BtSM Event Announcements

  • Thread starter Doc Al
  • Start date
  • #1
Doc Al
Mentor
44,913
1,171

Main Question or Discussion Point

This sticky is for announcements of pertinent scientific events, such as conferences, seminars, or public talks. This sticky may also be used to inform readers about papers, reviews, books, or conference talks involving forum members.
 
Last edited:
  • Like
Likes makemoneyu

Answers and Replies

  • #2
Hans de Vries
Science Advisor
Gold Member
1,089
23
Congratulations Richard Obousy

Congratulations to long time PF member https://www.physicsforums.com/member.php?u=7733" on
the arXiv. Richard is a graduate student with Gerald Cleaver.

Radius Destabilization in Five Dimensional Orbifolds from Lorentz Violating Fields
Authors: https://www.physicsforums.com/member.php?u=7733"
Abstract: One of the challenges in connecting higher dimensional theories to cosmology is stabilization of the moduli fields. We investigate the role of a Lorentz violating vector field in the context of stabilization. Specifically, we compute the one loop Casimir energy in Randall-Sundrum 5-dimensional (non-supersymmetric) S^1/ Z_2 orbifolds resulting from the interaction of a real scalar field with periodic boundary conditions with a Lorentz violating vector field. We find that the result is an enhanced attractive Casimir force. Hence, for stability, positive contributions to the Casimir force from branes and additional fields would be required to counter the destabilizing, attractive effect of Lorentz violating fields.


Regards, Hans
 
Last edited by a moderator:
  • Like
Likes makemoneyu
  • #3
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Carlo Rovelli just presented some joint work he did with Francesca Vidotto.
Stepping out of Homogeneity in Loop Quantum Cosmology
http://relativity.phys.lsu.edu/ilqgs/rovelli042208.pdf
francesca joined PF in 2005 and has contributed to BtSM.
https://www.physicsforums.com/search.php?searchid=1108811 [Broken]

The talk was 22 April at the ILQGS (an international conference-call seminar) and is available online.
 
Last edited by a moderator:
  • Like
Likes makemoneyu
  • #4
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
QG conference

http://www.maths.nottingham.ac.uk/r...ntum_geometry_and_quantum_gravity_conference/
QG2 2008 Quantum Geometry and Quantum Gravity Conference
Monday June 30th - Friday July 4th 2008
University of Nottingham, UK
Topics:

*Quantum gravity, including loop quantum gravity, spin foam models, 1+1 and 2+1 quantum gravity, perturbative and discrete approaches. Quantum cosmology.


*Quantum geometry, including physical aspects of non-commutative geometry, quantum groups and quantum topology. Non-commutative field theory and deformed special relativity.

Some of the speakers and talks are already listed at the site.
 
Last edited:
  • #5
334
1
Thanks for the congrats Hans!
Its nice to know you guys keep an eye out for PF members new papers.

Richard
 
  • #6
Gokul43201
Staff Emeritus
Science Advisor
Gold Member
7,051
17
String Phenomenology 2008
May 28 - June 1, 2008


Introduction

This year’s String Phenomenology Conference will take place at the University of Pennsylvania, Philadelphia, PA, from Wednesday, May 28 to Sunday, June 1, 2008. The Conference Venue will be the David Rittenhouse Laboratory, rooms A5, A6, A7 & A8. This is the seventh in the annual series of SP Conferences. There will also be a banquet, for the conference participants, on Friday, May 30, in Bodek Lounge, Houston Hall, at 6:30 PM (see registration).
This is the last week for registration.

http://www.math.upenn.edu/StringPhenom2008/ [Broken]
 
Last edited by a moderator:
  • #7
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Oporto meeting on Approaches to Quantum Gravity--what can we learn?

http://faraday.fc.up.pt/omgtp2008/
Every year there is the Oporto Meeting on Geometry Topology and Physics. This year the theme of the Oporto Meeting will be Approaches to Quantum Gravity.

There will be four main speakers. We can see the titles of their talks and find (more or less) corresponding papers that they have already posted on arxiv. So we can easily find current research papers which Oporto, in effect, puts the spotlight on. Let's see what we can learn by studying the program of four main talks.

Recall that QG is not a fixed academic subject but is dynamically changing. How experts and active researchers in the field see it can change considerably over the course of a few years, or even from year to year.

MAIN SPEAKERS
The main speakers will each give a minicourse of three one-hour lectures.

