International Loop Quantum Gravity Seminar

This is a seminar on research that takes place every Tuesday at 9am (US Central Time). Audio is distributed via telephone. Slides of the talks are posted in advance here. Talks are recorded and the audio posted here. Among the groups that participate live are PennState, Perimeter Institute, Marseille, AEI-Potsdam, Utrecht, UNAM-Mexico, FUW-Poland, CSIC-Madrid, UDELAR, Uruguay, UWO-Canada, UNB-Canada, Umass Dartmouth, Hamilton College, IISER Kolkata-India, Florida Atlantic University, University of Minho, Bard College, UNAB-Chile and LSU. Unfortunately, the phone bridge we have has a limited number of lines so we cannot open live participation to everyone. If your group wishes to participate, please write to pullin at lsu.edu. Locally at LSU, we listen to the talks in 241 Nicholson Hall. You are welcome to join the mailing list. 

Past Seminar Schedules
Fall 06, Spring 07, Fall 07, Spring 08, Fall 08, Spring 09, Fall 09, Spring 10, Fall 10, Spring 11, Fall 11, Spring 12, Fall 12, Spring 13, Fall 13 Spring 14.

Current Seminar Schedule (Fall 2014)

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Visit The loop quantum gravity portal for information on books, conferences, talks and more.!


Upcoming talk:


Tuesday, Oct 28th
Jerzy Lewandowski, Warszaw
Title: New applications for LQG

Past Talks


Tuesday, Oct 14th
Carlo Rovelli, Marseille
Title: White holes
PDF of the talk (1.3Mb)
Audio [.wav 41MB]
Tuesday, September 30th
Brajesh Gupt, PennState
Title: Phenomenological consequences of quantum geometries in LQC
PDF of the talk (1.9Mb)
Audio [.wav 24MB]

2014


Tuesday, September 16th
Wolfgang Wieland, PennState
Title: Covariant loop quantum gravity: Its classical action, phase space and gauge symmetries
PDF of the talk (1Mb)
Audio [.wav 36MB]
Tuesday, September 2nd
Javier Olmedo, LSU
Title: Casimir effect on a quantum geometry
PDF of the talk (182k)
Audio [.wav 20MB]
Tuesday, May 13th
Jorge Pullin, LSU
Title: Hawking radiation in loop quantum gravity
PDF of the talk (600k)
Audio [.wav 25MB]
Tuesday, April 29th
Ivan Agullo, Aurelien Barrau, Guillermo Mena
Title: LQC and the very early universe
PDF of the talk - Agullo (1M)
PDF of the talk - Barrau (1M)
PDF of the talk - Mena(3M)
Audio [.wav 41MB]
Tuesday, April 15th
Antonia Zipfel, Warszaw
Title: Linking canonical and covariant LQG
PDF of the talk (0.5M) Audio [.wav 30MB]
Tuesday, April 1st
Laurent Freidel, Perimeter Institute
Title: Continuum limit and renormalization
PDF of the talk (10M) Audio [.wav 49MB]
Tuesday, Mar 18th
Max Dohse, UNAM-Morelia
Title: S-matrices for General Boundary QFT on Anti de Sitter spacetime
PDF of the talk (4.6M) Audio [.wav 36MB]
Tuesday, Mar 4th
Marc Geiller, Penn State and Simone Speziale, Marseille
Title: Discussion on simplicity constraints in spin foam models
PDF of the talk (400K) Audio [.wav 31MB]
Tuesday, Feb 18th
Sebastian Steinhaus, Perimeter Institute
Title: Quantum group spin nets: refinement limit and relation to spin foams
PDF of the talk (620K) Audio [.wav 37MB]
Tuesday, Feb 4th
Bianca Dittrich, Perimeter Institute
Title: A new vacuum for loop quantum gravity
PDF of the talk (11M) Audio [.wav 70MB]
Tuesday, Jan. 21st
Pietro Dona, Sissa
Title: Matter matters in asymptotically safe quantum gravity
PDF of the talk (213K) Audio [.wav 34MB] Audio [.aif 3.4MB]

