Quantum Gravity

Find here an overview of my Quantum Gravity related publications, invited talks and general talks.

Publications

My publication list can also be found on Inspire, arXiv. (Authors in alphabetical order as customary in the QG community)

2022

23. “Quantum speed limit and stability of coherent states in quantum gravity” – K. Liegener, Ł. Rudnicki, Class. Quant. Grav. 39, 12 arXiv:2112.01597

22. “Towards exploring features of Hamiltonian Renormalisation relevant for quantum gravity” – B. Bahr, K. Liegener, Class. Quant. Grav. 39, 7 arXiv:2101.02676

2021

21. “Algorithmic approach to Cosmological Coherent State Expectation Values in LQG” – K. Liegener, Ł. Rudnicki, Class. Quant. Grav. 38, 20 arXiv:2012.07813

20. “Symmetry restriction and its application to gravity” – W. Kaminski, K. Liegener, Class. Quant. Grav. 38, 6 arXiv:2009.06311

19. “Hamiltonian Renormalisation V: Free Vector Bosons” – K. Liegener, T. Thiemann, Front. Astron. Space Sci., 7 arXiv:2003.13059

2020

18. “Modifications to gravitational wave equation from canonical quantum gravity” – A. Dapor, K. Liegener, EPJC Letter, 80, 741 arXiv:2002.00834

17. “Effective LQC model for k=+1 isotropic cosmology from discrete spacetimes” – K. Liegener, S. Weigl, Phys. Rev. D, 102 arXiv:2001.00031

16. “Expectation values of Coherent States for SU(2) Lattice Gauge Theories” – K. Liegener, E. Zwicknagel, Journal of High Energy Physics, 24 arXiv:2001.00032

2019

15. “Challenges in recovering a consistent cosmology from the effective dynamics of loop quantum gravity” – A. Dapor, K. Liegener, T. Pawłowski, Phys. Rev. D., 100 arXiv:1910.04710

14. “Some physical implications of regularization ambiguities in SU(2) gauge-invariant loop quantum cosmology” – K. Liegener, P. Singh, Phys. Rev. D., 100 arXiv:1908.07543

13. “New Loop Quantum Cosmology Modifications from Gauge-covariant Fluxes” – K. Liegener, P. Singh, Phys. Rev. D 100 arXiv:1908.07001

12. “Perspectives on the dynamics in loop effective black hole interior” – M. Assanioussi, A. Dapor, K. Liegener, Phys. Rev. D 100 arXiv:1908.05756

11. “Emergent de Sitter epoch of the Loop Quantum Cosmos: detailed analysis” – M. Assanioussi, A. Dapor, K. Liegener, T. Pawłowski, Phys. Rev. D 100 arXiv:1906.05315

10. “Gauge invariant bounce from quantum geometry” – K. Liegener, P. Singh, Class. Quant. Grav., 37, 8 arXiv:1906.02759

2018

9. “Emergent de Sitter Epoch of the Quantum Cosmos” – M. Assanioussi, A. Dapor, K. Liegener, T. Pawłowski, Phys. Rev. Lett. 121,8 arXiv:1801.00768

10. “Hamiltonian renormalisation IV. Renormalisation flow of D + 1 dimensional free scalar fields and rotation invariance” – T. Lang, K. Liegener, T. Thiemann, Class. Quant. Grav. 35, 24 arXiv:1711.05695

11. “Hamiltonian renormalization III. Renormalisation flow of 1 + 1 dimensional free scalar fields: properties” – T. Lang, K. Liegener, T. Thiemann, Class. Quant. Grav. 35, 24 arXiv:1711.05688

12. “Hamiltonian Renormalisation II. Renormalisation Flow of 1+1 dimensional free scalar fields: Derivation” – T. Lang, K. Liegener, T. Thiemann, Class. Quant. Grav. 35, 24 arXiv:1711.06727

13. “Hamiltonian Renormalisation I: derivation from Osterwalder–Schrader reconstruction” – T. Lang, K. Liegener, T. Thiemann, Class. Quant. Grav. 35, 24 arXiv:1711.05685

14. “Cosmological coherent state expectation values in loop quantum gravity I. Isotropic kinematics” – A. Dapor, K. Liegener, Class. Quant. Grav. 35, 13 arXiv:1710.04015

2017

3. “Cosmological Effective Hamiltonian from full Loop Quantum Gravity Dynamics” – A. Dapor, K. Liegener, Phys. Lett. B785, 506 arXiv:1710.04015

2016

2. “Towards the fundamental spectrum of the Quantum Yang-Mills Theory” – K. Liegener, T. Thiemann, Phys. Rev. D 94 arXiv:1605.05975

2013

1. “Matrix Elements of Lorentzian Hamiltonian Constraint in LQG” – E. Alesci, K. Liegener, A. Zipfel, Phys. Rev. D 88 arXiv:1306.0861

Invited Talks

• “Loop Quantum Gravity and its road to phenomenology” (13/07/2022) at COST CA18108 Third Annual Conference, Napoli, Italy.

• [Virtual] “Towards semi-classical cosmology in LQG” (21/01/2022) at Gravity Seminar, Warsaw university, Poland, YouTube.

• “Finding the correct Dynamics in LQG” (18/01/2019), Florida Atlantic University, Boca Raton, US.

• “Hamiltonian Approach to gauge-invariant Einstein-Yang-Mills Theory” (19/12/2017), Quantum Seminar, Regensburg, Germany.

Talks

• [Virtual] “Semi-classical limit of LQG and the Quantum Speed Limit” (02/2022) at 8th Tux Workshop, Austria.

• [Virtual] “Effective Loop Models from spatial discretisation” (26/03/2021) at York University, Toronto, Canada.

• [Virtual] “A Hamiltonian verion of the Renormalisation Group - Part I-III” (07-14/07/2022) at Discrete Quantum Gravity Seminar, Hamburg, Germany.

• [Virtual] “Hamiltonian Renormalisation and its Application to Quantum Gravity” (19/03/2020) at Friedrich-Schiller University, Jena, Germany.

• “Current Status and Prospects for Lattice LQG” (04/12/2019) at IQG Seminar, Erlangen, Germany.

• “An Algorithm for LQG Expectation Values in Cosmology” (17/06/2019) at LOOPS 19 conference, Pennsylvania State University, USA.

• “New LQC Modifications from Symplectic Structures” (17/06/2019) at LOOPS 19 conference, Pennsylvania State University, USA.

• [Virtual] “New LQC Modifications from Symplectic Structures” (14/05/2019) at International Loop Quantum Gravity Seminar.

• “Discretisation Ambiguities in (Loop) Quantum Gravity” (06/07/2018) at 15th Marcel Grossmann meeting, Rome, Italy.

• “Hamiltonian Renormalisation” (19/02/2018) at Tux workshop on quantum gravity, Tux, Austria.

• [Virtual] “Cosmological Effective Hamiltonian from full LQG” (26/09/2017) at International Loop Quantum Gravity Seminar.

• “Cosmological Effective Hamiltonian from full LQG Dynamics” (17/07/2017) at LOOPS 17 conference, Warsaw, Poland.

• “Quantum Einstein Yang-Mills theory in Loop Quantum Gravity” (26/06/2016) at Classical and Quantum Symmetries conference, Jena, Germany.

• “Towards the Quantum Einstein Yang-Mills Spectrum” (29/02/2016) at Spring conference, German Physical Society, Hamburg, Germany.