Ali CHAMSEDDINE (American U. of Beirut & IHES, Bures-sur-Yvette)
Classification of discrete noncommutative geometries and the uniqueness of the standard model

Steven GIDDINGS (University of California, Santa Barbara)
Probing nonperturbative gravity: black holes, locality, and cosmology

Renate LOLL (Utrecht University)
Quantum Gravity from Causal Dynamical Triangulations

Thomas THIEMANN (Max Planck Institute for Gravitational Physics, Golm)
Loop Quantum Gravity
 
Last edited:
  • #8
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Ali Chamseddine, Classification of discrete noncommutative geometries and the uniqueness of the standard model

Abstract:

Assuming that space-time is a product of a continuous four-dimensional manifold times a discrete space F, we classify the irreducible geometries F consistent with imposing reality and chiral conditions on spinors. Remarkably we find that the noncommutative geometry of the standard model results almost uniquely, with all the necessary details. In particular we prove that the number of fermions per generation is 16, the square of an even integer. The spectral action of this geometry is constructed, and the model is analyzed.
==================================

Steven Giddings, Probing nonperturbative gravity: black holes, locality, and cosmology

Abstract:

I will describe conflict of general physical principles in the non-perturbative regime of quantum gravity, particularly involving black holes. Notably, this conflict suggests reexamination of the principle of locality. If there is time, some related aspects of cosmology will be discussed.
====================================

Renate Loll, Quantum Gravity from Causal Dynamical Triangulations

Abstract:

I discuss motivation, implementation and results of the nonperturbative approach to quantum gravity based on Causal Dynamical Triangulations, including the recent reconstruction of de Sitter space from quantum fluctuations.
======================================

Thomas Thiemann, Loop Quantum Gravity

Abstract:

We give an introduction to the main concepts of Loop Quantum Gravity
===============endquote=======================

These are the abstracts. Each of the four main speakers will give a three-hour mini-course on these topics spread out over the several days of the conference (10-13 July). Let's see what papers we can find that tie in here and what we can learn from them.
 
  • #9
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Giddings is the String thinker in the lineup. Here is the recent paper of his that matches the topic:
http://arxiv.org/abs/0705.2197
Black holes, information, and locality
Steven B. Giddings
(last revised 5 Feb 2008)

"Thirty years of a deepening information paradox suggest the need to revise our basic physical framework. Multiple indicators point toward reassessment of the principle of locality: lack of a precise definition in quantum gravity, behavior of high-energy scattering, hints from strings and AdS/CFT, conundrums of quantum cosmology, and finally lack of good alternative resolutions of the paradox. A plausible conjecture states that the non-perturbative dynamics of gravity is unitary but nonlocal. String theory may directly address these issues but so far important aspects remain elusive. If this viewpoint is correct, critical questions are to understand the 'correspondence' limit where nonlocal physics reduces to local quantum field theory, and beyond, to unveil principles of an underlying nonlocal theory."
=============================

Loll mentioned that when they integrate what is essentially a Feynman path integral thru the space of geometries, they get de Sitter space. That is, a maximally symmetric spacetime with positive cosmological constant. This corresponds to a recent paper:

http://arxiv.org/abs/0712.2485
Planckian Birth of the Quantum de Sitter Universe
Authors: J. Ambjorn, A. Gorlich, J. Jurkiewicz, R. Loll
4 pages, 3 figures
(Submitted on 17 Dec 2007)

"We show that the quantum universe emerging from a nonperturbative, Lorentzian sum-over-geometries can be described with high accuracy by a four-dimensional de Sitter spacetime. By a scaling analysis involving Newton's constant, we establish that the linear size of the quantum universes under study is in between 17 and 28 Planck lengths. Somewhat surprisingly, the measured quantum fluctuations around the de Sitter universe in this regime are to good approximation still describable semiclassically. The numerical evidence presented comes from a regularization of quantum gravity in terms of causal dynamical triangulations."
==========================

I think I will discuss some of the physics in THIS paper, as a sample of what will be highlighted at Oporto this summer. That seems like one way to learn something from the Oporto Meeting's program, or to let it teach us something. If anyone else wants to discuss some of the other content, that's fine too.
 
  • #10
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Strings '08 speaker list

Strings '08 will be at CERN August 18-23
The speaker list is here:
http://ph-dep-th.web.cern.ch/ph-dep-th/content2/workshops/strings2008/?site=content/talks.html [Broken]
All the talks are plenary session and all speakers are invited (there are no parallel sessions with volunteered talks).
There are 8 one-hour summary overview talks listed and about 30 half-hour research talks. It is an unusually compact format, for what is usually a large well-attended conference.
Here is what the welcome page at the webite has to say:
"Welcome to Strings 2008, which will be held at CERN in the year during which the LHC starts up. ... For more details about the conference, see the links on the left.