2013


Tuesday, Dec. 10th
Saeed Rastgoo, UNAM Morelia
Title: Towards the resolution of the CGHS singularity in LQG
PDF of the talk (380K) Audio [.wav 24MB] Audio [.aif 2.4MB]

Tuesday, Nov. 26th
Johannes Thürigen, Albert Einstein Institute
Title: Spectral dimension of quantum geometries
PDF of the talk (1MB) Audio [.wav 39MB] Audio [.aif 4.1MB]


Tuesday, Nov. 12th
Tim Koslowski, Univ. New Brunswick
Title: What can we learn from shape dynamics?
PDF of the talk (500k) Audio [.wav 39MB] Audio [.aif 4.1MB]

Tuesday, Oct. 29th
Asieh Karami, UNAM Morelia
Title: Bianchi IX LQC: Quantization ambiguity and effective description
PDF of the talk (600k) Audio [.wav 15MB] Audio [.aif 1.5MB]

Tuesday, Oct. 15th
Derek Wise, FAU Erlangen
Title: Holographic special relativity: observer space from conformal geometry
PDF of the talk (600k) Audio [.wav 38MB] Audio [.aif 4MB]

Tuesday, Oct. 1st
Norbert Bodendorfer, PennState
Title: Black hole entropy from LQG: higher dimensions and generalized theories
PDF of the talk (300k) Audio [.wav 38MB] Audio [.aif 4MB]
Tuesday, Sept. 17th.
Hal Haggard, CPT Marseille
Title: Thermality of spherical causal domains & the entanglement spectrum
PDF of the talk (7MB) Audio [.wav 33MB] Audio [.aif 4MB]
Tuesday, Sept. 3rd.
Jose Antonio Zapata, UNAM Morelia
Title: Multisymplectic effective General Boundary Field Theory
PDF of the talk (900k) Audio [.wav 35MB] Audio [.aif 4MB]
Tuesday, May 7th.
Yasha Neiman, PennState
Title: The imaginary part of the GR action and the large-spin 4-simplex amplitude
PDF of the talk (300k) Audio [.wav 73MB] Audio [.aif 4MB] Tuesday, Apr. 23rd.

Martin Bojowald, PennState
Title: A loop quantum multiverse?
PDF of the talk (170k) Audio [.wav 43MB] Audio [.aif 4MB]
Tuesday, Apr. 9th
Wolfgang Wieland, CPT Marseille
Title: Hamiltonian spinfoam gravity
PDF of the talk (1.5Mb) Audio [.wav 36MB] Audio [.aif 3MB]

Tuesday, Mar 26th.
Brajesh Gupt, LSU
Title: Bianchi I LQC, Kasner transitions and inflation
PDF of the talk (800k) Audio [.wav 30MB] Audio [.aif 3MB]
Tuesday, Mar 12th.
Emanuele Alesci, Francesco Cianfrani
Title: Quantum reduced loop gravity
PDF of the talk (4Mb) Audio [.wav 29MB] Audio [.aif 3MB]
Tuesday, Feb 26th.
Stephon Alexander
Title: Gravity electroweak unification
PDF of the talk (8Mb) Audio [.wav 32MB] Audio [.aif 4MB]
Tuesday, Feb 12th.
Hal Haggard, CPT Marseille
Title: Dynamical chaos and the volume gap
PDF of the talk (8Mb) Audio [.wav 37MB] Audio [.aif 4MB]
Tuesday, Jan 29th.
Eugenio Bianchi, Perimeter Institute.
Title: Entanglement in loop quantum gravity
PDF of the talk (3Mb) Audio [.wav 81MB] Audio [.aif 4MB]

