**Quantum field theories of the dark universe group**

**Based primarily in the Particle Theory Group, Department of Physics and Astronomy, The University of Manchester, UK**

**Welcome to our group website.**

Our aim is to understand the fundamental natures of dark matter and dark energy . Together, these ingredients make up 95% of the energy density of our universe, and yet we do not know the origins of this dark universe in terms of elementary particles or forces.

We are not doing this on our own though. We are playing our part in global efforts to uncover the mysteries of the dark universe, one of the most challenging outstanding problems in modern physics.

Our focus is the applications of powerful mathematical frameworks, including quantum field theory , which allow us to describe how subatomic particles move and interact with one another at the microscopic level. This allows us to make predictions of what theories of dark matter and dark energy mean for astrophysics, cosmology, gravitation and particle physics.

Take a look at our blog to see what we are up to, or watch our videos (coming soon). If you are a scientist (or a budding one), please take a look at our papers. And if you have questions, please get in touch.

**Thank you for visiting.**

**Our News**

#### Welcome back to our new website! Sorry we have been away, but we were moving home to the University of Manchester! Please bear with us while we keep working on the content.

**Our Team**

**Maxim Chernodub**

**Visitor**

Maxim is a CNRS Senior Scientist (Directeur de recherche) at the Institut Denis Poisson, Université de Tours, France, working on quantum chromodynamics, the Casimir effect, lattice gauge theory and anomalous transport effects.

**Yannick Kluth**

**Research Associate**

Yannick is a Postdoctoral Research Associate at the University of Manchester, specialising in the exact renormalisation group.

**Andrei Lazanu**

**Research Associate**

Andrei is a Postdoctoral Research Associate at the University of Manchester, specialising in early Universe probes of scalar-tensor theories of gravity.

**Group Leader**

Pete is a UKRI Future Leaders Fellow and Senior Research Fellow at the University of Manchester, specialising in applications of quantum field theory to particle physics and cosmology.

**Esra Sablevice**

**PhD Student**

Esra is a third-year PhD student at the University of Manchester, working on non-Hermitian quantum field theories.

**Michael Udemba**

**PhD Student**

Michael is a second-year PhD student at the University of Manchester, working on semi-classical approaches in quantum field theory.

**Our Papers**

##### A DHOST model of inflation: CMB constraints from the power spectrum and the bispectrum

J. I. McDonald and P. Millington

##### A DHOST model of inflation: CMB constraints from the power spectrum and the bispectrum

Andrei Lazanu

##### Anomalous dispersion, superluminality, and instabilities in two-flavor theories with local non-Hermitian mass mixing

Maxim N. Chernodub and Peter Millington

##### Robustness of the derivative expansion in Asymptotic Safety

Alessio Baldazzi, Kevin Falls, Yannick Kluth, and Benjamin Knorr

##### Renormalization group flows from the Hessian geometry of quantum effective actions

Yannick Kluth, Peter Millington and Paul M Saffin

##### CMB bispectrum constraints on DHOST inflation

Wuhyun Sohn, Andrei Lazanu, Philippe Brax and James R. Fergusson

##### Flavour oscillations in pseudo-Hermitian quantum theories

Robert Mason, Peter Millington, and Esra Sablevice

##### Higgs-Induced Screening Mechanisms in Scalar-Tensor Theories

Clare Burrage and Peter Millington

##### Terrestrial Very-Long-Baseline Atom Interferometry: Workshop Summary

Peter Millington et al.

##### Poincaré symmetries and representations in pseudo-Hermitian quantum field theory

Esra Sablevice and Peter Millington

##### Axion-Photon Conversion in 3D Media and Astrophysical Plasmas

J. I. McDonald, B. Garbrecht and P. Millington

##### Environmental sustainability in basic research - A perspective from HECAP+

Sustainable HECAP+ Initiative

##### Oscillation probabilities for a PT-symmetric non-Hermitian two-state system

Jean Alexandre, Madeleine Dale, John Ellis, Robert Mason and Peter Millington

**FeynMG: a FeynRules extension for scalar-tensor theories of gravity**

Sergio Sevillano Muñoz, Edmund J. Copeland, Peter Millington and Michael Spannowsky

**Vertex functions and their flow equations from the 2PI effective action**

Peter Millington and Paul M. Saffin

**Discrete spacetime symmetries, second quantization and inner products in a non-Hermitian Dirac fermionic field theory**

