Conference

Displaying 301 - 312 of 4904

Closing Remarks
October 27, 2023

PIRSA:23100088
Quantum Gravity
Branes & Strings, Freedom & Safety and a bit of Cosmology -- Some current problems in Quantum Gravity

Kellogg Stelle
Imperial College London
October 27, 2023

PIRSA:23100021
Quantum Gravity
Panel Discussion - Future Directions in QG (Dittrich, Gregory, Loll, Sakellariadou, Surya)
- Sumati Surya
  Raman Research Institute
- Ruth Gregory
  King's College London
- Renate Loll
  Radboud Universiteit Nijmegen
- Mairi Sakellariadou
  King's College London
- Bianca Dittrich
  Perimeter Institute for Theoretical Physics
October 27, 2023

PIRSA:23100020
Quantum Gravity
Open discussion with today's speakers (Dittrich, Heisenberg, Quevedo, Turok)
- Bianca Dittrich
  Perimeter Institute for Theoretical Physics
- Lavinia Heisenberg
  ETH Zurich
- Fernando Quevedo
  University of Cambridge
- Neil Turok
  University of Edinburgh
October 27, 2023

PIRSA:23100018
Quantum Gravity
A minimal SM/LCDM cosmology

Neil Turok
University of Edinburgh
October 27, 2023

PIRSA:23100063
Quantum Gravity
String Theory and the Cosmological Constant

Fernando Quevedo
University of Cambridge
October 27, 2023

PIRSA:23100069
Quantum Gravity
The simplicial Lorentzian path integral and spin foams

Bianca Dittrich
Perimeter Institute for Theoretical Physics
October 27, 2023

PIRSA:23100068
Quantum Gravity
Balance Laws as Test of Gravity - VIRTUAL

Lavinia Heisenberg
ETH Zurich
October 27, 2023

PIRSA:23100017
Quantum Gravity
Colloquium - Insights from Warped Extra Dimensions - VIRTUAL

Lisa Randall
Harvard University
October 26, 2023

PIRSA:23100016
Quantum Gravity
Panel Discussion - Black hole puzzles (Di Filippo, Gregory, Holdom, Myers, Stelle)
- Francesco Di Filippo
  Kyoto University
- Ruth Gregory
  King's College London
- Bob Holdom
  University of Toronto
- Robert Myers
  Perimeter Institute for Theoretical Physics
- Kellogg Stelle
  Imperial College London
October 26, 2023

PIRSA:23100015
Quantum Gravity
Poster Prize Talk

October 26, 2023

PIRSA:23100019
Open Discussion with today's speakers (Calmet, di Filippo, Gregory)
- Xavier Calmet
  University of Sussex
- Francesco Di Filippo
  Kyoto University
- Ruth Gregory
  King's College London
October 26, 2023

PIRSA:23100014
Quantum Gravity

Closing Remarks
October 27, 2023

PIRSA:23100088
Quantum Gravity
Branes & Strings, Freedom & Safety and a bit of Cosmology -- Some current problems in Quantum Gravity

Kellogg Stelle
Imperial College London
October 27, 2023

PIRSA:23100021
Quantum Gravity
What relations are there between the various ways of wrangling with quantum gravity? String theory is now much more than just a theory of strings -- branes and braneworlds abound. Some kind of effective theory for the familiar world needs to emerge. Are there ways that one could glimpse underlying structure from aspects of an effective theory? That happens for pions -- is there anything like that for gravity? Effective theories also involve higher derivatives, and those can summon up spirits (i.e. ghosts) from the vasty deep. Do asymptotic freedom or asymptotic safety give ways to exorcise them? And what might the effective theory tell us about the earliest times?
Panel Discussion - Future Directions in QG (Dittrich, Gregory, Loll, Sakellariadou, Surya)
- Sumati Surya
  Raman Research Institute
- Ruth Gregory
  King's College London
- Renate Loll
  Radboud Universiteit Nijmegen
- Mairi Sakellariadou
  King's College London
- Bianca Dittrich
  Perimeter Institute for Theoretical Physics
October 27, 2023

PIRSA:23100020
Quantum Gravity
Open discussion with today's speakers (Dittrich, Heisenberg, Quevedo, Turok)
- Bianca Dittrich
  Perimeter Institute for Theoretical Physics
- Lavinia Heisenberg
  ETH Zurich
- Fernando Quevedo
  University of Cambridge
- Neil Turok
  University of Edinburgh
October 27, 2023

