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Group Theory in Physics Wu-Ki Tung is a foundational graduate-level textbook that bridges abstract group representation theory with practical applications in classical and quantum mechanics. First published in 1985 by World Scientific
, it is celebrated for its pedagogical clarity, often presenting concepts from intuition to generalisation rather than just formal definitions. Physics Stack Exchange Core Content and Structure
The book is structured to guide students from basic definitions to advanced space-time symmetries. Key chapters include: Basic Group Theory and Representations
: Definitions, subgroups, and the general properties of irreducible vectors and operators. Continuous Groups
: In-depth coverage of one-dimensional continuous groups, the rotation groups , and their irreducible representations. Discrete and Symmetric Groups : Detailed treatment of the Symmetric Groups (Sn) using Young diagrams and partitions. Physics of Space-Time : Advanced topics such as the Lorentz and Poincaré groups , space inversion, and time reversal invariance. Essential Theorems : Comprehensive derivations of the Wigner-Eckart Theorem , Clebsch-Gordan coefficients, and Wigner's classification. World Scientific Publishing Distinguishing Features Physicist's Perspective
: Unlike purely mathematical texts, Tung focuses on group theory as a "springboard" for physical systems, keeping intermediate steps visible for self-study. Self-Contained
: Includes extensive appendices covering linear vector spaces, group algebra, and spinors to ensure students have the necessary mathematical background. Rigour with Pedagogy
: Important theorems are named rather than just numbered, and proofs are often deferred until after their physical significance is discussed. Availability and Resources
While the physical book is available for purchase at retailers like Amazon India
(approx. ₹1,500 for paperback), various digital formats exist for academic use: Group Theory in Physics - World Scientific Publishing
Group Theory in Physics by Wu-Ki Tung is a cornerstone textbook first published in 1985 by World Scientific. It is widely regarded as an essential bridge between introductory concepts and advanced theoretical physics, particularly in high-energy and particle physics. Core Pedagogical Approach
Unlike many mathematical texts that proceed from general definitions to specific cases, Tung’s approach is intuition-driven:
Intuition to Generalization: Concepts like isomorphisms are often introduced before homomorphisms because they are easier to visualize.
Clarity Over Rigor: The main text prioritizes the physical consequences and applications of theorems, while the more rigorous mathematical proofs are often deferred to detailed appendices to keep the book self-contained.
Detailed Intermediate Steps: The book is praised for keeping intermediate steps visible, making it highly suitable for self-study. Key Topics and Structure
The book spans 13 chapters and several technical appendices, covering both discrete and continuous groups: Group Theory in Physics 9971966565, 9971966573
Group Theory in Physics by Wu-Ki Tung is widely regarded by reviewers from Amazon and academic communities like Physics StackExchange as a definitive bridge between introductory and advanced mathematical physics. Core Overview
The book serves as a pedagogical introduction to group representation theory, specifically focusing on its role as the mathematical framework for symmetry in classical and quantum systems. It is primarily aimed at advanced undergraduates and beginning graduate students. Key Strengths
Logical Flow: Reviewers note that Tung often reverses the standard order of topics—moving from intuition to generalization (e.g., teaching isomorphisms before homomorphisms)—to aid comprehension.
Fills "The Gap": It explicitly covers rigorous material that introductory books often skip but advanced texts assume the reader already knows, such as the Wigner-Eckart theorem, Young tableaux, and Wigner’s classification.
Step-by-Step Clarity: Unlike many dense math texts, Tung often includes intermediate calculation steps, making it highly suitable for self-study.
Authoritative Endorsement: The book is famously cited as a reference by Nobel Laureate Steven Weinberg in his foundational Quantum Theory of Fields. Critical Considerations
Mathematical Density: While written for physicists, the notation can be dense and formal. Some readers find it leans more towards pure math with fewer explicit physical applications in the middle chapters.