2012


Tuesday, Nov 27th.
Bianca Dittrich, Perimeter Institute
Title: Coarse graining: towards a cylindrically consistent dynamics
PDF of the talk (14Mb) Audio [.wav 41MB] Audio [.aif 4MB]
Tuesday, Nov 13th.
Simone Speziale, CPT-CNRS Marseille
Title: Twistorial structure of loop quantum gravity transition amplitudes
PDF of the talk (600k) Audio [.wav 32MB] Audio [.aif 3MB]
Tuesday, Oct 30th.
Sylvain Carrozza, Albert Einstein Institute
Title: Renormalization of Tensorial Group Field Theories
PDF of the talk (1.3M) Audio [.wav 45MB], Audio [.aif 4MB].
Tuesday, Oct 16th.
Eugenio Bianchi, Perimeter Institute
Title: Horizon entropy from loop gravity
PDF of the talk (7M) Audio [.wav 42MB], Audio [.aif 4MB].
Tuesday, Oct 2nd.
Derek Wise, FAU Erlangen
Title: Lifting General Relativity to Observer Space
PDF of the talk (700k) Audio [.wav 34MB], Audio [.aif 3MB].
Tuesday, Sept 18th.
Lorenzo Sindoni, Albert Einstein Institute
Title: Flux coherent states
PDF of the talk (2Mb) Audio [.wav 38MB], Audio [.aif 4MB].
Tuesday, Sept 4th.
Frank Hellmann, Albert Einstein Institute
Title: Holonomy Spin Foam Models: Asymptotic Dynamics
PDF of the talk (0.39Mb) Audio [.wav 32MB], Audio [.aif 3MB].
Tuesday, May 8th.
Richard Woodard, University of Florida
Title: Graviton Corrections to Maxwell's Equations
PDF of the talk (0.15Mb) Audio [.wav 24MB], Audio [.aif 2MB].

Tuesday, Apr 24th.
Seabastian Steinhaus, Albert Einstein Institute
Title: Path integral measure and triangulation independence in discrete gravity
PDF of the talk (0.5Mb) Audio [.wav 24MB], Audio [.aif 2MB].

Tuesday, Apr 10th.
Tim Koslowski, Perimeter Institute
Title: Effective Field Theories for Quantum Gravity form Shape Dynamics
PDF of the talk (0.5Mb) Audio [.wav 31MB], Audio [.aif 3MB].

Tuesday, Mar 27th.
Alejandro Perez, Marseille
Title: Black hole entropy in LQG: new insights from a local perspective
PDF of the talk (3.5Mb) Audio [.wav 47MB], Audio [.aif 5MB].

Tuesday, Mar 13th.
Jacobo Diaz-Polo, LSU
Title: Black hole evaporation in LQG
PDF of the talk (2.5Mb) Audio [.wav 38MB], Audio [.aif 4MB]. )

Tuesday, Feb 28th.
Marc Geiller, Univ. Paris
Title: Continuous formulation of the LQG phase space
PDF of the talk (400k)
Audio [.wav 36MB], Audio [.aif 4MB].
Tuesday, Feb 14th.
Claudio Perini, PennState
Title: Classical limit of spin foams on arbitrary tri angulations
PDF of the talk (2MB)
Audio [.wav 40MB], Audio [.aif 4MB].
Tuesday, Jan 31st.
Parampreet Singh, LSU
Title: Physics of Bianchi models in LQC
PDF of the talk (500KB)
Audio [.wav 40MB], Audio [.aif 4MB].

