Wolfgang Wieland

Research Interests

Space, time and causality are like a vast ordering structure for our observations. In Newtonian gravity, matter fills this structure according to the dynamical laws, but the structure itself stays rigid. General relativity unfreezed this rigidity: gravity bends spacetime, and the causal structure is itself dynamical. Quantum theory, on the other hand, has taught us that nature is intrinsically probabilistic --” the Heisenberg uncertainty principle sets a fundamental limit to how much we can now about a quantum system. The main theme of my research program is to bring these lessons together to understand the causal structure of spacetime once both quantum theory and general relativity become equally important. On a more technical level, the goal is to quantise the light cone structure of spacetime and treat the causal structure of spacetime as a quantum system itself.

My main research interests are:
- Quantum gravity
- Loop quantum gravity and spinfoam models
- Spin structure of spacetime
- Quasi-local observables/quasi-local realisations of the holographic principle

Positions Held

• 2013--2015, Postdoctoral scholar at the Institute for Gravitation and the Cosmos (Pennsylvania State University, United States)

Awards

• Bronstein Prize in Loop Quantum Gravity (2019)
• Prix de thèse, Aix-Marseille Université (2014)

Recent Publications

• Jeevan Chandra Namburi, W. Wieland, Deformed Heisenberg charges in three-dimensional gravity,
  JHEP 2003 (2020) 175, arXiv: 1912.09514.
• M. Dupuis, F. Girelli, A. Osumanu and W. Wieland, First-order formulation of teleparallel gravity and dual loop gravity,
  Class. Quantum Grav. 37 (2020) 085023, arXiv: 1906.02801.
• W. Wieland, Generating functional for gravitational null initial data,
  Class. Quant. Grav. 36 (2019), 235007, arXiv: 1905.06357.
• W. Wieland, Conformal boundary conditions, loop gravity and the continuum,
  JHEP (2018) 2018: 89, arXiv: 1804.08643.
• E. Adjei, S. Gielen, W. Wieland, Cosmological evolution as squeezing: a toy model for group field cosmology,
  Class. Quantum Grav. 35 (2018), 105016, arXiv: 1712.07266.
• W. Wieland, Quantum gravity in three dimensions, Witten spinors and the quantisation of length,
  Nuclear Physics B 930 (2018), 219-234, arXiv: 1711.01276.
• W. Wieland, New boundary variables for classical and quantum gravity on a null surface,
  Class. Quantum Grav. 34 (2017), 215008 (30pp), arXiv: 1704.07391.
• W. Wieland, Fock Representation of Gravitational Boundary Modes and the Discreteness of the Area Spectrum,
  Ann. Henri Poincaré 18 (2017), 3695, arXiv: 1706.00479.
• W. Wieland, Discrete gravity as a topological field theory with light-like curvature defects,
  JHEP 5 (2017), 142, arXiv: 1611.02784.
• W. Wieland, Quasi-local gravitational angular momentum and centre of mass from generalised Witten equations,
  Gen. Rel. Grav. 49 (2017), 38, arXiv: 1604.07428.
• W. Wieland, New action for simplicial gravity in four dimensions,
  Class. Quant. Grav. 32 (2015), 015016, arXiv: 1407.0025.
• W. Wieland, A one-dimensional action for simplicial gravity in three dimensions,
  Phys. Rev. D 90 (2014), 044008, arXiv: 1402.6708.
• W. Wieland, Hamiltonian spinfoam gravity,
  Class. Quant. Grav. 31 (2014), 025002, arXiv: 1301.5859.
• E. Bianchi, M. Han, E. Magliaro, C. Perini, C. Rovelli, W. Wieland, Spinfoam fermions,
  Class. Quant. Grav. 30 (2013), 235023, arXiv: 1012.4719.
• H. M. Haggard, C. Rovelli, F. Vidotto, W. Wieland, The spin connection of twisted geometry,
  Phys. Rev. D 87 (2013), 024038, arXiv: 1211.2166.
• S. Speziale, W. Wieland, The twistorial structure of loop-gravity transition amplitudes,
  Phys. Rev. D. 86 (2012), 124023, arXiv: 1207.6348.
• W. Wieland, Twistorial phase space for complex Ashtekar variables,
  Class. Quant. Grav. 29 (2012), 045007, arXiv: 1107.5002.
• W. Wieland, Complex Ashtekar variables and reality conditions for Holst's action,
  Annales Henri Poincaré 12 (2012), 425, arXiv: 1012.1738.
• W. Wieland, Twistor representation of Jackiw-Teitelboim gravity, arXiv: 2003.13887.
• E. Bianchi, W. Wieland, Horizon energy as the boost boundary term in general relativity and loop gravity, arXiv: 1205.5325.
• W. Wieland, Complex Ashtekar variables, the Kodama state and spinfoam gravity, arXiv: 1105.2330.

Seminars

• APS April Meeting 2018 (Columbus, Ohio), Loop Quantum Gravity and the Quantization of Null Surfaces , 2017-07-05, slides.
• New boundary variables for Classical and Quantum Gravity on a null surface, Seminar at IQOQI (Vienna, Austria), 2017-07-25.
• Loops'17 (Warsaw, Poland), New boundary variables for classical and quantum gravity, 2017-07-05, slides.
• Spinors as boundary variables for gravity on a null surface, Seminar of the Gravitational Physics Group at the University of Vienna, 2017-03-01.
• Spinors as boundary variables for gravity on a null surface, Seminar given at the Centre de Physique Théorique (Marseille, France), 2017-02-21.
• Four Lectures on non-perturbative quantum gravity, Lectures held at the Institute for Theoretical Physics at the University of Innsbruck, February 2017.
• Fifth Tux winter workshop on Quantum Gravity (Tux, Austria), Spinors as boundary variables for gravity on a null surface, 2017-02-21.
• Discrete Gravity as a topological field theory with defects, Seminar given at Louisiana State University (Baton Rouge, USA), November 2016.
• Quasilocal free energy: Positivity and monotonicity, Seminar given at Caltech, October 2016.
• PIRSA:19030081, PSI 2018/2019 - Explorations in Quantum Gravity - Lecture 14, 2019-03-21, PSI 2018/2019 - Explorations in Quantum Gravity (Dupuis)
• PIRSA:15090076, TBA, 2015-09-28, Renormalization in Background Independent Theories: Foundations and Techniques
• PIRSA:14110116, Worldline formalism for covariant loop gravity, 2014-11-06, Quantum Gravity
• PIRSA:14030088, A one-dimensional action for simplicial gravity in three dimensions, 2014-03-06, Quantum Gravity
• PIRSA:13070045, Spin Foams - 2, 2013-07-22, Loops 13
• PIRSA:12020129, Spinor Quantisation for Complex Ashtekar Variables, 2012-02-29, Quantum Gravity