Matthew Johnson

Research Interests

The goal of my research is to understand the fundamental laws of nature through their impact on cosmology. I am primarily a theorist, dabbling in cosmology, field theory, string theory, and gravitation. I also design data analysis algorithms to confront fundamental theory with observations of the Cosmic Microwave Background (CMB) radiation. Here is a sampling of questions that my research aims to answer: How big is the universe? What might lie beyond our observable universe, and how could we confirm or disprove various proposals? What role do the extra dimensions predicted by string theory play in cosmology? Are there new ways of looking at cosmological datasets that could be useful when confronting theories with data? Can computer simulations of the very early universe shed light on it's possible initial conditions and evolution?

Positions Held

• 2017-present York University and Perimeter Institute, Associate Professor 2012 - 2017 York University and Perimeter Institute, Assistant Professor 2010 - 2012 Perimeter Institute for Theoretical Physics, Postdoctoral Scholar 2007 - 2010 California Institute of Technology, Moore Postdoctoral Scholar

Recent Publications

• S. C. Hotinli, J. Meyers, N. Dalal, A. Jaffe, M. C. Johnson, J. B. Mertens, M. Münchmeyer, K. M. Smith, and A. van Engelen, Transverse velocities with the moving lens effect, Phys. Rev. Lett. 123, 061301 (2019).
• J. Braden, M. C. Johnson, H. V. Peiris, A. Pontzen, and S. Weinfurtner, A new semiclassical picture of vacuum decay, Phys. Rev. Lett. 123, 031601 (2019).
• J. Huang, M. C. Johnson, L. Sagunski, M. Sakellariadou, and J. Zhang, Prospects for axion searches with Advanced LIGO through binary mergers, Phys. Rev. D99, 063013 (2019).
• A. Deutsch, E. Dimastrogiovanni, M. C. Johnson, M. Münchmeyer, and A. Terrana, Reconstruction of the remote dipole and quadrupole fields from the kinetic Sunyaev Zel"dovich and polarized Sunyaev Zel"dovich effects, Phys. Rev. D98, 123501 (2018).
• J. Cayuso, M. C. Johnson, and J. Mertens, Simulated reconstruction of the remote dipole field using the kinetic Sunyaev Zel'dovich effect, Phys. Rev. D 98, 063502 (2018).
• N. Afshordi and M. C. Johnson, Cosmological Zero Modes, Phys. Rev. D 98, 023541 (2018).
• J. Braden, M. C. Johnson, H. V. Peiris, and S. Weinfurtner, Towards the cold atom analog false vacuum, JHEP 07 014 (2018).
• A. Deutsch, M. C. Johnson, M. Munchmeyer, and A. Terrana, Polarized Sunyaev Zel'dovich tomography, JCAP 04 034 (2018).
• L. Sagunski, J. Zhang, M. C. Johnson, L. Lehner, M. Sakellariadou, S. L. Liebling, C. Palenzuela, and D. Neilsen, Neutron star mergers as a probe of modifications of general relativity with finite-range scalar forces, Phys. Rev. D 97, 064016 (2018).
• Jonathan Braden, Matthew C. Johnson, Hiranya V. Peiris, and Anthony Aguirre, Constraining cosmological ultra-large scale structure using numerical relativity, Phys. Rev. D96, 023541 (2017), arXiv: 1604.04001.
• Chad Hanna, Matthew C. Johnson, and Luis Lehner, Estimating gravitational radiation from super-emitting compact binary systems, Phys. Rev. D95, 124042 (2017), arXiv: 1611.03506.
• Alexandra Terrana, Mary-Jean Harris, and Matthew C. Johnson, Analyzing the cosmic variance limit of remote dipole measurements of the cosmic microwave background using the large-scale kinetic Sunyaev Zel"dovich effect, Journal of Cosmology and Astroparticle Physics (JCAP) 02 040 (2017), arXiv: 1610.06919.
• Matthew C. Johnson, Carroll L. Wainwright, Hiranya V. Peiris, and Anthony Aguirre, Simulating the universe(s) III: Observables for the full bubble collision spacetime, Journal of Cosmology and Astroparticle Physics (JCAP) 07 020 (2016), arXiv: 1508.03786.
• Matthew C. Johnson and Wei Lin, Observable signatures of classical transitions, JCAP 03 051 (2016), arXiv: 1508.03786.
• Stephen M. Feeney, Franz Elsner, Matthew C. Johnson, and Hiranya V. Peiris, Forecasting constraints from the cosmic microwave background radiation on eternal inflation, Phys. Rev. D92, 083515 (2015), arXiv: 1506.01716.
