Course-PM

Standard model of particle physics

TIF355 / FYM355   (Chalmers U./Gothenburg U.)  lp1 HT24 (7.5 hp) 

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In this page you find most of the information needed about the course. There may be small additions/adjustments as we go along. In doubt, drop me en email.

Contact details

Examiner/lecturer:  Gabriele Ferretti  (ferretti@chalmers.se)

Can be found in Origo room 6111. Tel. 031-772 3157. Mobile: 0721582259

Office Hours

Come to my office on these times. (Origo 6th floor, room 6111. If there are too many of you, I booked room 6115 next door). I'll try to leave the corridor door unlocked, but I will forget. Call me in that case. There are two "passes": 13:15-15:00 and 15:15-17:00
If you are interested, come at the beginning, so if there is nobody, I know I can do something else. I am also able to stay after class most of the time.

Student representatives

tomas.baltazar@tecnico.ulisboa.pt       Tomás Di Paolo Baltazar 

samueled@chalmers.se    Samuel Edlund

oscar.alkeskog@gmail.com        Oscar Fagrell Alkeskog

rodung@student.chalmers.se      Ludvig Rodung

arvidryberg.98@gmail.com        Arvid Ryberg

Prerequisites (important!)

The prerequisites for this course are any introductory course in quantum field theory where

1- you have seen the QED lagrangian

\(-\frac{1}{4} F_{\mu\nu} F^{\mu\nu} + \bar\psi (i \gamma^\mu D_\mu - m)\psi\)$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$$-\frac{1}{4}{F}_{\mu \nu }{F}^{\mu \nu }+\overline{\psi }(i{\gamma }^{\mu }{\mathrm{\partial }}_{\mu }-m)\psi$

2- you have derived its Feynman rules and

3- you have computed at least one elementary process, e.g. the Möller scattering  cross section for

\(e^-\, e^- \to e^- \, e^-\)$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$$e^{-}{e}^{-}\to e^{-}{e}^{-}$

Being familiar with this "chain of thought" (Lagrangian --> Feynman diagrams --> Observable quantities) is very important because then you can appreciate directly from the Standard Model lagrangian what kind of physical phenomena to expect.

I will not forbid you to take this course if you are not familiar with the above but you must then make an additional effort to cover that. I will help you (contact me) and guide you through some of the expository material below that covers this subject.

Course purpose

Course literature

The course content consist of the material in the videos below and my lecture notes.  But there are lots of nice lecture notes available on the web that can be consulted as well. 

First of all, let me point you to a really nice initiative, called SCOAP3 where you find lots of high quality open access books on particle physics. Two books that contain additional material that can help you during the course are

1) The Standard Model and Beyond, by P. Langacker (Has a lot of preliminary material. The SM itself is only Ch. 8, and some parts a bit too technical for this course.)

2) An Introduction to Particle Physics and the Standard Model, by R. Mann. (Even more basic, unfortunately he does not use the Lagrangian much.)

In addition,here are some links to reviews published on the "arXiv" (the on line repository of preprints since 1991).

TASI 2013 lectures by H. E. Logan.

Lectures on the Theory of the Weak Interaction by M. E. Peskin.

From quantum mechanics to the standard model by B. Gripaios.

Standard Model: An Introduction by S.F. Novaes.

Changes since the last occasion:

None.

Learning objectives

- Acquiring the prerequisite theoretical tools for the construction of models of particle physics. 

- Understand the underlying principles and structure of the Standard Model of particle physics, with particular emphasis on the Higgs mechanism and the properties of the Higgs boson. 

- Work out basic predictions of the Standard Model and compare them with experimental data.  

Syllabus

Once you have the prerequisite of elementary QED (see prerequisites above), to construct the Standard Model you need to acquire three more theory tools. We start with a discussion of each one of them separately, in a simpler setting. They are I) Non abelian gauge invariance, II) Spontaneous symmetry breaking and III) Chirality. This will take up the first week of the course.The "real" course begins with the videos in  section IV) Construct the Standard Model.

I) Non abelian gauge invariance and some Lie algebra.

I made a bunch of videos to introduce the concept of gauge invariance, starting with a reminder of the abelian case. It's probably too much... Skip freely the material that is already familiar to you:

Plane electromagnetic wave 

Coupling the electromagnetic field to matter

From abelian to non-abelian symmetry. U(1), U(n), SU(n) groups and Lie algebras.

 Generators of the Lie algebra SU(n).

SU(2), SU(3), Pauli and Gell-Mann matrices.

More on representations of SU(3)

 Need for a covariant derivative

The covariant derivative of QCD

Gluon field strength.

The QCD Lagrangian and Feynman rules.

II) Spontaneous symmetry breaking. Global vs. Gauge symmetry. 

Here are some lectures reminding you the basics of symmetry breaking. Again, skip if you know this. Make sure you understand the difference between discrete/continuous, global/gauged, broken/unbroken symmetries. 

Introduction

Interlude: Comparing classical mech. quantum mech. and QFT.

Breaking of a global symmetry

Gauge U(1) symmetry.

Interlude: Meaning of a mass term for the gauge field.

Summary

III) Chiral spinors.

And now a few videos on chirality. I just focus on the parts that are relevant for the construction of the Standard Model lagrangian. You could look up additional material in one of the refs above (or your favorite QFT source).

 Representations of the Lorentz group

Spinor representations. Left and right handed components.

The Dirac Lagrangian and the coupling to gauge fields.

And now we are ready to: 

IV) Construct the Standard Model. 

Examination form