Astrid Eichhorn

Astrid Eichhorn's picture
Phd: Theoretisch Physikalisches Institut, Friedrich-Schiller Universitaet Jena 2011

Area of Research:
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.

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, in collaboration with P. Dona and R. Percacci, that not all matter models are consistent with asymptotically safe quantum gravity.
Further, I have, in collaboration with M. Scherer, addressed the question whether higher-order operators, as are indeed expected from asymptotic safety, could relax conventional bounds on the Higgs mass, and lead to a compatibility between the measured value of the Higgs mass and the validity of the Standard Model all the way to the Planck scale.

A second main aspect of my work in quantum gravity is the development of Renormalization Group tools for different quantum gravity models. Together with T. Koslowski, I have developed a Renormalization Group equation that can be used to search for the continuum limit in discrete models of spacetime, such as matrix and tensor models.

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 together with S. Mizera 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. Together with D. Mesterhazy and M. Scherer, I have applied the Functional RG to the study of such systems with two or more competing order parameters.

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.

Renormalization Group approaches to quantum gravity (2014):
All talks from this meeting can be found here.

Experimental search for quantum gravity - the hard facts (2012):

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

  • The%20Planck%20scale%2C%20the%20Higgs%20mass%20and%20scalar%20dark%20matter%2C%20Astrid%20Eichhorn%2C%20Michael%20M.%20Scherer%2C%20Phys.Rev.%20D90%20(2014)%20025023%2C%20arxiv%3A1404.5962
  • The Planck scale, the Higgs mass and scalar dark matter, Astrid Eichhorn, Michael M. Scherer, Phys.Rev. D90 (2014) 025023, arXiv: 1404.5962
  • The spectral dimension in causal set quantum gravity, Astrid Eichhorn, Sebastian Mizera, Class.Quant.Grav. 31 (2014) 125007, arXiv: 1311.2530
  • The%20spectral%20dimension%20in%20causal%20set%20quantum%20gravity%2C%20Astrid%20Eichhorn%2C%20Sebastian%20Mizera%2C%20Class.Quant.Grav.%2031%20(2014)%20125007%2C%20arxiv%3A1311.2530
  • Matter%20matters%20in%20asymptotically%20safe%20quantum%20gravity%2C%20Pietro%20Dona%2C%20Astrid%20Eichhorn%2C%20Roberto%20Percacci%2C%20Phys.%20Rev.%20D%2089%2C%20084035%2C%20arxiv%3A1311.2898
  • Matter matters in asymptotically safe quantum gravity, Pietro Dona, Astrid Eichhorn, Roberto Percacci, Phys. Rev. D 89, 084035, arXiv: 1311.2898
  • Multicritical%20behavior%20in%20models%20with%20two%20competing%20order%20parameters%2C%2C%20Astrid%20Eichhorn%2C%20David%20Mesterhazy%20and%20Michael%20M.%20Scherer%2C%20Phys.%20Rev.%20E%2088%2C%20042141%20(2013)%2C%0A%20%20arXiv%3A1306.2952%20%5Bcond-mat.stat-mech%5D.
  • Continuum%20limit%20in%20matrix%20models%20for%20quantum%20gravity%20from%20the%20Functional%20Renormalization%20Group%2C%20Astrid%20Eichhorn%20and%20Tim%20Koslowski%2C%0APhys.%20Rev.%20D%2088%2C%20084016%20(2013)%2C%0AarXiv%3A1309.1690%20%5Bgr-qc%5D.
  • Probing%20the%20quantum%20nature%20of%20spacetime%20by%20diffusion%2C%20%0A%20Gianluca%20Calcagni%2C%20Astrid%20Eichhorn%20and%20Frank%20Saueressig%2C%0APhys.%20%20Rev.%20%20D%2087%2C124028%20(2013)%0A%20%20%5BarXiv%3A1304.7247%20%5Bhep-th%5D%5D.
  • Faddeev-Popov%20ghosts%20in%20quantum%20gravity%20beyond%20perturbation%20theory%2C%20%0AAstrid%20Eichhorn%2C%20Phys.%20Rev.%20D.87.124016%2C%20(2013)%0AarXiv%3A1301.0632
  • On%20unimodular%20quantum%20gravity%2C%20Astrid%20Eichhorn%2C%20Class.Quant.Grav.%2030%20(2013)%20115016%2C%20arXiv%3A1301.0879
  • Renormalization%20Flow%20of%20Axion%20Electrodynamics%2C%20Astrid%20Eichhorn%2C%20Holger%20Gies%20and%20Dietrich%20Roscher%2C%20Phys.Rev.%20D86%20(2012)%20125014%2C%20%20arXiv%3A1208.0014%20%5Bhep-ph%5D
  • Quantum-gravity-induced%20matter%20self-interactions%20in%20the%20%20asymptotic-safety%20scenario%2C%20Astrid%20Eichhorn%2CPhys.Rev.%20D86%20(2012)%20105021%2C%20%20arxiv%3Agr-qc%2F1204.0965
  • Can%20we%20see%20quantum%20gravity%3F%20Photons%20in%20the%20asymptotic-safety%20scenario%2C%20Babette%20D%f6brich%2C%20Astrid%20Eichhorn%2C%20JHEP%201206%20(2012)%20156%2C%20arxiv%3Agr-qc%2F1203.6366
  • Generalized critical behavior in multi-field models, Astrid Eichhorn, David Mesterhazy, Michael M. Scherer, arXiv: 1407.7442
  • Experimentally testing asymptotically safe quantum gravity with photon-photon scattering. Proceedings of the 13th Marcel Grossmann Meeting, Stockholm. arXiv: 1210.1528 [hep-th]


  • Matter matters in asymptotically safe quantum gravity, Theory Canada 9, Waterloo
  • Does matter matter in quantum gravity?, IARD 2014, University of Connecticut
  • Renormalization Group steps on the way to quantum gravity, seminar at AEI, Golm
  • Asymptotic safety - a testable theory of quantum gravity? seminar at the University of Illinois, Chicago
  • Renormalization Group steps on the way to quantum gravity, theory seminar at the University of Heidelberg
  • Renormalization Group approaches to quantum gravity, DESY theory seminar
  • Renormalization Group steps on the way to quantum gravity, seminar at the Niels-Bohr-Institute, Copenhagen
  • On unimodular quantum gravity, GR 20, Warsaw
  • 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
  • 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
  • A fixed point for unimodular quantum gravity, Quantum gravity workshop, University of Heidelberg
  • Unimodularity, ghosts and matter in asymptotically safe quantum gravity, seminar at the University of Nijmegen
  • 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
  • PIRSA:14050125, Asymptotic safety - a quantum theory of gravity and matter, 2014-05-21, Quantum Gravity Day 2014
  • PIRSA:14040109, Why matter matters in quantum gravity, 2014-04-25, Renormalization Group Approaches to Quantum Gravity
  • PIRSA:13070073, Phenomenology - 3, 2013-07-25, Loops 13
  • PIRSA:12100121, Effective field theory framework in QG, 2012-10-25, Experimental Search for Quantum Gravity 2012
  • PIRSA:12100104, Dynamical Dimensional Reduction, 2012-10-24, Experimental Search for Quantum Gravity 2012
  • PIRSA:11100112, Science in the Pub - How Does Science Work?, 2011-10-18, Experimental Search for Quantum Gravity 2012
  • PIRSA:10120025, Aspects of confinement from the functional Renormalization Group, 2010-12-01, Quantum Gravity