Particle Physics: From the Early Universe to the Large Hadron Collider
Lead Research Organisation:
University of Manchester
Department Name: Physics and Astronomy
Abstract
Particle physics is all about understanding the elementary building blocks of nature and their interactions. Over the years, physicists have developed the Standard Model of particle physics, which is extremely successful in describing a very wide range of natural phenomena from things as basic as how light works and why atoms form through to the complicated workings inside stars and the synthesis of nuclei in the first few minutes after the Big Bang. However, we know that the Standard Model is not the whole story for it leaves many questions unanswered. Our proposal focuses on these unanswered questions and the way that scientists hope to address them in the coming years using experiments like the Large Hadron Collider (LHC) or observations like those that will be made using the Planck satellite. At the LHC, physicists are searching for the Higgs boson, which represents our current best guess as to what is responsible for the origin of mass. They are also searching for a whole host of new particles such as those predicted by supersymmetry. If supersymmetry is discovered then it offers the hope also to explain the origin of the Dark Matter that makes up a large fraction of the material that is known to exist in the Universe. The scientists in our consortium will explore the theory of supersymmetry and dark matter. We will use data from experiments like the LHC to identify which of the many possible variants of supersymmetry are allowed by the data and to suggest new ways to explore those models in experiments. Any 'new physics' produced at the LHC will be produced as a result of smashing two protons into each other and that means they will be produced in a complicated environment, probably in association with 'jets' of other particles. Members of our consortium will explore how we can make use of these jets to learn more about the associated new physics: the better we understand the environment in which new physics occurs, the more we are able to learn about the new physics itself. This is a complicated business that often necessitates computer simulations of particle collisions. Our members are experts in these simulations and have plans on how the make them more accurate, which is necessary if we are to make the most of the exciting data from the LHC. The Standard Model of particle physics is also deficient when it comes to explaining the early history of the Universe, when it was hot and dense. The evidence is now very strong that the history began with an era of accelerating expansion, called inflation. We are experts on inflation and its consequences. Inflation makes the Universe featureless, except for quantum fluctuations which somehow grow, causing the density of matter and energy in the Universe to vary with position. These initially small variations grow to become observable effects. One effect is the formation of the billions of galaxies that populate the night sky. Another effect is to leave a tiny imprint on the cosmic microwave background radiation (CMB), a faint hum of microwave radiation in which the earth is bathed. The CMB will be studied in exquisite detail by the Planck satellite, which was launched in 2009. We hope to be at the forefront of interpreting the Planck data in the hope of pinning down which of the various theories of the early universe are ruled out and which remain viable. The deficiencies of the Standard Model extend still further for it does not explain the amount nor even the existence of ordinary matter. Our scientists will use this to constrain possible physics beyond the Standard Model and to do that they need to master the dynamics of the Universe shortly after the end of inflation. Last but not least, we hope to understand better the mysterious 'Dark Energy' that drives the current and future acceleration of the Universe: perhaps it is because Einstein's theory of gravity is not quite right and that is something we will explore.
Organisations
Publications
Morley T
(2018)
Vacuum polarization on topological black holes
in Classical and Quantum Gravity
Millington P
(2012)
Perturbative Non-Equilibrium Thermal Field Theory
Millington P
(2013)
Thermal field theory to all orders in gradient expansion
in Journal of Physics: Conference Series
Millington P
(2013)
Perturbative nonequilibrium thermal field theory
in Physical Review D
Millington P
(2013)
Thermal field theory to all orders in gradient expansion
Millington P
(2013)
Perturbative non-equilibrium thermal field theory to all orders in gradient expansion
in Physics Letters B
Mifsud J
(2017)
Probing the imprints of generalized interacting dark energy on the growth of perturbations
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2013)
Hemispherical power asymmetry from scale-dependent modulated reheating
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2016)
The 750 GeV resonance as non-minimally coupled inflaton: Unitarity violation and why the resonance is a real singlet scalar
in Physics Letters B
McDonald J
(2015)
A minimal sub-Planckian axion inflation model with large tensor-to-scalar ratio
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2013)
Explaining the dark energy, baryon and dark matter coincidence via domain-dependent random densities
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2015)
Signatures of Planck corrections in a spiralling axion inflation model
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2016)
Nonminimally coupled inflation with initial conditions from a preinflation anamorphic contracting era
in Physical Review D
McDonald J
(2014)
Negative running of the spectral index, hemispherical asymmetry and the consistency of Planck with large r
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2016)
Warm dark matter via ultra-violet freeze-in: reheating temperature and non-thermal distribution for fermionic Higgs portal dark matter
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2014)
Sub-Planckian two-field inflation consistent with the Lyth bound
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2014)
Hemispherical power asymmetry from a space-dependent component of the adiabatic power spectrum
in Physical Review D
McDonald J
(2013)
Isocurvature and curvaton perturbations with red power spectrum and large hemispherical asymmetry
in Journal of Cosmology and Astroparticle Physics
McDonald J
(2012)
Simultaneous Generation of WIMP Miracle-like Densities of Baryons and Dark Matter
in Journal of Physics: Conference Series
McDonald J
(2013)
Baryon-to-dark matter ratio from random angular fields
in Journal of Cosmology and Astroparticle Physics
Mazumdar A
(2015)
Possible resolution of the domain wall problem in the NMSSM
Mazumdar A
(2014)
Dynamical breaking of shift-symmetry in supergravity-based inflation
Description | Progress on many fronts towards a better understanding of the universe, by developing theoretical models constrained by data from the LHC and cosmology experiments such as Planck. |
Exploitation Route | By continued research. |
Sectors | Education |
Description | Researchers supported by this award have been very active in outreach activities for the general public, schools and scientists from other fields. |
First Year Of Impact | 2014 |
Sector | Education |
Impact Types | Cultural,Societal |