PIRSA:23100018
Quantum Gravity
A minimal SM/LCDM cosmology

Neil Turok
University of Edinburgh
October 27, 2023

PIRSA:23100063
Quantum Gravity
Recent observations point to a surprisingly economical description of the universe on both very small and very large scales. Stimulated by these findings, Boyle and I have proposed a new, potentially more complete theoretical framework than currently popular paradigms. Our search has so far led to 1) the simplest-yet explanation for the cosmic dark matter, soon to be tested by galaxy surveys, 2) a thermodynamic explanation for the large scale geometry of the cosmos, based on the concept of gravitational entropy à la Hawking, 3) a new account of the big bang singularity as a “mirror” enforcing CPT-symmetric boundary conditions, realising Penrose's "Weyl curvature hypothesis" and 4) a new mechanism for cancelling the divergent vacuum energy and the trace anomalies in the Standard Model (SM). The new mechanism successfully predicts the primordial density perturbations in terms of the SM’s gauge couplings. It also explains why there are 3 generations of elementary particles, each including a RH neutrino, one of which is stable and comprises the dark matter. I’ll outline the challenges the new picture faces and the opportunities it presents, ranging from solving the gauge hierarchy problem to an improved description of quantum gravity along with prospective observational tests.
String Theory and the Cosmological Constant

Fernando Quevedo
University of Cambridge
October 27, 2023

PIRSA:23100069
Quantum Gravity
An overview is given on moduli stabilization in string theory with emphasis in obtaining de Sitter space solutions. Recent work on vacuum transitions will be emphasised.
The simplicial Lorentzian path integral and spin foams

Bianca Dittrich
Perimeter Institute for Theoretical Physics
October 27, 2023

PIRSA:23100068
Quantum Gravity
I will discuss two versions of the simplicial Lorentizian path integral, namely the (Lorentzian) quantum Regge and the spin foam version. I will do so in the simple context of de Sitter cosmology. This simple example will reveal the important role of light cone irregular configurations in the simplicial path integral — I will show that these can either lead to an exponentially enhanced or an exponentially suppressed amplitude. I will then highlight an important difference between the spin foams and quantum Regge path integral, which affects the probability for the creation of the (de Sitter) universe.
Balance Laws as Test of Gravity - VIRTUAL

Lavinia Heisenberg
ETH Zurich
October 27, 2023

PIRSA:23100017
Quantum Gravity
I will discuss how one can use balance laws in full non-linear general relativity in order to test waveform models (arXiv:2309.12505) --- The presenter will be joining via Zoom for this talk.
Colloquium - Insights from Warped Extra Dimensions - VIRTUAL

Lisa Randall
Harvard University
October 26, 2023

PIRSA:23100016
Quantum Gravity
Warped extra dimensions were originally introduced as a way of addressing the hierarchy problem. But insights from these scenarios have extended to black hole physics, cosmology, and even mechanisms for addressing issues in purely four dimensions. We investigate this scenario and some compelling lessons. The presenter will be joining via Zoom for this talk.
Panel Discussion - Black hole puzzles (Di Filippo, Gregory, Holdom, Myers, Stelle)
- Francesco Di Filippo
  Kyoto University
- Ruth Gregory
  King's College London
- Bob Holdom
  University of Toronto
- Robert Myers
  Perimeter Institute for Theoretical Physics
- Kellogg Stelle
  Imperial College London
October 26, 2023

PIRSA:23100015
Quantum Gravity
Poster Prize Talk

October 26, 2023

PIRSA:23100019
Open Discussion with today's speakers (Calmet, di Filippo, Gregory)
- Xavier Calmet
  University of Sussex
- Francesco Di Filippo
  Kyoto University
- Ruth Gregory
  King's College London
October 26, 2023

PIRSA:23100014
Quantum Gravity

Title	Speaker(s)	Date	Talk Type	Info link
Closing Remarks		2023-10-27	Conference	View details
Branes & Strings, Freedom & Safety and a bit of Cosmology -- Some current problems in Quantum Gravity	Kellogg Stelle	2023-10-27	Conference	View details
Panel Discussion - Future Directions in QG (Dittrich, Gregory, Loll, Sakellariadou, Surya)	Sumati Surya, Ruth Gregory, Renate Loll, Mairi Sakellariadou, Bianca Dittrich	2023-10-27	Conference	View details
Open discussion with today's speakers (Dittrich, Heisenberg, Quevedo, Turok)	Bianca Dittrich, Lavinia Heisenberg, Fernando Quevedo, Neil Turok	2023-10-27	Conference	View details
A minimal SM/LCDM cosmology	Neil Turok	2023-10-27	Conference	View details
String Theory and the Cosmological Constant	Fernando Quevedo	2023-10-27	Conference	View details
The simplicial Lorentzian path integral and spin foams	Bianca Dittrich	2023-10-27	Conference	View details
Balance Laws as Test of Gravity - VIRTUAL	Lavinia Heisenberg	2023-10-27	Conference	View details
Colloquium - Insights from Warped Extra Dimensions - VIRTUAL	Lisa Randall	2023-10-26	Conference	View details
Panel Discussion - Black hole puzzles (Di Filippo, Gregory, Holdom, Myers, Stelle)	Francesco Di Filippo, Ruth Gregory, Bob Holdom, Robert Myers, Kellogg Stelle	2023-10-26	Conference	View details
Poster Prize Talk		2023-10-26	Conference	View details
Open Discussion with today's speakers (Calmet, di Filippo, Gregory)	Xavier Calmet, Francesco Di Filippo, Ruth Gregory	2023-10-26	Conference	View details

Format results