The lectures will take place in the CERN main auditorium. All participants must register in order to get admitted to the lecture hall. There will be about 40 talks, most of which are summaries of 30 minutes each, but each day there will also be one or two more comprehensive, one hour review talks. The speakers will be nominated by the committee, and self-applications are discouraged. The precise schedule will be announced on this web site shortly before the meeting. "
 
Last edited by a moderator:
  • #11
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Emergent gravity at MIT in August

http://www.rle.mit.edu/emergent/participants.htm

a gathering of new approaches we've been hearing a lot about.
celebrity list includes

Renate Loll
Xiao-gang Wen
Lee Smolin
Seth Lloyd
Song He (the guy at Beijing working on braid-matter with Yidun Wan at Perimeter)

25-29 August, at the MIT Center for Theoretical Physics, registration is free
 
Last edited:
  • #12
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Congratulations Francesca!

PF member Francesca is in Rovelli's group at Marseille. The homogeneity assumption needs to be relaxed in LQC, to bring LQC closer to the full LQG theory. They found a way to do it partway in a gradual fashion. Recently Rovelli delivered an online seminar talk about this at ILQGS.

http://arxiv.org/abs/0805.4585
Stepping out of Homogeneity in Loop Quantum Cosmology
Carlo Rovelli, Francesca Vidotto
16 pages
(Submitted on 29 May 2008)

"We explore the extension of quantum cosmology outside the homogeneous approximation, using the formalism of loop quantum gravity..."
 
  • #13
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
QG school and workshop at Sussex in September

The main event is a 3-day workshop 17-19 September 2008
http://www.ippp.dur.ac.uk/Workshops/08/CLAQG
This will be held at Sussex and admission is free. It will be preceded by a 2-day school
15-16 September aimed at getting graduate students and postdocs entering the field prepared with the basics so they can get maximum benefit from the workshop.
http://www.ippp.dur.ac.uk/Workshops/08/NPMQFT

The workshop is called
Workshop on Continuum and Lattice Approaches to Quantum Gravity (CLAQG)
and the main speakers will be

* Jan Ambjorn (NBI Copenhagen)
* Damiano Anselmi (U Pisa)
* Emil Bjerrum-Bohr (IAS Princeton)
* Daniel Litim (U Sussex)
* Renate Loll (U Utrecht)
* Max Niedermaier (U Tours)
* Roberto Percacci (SISSA Trieste)
* Martin Reuter (U Mainz)
* Thomas Thiemann (AEI Golm and Perimeter Institute)

It is noteworthy that TRIANGULATIONS or lattice QG and also ASYMPTOTIC SAFETY QG are each represented by several speakers. Jan Ambjorn and Renate Loll are both speaking about the triangulations work. Roberto Percacci, Max Niedermaier, and Martin Reuter, pursuing the asymptotic safety approach, are there as well.

In both these two approaches they find that the quantum spacetime continuum does not have a fixed dimensionality, but that a 4D smooth continuum emerges at larger scale while at smaller (trans-Planck) scale the dimension goes down and the spacetime is rougher.

The two approaches are in a sense natural allies because they confirm each other. They find similar mathematical reality coming from different directions. This mutual support has been made explicit in numerous papers and at last years Loops 07 conference.

It looks to me as if this Sussex school and workshop is in effect recruiting brainpower into the field. There is a lot of work to be done in this field and they can use a lot of grad students and postdocs.

The two-day preparatory school before the workshop is called
School on Non-Perturbative Methods in Quantum Field Theory (NPMQFT)

* Basics of the non-perturbative renormalisation group (D. Litim, U Sussex)
* Basics of the RG for QCD and confinement (J.M. Pawlowski, U Heidelberg)
* Basics of QCD on the lattice (O. Philipsen, U Muenster)
* Basics of asymptotic safety for gravity (M. Niedermaier, U Tours)
* Basics of the RG for quantum gravity (M. Reuter, U Mainz)
* Basics of lattice quantum gravity I (R. Loll, U Utrecht)
* Basics of lattice quantum gravity II (J. Barrett, U Nottingham) (t.b.c.)

