2017-08 – Resolution of singularities and geometric proofs of the Lojasiewicz inequalities

DIAS-STP-17-08

Resolution of singularities and geometric proofs of the Lojasiewicz inequalities

P. Feehan

This preprint is available on Arxiv.org

This preprint is available for download :

Details provided:

  • Date of publication : 31/08/17

To obtain copies of any of the preprints in the archives, please contact us and specify the preprint number(s), author(s), title(s) and number of copies wanted.

Modern Physics Letters A – Samuel Kováčik (STP) Published Paper

Title
Author
Samuel Kováčik – School of Theoretical Physics, DIAS
Abstract

We study a black hole with a blurred mass density instead of a singular one, which is caused by the noncommutativity of three-space. Depending on its mass, such object has either none, one or two event horizons. It possesses properties, which become important on a microscopic scale, in particular, the Hawking temperature does not increase indefinitely as the mass goes to zero, but vanishes instead. Such frozen and extremely dense pieces of matter are good dark matter candidates.

Thursday 6th July: STP Seminar – “Quantum engineering using magnetic fields: Quantum Magnetomechanics”

Title: Quantum engineering using magnetic fields: Quantum Magnetomechanics

Speaker: Jason Twamley (Macquarie University, Sydney)

Abstract: Optomechanics – the control and manipulation of mesocopic objects towards the quantum regime, has attracted much attention. The use of light however, brings with it several problems, scattering noise being just one. In this talk we introduce a new approach to control the quantum motion of mescoscopic objects using magnetic fields. We describe our proposal to levitate and cool superconducting objects using magnetic fields and superconducting quantum circuits, how such levitated objects can be used for high precision gravimetry, specific experimental designs for ultra-strong and deep strong coupling using magnetomechanics and how one can engineer spin squeezing and spin Cats using magnetomechanics.

Time: Thursday 6th July 2017, 2.30pm.

Place: Seminar Room, School of Celtic Studies, DIAS, 10 Burlington Road, Dublin 4.

Graham Kells Paper: Physical Review B – Editor’s Suggestion

‘Parafermionic clock models and quantum resonance’:

A paper co-authored by Dr Graham Kells (STP) has been noted as ‘Editor’s Suggestion’ in the current issue of Physical Review B.

DIAS Research Forum 2017 – Wednesday 17th May

 

An inter-disciplinary research forum has been scheduled for Wednesday 17 May 2017, 3-5pm at Burlington Road. The forum is intended to be an informal event that provides post-doctoral scholars and PhD students with the opportunity to share and discuss their current research with scholars and staff from across the three schools of DIAS.

There will be no main speakers at the event. Instead, participants will be assigned a space where they can share and discuss their research interests. Participants are encouraged to present a poster which visually complements their research, and allows them to explain what they do to all DIAS staff. In instances where a poster presentation is not appropriate, participants should feel free to develop an alternative approach.

The forum presents a great opportunity for scholars to sharpen their academic presentation and public outreach skills in an informal setting, while also getting to know colleagues from across the Institute.

The organisers strongly encourage scholars from all three schools to participate in the forum. A coordinator from each section will liaise with participants regarding their presentations.

Participants are asked to register here prior to Friday 12 May.

Section Coordinators:
Celtic Studies - Eibhlín Nic Dhonncha eibhlin@celt.dias.ie
CP, Astrophysics - Eileen Flood eflood@cp.dias.ie & Anne Grace ag@cp.dias.ie
CP, Geophysics - Clare Horan choran@cp.dias.ie
Theoretical Physics - George Rogers grogers@stp.dias.ie
Please contact your section coordinator with any queries.

All DIAS staff are welcome to attend.

 

Monday 27th March: STP Seminar – “Yang-Baxter sigma-models, conformal twists & noncommutative Yang-Mills”

Title: Yang-Baxter sigma-models, conformal twists & noncommutative Yang-Mills

Speaker: Eoin Ó Colgáin (University of Surrey)

Abstract: The Yang-Baxter σ-model is a systematic way to generate integrable deformations of AdS5×S5. We recast the deformations as seen by open strings, where the metric is undeformed AdS5×S5 with constant string coupling, and all information about the deformation is encoded in the noncommutative (NC) parameter Θ. We identify the deformations of AdS5 as twists of the conformal algebra, thus explaining the noncommutativity. We show that the unimodularity conditon on r-matrices for supergravity solutions translates into Θ being divergence-free. Integrability of the σ-model for unimodular r-matrices implies the existence and planar integrability of the dual NC gauge theory.