• Matthew C. Johnson and Alexandra Terrana, Tensor modes in bigravity: primordial to present, arXiv: 1503.05560 (2015). Phys. Rev. D 92, 044001 (2015), arxiv:1503.05560.
• Pengjie Zhang and Matthew C. Johnson, Testing eternal inflation with the kinetic Sunaev Zel'dovich effect, Journal of Cosmology and Astroparticle Physics (JCAP) 06 046 (2015), arXiv: 1501.00511.
• Richard Brito, Alexandra Terrana, Matthew C. Johnson, and Vitor Cardoso, The nonlinear dynamical stability of infrared modifications of gravity, Phys. Rev. D90, 124035 (2014). arXiv: 1409.0886
• Carroll L. Wainwright, Matthew C. Johnson, Hiranya V. Peiris, and Anthony Aguirre, Simulating the universe(s) II: phenomenology of cosmic bubble collisions in full General Relativity, JCAP 10 024 (2014), arXiv: 1407.2950.
• Carroll L. Wainwright, Matthew C. Johnson, Hiranya V. Peiris, Anthony Aguirre, Luis Lehner, and Steven L. Liebling, Simulating the universe(s): from cosmic bubble collisions to cosmological observables with numerical relativity, JCAP 03 030 (2014). arXiv: 1312.1357
• Stephen M. Feeney, Matthew C. Johnson, Jason D. McEwan, Daniel J. Mortlock, Hiranya V. Peiris, Hierarchical Bayesian Detection Algorithm for Early-Universe Relics in the Cosmic Microwave Background, Phys. Rev. D88, 043012 (2013). arXiv: 1210.2725
• Stephen M. Feeney, Matthew C. Johnson, Daniel J. Mortlock, Hiranya V. Peiris, A robust constraint on cosmic textures from the cosmic microwave background, Phys.Rev.Lett. 108, 241301 (2012), arXiv: 1203.1928.
• Jason D. McEwen, Stephen M. Feeney, Matthew C. Johnson, Hiranya V. Peiris, Optimal filters for detecting cosmic bubble collisions, Phys.Rev. D85, 103502 (2012), 1202.2861
• Matthew C. Johnson and Jean-Luc Lehners, Cycles in the Multiverse, Phys.Rev. D85, 103509 (2012), arXiv: 1112.3360.
• Matthew C. Johnson, Hiranya V. Peiris, Luis Lehner, Determining the outcome of cosmic bubble collisions in full General Relativity, Phys.Rev. D85, 083516 (2012), arXiv: 1112.4487.
• Anthony Aguirre, Sean M. Carroll, Matthew C. Johnson, Out of equilibrium: understanding cosmological evolution to lower-entropy states, JCAP 1202, 024 (2012), arXiv: 1108.0417.
• Stephen M. Feeney, Matthew C. Johnson, Daniel J. Mortlock, Hiranya V. Peiris, First Observational Tests of Eternal Inflation: Analysis Methods and WMAP 7-Year Results, Phys. Rev. D 84, 043507 (2011), arXiv: 1012.3667.
• Stephen M. Feeney, Matthew C. Johnson, Daniel J. Mortlock, Hiranya V. Peiris, First Observational Tests of Eternal Inflation, Phys. Rev. Lett. 107, 071301 (2011), arXiv: 1012.1995.
• F. McCarthy and M. C. Johnson, Remote dipole field reconstruction with dusty galaxies, arXiv: 1907.06678 (2019).
• Z. Pan and M. C. Johnson, Forecasted constraints on modified gravity from Sunyaev Zel"dovich tomography, arXiv: 1906.04208 (2019).
• J. Braden, M. C. Johnson, H. V. Peiris, A. Pontzen, and S. Weinfurtner, Nonlinear dynamics of the cold atom analogue false vacuum, arXiv: 1904.07873 (2019).
• D. Contreras, M. C. Johnson, and J. M. Mertens, Towards detection of relativistic effects in galaxy number counts using kSZ tomography, arXiv: 1904.10033 (2019).
• J. I. Cayuso and M. C. Johnson, Towards testing CMB anomalies using the kinetic and polarized Sunyaev Zel"dovich effects, arXiv: 1904.10981 (2019).
• M. Münchmeyer, M. S. Madhavacheril, S. Ferraro, M. C. Johnson, and K. M. Smith, Constraining local non-Gaussianities with kSZ tomography, 1810.13424 (2018).
• A. Deutsch, E. Dimastrogiovanni, M. Fasiello, M. C. Johnson, and M. Münchmeyer, Primordial gravitational wave phenomenology with polarized Sunyaev Zel"dovich tomography, arXiv: 1810.09463 (2018).
• K. M. Smith, M. S. Madhavacheril, M. Münchmeyer, S. Ferraro, U. Giri, and M. C. Johnson, KSZ tomography and the bispectrum, arXiv: 1810.13423 (2018).
• A. Sloszar, et. al Packed Ultra-wideband Mapping Array (PUMA): A radio telescope for cosmology and transients, arXiv: 1907.12559 (2019).
• N. Sehgal, et. al CMB-HD: An ultra-deep, high-resolution millimeter-wave survey over half the sky, arXiv: 1906.10134 (2019).
• M. Alvarez, et. al Testing inflation with large scale structure: connecting hopes with reality, arXiv: 1412.4671 (2014).

