Cosmologists at Perimeter Institute seek to help pin down the constituents and history of our universe, and the rules governing its origin and evolution. Many of the most interesting clues about physics beyond the standard model (e.g., dark matter, dark energy, the matter/antimatter asymmetry, and the spectrum of primordial density perturbations], come from cosmological observations, and cosmological observations are often the best way to test or constrain a proposed modification of the laws of nature, since such observations can probe length scales, time scales, and energy scales that are beyond the reach of terrestrial laboratories.
Format results

24 talksCollection NumberC17021
Talk

General Relativity for Cosmology  Lecture 1
University of Waterloo 
General Relativity for Cosmology  Lecture 2
University of Waterloo 
General Relativity for Cosmology  Lecture 3
University of Waterloo 
General Relativity for Cosmology  Lecture 4
University of Waterloo 
General Relativity for Cosmology  Lecture 5
University of Waterloo 
General Relativity for Cosmology  Lecture 6
University of Waterloo 

General Relativity for Cosmology  Lecture 8
University of Waterloo


Bounce Scenarios in Cosmology
16 talksCollection NumberC17024Talk

Welcome and Opening Remarks

University of Sheffield

University of Edinburgh


Bounce in Loop Quantum Cosmology and its Implications
Pennsylvania State University 
Observable Consequences of a Bounce
Canadian Institute for Theoretical Astrophysics (CITA) 
Challenges for Bouncing Cosmologies
McGill University  Department of Physics 
Emergent bouncing cosmology from quantum gravity condensates
University of New Brunswick 
Discussion Session 2

TotalEnergies (France)

University of Sheffield

Arthur B. McDonald Canadian Astroparticle Physics Research Institute





PSI 2016/2017  Explorations in Cosmology (Smith)
14 talksCollection NumberC17012Talk

PSI 2016/2017  Explorations in Cosmology  Lecture 1
Perimeter Institute for Theoretical Physics 
PSI 2016/2017  Explorations in Cosmology  Lecture 2
Perimeter Institute for Theoretical Physics 
PSI 2016/2017  Explorations in Cosmology  Lecture 3
Perimeter Institute for Theoretical Physics 
PSI 2016/2017  Explorations in Cosmology  Lecture 4
Perimeter Institute for Theoretical Physics 
PSI 2016/2017  Explorations in Cosmology  Lecture 5
Perimeter Institute for Theoretical Physics 
PSI 2016/2017  Explorations in Cosmology  Lecture 6
Perimeter Institute for Theoretical Physics 
PSI 2016/2017  Explorations in Cosmology  Lecture 7
Perimeter Institute for Theoretical Physics 
PSI 2016/2017  Explorations in Cosmology  Lecture 8
Perimeter Institute for Theoretical Physics


PSI 2016/2017  Cosmology (Kubiznak)
15 talksCollection NumberC17003Talk

PSI 2016/2017  Cosmology (Review)  Lecture 1
Charles University 
PSI 2016/2017  Cosmology (Review)  Lecture 2
Charles University 
PSI 2016/2017  Cosmology (Review)  Lecture 3
Charles University 
PSI 2016/2017  Cosmology (Review)  Lecture 4
Charles University 
PSI 2016/2017  Cosmology (Review)  Lecture 5
Charles University 
PSI 2016/2017  Cosmology (Review)  Lecture 6
Charles University 
PSI 2016/2017  Cosmology (Review)  Lecture 7
Charles University 
PSI 2016/2017  Cosmology (Review)  Lecture 8
Charles University


Time in Cosmology
14 talksCollection NumberC16016Talk

Welcome and Opening Remarks

Institute for Astrophysics and Space Sciences

Perimeter Institute for Theoretical Physics

University of Edinburgh



The origin of arrows of time II

California Institute of Technology (Caltech)  Division of Physics Mathematics & Astronomy

Institute for Astrophysics and Space Sciences

Technical University of Applied Sciences WürzburgSchweinfurt


The origin of arrows of time II cont.

