the full QCD + QED path integral on the lattice and this introduces a number of complications. In this presentation, I will introduce Lattice QCD+QED as a calculation method for flavour physics observables and discuss how leptonic decay rates are calculated on the lattice with the inclusion of isospin breaking effects.
Quantum Gravity and the dilaton portal

Alex MitchellLister
(University of Southampton)
Quantum Gravity and the dilaton portal
Alex MitchellLister
(University of Southampton)
12:15 PM  12:35 PM
Room: CM107
In this brief talk I discuss two aspects of a novel approach to quantum gravity, the first of these is the construction of evanescent operators of the dilaton which provides an initial direction to finding solutions to the inherent problems of nonrenormalizability of quantum gravity. The second is the use of the BatalinVilkovisky antifield technique and how this can be used with cohomological techniques to restrict the terms in our action. Following this, and time permitting, a brief review of present and future work will be discussed.