Seminars

• A new semiclassical picture of vacuum decay, Caltech
• A new semiclassical picture of vacuum decay, Tufts University
• Fundamental physics with the Sunayaev Zel"dovich effect, The CMB in HD: the low-noise high-resolution frontier, Centre for Computational Astrophysics
• Early Universe cosmology with the Sunyaev Zel'dovich effect, PASCOS
• Understanding the Ultra Large Scale Structure of the Universe through observation and theory, Centre de Physique Theorique Marseille
• Understanding the Ultra Large Scale Structure of the Universe through observation and theory, University of Texas Austin
• Mapping the Universe on the largest scales with the Sunyaev Zel'dovich effect, Rice University
• Understanding the Ultra Large Scale Structure of the Universe through observation and theory, University of Minnesota
• Exploring the ultra-large scale structure of the Universe, Advances in Theoretical Cosmology in Light of Data conference at NORDITA
• Mapping ultra large scale structure, Case Western Reserve University
• General relativistic non-linearities in cosmology, 2016 Midwest Relativity Meeting
• General relativistic non-linearities in cosmology, GR21 Conference
• Observable non-linearities in cosmology, Canadian Conference on General Relativity and Relativistic Astrophysics
• Constraining cosmological ultra large scale structure using numerical relativity, Theory Canada 11
• Constraining cosmological ultra large scale structure using numerical relativity, Great Lakes Cosmology and Galaxies 2016
• Constraining inflationary initial conditions, University of Amsterdam
• Searching for other Universes, University of Toronto, Physics Colloquium
• Inverse problems in early Universe cosmology, Fields Institute, Inverse Problems and Image Analysis Seminar
• Testing eternal inflation, Case Western Reserve University
• Searching for other Universes, Carleton University, Physics Colloquium
• Quantum in Cosmology, NASA Blue Sky Meeting on Quantum Technologies
• Searching for other Universes, McMaster University, Physics Colloquium
• Acts of Faith: what we assume, and then forget, about our research, Scifoo conference
• Latest constraints and forecasts for testing eternal inflation, Caltech
• Inferring the Universe, York University Math and Statistics
• Simulating the Universe(s), CITA
• Early Universe Cosmology, CAP Congress
• Simulating the Universe(s), Canadian Conference on General Relativity and Relativistic Astrophysics
• Simulating the Universe(s), Imperial College London
• Eternal Inflation, University of Waterloo
• Eternal Inflation, Quantum Gravity and Fundamental Cosmology Workshop, Albert Einstein Institute, Potsdam Germany
• Searching for early-universe relics in the CMB, McGill University
• PIRSA:19020072, Reconstructing the Universe with secondary CMB anisotropies, 2019-02-20, Colloquium
• PIRSA:16070064, Matthew Johnson ISSYP 2016 Keynote - Searching for Other Universes, 2016-07-22,
• PIRSA:15080112, Introduction to Cosmology - Matt Johnson, 2015-08-28, PSI 2015/2016 Introduction to Cosmology - Matt Johnson
• PIRSA:15080111, Introduction to Cosmology - Matt Johnson, 2015-08-27, PSI 2015/2016 Introduction to Cosmology - Matt Johnson
• PIRSA:15080110, Introduction to Cosmology - Matt Johnson, 2015-08-25, PSI 2015/2016 Introduction to Cosmology - Matt Johnson
• PIRSA:14080035, 14/15 PSI - Differential Geormetry, 2014-08-28,
• PIRSA:14080034, 14/15 PSI - Differential Geormetry, 2014-08-27,
• PIRSA:14080033, 14/15 PSI - Differential Geormetry, 2014-08-26,
• PIRSA:14080032, 14/15 PSI - Differential Geormetry, 2014-08-25,
• PIRSA:14070025, Searching for Other Universes, 2014-07-14, ISSYP 2014
• PIRSA:14070020, EinsteinPlus 2014 - Cosmology Keynote, 2014-07-08, EinsteinPlus 2014