2011


Tuesday, Nov. 29th
Philipp Hoehn, University of Utrecht
Title: A canonical formalism for simplicial gravity
PDF of the talk (700KB)
Audio [.wav 40MB], Audio [.aif 4MB].
Tuesday, Nov. 15th
Jonathan Engle, Florida Atlantic Univesrity
Title: Plebanski sectors of the new spin foam models
PDF of the talk (3.5MB)
Audio [.wav 38MB], Audio [.aif 4MB].
Tuesday, Nov. 1st
Tim Koslowski, Perimeter Institute
Title: Shape dynamics
PDF of the talk (500k)
Audio [.wav 33MB], Audio [.aif 3MB].
Tuesday, Oct. 18th
William Nelson, PennState
Title: Inhomogeneous loop quantum cosmology
PDF of the talk (500k)
Audio [.wav 32MB], Audio [.aif 3MB].
Tuesday, Oct. 4th
Norbert Bodendorfer/Andreas Thurn
Title: An invitation to the new variables with possible applications
PDF of the talk (500k)
Audio [.wav 35MB], Audio [.aif 3MB], Audio [.mp3 40MB high-quality].
Tuesday, Sept. 20th
Jacek Puchta, University of Warszaw
Title: The Feynman diagramatics for the spin foam models
PDF of the talk (3MB)
Audio [.wav 35MB], Audio [.aif 3MB].
Tuesday, May 10th
Daniele Oriti, Albert Einstein Institute
Title: Quantum geometry: its dynamics, symmetries and statistics in the group field theory formalism
PDF of the talk (1.5MB)
Audio [.wav 40MB], Audio [.aif 4MB].
Tuesday, Apr 26th
Razvan Gurau, Perimeter Institute
Title: The 1/N expansion in colored tensor models
PDF of the talk (400k)
Audio [.wav 33MB], Audio [.aif 3MB].
Tuesday, Apr 12th
James Ryan, Albert Einstein Institute
Title: Simplicity constraints and the role of the Immirzi parameter in quantum gravity
PDF of the talk (11MB)
Audio [.wav 19MB], Audio [.aif 2MB].
Tuesday, Mar 29th
Ivan Agullo, PennState
Title: Observational signatures in LQC
PDF of the slides (6MB)
Audio [.wav 36MB], Audio [.aif 3MB].
Tuesday, Mar 15th
Winston Fairbairn, Hamburg University
Title: Quantum deformation of 4d spin foam models
PDF of the slides (300k)
Audio [.wav 36MB], Audio [.aif 3MB].
Tuesday, Mar 1st
Laurent Freidel, Perimeter Institute
Title: The principle of relative locality
PDF of the slides (7MB)
Audio [.wav 40MB], Audio [.aif 4MB].
Tuesday, Feb 15th
Tomasz Pawlowski, University of New Brunswick
Title: Semiclassicality of the loop quantum universe
PDF of the slides (1MB)
Audio [.wav 26MB], Audio [.aif 2MB].
Tuesday, Feb 1st
Francesca Vidotto, Marseille
Title: Spinfoam cosmology
PDF of the slides (3 MB)
Audio [.wav 26MB], Audio [.aif 2MB].
Tuesday, Jan 18th
Gianluca Calcagni, Albert Einstein Institute
Title: Inflationary observables and observational constraints in LQC
PDF of the slides (1.5MB)
Audio [.wav 40MB], Audio [.aif 4MB].
Blog post

2010


Tuesday, Nov 30th
Matteo Smerlak, ENS Lyon
Title: Bubble divergences in state-sum models
PDF of the slides (180k)
Audio [.wav 25MB], Audio [.aif 5MB].

Tuesday, Nov 16th
Madhavan Varadarajan, Raman Research Institute
Title: LQG dynamics: insights from parameterized field theory
PDF of the slides (1.2M)
Audio [.wav 82MB], Audio [.aif 4MB].
Blog post

Tuesday, Nov 2nd
Jerzy Lewandowski, Warszaw
Title: New results: operator spin foams, SL(2,C)
PDF of the slides (766k)

Audio [.wav 42MB], Audio [.aif 4MB].

Tuesday, Oct 26th
Jerzy Lewandowski, Warszaw
Title: LQG with all the degrees of freedom
PDF of the slides (111k) (updated)
PDF of the slides (1MB)
Audio [.wav 33MB], Audio [.aif 3MB].
Tuesday, Oct 19th
Eugenio Bianchi, Marseille
Title: The cosmological constant (non)-problem
PDF of the slides (1MB)
Audio [.wav 33MB], Audio [.aif 3MB].
Tuesday, Sept 21st
Abhay Ashtekar, PennState
Title: Quantum evaporation of 2-d black holes
Blog post
PDF of the slides (500k)
Audio [.wav 45MB], Audio [.aif 4MB].
Tuesday, May 4th
Alejandro Perez, CPT Marseille
Title: Black hole entropy: an SU(2) gauge invariant treatment
PDF of the slides (4MB)
Audio [.wav 36MB], Audio [.aif 4MB].
Tuesday, April 20
Jose Antonio Zapata, UNAM Morelia
Title: Curvature
PDF of the slides (0.5MB)
Audio [.mp3 9MB], Audio [.aif 4MB].
Tuesday, April 6
Forian Conrady, Perimeter Institute

Title: Spin foams with timelike surfaces
PDF of the slides (1MB)
Audio [.wav 29MB],


Tuesday, March 23
Benjamin Bahr, Albert Einstein Institute

Title: Discretisation and diffeomorphisms
PDF of the slides (1.7MB)
Audio [.wav 31MB], Audio [.aif 3MB].