School starts 9AM Monday morning 15 September and Workshop ends 6PM Friday evening 19 September.
Notice that the participation of John Barrett is "to be confirmed".
Notice that Renate Loll is calling the causal dynamical triangulations (CDT) approach by the name "lattice quantum gravity".
This has the acronym LQG causing a mildly stimulating subliminal shock. In a nonperturbative lattice approach to spacetime geometry, the lattice is not a fixed regular lattice, but is, in effect, a random dynamical triangulation. Evidently one can call triangulation QG by the name lattice QG but making clear that it is a nonperturbative and background independent approach.
Anyway that is the list of topics to be covered in the school
 
Last edited:
  • #14
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785


The first week of September there will be something called
INTERNATIONAL SCHOOL OF SUBNUCLEAR PHYSICS
46th Course: Predicted and Totally Unexpected in the Energy Frontier Opened by LHC
Directors: G. 't HOOFT – A. ZICHICHI
29 August – 7 September 2008

and the interesting thing---why I mention it, and ask if anyone has more information---is the quantum gravity angle. Apparently Renate Loll is lecturing at the school.
Loll does simplicial quantum geometry. Her group at Utrecht is on a roll and has remarkable new results---the emergence of a smooth de Sitter universe from chaotic quantum ground, for example, estimates the size of quantum fluctuations in geometry at various scales.

So how does that fit in with the theme of "Totally Unexpected at the LHC Frontier"?

Here's a link
http://www.ccsem.infn.it/
Here's Loll's page mentioning the School of Subnuclear Physics in September at Erice, Sicily
http://www.phys.uu.nl/~loll/Web/seminars/seminars.html

Wow! I just saw the poster for the school. It is worth downloading. You can get it from the ccsem link I just gave by clicking on posters and selecting the Subnuclear Physics one.
The poster has a list of lectures on hot theory topics.
't Hooft on Crystalline Gravity
Lee Smolin on Loop Quantum Gravity
John Schwarz on Superstring/M
Renate Loll on Dynamical Triangulations Gravity
S. Ferrara on SUSY
Z. Bern on SUGRA

It is pretty select blue chip company. Leonard Susskind was invited but not to lecture (they already have Superstring represented by John Schwarz). The line-up gives an up-to-date perspective on what the organizers consider hot theory topics as we approach LHC startup.

Besides the theory lectures, they have talks by experimentalists on projected signals at LHC. It looks like it'll be a grand school! Maybe some people we know will be able to attend. Part of the stated aim of the Erice school is to encourage and inspire young physicists so they appear to have places and support for a substantial number. We'll see.
 
Last edited:
  • #16
MTd2
Gold Member
2,028
25
John's nice exposion o Loll's gravity on his blog!

http://golem.ph.utexas.edu/category/2008/07/causality_in_discrete_models_o.htm [Broken]

The initial post is given by a guest, Gavin Wraith. Later John posts some information about it and gives some of his ideas about that approach.

For example, he also tries to link Loll's gravity with spin foams.

http://math.ucr.edu/home/baez/loops05/loops05.pdf

He is also asking question and more ideas there.

I think Marcus must go there do something.
 
Last edited by a moderator:
  • #17
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785


http://golem.ph.utexas.edu/category/2008/07/causality_in_discrete_models_o.htm [Broken]

The initial post is given by a guest, Gavin Wraith. Later John posts some information about it and gives some of his ideas about that approach.

For example, he also tries to link Loll's gravity with spin foams.

http://math.ucr.edu/home/baez/loops05/loops05.pdf

He is also asking question and more ideas there.

I think Marcus must go there do something.
MTd2, thanks for posting this. The conversation at n-category cafe is quite interesting. I think a letter may be missing from your link. I couldn't get it to work but this works for me:
http://golem.ph.utexas.edu/category/2008/07/causality_in_discrete_models_o.html
 
Last edited by a moderator:
  • #18
21
0


Frank Wilczek's interview, titled "What's Reality", can be listened to or downloaded at http://www.wnyc.org/shows/lopate/episodes/2008/09/15 [Broken]
 
Last edited by a moderator:
  • #19
MTd2
Gold Member
2,028
25


Garrett will organize a small workshop.
 
  • #20
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785


Strings 2009 conference will be held in Rome, 22-26 July
http://strings2009.roma2.infn.it/home.html
The plan is all the talks will be invited plenary. There will be no contributed talks in parallel sessions. This is the same plan as was followed by Strings 2008 at CERN in August.
 