Jean Alexandre, John Ellis and Peter Millington

##### Fifth forces and broken scale symmetries in the Jordan frame

Edmund J. Copeland, Peter Millington and Sergio Sevillano Muñoz

##### EuCAPT White Paper: Opportunities and Challenges for Theoretical Astroparticle Physics in the Next Decade

R. Alves Batista *et al*.

##### IR/UV mixing from local similarity maps of scalar non-Hermitian field theories

Maxim N. Chernodub and Peter Millington

##### Benchmarking regulator-sourced 2PI and average 1PI flow equations in zero dimensions

Peter Millington and Paul M. Saffin

##### Fifth-force screening around extremely compact sources

Clare Burrage, Benjamin Elder, Peter Millington, Daniela Saadeh and Ben Thrussel

##### Statistics on Lefschetz thimbles: Bell/Leggett-Garg inequalities and the classical-statistical approximation

Peter Millington, Zong-Gang Mou, Paul M. Saffin and Anders Tranberg

##### Discrete spacetime symmetries and particle mixing in non-Hermitian scalar quantum field theories

Jean Alexandre, John Ellis and Peter Millington

**Our Codes**

**FeynMG**

Sergio Sevillano Muñoz, Edmund J. Copeland, Peter Millington and Michael Spannowsky

FeynMG is a Mathematica package to manipulate scalar tensor theories of gravity into a form that can be processed within the FeynRules framework.

**Our Engagements**

##### Talk at UK QFT XI, University of Cambridge

Sergio Sevillano Muñoz

9 January 2023; talk "How to find the Feynman Rules from any scalar-tensor theory and not collapse in the process".

##### Talk at Nottingham Centre of Gravity

Sergio Sevillano Muñoz

16 December 2022; talk "Addressing the Hubble tension with scalar fields".

##### Seminar at the Institute for Particle Physics Phenomenology (IPPP), Durham University

Peter Millington

27 December 2021; invited seminar (online) "Second quantization in non-Hermitian field theories" at the Institute for Particle Physics Phenomenology (IPPP), Durham University, UK.

##### Fifth forces in scalar-tensor theories and how to avoid them

Sergio Sevillano Muñoz

16 December 2021; talk (online) "Fifth forces in scalar-tensor theories and how to avoid them" at the YTF 2021, hosted by the Institute for Particle Physics Phenomenology (IPPP), Durham University, UK.

##### Seminar at the Korea Institute for Advanced Study

Peter Millington

7 December 2021; invited seminar (online) "Non-Hermiticity: a new paradigm for model building in particle physics" at the Korea Institute for Advanced Study (KIAS), Seoul, Korea.

##### Parallel talk at EPS-HEP 2021

Peter Millington

29 July 2021; parallel talk (online) "Non-Hermiticity: a new paradigm for model building in particle physics" at the European Physical Society Conference on High Energy Physics 2021 (EPS-HEP 2021), organised by the Universtät Hamburg and DESY.

##### Seminar at the Dublin Institute for Advanced Studies

Peter Millington

5 May 2021; invited seminar (online) "Non-Hermiticity: a new paradigm for model building in particle physics" at the Dublin Institute for Advanced Studies, Ireland.

##### Plenary talk at Non-Hermitian Physics 2021

Peter Millington

22 March 2021; plenary talk (online) at Non-Hermitian Physics 2021, hosted by the International Centre for Theoretical Sciences of the Tata Institute of Fundamental Research, Bengularu, India.

##### Plenary talk at ERG2020

Peter Millington

2 November 2020; plenary talk (online) "An alternative flow equation from the regulator-sourced 2PI effective action" at the 10th International Conference on

Exact Renormalization Group 2020 (ERG2020), hosted by the Yukawa Institute for Theoretical Physics, Kyoto University, Japan.

**Our Outreach**

##### North West Science Network

Peter Millington

20 January 2021; schools talk "Space, time and quantumness" for the North West Science Network.

##### Toot Hill School

Peter Millington

10 November 2021; schools talk "Big Bangs: smashing particles and our teenage universe" at Toot Hill School, Bingham, Nottinghamshire.

**Our Connections**

The affiliations of our collaborators, past and present.

**Accessibility**

We are committed to equality, diversity, inclusivity and accessibility. If you think we are falling short, and the accessibility of this website or its content can be improved, please get in touch so that we can do better.

**Sustainability**

We are committed to improving the environmental sustainability of our research.

Where possible, external collaborations are maintained virtually. When it is essential to meet collaborators in person, e.g., to address particularly tricky aspects of a problem, we are in favour of “slow travel”. This means that we take the train instead of the plane when we can, or make longer trips when feasible.

**Our Funders**

Quantum field theories of the dark universe

Grant No.: MR/V021974/1 (previous) and MR/V021974/2 (current); PI: Peter Millington

##### UKRI (United Kingdom Research and Innovation)

Dark Energy and the Cosmological Constant, University of Nottingham

Ref.: 2429865; PI: Edmund J. Copeland

##### STFC (Science and Technology Facilities Council)

Connecting particle physics and modified gravity through Higgs portals

PI: Peter Millington

##### IPPP (Institute for Particle Physics Phenomenology)

**Opportunities**

For details of current postgraduate study opportunities, see the University of Manchester Particle Physics Group webpage.

**Get in Touch**

Contact details for University of Manchester members can be found via the Particle Physics Group contacts page.

**Privacy and GDPR**

This page is maintained by Peter Millington. Copyright © 2023 QFT in the Dark.