Tuesday, March 9
Fethi Ramazanoglu, Princeton

Title: Information loss in the CGHS model PDF of the slides (1.2MB)
Audio [.wav 41MB], Audio [.aif 4MB].


Tuesday, February 16th
Tomasz Pawlowski, CSIC Madrid

Title: Big bounce and inhomogeneities: a hybrid approach
PDF of the slides (1.5MB)
Audio [.mp3 12MB], Audio [.aif 5MB].


Tuesday, February 2nd
Claudio Perini, Marseille/Rome

Title: Coherent spin networks
PDF of the slides (0.25MB)
Audio [.wav 32MB], Audio [.aif 3MB].


Tuesday, Jan 19th
David Sloan, PennState

Title: Slow roll inflation in LQG
PDF of the slides (0.5MB)
Audio [.mp3 8MB], Audio [.aif 3MB].


2009


Tuesday, Dec 1st
Alok Laddha, Raman Research Institute

Title: Polymer parameterized field theory
PDF of the slides (1.5MB)
Audio [.wav 37MB], Audio [.aif 3MB].


Tuesday, Nov 17th
Frank Hellmann, University of Nottingham

Title: The Asymptotics of 4d Spin Foam Models from SU(2) Asymptotics
PDF of the slides (216k)
Audio [.wav 37MB], Audio [.aif 3MB].


Tuesday, Nov 3rd
Daniele Oriti, Albert Einstein Institute

Title: Group field theory and all that
PDF of the slides (400k)
Audio [.wav 39MB], Audio [.aif 4MB].


Tuesday, October 20th
Jerzy Lewandowski, Warszaw University

Title: Spin foams from loop quantum gravity perspective
PDF of the slides (1.2MB)
Audio [.wav 38MB], Audio [.aif 4MB].


Tuesday, October 6th
Eugenio Bianchi, CPT Marseille

Title: Aharonov-Bohm and loop quantum gravity
PDF of the slides (430k).
Audio [.mp3 5MB]


Tuesday, September 22nd
Richard Woodard, University of Florida

Title: Questions and answers about Perturbative quantum gravity
PDF of the slides (170k).
Audio [.mp3 10MB], Audio [.aif 4MB].


Tuesday, May 5th
Abhay Ashtekar, Laurent Freidel, Carlo Rovelli

Title: Recovering low energy physics: A Discussion
PDF of the slides (4MB).
Audio [.mp3 12MB],


Tuesday, Apr 21st
John Barrett, Nottingham

Title: Asymptotics of spin foam models with an Immirzi parameter
PDF of the slides (128kB).
Audio [.wav 51MB], Audio [.aif 5MB].


Tuesday, Mar 31st
Craig Hogan, Fermilab

Title: Holographic noise
PDF of the slides (12MB).
Audio [.wav 41MB], Audio [.aif 4MB].


Tuesday, Mar 17th
Adam Henderson, PennState

Title: Path integrals in loop quantum cosmology
PDF of the slides (1.7M).
Audio [.wav 32MB], Audio [.aif 3MB].


Tuesday, Mar 3rd
Simone Mercuri, PennState

Title: Interpretation of the Barbero-Immirzi parameter
PDF of the slides (135k).
Audio [.mp3 8MB],


Tuesday, Feb 10th
Jacobo Diaz-Polo, Valencia

Title: Black hole entropy and number theory
PDF [1MB] of the slides
Audio [.wav 30MB], Audio [.aif 3MB]


Tuesday, Jan 13th
Donald Marolf, UC Santa Barbara

Title: Unitarity and holography in gravitational physics
PDF [360k] of the slides
Audio [.mp3 13MB]


2008


Tuesday, Nov 18th
Parampreet Singh, Perimeter Institute

Title: Loop quantum cosmos are never singular
PDF [277k] of the slides
Audio [.wav 36MB] Audio [.wav 2.4MB]


