# Astrid Eichhorn

### Research Interests

My research focuses on quantum gravity (mostly asymptotic safety).
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. As an example, 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, quantum gravity could provide a solution to questions of the standard model at high energies: For instance, conventional bounds on the Higgs mass can be relaxed, if (quantum-gravity induced) higher order operators are considered in the Higgs potential.
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: Most recently, I have, 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. 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.
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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 <a href="http://www.percacci.it/roberto/physics/as/seminars.html"> webpage</a>.
FAQs on asymptotic safety can be found <a href="http://www.percacci.it/roberto/physics/as/faq.html">here</a>.
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Renormalization Group approaches to quantum gravity (2014):
All talks from this meeting can be found <a href="http://perimeterinstitute.ca/conferences/renormalization-group-approaches-quantum-gravity">here</a>.
All talks from the "Experimental search for quantum gravity - the hard facts" conference (Oct. 2012) can be found in <a href= "http://www.pirsa.org/">PIRSA</a>.
The titles and abstracts of talks are also available at <a href= "https://www.perimeterinstitute.ca/conferences/experimental-search-quantum-gravity-hard-facts">this location</a>.

### Recent Publications

- The Planck scale, the Higgs mass and scalar dark matter, Astrid Eichhorn, Michael M. Scherer, Phys.Rev. D90 (2014) 025023, arXiv: 1404.5962
- Matter matters in asymptotically safe quantum gravity, Pietro Dona, Astrid Eichhorn, Roberto Percacci, Phys. Rev. D 89, 084035, arXiv: 1311.2898
- The spectral dimension in causal set quantum gravity, Astrid Eichhorn, Sebastian Mizera, Class.Quant.Grav. 31 (2014) 125007, arXiv: 1311.2530
- Continuum limit in matrix models for quantum gravity from the Functional Renormalization Group, Astrid Eichhorn, Tim Koslowski, Phys. Rev. D88 (2013), 084016, arXiv: 1309.1690
- Multicritical behavior in models with two competing order parameters, Astrid Eichhorn, David Mesterhazy, Michael M. Scherer, Phys. Rev. E88 (2013), 042141, arXiv: 1306.2952
- Probing the quantum nature of spacetime by diffusion, Gianluca Calcagni, Astrid Eichhorn, Frank Saueressig, Phys. Rev. D87 (2013) 12, 124028, arXiv: 1304.7247
- Faddeev-Popov ghosts in quantum gravity beyond perturbation theory, Astrid Eichhorn, Phys. Rev. D.87 (2013) 12, 124016, arXiv: 1301.0632
- On unimodular quantum gravity, Astrid Eichhorn, Class.Quant.Grav. 30 (2013), 115016, arXiv: 1301.0879
- Renormalization Flow of Axion Electrodynamics, Astrid Eichhorn, Holger Gies, Dietrich Roscher, Phys. Rev. D86 (2012), 125014, arXiv: 1208.0014
- Quantum-gravity induced matter self-interactions in the asymptotic-safety scenario, Astrid Eichhorn, Phys. Rev. D86 (2012), 105021, arXiv: 1204.0965
- Can we see quantum gravity? Photons in the asymptotic-safety scenario, Babette Doebrich, Astrid Eichhorn, JHEP 1206 (2012) 156, arXiv: 1203.6366
- Towards phase transitions between discrete and continuum quantum spacetime from the Renormalization Group, Astrid Eichhorn, Tim Koslowski, arXiv: 1408.4127
- 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]

### Seminars

- Does matter matter in quantum gravity?, IARD 2014, University of Connecticut
- Matter matters in asymptotically safe quantum gravity, Theory Canada 9, Waterloo
- 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 steps on the way to quantum gravity, seminar at the Niels-Bohr-Institute, Copenhagen
- Renormalization Group approaches to quantum gravity, DESY theory seminar
- On unimodular quantum gravity, GR 20, Warsaw
- Probing the quantum nature of gravity, Relativity Lunch, Imperial College
- A quantum gravity perspective on the cosmological constant, Tales of Lambda workshop, University of Nottingham
- What to expect from asymptotically safe quantum gravity, Theoretical Particle Physics Seminar, University of Sussex
- Probing the quantum nature of spacetime by diffusion, UK-QFT workshop, 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
- Asymptotic safety - a quantum field theory of gravity, defense of the research training group "quantum and gravitational fields", University of Jena
- Challenges for a UV completion of gravity, seminar at the University of Mainz
- 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