Announcements for Physics 752 (Prof. Agashe)  Spring 2017
(0). For all homeworks,
please read carefully the statements of problems, especially since notes/hints
have been given in many places.
(1). HW 7 (due April 12, Wednesday, during lecture) on nonabelian gauge
symmetries at quantum level and HW 8 (due April 26) on SM theory are assigned here.
(2). HW 9 and 10 (last ones for this
course) on SM phenomenology also
have been assigned here
and are due May 3 and 10 (respectively).
(3). Solutions to HW 17 are posted here.
(4). Term paper presentations (slides preferred) will
be 10 am. to 3 pm. (with 1 hour break for lunch) on May 15 (Monday) and May 16 (Tuesday): 4 on each day.
Writeup (at least 10 pages long) will be
due Wednesday, May 17 by 5 pm.
(5). Some
notes (two on QCD and one on Z decay width)
are posted here.
(6). Please try to print and fill out the feedback survey here
(2 pages) and return it to me (without
your name on it) during lecture: this is just to help me improve teaching:
thank you very much in advance for doing this!
(7). Plan for lectures starting March 27: we
will use the 3 QFT topics that we studied so far to first construct the standard model and then study its phenomenology (based on chapter 15 of LP, supplemented by other
references that I will give as we go).
The
topic that we finished just before
was nonabelian gauge theories
[needed for describing both strong
and weak (nuclear) forces]:

first, we considered global
symmetries (sec. 13.2 of LP), including their spontaneous breaking (sec.
13.4.3)

then we gauged these symmetries and
discussed the classical theory (sec. 14.1 to 14.4 of LP): their spontaneous
symmetry breaking was studied based on Peskin,
Schroeder (PS)Ős pages 692694

finally, quantization of nonabelian gauge theories was studied (sec. 14.5 of
LP)
The
even earlier topic of Higgs
mechanism is needed for describing weak (nuclear) force within the SM: the outline here
was

first, we discussed spontaneous breaking of a global symmetry (section 13.4 of LP).

above model was be shown to have massless
scalar particle [called NambuGoldstone boson (NGB)]:
we also discussed nature of its Interactions (section 13.5 of LP). Existence of
such NGBŐs in general (i.e.,
GoldstoneŐs theorem) was proven following PS pages 351352

finally, we gauged the above global
symmetry section 13.6 of LP) to find that the corresponding gauge boson
acquires mass (and NambuGoldstone boson "goes away") and theory
remains renormalizable: for this purpose
it was crucial to argue that there is no dependence on gaugefixing parameter
in the total amplitude for a process (see PS pages 734739).
Finally,
the 1^{st} QFT topic was renormalizability of
QED, based on chapter 12 of LP.