Tuesday, Nov 4th
Jerzy Lewandowski, Warszaw

Title: Physical solutions and relative observables via group averaging: new examples from LQC
PDF [160k] of the slides
Audio [.wav 32MB] Audio [.aif 3MB]


Tuesday, Oct 21st
Lee Smolin, Perimeter Institute

Title: Possibly observable cosmological consequences of quantum gravity
PDF [4.6MB] of the slides
Audio [.wav 41MB] Audio [.aif 4MB]


Tuesday, Oct 21st
Nico Yunes, Princeton

Title: How constant is the Barbero-Immirzi "constant"?
PDF [3.7M] of the slides
Audio [.wav 26MB] Audio [.aif 2MB]



Tuesday, Sept 9th
Daniel Sudarsky, UNAM, Mexico

Title: Could the seeds of cosmic structure be the first evidence of a Quantum Gravity related phenomena?
PDF [1.8M] of the slides
Audio [.wav 36MB] Audio [.aif 3.8MB]


Tuesday, May 6th
Jerzy Lewandowski, Warszaw

Title: LQC: unfrequently asked questions
PDF [85K] of the slides
Audio [.mp3 6MB]


Tuesday, April 22nd
Carlo Rovelli, Marseille

Title: Stepping out of Homogeneity in Loop Quantum Cosmology
PDF [122k] of the slides
Audio [.mp3 10MB]


Tuesday, April 8th
Laurent Freidel, Perimeter Institute

Title: Quantum gravity perspective on AdS/CFT
PDF [10M] of the slides
Audio [.aif 1MB] Audio [.mp3 89MB, complete]


Tuesday, Mar 25th
Kristina Giesel, Albert Einstein Institute

Title: Manifestly gauge invariant relativistic pertrubation theory
PDF [1.3M] of the slides
Audio [.aif 3MB] Audio [.wav 34MB, complete]


Tuesday, Feb 19th
Victor Taveras, PennState

Title: Improved effective equations in loop quantum cosmology
PDF [380k] of the slides
Audio [.mp3 7MB] of the slides


Tuesday, Feb 5th
Kirill Krasnov, University of Nottingham

Title: Self Dual Gravity
PDF [177k] of the slides
Audio [.mp3 10MB]


Tuesday, Jan 22nd
Madhavan Varadarajan, Raman Research Institute

Title: Quantum gravity and the information loss problem
PDF [1.5M] of the slides
Audio [.aif 4MB] Audio [.mp3 10MB, complete]


2007


Tuesday, Nov 27th
Kevin Vandersloot, Portsmouth

Title: Schwarzschild interior with loop quantum effects
PDF [150K] of the slides
Audio [.wav 35MB] Audio [.aif 3.8MB] Audio [.mp3 9MB, complete]


Tuesday, Nov 13th
Garrett Lisi, FQXi

Title: A connection with everything.
PDF [2MB] of the slides
alternate PDF [8MB] of the slides
Audio [.wav 30MB] Audio [.aif 3MB] Audio [.mp3 7MB, complete]


Tuesday, Oct 30
Dan Christensen, UWO

Title: Computations involving SN, SF, QG and LGT.
PDF [600KB] of the slides

Audio [.wav 36MB] Audio [.aif 4MB]


Tuesday, Oct 16
David Sloan, PennState

Title: Strong gravity and the BKL conjecture
PDF [260KB] of the slides
Audio [.mp3 8MB] Audio [.aif 4MB] of the slides


Tuesday, Sep 18th (at 9:15 AM US Central time)
Jonathan Engle, Marseille

Title: The loop quantum gravity vertex: a proposal
PDF [260KB] of the slides
Audio [.wav 42MB] Audio [.aif 4MB]


Tuesday, Sep 4th (at 9:15 AM US Central time)
Johannes Tambornino, Aachen

Title: Relational observables and cosmological perturbation theory
PDF [860KB] of the slides
Audio [.wav 38MB] Audio [.aif 4MB]


Tuesday, May 15th
Laurent Freidel, Perimeter Institute

Title: Matter coupling to 3d quantum gravity and effective field theory I
PDF [10MB] of the slides
Audio [.mp3 65MB] Audio [.aif 6MB]