Time: Monday 27th March 2017, 3.00pm.

Place: Lecture Room, School of Theoretical Physics, DIAS, 10 Burlington Road, Dublin 4.

Tuesday 14th March: STP Seminar – “Gaussian free fields at the integer quantum Hall plateau transition”

Title: Gaussian free fields at the integer quantum Hall plateau transition.

Speaker: Roberto Bondesan (Oxford).

Abstract: The transition between Hall conductance plateaus of the integer quantum Hall effect stands out as a possible paradigm for quantum phase transitions of Anderson-localization type. Yet, in spite of numerous efforts and a renewed interest coming from the expanding field of topological phases, understanding this transition has so far defied an analytical solution by the methods of conformal field theory and/or the theory of integrable systems.

In this talk I will review our approach based on a supersymmetric vertex model and the construction of conformal primary fields on the lattice from highest weight vectors of the vertex model in the presence of point contacts. The outcome of the analysis will be an effective free field description of critical wave intensities leading to a parabolic multifractality spectrum.

Time: Tuesday 14th March 2017, 2.30pm.

Place: Lecture Room, School of Theoretical Physics, DIAS, 10 Burlington Road, Dublin 4.

Wednesday 22nd February: DIAS General Interest Seminar – ‘Recent Trends in the Philosophy of Science’

Title: Recent Trends in the Philosophy of Science

Speaker: Dr Finnur Dellsén (University College Dublin)

Abstract: Many working scientists are familiar with Karl Popper’s vision of science as the concerted effort to falsify extent theories and replace them with new theories that make bold predictions about unobserved events. Popper’s ideas have been less influential among philosophers of science, due to a number of arguably devastating problems with his underlying approach. This talk will survey some of the more influential criticisms of Popper, and go on to discuss two other influential ways of thinking about science, viz. Thomas Kuhn’s idea of ‘paradigms’ as the basic unit of real scientific change, and the ‘Bayesian’ idea of scientific confirmation as grounded in subjective probability-assignments.

Time: Wednesday 22nd February 2017, 4.00pm.

Place: Lecture Room, School of Theoretical Physics, DIAS, 10 Burlington Road, Dublin 4.

Friday 27th January: STP Seminar – “Evolution of Open Systems and Dynamical Semigroups”

Title: Evolution of Open Systems and Dynamical Semigroups

Speaker: Valentin A. Zagrebnov (Institut de Mathématiques de Marseille)

Abstract: We consider dynamical semigroups for unbounded Kossakowski-Lindblad-Davies generators corresponding to evolution of open systems. For this evolution we prove the existence of uniquely determined minimal trace-preserving strongly continuous dynamical semigroups on the space of states constructed by a regularisation à la Kato. We illustrate these results by a simplest example of the open quantum oscillator. The corresponding dual W*-dynamical system is unital quasi-free and (completely) positive automorphism of the Weyl CCR-algebra.

Time: Friday 27th January 2017, 2.00pm.

Place: Lecture Room, School of Theoretical Physics, DIAS, 10 Burlington Road, Dublin 4.

Thursday 8th December: STP Seminar – “Einstein–Maxwell–Anti-de-Sitter solitons and black holes”

Title: Einstein–Maxwell–Anti-de-Sitter solitons and black holes

Speaker: Eugen Radu (Aveiro University)

Abstract: We consider a new class of solutions in Einstein-Maxwell theory with a negative cosmological constant, that approach asymptotically a globally Anti-de-Sitter (AdS) background in four spacetime dimensions. There are no analogue objects to these solutions in asymptotically flat spacetime and their existence can be traced back to the “box”-like behaviour of the AdS spacetime. Both solitons and black holes are discussed. In the latter case, we report on static solutions that have no continuous spatial symmetries. These black holes have a smooth, topologically spherical horizon, but without isometries.

Time: Thursday 8th December 2016, 2.00pm.

Place: Lecture Room, School of Theoretical Physics, DIAS, 10 Burlington Road, Dublin 4.