Announcements for Physics 752 (Prof. Agashe) - Spring 2011


(1). Schedule for last two lectures (Friday, May 6 and Monday, May 9): 11 am.-12.15 pm.

       in Room 4102.


       After discussing CP violation from CKM matrix, I will briefly discuss QCD, roughly  

       following sections 17.2-17.4 of Peskin and Schroder. I already went over the

       historical overview of QCD in their section 17.1 in lecture.


       Some notes for QCD discussion have been posted here.


       For discussion of CKM matrix, sections 11.3 and 12.2 of Cheng and Li and sections

       II-4, IX-1 and XIV-5 (specifically page 407 onwards) of Donoghue, Golowich and

       Hosltein might be useful.


(2)  All HW’s are now assigned here (2 more problems have been added in HW 6, relative

      to 1st  version and some comments have been added in HW 7, but no extra problems)


            Deadline for all HW’s and term paper is May 16.


(3). Term paper


      The length of term paper will obviously depend on the topic (+ size of margins etc.!),

       but I am expecting a minimum of (roughly) 10 pages (single spaced).


       Here is the presentation schedule in Room 4102 (each slot includes time for



             May 12 (Thursday)

                 11-noon: GUTs (Ranchu Mathew)/anomalies (Simon Riquelme)

                 1-4: SUSY (3 talks by Anton De La Fuente, Yong Zhao and Chris Verhaaren –

                                    order to be decided by presenters)

May 13 (Friday)

                 10-noon: extra dimensions (2 talks by Andy Latief and Wrick Sengupta – order to

                                                             be decided by presenters)

                 3-4: anomalies/GUT




(Some) Earlier announcements:



(4). Notes on path/functional integral formalism have been posted here.


(5). Outline for last several weeks: discussion of theory of Standard Model, (to begin with) 

      based (roughly) on Chapter 15 of Lahiri and Pal (for electroweak sector).


(6). Term paper (instead of final exam)


(i) Topics are here.


(7). HW 3 (due Monday, March 14) and 4 (due Monday, March 28) have been assigned here:


       (i)  HW 3.4 has been corrected (there is a remnant symmetry…)


       (ii) Hint for HW 3.4 (using radial representation) has been added.


       (iii) HW 4.5.1 (deriving Feynman rules for gauge boson quartic vertex) has been added.

       (iv). HW
4.5.2: the Feynman rules for gauge boson self-interactions are in Fig. 14.1 (and    

              those for ghosts are in Eqs. 14.43 and 14.44 as indicated in earlier version).


(8). Outline for next couple of weeks:


      In week 6, I will start discussion of (global) non-abelian symmetries, including their  

      spontaneous breaking (roughly along the lines of sections13.1, 13.2 and 13.4.3 of Lahiri

      and Pal).

      Then, I will discuss
gauging (at classical level) these symmetries (roughly along the 

       lines of sections 14.1 to 14.4 of Lahiri and Pal).

       Finally, I will discuss
path integral quantization (which is sort of a "must" for non-abelian
       gauge theories) - I will send you notes/references on this topic later.



(9). HW2 is here:


(i) Deadline is extended to Friday, March 4.


      (ii) Corrected/revised HW 2.6 is now posted.


      (iii) HW 2.4 on zeta-eta scattering in radial representation: according to one of the       

           authors (Pal), the amplitudes are exactly same in the 2 representations.

           As for my question about whether the zeta and eta fields in the two representations   

           not being exactly equal implies the equality of amplitudes is valid only in some limit   

           (e.g. momenta << v), the authors' answer was (which I still need to digest so that I  

           simply quote it here verbatim) "Two fields need not be exactly equal in order to give the

           same S-matrix elements.  There is a theorem by Haag to that effect.  See, e.g.,
           "Dynamics of the standard model" by Donoghue, Golowich and Holstein, page 101."



(10). Homework 1 (due February 14) has been assigned here.


       Please note the revision - the problem on relating Z_1 and Z_2 in both dimensional and

       cut-off regularizations has been added.


(11). Outline of topics:


(i) Week 3 onwards: after finishing renormalization, I will discuss spontaneous symmetry 

     breaking and Higgs mechanism, roughly based on sections 13.4, 13.5 and 13.6 of 

     Lahiri and Pal.

     (I'll discuss the topic of general symmetry groups, roughly based on sections 13.1 and  

     13.2 of Lahiri and Pal later.)


     (ii) Weeks 1-3: I will discuss renormalization based on chapter 12 of Lahiri and Pal   

          this/next week (chapter 2 of Cheng and Li is also a good read for this topic, where the

          counterterm renormalization scheme is introduced in section 2.2).

         In particular,

         (a) I will
skip sections 12.9.1 (Lamb shift) and 12.9.3 (cancellation of IR divergence)

               since these are not so relevant for our goals.

        (b) In class, I will go through calculation of vacuum polarization diagram using

             dimensional regularization and adding of counterterms for it...

             However, I will leave a similar detailed discussion of fermion self-energy diagram for   

             HW1 (see sections 12.6.2 and 12.7.2 for this discussion using a different 

             regularization scheme, namely, Pauli-Villars, with similar end-result).