Physics of the Early Universe

Module overview

Since the end of the 1990s, cosmology has experienced one of the most impressive advances among all scientific disciplines. This happened mainly because of astonishing progress in the precision and accuracy of astronomical and cosmological observations resulting in a breathtaking sequence of major scientific discoveries as witnessed by two Nobel Prizes in Physics awarded in this period for discoveries in cosmology: in 2006 to G.F.Smoot and J.C.Mather for the discovery of the cosmic microwave background radiation anisotropy and in 2011 to S.Perlmutter, B.S.Schmidt and A.G.Riess for the discovery of the accelerating expansion of the universe through observations of distant supernovae.

It is now established that the universe experienced an early hot stage where particle physics greatly influenced the properties of the universe and its evolution: this is the early universe stage. This allows to use the universe as a special laboratory of particle physics, double checking results that we found in ground laboratories but even more importantly probing new physics, i.e., physics beyond the Standard Model. Even more excitingly we arrived to the conclusion that today cosmological observations can be only explained extending the Standard Model and, therefore, cosmology represents today one of the greats motivations for beyond the standard model physics. In the module established results, such as recombination and big bang nucleosynthesis, will be discussed together with the solutions to these challenging cosmological puzzles that require new physics.

Linked modules

Pre-requisite: PHYS3007

Aims and Objectives

Learning Outcomes

Having successfully completed this module you will be able to:

Understand main models of Dark Matter
Understand the main physical processes that lad to the formation of perturbations during inflation and how these evolve forming the large scale structure of the universe we observe
Understand how kinetic theory is applied in the early universe
Understand the physics of Big Bang Nucleosynthesis
Understand how particle physics influence the properties of radiation dominated regime
Understand the main processes during recombination and how these lead to the formation of CMB with the properties we observe
Understand key features in models of dark energy
Be able to discuss main features of Friedmann cosmology.
Be able to relate matter antimatter asymmetry of the universe to particle physics with baryogenesis models
Calculate the number of radiation degrees of freedom in the Standard Model
Understand the motivations for inflation and how this solves horizon and flatness problems
Understanding interplay of cosmological constant and standard fluids in Lemaitre cosmological models

Learning and Teaching

Teaching and learning methods

The module will be based on lectures in class with deviation of main results on black board with auxiliary slides to show plots, pictures , summarise results. There will be 3 hours of lectures per week for a total of 36 hours.

Study time
Type	Hours
Completion of assessment task	2
Wider reading or practice	66
Preparation for scheduled sessions	18
Follow-up work	18
Revision	12
Lecture	36
Total study time	152

Assessment

Assessment strategy

There will be 11 problem sheets handed out on weekly basis. Although these do not count towards the final mark, they should provide useful feedback to students since detailed model answers will be posted the subsequent week. Some of the problems will be discussed in class. Notice also that a test will take place during the second hour of week 9. Though it will not contribute to the final mark, it will be marked. Results will be made available in week 11 and will provide a useful individual feedback before the final exam.

Summative

This is how we’ll formally assess what you have learned in this module.

Breakdown
Method	Percentage contribution
Final Assessment	88%
Assignments and problem sheets	12%

Referral

This is how we’ll assess you if you don’t meet the criteria to pass this module.

Breakdown
Method	Percentage contribution
Final Assessment	88%
Assignments and problem sheets	12%

Repeat

An internal repeat is where you take all of your modules again, including any you passed. An external repeat is where you only re-take the modules you failed.

Breakdown
Method	Percentage contribution
Final Assessment	88%
Assignments and problem sheets	12%

Repeat Information

Repeat type: Internal & External