Tuesday, April 24th
Martin Bojowald, PennState

Title: The KITP program on quantum singularities (encore)
PDF [420K] of the slides
Audio [.mp3 12MB] Audio [.aif 6MB]


Tuesday, April 10th
Jose Antonio Zapata, UNAM Morelia

Title: Effective theories, continuum limit and background independence in LQG
PDF [ 370kb] of the slides
Audio [.mp3 53MB] Audio [.aif 4MB]


Tuesday, April 3rd
Lee Smolin, Perimeter Institute

Title: Emergent chiral excitations of quantum geometries: progress report
PDF of the slides [5.5MB]
Audio [.mp3 56MB] Audio [.aif 5MB]


Tuesday, March 27th
Jorge Pullin, Louisiana State

Title: Spherically symmetric loop quantum gravity
PDF of the slides [2MB]
Audio [.wav 26MB] Audio [.aif 5MB]


Tuesday, March 20th
Kirill Krasnov, Perimeter Institute

Title: Non metric gravity
PDF of the slides [128k]
Audio [.aif 6MB] Audio [.wav 4MB]


Tuesday, March 13th
Michele Arzano, Perimeter Institute

Title: Quantum fields and Noether charges for kappa-spacetime symmetries
PDF of the slides [268k]
Audio [.aif, 8MB] Audio [.wav, 4MB]

Abstract: After a brief review of the kappa-Poincare' Hopf algebra I will discuss how it can be used to describe the symmetries of kappa-Minkowski non-commutative spacetime. In particular I will focus on how apparent ambiguities in defining the action of translations can be overcome and how conserved Noether charges can be associated with such symmetries. Moving from the classical to the quantum field framework, I will first recall some older results on perturbative calculations in a path-integral approach for phi^4 scalar field theory. I will then show how recent work on the symplectic structure of classical kappa-fields suggests a new approach to canonical quantization of free fields and I will close with some remarks on the recent efforts and results on such topic.


Tuesday, March 6th
Alejandro Corichi, UNAM Morelia

Title: Relation between Schroedinger and polymer quantum mechanics
PDF of the slides [190k]
Audio [.aif, 8MB]

Abstract:
The relation between the ordinary Schroedinger representation and the so-called polymer representation will be explored. We will show how the polymer representation can be obtained as an appropriate limit of the Schroedinger one, and how we can recover this one by means of a precise renormalization procedure of the polymer quantum mechanics. Some examples will be discussed.


Tuesday February 27th
Abhay Ashtekar, PennState

Title: Diffeomorphism invariance in LQG
PDF [105K] of the slides
Audio [.wav, 39MB] Audio [.aif, 4MB]


Tuesday February 20th
Martin Bojowald, PennState

Title: KITP program on singularities summary
PDF [420K] of the slides
[there were problems with the audio, talk will be repeated 4/21]


Tuesday February 13th
Radu Roiban, PennState

Title: On the UV properties of N=8 supergravity: is it finite?

PDF [190K] of the slides
Audio [.wav, 38MB] Audio [.aif, 4MB]


2006


Tuesday November 28th
Bianca Dittrich, Perimeter Institute

PDF [196K] of the slides
Audio [.wav, 29MB] Audio [.aif, 3MB] Title: Approximate observables


Tuesday November 7th
Alex Corichi, UNAM Morelia
Title: Quantum Isolated Horizons: The Planck regime

PDF [171K] of the slides
Audio [.wav, 33MB] Audio [.aif, 3MB]


Tuesday November 7th
Winston Fairbairn, Ecole Normale Lyon
Title: Matter in quantum BF theory

PDF [171K] of the slides
Audio [.wav, 34MB] Audio [.aif, 3MB]


Tuesday October 31st.
Guillermo Mena Marugan, CSIC, Madrid, Spain
Title: Inhomogeneous quantum cosmology: the Gowdy T3 model

PDF [430K] of the slides
Audio [.wav, 38MB] Audio [.aif, 4MB]


Tuesday October 17th.
Robert Oeckl, UNAM Morelia
Title: Quantum gravity, probabilities and general boundaries