  • #21
Fra
3,097
144


From the thread "String Field Theory and Background Independence?"
But may it's true that "all roads lead to Rome". The question is just which roads are the fastest, through the string bush, or some other way.
Strings 2009 conference will be held in Rome, 22-26 July
http://strings2009.roma2.infn.it/home.html
The plan is all the talks will be invited plenary. There will be no contributed talks in parallel sessions. This is the same plan as was followed by Strings 2008 at CERN in August.
I guess I didn't have a clue how right I was :biggrin:

/Fredrik
 
  • #22
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785
Loops '09

First Announcement
International Conference on Quantum Gravity: Loops '09

The annual international conference on non-perturbative/background independent
quantum gravity will take place from 2 to 8 August 2009 at Beijing Normal
University in China. It stands in the tradition of Loops '04 in Marseille, Loops
'05 in Potsdam and Loops '07 in Morelia, but is more concentrated on the issues
and approaches closely related to loop quantum gravity. The main topics include:

* Loop quantum gravity
* Loop quantum cosmology and other symmetric models
* Spin foams and their low energy ramifications
* Fundamental questions of quantum gravity
* Cosmology related to quantum gravity
* Phenomenology of quantum gravity.

International Scientific Advisory Committee:
ASHTEKAR Abhay (Penn State Univ, USA)
BARRETT John (Univ of Nottingham, UK)
CORICHI Alejandro (Universidad Nacional Autonona de Mexico, Mexico)
LEWANDOWSKI Jerzy (Univ of Warsaw, Poland)
MENA MARUGAN Guillermo (Instituto de Estructura de la Materia, CSIC, Spain)
PULLIN Jorge (Louisiana State Univ, USA)
RIVASSEAU Vincent (Univ of Paris-Sud XI, France)
ROVELLI Carlo (Univ of Mediterranee, France)
SMOLIN Lee (Perimeter Inst for Theor Phys, Canada)
THIEMANN Thomas (Albert-Einstein Inst, Germany).

Local Scientific Advisory Committee:
DUAN Yi-Shi (Univ of Lanzhou)
GUO Han-Ying (Inst of Theor Phys, CAS)
LI Xin-Zhou (Shanghai Normal Univ)
LIANG Canbin (Beijing Normal Univ)
LIU Liao (Beijing Normal Univ)
LU Tan (Purple Mountain Observatory, CAS)
WANG Shi-Kun (Acad of Math and Syst Science, CAS)
WU Yue-Liang (Inst of Theor Phys, CAS)
ZHANG Yuan-Zhong (Inst of Theor Phys, CAS)
ZHAO Zheng (Beijing Normal Univ)

Instructions for online registration will be given in the second announcement.
 
  • #23
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785


http://www.uv.es/bhlqg/

A workshop in March 2009--at University of Valencia.
Black Holes and LQG
The list of talks has not been posted yet.
The scientific committee (responsible for putting the program together) are:
Abhay Ashtekar (IGC-PSU, USA)
Fernando Barbero (IEM-CSIC, Spain)
Alejandro Corichi (IM-UNAM, Mexico)
Jerzy Lewandowski (Universytet Warszawski, Poland)
Guillermo Mena (IEM-CSIC, Spain)
Hanno Sahlmann (Universität Karlsruhe, Germany)
Thomas Thiemann (AEI, Germany)
Madhavan Varadarajan (RRI, India)

<thanks to Christine Dantas for this item>
 
Last edited:
  • #24
marcus
Science Advisor
Gold Member
Dearly Missed
24,738
785


http://adm-50.physics.tamu.edu/speakers.php
November 7 and 8.
Conference at Texas A&M celebrating the 50-anniversary of the ADM reformulation of General Relativity by Arnowitt Deser Misner.

Speakers list:
Abhay Ashtekar
Zvi Bern
Steven Carlip
Michael Duff
James Hartle
Christopher Pope
Jorge Pullin
Bernard Schutz
Kellogg Stelle
Nicholas Suntzeff
Robert Wald
Rainer Weiss
Richard Woodard
 

Related Threads on BtSM Event Announcements

  • Last Post
Replies
3
Views
4K
  • Last Post
Replies
1
Views
914
Replies
0
Views
2K
Replies
2
Views
1K
Replies
42
Views
9K
Replies
2
Views
4K
  • Last Post
Replies
9
Views
4K
  • Last Post
Replies
6
Views
2K
  • Last Post
Replies
2
Views
2K
  • Last Post
Replies
3
Views
2K
Top