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Astrid Eichhorn

Portrait de Astrid Eichhorn
Phd: Theoretisch Physikalisches Institut, Friedrich-Schiller Universitaet Jena 2011

Area of Research:
Email: aeichhorn@perimeterinstitute.ca
Phone: x6254

Research Interests

My research focuses on quantum gravity.
I'm mostly working on asymptotically safe quantum gravity, which is a continuum QFT approach to quantum gravity within the path-integral framework. My interest lies in two aspects, namely, a better understanding of the quantum gravity theory, as well as a route towards a more realistic model, that includes matter degrees of freedom and could potentially lead to experimental detection of quantum gravity.
Recently, I have studied a unimodular version of asymptotic safety, and shown that it shows an interacting fixed point for the Newton coupling, and could therefore exist as a quantum theory, which provides a solution to the cosmological constant fine-tuning problem.

A main research goal of mine is to establish a bridge between quantum gravity and particle physics. This can provide a way to test quantum gravity on the one hand, and provide an ultraviolet completion for the Standard Model of particle physics on the other hand. As an example of the former, I have recently shown that not all matter models are consistent with asymptotically safe quantum gravity.

I have also worked on the question of dimensional flow in different quantum gravity models, and studied how one can derive that the spectral dimension goes to 2 in the UV in different models, based on well-defined diffusion processes that probe the quantum spacetime. I have also extended this tool to a Lorentzian setting and shown that there is a dimensional increase of the spectral dimension in causal set quantum gravity.

More recently, I've also become interested in systems that have phase diagrams which are governed by competing order parameters, and can show multicritical points. The Functional Renormalization Group is very well-adapted to the study of such systems, which involve antiferromagnets in an external magnetic field, high-Tc superconductors, and a variety of other materials.

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The International Seminar on Asymptotic Safety:

If you're interested in the International Seminar on Asymptotic Safety (held via skype), please send me an email.
Details on the seminar, and slides of the previous talks can be found at Roberto Percacci's webpage.
FAQs on asymptotic safety can be found here.


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Experimental search for quantum gravity - the hard facts:

All talks from the "Experimental search for quantum gravity - the hard facts" conference (Oct. 2012) can be found in PIRSA.
The titles and abstracts of talks are also available at this location.

Recent Publications

  • Continuum limit in matrix models for quantum gravity from the Functional Renormalization Group, Astrid Eichhorn and Tim Koslowski, Phys. Rev. D 88, 084016 (2013), arXiv: 1309.1690 [gr-qc].
  • Multicritical behavior in models with two competing order parameters,, Astrid Eichhorn, David Mesterhazy and Michael M. Scherer, Phys. Rev. E 88, 042141 (2013), arXiv: 1306.2952 [cond-mat.stat-mech].
  • Probing the quantum nature of spacetime by diffusion, Gianluca Calcagni, Astrid Eichhorn and Frank Saueressig, Phys. Rev. D 87,124028 (2013) [arXiv: 1304.7247 [hep-th]].
  • On unimodular quantum gravity, Astrid Eichhorn, Class.Quant.Grav. 30 (2013) 115016, arXiv: 1301.0879
  • Faddeev-Popov ghosts in quantum gravity beyond perturbation theory, Astrid Eichhorn, Phys. Rev. D.87.124016, (2013) arXiv: 1301.0632
  • Renormalization Flow of Axion Electrodynamics, Astrid Eichhorn, Holger Gies and Dietrich Roscher, Phys.Rev. D86 (2012) 125014, arXiv: 1208.0014 [hep-ph]
  • Quantum-gravity-induced matter self-interactions in the asymptotic-safety scenario, Astrid Eichhorn,Phys.Rev. D86 (2012) 105021, arxiv:gr-qc/1204.0965
  • Can we see quantum gravity? Photons in the asymptotic-safety scenario, Babette Döbrich, Astrid Eichhorn, JHEP 1206 (2012) 156, arxiv:gr-qc/1203.6366
  • Astrid Eichhorn, Sebastian Mizera, ``Spectral dimension in causal set quantum gravity", arXiv: 1311.2530 [gr-qc]
  • Pietro Dona, Astrid Eichhorn, Roberto Percacci, ``Matter matters in asymptotically safe quantum gravity" arXiv: 1311.2898 [hep-th]
  • Experimentally testing asymptotically safe quantum gravity with photon-photon scattering. Proceedings of the 13th Marcel Grossmann Meeting, Stockholm. arXiv: 1210.1528 [hep-th]

Seminars

  • A quantum gravity perspective on the cosmological constant, Tales of Lambda workshop, University of Nottingham
  • Probing the quantum nature of gravity, Relativity Lunch, Imperial College
  • On unimodular quantum gravity, GR 20, Warsaw
  • Probing the quantum nature of spacetime by diffusion, UK-QFT workshop, University of Sussex
  • What to expect from asymptotically safe quantum gravity, Theoretical Particle Physics Seminar, University of Sussex
  • Probing the quantum nature of spacetime, Astrophysics Seminar, Nordita, Stockholm
  • On unimodular quantum gravity, APS April meeting, Denver, CO
  • Unimodularity, ghosts and matter in asymptotically safe quantum gravity, seminar at the University of Nijmegen
  • A fixed point for unimodular quantum gravity, Quantum gravity workshop, University of Heidelberg
  • Challenges for a UV completion of gravity, seminar at the University of Mainz
  • Asymptotic safety - a quantum field theory of gravity, defense of the research training group "quantum and gravitational fields", University of Jena
  • Matter in asymptotically safe quantum gravity, plenary talk at 6th ERG conference, Aussois, France
  • Matter in asymptotically safe quantum gravity, 13th Marcel Grossmann Meeting, Stockholm
  • Asymptotic safety - a quantum field theory of gravity and matter?, DESY theory seminar, Hamburg
  • Matter in asymptotically safe quantum gravity, CAP congress, Calgary