PDF [700K] of the slides
Audio [.wav, 41MB] Audio [.aif, 4MB]

Abstract: In quantum field theory, knowing all transition amplitudes or the S-matrix is usually considered sufficient to specify the physical content of a theory. We are often accustomed to adopt a similar attitude when developing quantum gravity, concentrating on technical advances. I want to start this talk with a reminder that conceptual problems with the physical interpretation of quantities in quantum gravity remain open. In particular, I will review the problem of time and what I shall call the quantum cosmology problem. I will then review the general boundary formulation of quantum theory and explain in which sense it addresses these problems. The key conceptual step in this is a generalization of the probability rule of quantum theory and of the associated notion of probability conservation. Finally, I want to discuss the recent application of the general boundary formulation in the context of graviton amplitudes from a conceptual point of view.


Tuesday October 10th.
Fernando Barbero, CSIC, Madrid
Title: Perturbative treatment of 2+1 gravity with scalars

PDF [180K] of the slides
Audio [.wav, 31MB] Audio [.aif, 3MB]


Tuesday October 3rd.
Simone Speziale, Perimeter Institute
Title: Graviton propagator from loop quantum gravity II

PDF [1MB] of the slides
Audio [.wav, 40MB] Audio [.aif, 4MB]


Tuesday September 26th.
Carlo Rovelli, CPT Marseille
Title: Graviton propagator from loop quantum gravity

PDF [2MB] of the slides
Audio [.wav, 44MB] Audio [.aif, 4.6MB]


Tuesday September 19th.
Abhay Ashtekar, PennState
Title: Loop quantum gravity frequently asked questions

PDF [46kb] of the slides
Audio [.wav, 33MB] Audio [.aif, 3MB]

Abstract:
This is based on the MG11 invited talk


Tuesday June 27th.
Frank Saueressig, Utrecht
Title: Renormalization group improved cosmologies

PDF [223k] of the slides
Audio [.wav, 33MB] Audio [.aif, 3MB]

Abstract:
Title: Renormalization group improved cosmologies Abstract: It is generally believed that in the very early universe, at times smaller than the Planck time, quantum gravity effects play a crucial role. Since the physics in the Planck era prepares the initial conditions for the subsequent classical evolution of the universe it is desirable to gain some understanding of the quantum gravitational processes which took place immediately after the Big Bang. Based on the Einstein-Hilbert approximation of asymptotically safe quantum gravity we discuss a consistent renormalization group based framework which allows for the inclusion of such quantum gravitational effects into the cosmological field equations and applies to all stages of the cosmological evolution. The very early universe is found to contain a period of "oscillatory inflation". Lateron the cosmological evolution is classical and asymtotes to a de Sitter era at cosmologically late times.


Tuesday June 20th.
Andrzej Okolow, Warszaw
Title: Quantization of diffeomorphism invariant theories of connections with a non-compact structure group --- an example

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Audio [.wma, 33MB] Audio [.wav, 48MB] Audio [.aif, 3.5MB]

Abstract:
A simple diffeomorphism invariant theory of connections with the non-compact structure group R of real numbers is quantized. The theory is defined on a four-dimensional 'space-time' by an action resembling closely the self-dual Plebanski action for general relativity. The space of quantum states is constructed by means of projective techniques by Kijowski. Except this point the applied quantization procedure is based on Loop Quantum Gravity methods.


Tuesday June 13th.
No talk.

Tuesday June 6th.
Parampreet Singh (PennState).
Title: The Big Bang and Loop Quantum Cosmology

PDF [1 MB] of the slides
Audio [.wav, 35MB] Audio [.aif, 3.7MB] of the talk of the talk

Abstract:
The talk deals with the recent developments in homogeneous and isotropic loop quantum cosmology on the Planck scale physics near the Big Bang. By constructing the physical Hilbert space, Dirac observables and physical semi-classical states definite and robust predictions about quantum nature of big bang can be made. The analysis leads to a prediction that the current, classical, expanding phase of the Universe is deterministically joined to a contracting phase by a quantum gravitational bridge. Quantum geometric effects at Planck scales make gravity replusive replacing big bang singularity with a big bounce.


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