• PIRSA:14040059, 13/14 PSI - Explorations in Cosmology - Lecture 14, 2014-04-25, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040058, 13/14 PSI - Explorations in Cosmology - Lecture 13, 2014-04-24, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040057, 13/14 PSI - Explorations in Cosmology - Lecture 12, 2014-04-23, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040056, 13/14 PSI - Explorations in Cosmology - Lecture 11, 2014-04-22, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040055, 13/14 PSI - Explorations in Cosmology - Lecture 10, 2014-04-21, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040051, 13/14 PSI - Explorations in Cosmology - Lecture 9, 2014-04-17, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040050, 13/14 PSI - Explorations in Cosmology - Lecture 8, 2014-04-16, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040049, 13/14 PSI - Explorations in Cosmology - Lecture 7, 2014-04-15, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040048, 13/14 PSI - Explorations in Cosmology - Lecture 6, 2014-04-14, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040045, 13/14 PSI - Explorations in Cosmology - Lecture 5, 2014-04-11, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040044, 13/14 PSI - Explorations in Cosmology - Lecture 4, 2014-04-10, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040043, 13/14 PSI - Explorations in Cosmology - Lecture 3, 2014-04-09, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040042, 13/14 PSI - Explorations in Cosmology - Lecture 2, 2014-04-08, 13/14 PSI - Explorations in Cosmology
• PIRSA:14040041, 13/14 PSI - Explorations in Cosmology - Lecture 1, 2014-04-07, 13/14 PSI - Explorations in Cosmology
• PIRSA:14010101, Simulating the Universe(s), 2014-01-14, Cosmology & Gravitation
• PIRSA:13070058, Quantum Cosmology - 3, 2013-07-23, Loops 13
• PIRSA:13070029, Searching for Other Universes, 2013-07-08, ISSYP 2013
• PIRSA:13040080, 12/13 PSI - Explorations in Cosmology Lecture 15, 2013-04-26, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040079, 12/13 PSI - Explorations in Cosmology Lecture 14, 2013-04-25, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040078, 12/13 PSI - Explorations in Cosmology Lecture 13, 2013-04-24, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040077, 12/13 PSI - Explorations in Cosmology Lecture 12, 2013-04-23, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040076, 12/13 PSI - Explorations in Cosmology Lecture 11, 2013-04-22, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040073, 12/13 PSI - Explorations in Cosmology Lecture 10, 2013-04-19, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040072, 12/13 PSI - Explorations in Cosmology Lecture 9, 2013-04-18, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040071, 12/13 PSI - Explorations in Cosmology Lecture 8, 2013-04-17, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040070, 12/13 PSI - Explorations in Cosmology Lecture 7, 2013-04-16, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040069, 12/13 PSI - Explorations in Cosmology Lecture 6, 2013-04-15, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040066, 12/13 PSI - Explorations in Cosmology Lecture 5, 2013-04-12, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040065, 12/13 PSI - Explorations in Cosmology Lecture 4, 2013-04-11, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040064, 12/13 PSI - Explorations in Cosmology Lecture 3, 2013-04-10, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040063, 12/13 PSI - Explorations in Cosmology Lecture 2, 2013-04-09, 12/13 PSI - Explorations in Cosmology
• PIRSA:13040062, 12/13 PSI - Explorations in Cosmology Lecture 1, 2013-04-08, 12/13 PSI - Explorations in Cosmology
• PIRSA:12100050, 12/13 PSI Researcher Presentation, 2012-10-24, 12/13 PSI Researcher Presentations
• PIRSA:12020144, Feature-finding in the cosmic microwave background, 2012-02-09, Workshop: Computational Methods at Perimeter
• PIRSA:11010114, Observational tests of eternal inflation, 2011-01-25, Cosmology & Gravitation
• PIRSA:09070023, Dynamical compactification from higher dimensional de Sitter space, 2009-07-16, Holographic Cosmology Conference
• PIRSA:06120021, Bubble Nucleation and Eternal Inflation, 2006-12-05, Young Researchers Conference - 2006