Peskin勘误

Corrections to

An Introduction to Quantum Field

Theory

by

Michael E. Peskin

and

Daniel V. Schroeder

(

Westview Press

, 1995)

We extend our thanks to the many readers who have reported errors in our

book. We hope that the corrections will bring our book closer to that level of

technical perfection that students long for but authors find so elusive.

Errors that were report before March 2001 are corrected in the summer 2001

printing and in more recent printings of our textbook. These errors are

corrected in any printing of the book with `Westview' on the spine. If you

own such a book, please skip directly to the

list of errors reported since

March 2001

.

Recently, Michael Peskin taught the Quantum Field Theory course at

Stanford and added some material that is not included in the textbook. We

provide the new lectures here in case in the hope that they might be useful:

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Renormalization: a 2-loop example

(an improvement of Section

10.5).

Lattice models of scalar fields and gauge fields

(supplement to

Chapters 13 and 16).

Grand unification

(supplement to Chapter 20).

Magnetic monopoles in unified gauge theories

(supplement to

Chapter 20).

Instantons and nonperturbative QCD

(supplement to Chapter 19; but

please first read the lecture on magnetic monopoles).

In addition, Michael Peskin has put on the arXiv some pedagogical lecture

notes on calculational methods for QCD at colliders. We hope that fans of

our textbook might find these useful:

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Simplifying Multi-Jet Computation, arXiv:1101.2414

(supplement to

Chapter 17).

Errors that were reported before August 1997 are corrected in the fifth

printing (December 1997) and in more recent printings of our textbook.

Those errors are corrected in any printing of the book with `Perseus' on the

spine. If you own such a book, however, you might wish to look at the

list of

errors reported from 1997 to 2001

. Two lengthy notes (to p. 46 and p. 79)

were not included in the more recent corrected printings, and these are

transferred to the list on this page.

Roni Harnik recently presented to us

some evidence that our book is in good

taste

.

Marilena Loverde and Laura Newburgh provided us with a photo-essay on

the ATLAS experiment (created for the 2012 Washington Post Peeps

competition) that demonstrates that our textbook is essential equipment at

the LHC:

overview of ATLAS

;

essential textbooks

.

The list of errors in the original edition of our book is quite long. Only a few

of these errors have important consequences. However, there are many

minor errors in individual derivations. We have therefore reorganized the

list into a catalogue of

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errors grouped by level of importance

Owners of the first four printings might wish to mark only the errors in the

highest category and keep the rest of the list for reference. For those who

would like a complete list of the errors, we have also prepared catalogues of

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errors given sequentially by page number

;

errors grouped according to the dates when the corrections were

reported

.

We would be most grateful to hear of any further errors that are not listed on

these pages. Please send them by e-mail to

mpeskin@

.

Errors reported since March 2001, updated March 2012:

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Notations and Conventions:

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Chapter 2:

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p. 18: [The following correction has been here for some time, but it

was posted in error and should be removed. We apologize. Eq. (2.15)

is consistent given the definition of Delta in (2.9). The incorrect

correction read: In eq. (2.15), the factor of

side of each equation should be omitted. (Thanks to R. Kallosh for

straighting us out.)]

p. 28: Two lines under eq. (2.53), the phrase

separately Lorentz invariant

separately invariant under continuous Lorentz transformations

(Thanks to T. Wettig.)

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Chapter 3:

p. 42: In the unnumbered equation at the bottom of the page, please

note that the notation

y^nu psi(y), evaluated at y = Lambda^{-1}x

psi(Lambda^{-1}x) = (Lambda^{-1})^nu_mu del_nu

psi(Lambda^{-1}x). This is the origin of the factor

(Lambda^{-1})^nu_mu on the right-hand side of the first line.

(Thanks to J. Fredsted).

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p. 46: On this page, the spinors u(p) are represented using square

roots of matrices: sqrt() and sqrt(ar). It is useful to

note that these objects can be rewritten without square roots of

matrices as: sqrt() = ( + m)/sqrt(2(p^0 + m)) , and

similarly for sigmabar, for a 4-vector p such that p^2 = m^2. (Thanks

to Prof. A. Sirlin!)

p. 61: In the eighth line on the page

p. 61: In the second line below the first displayed equation, the

indices r on a^dagger operators should be changed to r'. In the second

displayed equation, u^dagger and xi^dagger should have the index r

and u and xi should have the index s. The final result of the

calculation is unchanged. (Thanks to R. Lebed.)

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Chapter 4:

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p. 79: We are informed that the gauge condition

which in every modern textbook is called the `Lorentz condition',

should actually be the `Lorenz condition'. Ludwig Valentin Lorenz,

the inventor of the retarded potential, actually wrote down this

condition in 1867, when Hendrik Antoon Lorentz was 14 years old. It

is another example of the Matthew effect at work. See E. T.

Whittaker, A History of the Theories of Aether and Electricity, vol. 1,

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p. 269 and J. Van Bladel, IEEE Antennas and Propagation Magazine,

vol. 33, p. 69 (1991). (Thanks to J. Bielawski.)

p. 124: In the setence just below the figure,

(Thanks to K. Matawari.)

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Chapter 5:

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p. 156: There is some confusion in the paragraph just below eq. (5.70).

In the crossing procedure described, the initial electron momentum p

and the final muon momentum k remain unchanged, while the initial

positron momentum p' is continued to the momentum of a final-state

electron and the final anti-muon momentum k' is continued to the

momentum of an initial state muon. Since p and k are unchanged,

(p-k)^2 is unchanged. We wrote in the text that u is unchanged, but

this is not quite right. In e-e+ -> mu-mu+, we would naturally call

(p-k)^2 = t, but in e-mu- -> e-mu-, we would naturally call (p-k)^2 =

u. So, the rearrangement described in the text as s <-> t with u

unchanged is described better as s->t t->u u->s. However eq. (5.71) is

symmetric under interchange of s and u, so either crossing process

gives the right answer. (Thanks to C. Schubert.)

p. 169: In the equation in Problem 5.1, the right-hand side should be

multiplied by Z^2 to be consistent with Problem 4.4, part (c). (Thanks

to B. Souto.)

p. 171: In the fourth line of Problem 5.3, part (d),

replaced by

p. 172: In Problem 5.4, part (c), there are two issues. First, in the

formula for |B(k)> we should have been more explicit and written:

the creation and annihilation operators as tw-component objects: a_k

= (a_1, a_2), b_k = (b_2, b_1). More importantly, the last lines of part

(c) should read:

= 1/sqrt{2} and all other components zero. (Thanks to J. Wang.)

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Chapter 6:

p. 188: At the bottom of the page, we say,

differs by 40% from the Dirac value.

proton is 5.58, almost a factor of 3 away from Dirac. Nevertheless, eq.

(6.33) still applies, as it does for any spin-1/2 particle. The large value

of g is easily understood when the proton is modeled as a bound state

of three quarks, each of which has a g-factor close to 2. (Thanks to R.

Gerasimov.)