California Institute of Technology (Caltech)  Division of Physics Mathematics & Astronomy

Institute for Astrophysics and Space Sciences

Technical University of Applied Sciences WürzburgSchweinfurt


Testing time asymmetry in the early universe

University of California, San Diego

University of Lisbon

University of California, Berkeley


The fate of the big bang

Pennsylvania State University

University of Edinburgh


Time as Organization – Downward Caustation, Structure and Complexity I
Technische Universität Darmstadt 
Time as Organization – Downward Caustation, Structure and Complexity II

Santa Fe Institute

University of Cape Town



Cosmological Frontiers in Fundamental Physics 2016
21 talksCollection NumberC16009Talk

Welcome and Opening Remarks
PIRSA:16060006 
Dark matter phenomenology across cosmic times
Johns Hopkins University 



A new probe of primordial magnetic fields at high redshift
University of Southern California 
Turbulent gravity in asymptotically AdS spacetimes
University of Nottingham 
Black hole ringdown and quasinormal modes
The University of Texas at Austin


Feedback over 44 Orders of Magnitude: From Gammarays to the Universe
22 talksCollection NumberC16004Talk

30000 foot view of blazar heating
Universität Heidelberg  Institut für Theoretische Physik 
The basics and notsobasic physics of beam plasmas
University of CastillaLa Mancha 
The Basics of the Gammaray Sky: current observational status and future perspectives
Max Planck Institute for Gravitational Physics  Albert Einstein Institute (AEI) 
The thermal state of the intergalactic medium and its effect on galaxy formation
University of Washington 
Models of Galaxy formation: Current constraints on the star formation history and feedback
University of Massachusetts Amherst 
Nonlinear Plasma Instabilities
University of WisconsinMilwaukee 



Superluminality in Effective Field Theories for Cosmology
17 talksCollection NumberC15019Talk


Causal structures in Massive gravity and GaussBonnet gravity
National Taiwan University 




Causality constraints and the lightcone
Swansea University 


Lecture  Relativity, PHYS 604
Perimeter Institute for Theoretical Physics 
Lecture  Relativity, PHYS 604
Perimeter Institute for Theoretical Physics 
Cosmology in the Era of MultiWavelength Surveys
Yale University 
Geometric Machine Learning for cosmological galaxy models
Princeton University

General Relativity for Cosmology (PHYS786/AMATH875)  Achim Kempf
24 talksCollection NumberC17021General Relativity for Cosmology (PHYS786/AMATH875)  Achim Kempf 

PSI 2016/2017  Explorations in Cosmology (Smith)
14 talksCollection NumberC17012PSI 2016/2017  Explorations in Cosmology (Smith) 
PSI 2016/2017  Cosmology (Kubiznak)
15 talksCollection NumberC17003PSI 2016/2017  Cosmology (Kubiznak) 

Cosmological Frontiers in Fundamental Physics 2016
21 talksCollection NumberC16009Cosmological Frontiers in Fundamental Physics 2016 
Feedback over 44 Orders of Magnitude: From Gammarays to the Universe
22 talksCollection NumberC16004Feedback over 44 Orders of Magnitude: From Gammarays to the Universe

Superluminality in Effective Field Theories for Cosmology
17 talksCollection NumberC15019Superluminality in Effective Field Theories for Cosmology 


Cosmology in the Era of MultiWavelength Surveys
Yale UniversityWe are entering the golden age of multiwavelength astronomical surveys. In the 2020s, a plethora of surveys (such as Euclid, eROSITA, RubinLSST, Simons Observatory, and CMBS4) are underway or planned to provide unprecedented insights into cosmology and astrophysics. In this talk, I will discuss the significant scientific opportunities and challenges that arise in the era of big data, highlighting recent advances in computational modeling and the roles of artificial intelligence and machine learning.

Geometric Machine Learning for cosmological galaxy models
Princeton UniversityGalaxies are the medium through which we study the structure of the universe. However, widely applied statistical models of galaxies are generally oversimplified: even recently proposed models cannot capture the dependencies on environment or formation history. To solve this problem, I will introduce Graph Neural Networks (GNNs), a general and ideal tool for physical modelling. Geometrically constrained GNNs vastly improve our models, and allow us to ask detailed questions about the importance of formation history and environment for cosmological galaxy modeling. I will also prove a surprising equivalence between these two aspects of galaxy formation.