Matthew C. Johnson

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Moore Postdoctoral Scholar in Theoretical Physics, Caltech, Pasadena, CA USA

Office: 465 Lauritsen
email: mjohnson@theory.caltech.edu
phone: 626-395-6603
CV





Index

  1. Research
  2. Teaching
  3. Publications
  4. Talks



Research


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I am a theoretical cosmologist. My research focuses on connections between high energy physics and the cosmology of the very early universe. Some of the research questions I am currently exploring include: What are the dynamical processes by which different vacua of a theory can be accessed? Could there be directly observable effects of eternal inflation? What types of cosmologies are consistent with the existence of extra dimensions? What might it mean to make predictions in an eternally inflating universe?

Read some popular accounts of my research here:

S. Carroll, Making extra dimensions disappear. Weblog, Cosmic Variance, 22 April 2009.
D. Steele, Cosmic Collisions. Cosmos, February 2009.
S. Carroll, Where does the entropy go? Weblog, Cosmic Variance, 12 January 2009.
Z. Merali, Is the evidence for 'alien' universes all around us? New Scientist, 9 May 2007.



Teaching



Some of the materials I developed for TA training during my tenure as the Head TA at UC Santa Cruz:
TA training handout.
Guidelines for writing narrative evaluations.



Publications



A. Aguirre, M. C. Johnson, and M. Larfors, Runaway dilatonic domain walls, arXiv:0911.4342 [hep-th] (2009).

A. Aguirre and M. C. Johnson, A status report on the observability of cosmic bubble collisions, arXiv:0908.4105 [hep-th] (2009).

S. M. Carroll, M. C. Johnson, and L. Randall, Dynamical compactification from de Sitter space, JHEP 11, 094 (2009), arXiv:0904.3115 [hep-th].

S. M. Carroll, M. C. Johnson, and L. Randall, Extremal limits and black hole entropy, JHEP 11, 109 (2009), arXiv:0901.0931 [hep-th].

A. Aguirre, M. C. Johnson, and M. Tysanner, Surviving the crash: assessing the aftermath of cosmic bubble collisions, Phys. Rev. D79, 123514 (2009), arXiv:0811.0866 [hep-th].

M. C. Johnson and M. Larfors, An obstacle to populating the string theory landscape, Phys. Rev. D78, 123513 (2008), arXiv:0809.2604 [hep-th].

M. C. Johnson and M. Larfors, Field Dynamics and tunneling in a flux landscape, Phys. Rev. D78, 083534 (2008), arXiv:0805.3705 [hep-th].

M. C. Johnson and M. Kamionkowski, Dynamical and Gravitational Instability of Oscillating-Field Dark Energy and Dark Matter, Phys. Rev. D78, 063010 (2008), arXiv:0805.1748 [hep-th].

A. Aguirre and M. C. Johnson, Towards observable signatures of other bubble universes II: Exact solutions for thin-wall bubble collisions, Phys. Rev. D77, 123536 (2007), arXiv:0712.3038 [hep-th].

A. Aguirre, M. C. Johnson, and A. Shomer, Towards observable signatures of other bubble universes, Phys. Rev. D76, 063509 (2007), arXiv:0704.3473 [hep-th].

A. Aguirre, S. Gratton, and M. C. Johnson, Measures on Transitions for Cosmology in the Landscape, Phys. Rev. Lett. 98, 131301 (2007), hep-th/0612195.

A. Aguirre, S. Gratton, and M. C. Johnson, Hurdles for Recent Measures in Eternal Inflation, Phys. Rev. D75, 123501 (2007), hep-th/0611221.

T. Banks, M. C. Johnson, and A. Shomer A Note on Gauge Theories Coupled to Gravity, JHEP 09, 049 (2006), hep-th/0606277.

T. Banks, A. Aguirre, and M. C. Johnson, Regulating Eternal Inflation II: The Great Divide, JHEP 08, 065 (2006), hep-th/0603107.

A. Aguirre and M. C. Johnson, Two Tunnels to Inflation, Phys. Rev. D73, 123529 (2006), gr-qc/0512034.

T. Banks and M. C. Johnson, Regulating Eternal Inflation, hep-th/0512141 (2005).

A. Aguirre and M. C. Johnson, Dynamics and instability of false vacuum bubbles, Phys. Rev. D72, 103525 (2005), gr-qc/0508093.

T. Bogdan et al., Waves in the magnetized solar atmosphere II: Waves from localized sources in magnetic flux concentrations, ApJ, 599, 626 (2003).

T. Bogdan et al., Waves in magnetic flux concentrations, Astronomische Nachrichten, 323, 196 (2002).




Talks



LANL and Caltech (bubble collisions), October 2009.
Challenges in Theoretical Cosmology (unstable domain walls), September 2009.
Perimeter Institute (dimension-changing cosmologies), July 2009. ( link to a movie of the talk.)
MCTP (bubble collisions), December 2007.
PhD defense, June 2007.
Santa Barbara Gravity Workshop (instantons), May 2007.
Public talk at PCS High School, April/May 2007.
Stanford (measures and instantons), January 2007.
UC Berkeley (gravity and gauge theories), September 2006.
Inflation+25, June 2006 . ( link to a movie of the talk.)
Orals (stability of false vacuum bubbles), June 2005.