Production Quality: Several user reviews from Amazon UK mention that the physical print quality (paper and graphical layout) is not as high as modern textbooks, though the content remains top-tier. Who is it for? Group Theory in Physics : Tung, Wu-Ki - Amazon.de
Title: Looking for / Sharing: Group Theory in Physics – Wu-Ki Tung (PDF)
Post:
Hi everyone,
I'm currently studying the applications of group theory in quantum mechanics and particle physics, and one text that keeps coming up as a classic is "Group Theory in Physics" by Wu-Ki Tung (World Scientific, 1985).
Unlike many pure math treatments, Tung's book is highly regarded for its physics-first approach — covering finite groups, Lie groups, and their representations with clear connections to angular momentum, particle classification, and scattering theory. It sits nicely between the rigor of Hamermesh and the more applied style of Georgi.
If anyone has a PDF copy they're willing to share, I'd greatly appreciate it. Alternatively, if you've worked through this book, I'd love to hear:
Happy to exchange notes or problem solutions with others currently going through the text.
Thanks in advance!
Optional hashtags (for social media or forums like Reddit, Twitter, or Physics Forums):
#GroupTheory #WuKiTung #MathematicalPhysics #QuantumMechanics #PDFRequest
Unlike many competing texts that focus solely on SU(N), Tung dives deeply into the Lorentz group (SO(3,1)) and its covering group SL(2,C). He explains two-component spinors and four-component Dirac spinors from a group-theoretic origin, showing exactly how the Dirac equation emerges from the representation theory of the Lorentz group.
One compelling lesson of Tung’s exposition is that group theory is more than a toolbox for solving particular problems. It’s a language for expressing constraints, classifications, and possibilities. When you see an unfamiliar physical system now, the first act of the theorist is often linguistic: Which symmetry group governs it? What representations are available? What symmetry breakings are permitted? In this framing, the PDF is a lexicon and grammar in one volume—practical for calculation, but richer as a mode of thought.
This perspective has practical consequences. Consider the modern frontiers: topological phases, quantum information protocols, and symmetry-protected phenomena. Each draws on group-theoretic ideas, but the real advance comes when symmetry is used imaginatively—not only to classify, but to conjecture new mechanisms and constraints. Tung’s work cultivates that imaginative use by tying formal representation theory directly to the canonical problems of physics.
If you are searching for a PDF of Tung, you may be debating which book to commit to. Here is a quick comparison:
| Textbook | Focus | Difficulty | Best For | | :--- | :--- | :--- | :--- | | Wu-ki Tung | Physics applications (QFT, particle, relativistic QM) | Intermediate-Advanced | The first serious physics-oriented course. | | Howard Georgi ("Lie Algebras in Particle Physics") | SU(N), grand unification, instantons | Advanced | QFT specialists; assumes more prior knowledge. | | Robert Gilmore ("Lie Groups, Physics, and Geometry") | Broad, geometric | Advanced | Those wanting mathematical rigor with physics. | | Morton Hamermesh ("Group Theory and Its Application to Physical Problems") | Comprehensive, classic | Advanced / Dense | Reference for atomic/molecular spectra. | | Pierre Ramond ("Group Theory: A Physicist's Survey") | Modern, elegant | Advanced | Theoretical mathematicians doing physics. |
Tung’s advantage is his balance: while Georgi dives immediately into SU(N) algebra, Tung first builds intuition with SO(3) and the Lorentz group. While Hamermesh is exhaustive but dry, Tung is engaging and pedagogical.
Definition (Lie algebra): A Lie algebra g is a vector space with bilinear bracket [ , ] satisfying antisymmetry and Jacobi identity. For generators Ta of a Lie group G, [Ta, Tb] = i fabc Tc.
SU(2) representation: Irreps labeled by spin j (dimension 2j+1). Basis |j,m>, m = −j,...,+j. Ladder operators J± = Jx ± iJy with J±|j,m> = sqrt((j∓m)(j±m+1)) |j,m±1>.
Clebsch–Gordan decomposition (example): For two spin-1/2: 1/2 ⊗ 1/2 = 1 ⊕ 0 (triplet + singlet). Triplet symmetric, singlet antisymmetric.
Young tableaux (SU(3)): Boxes arranged in rows; irreps correspond to (p,q) Dynkin labels where p = # boxes in first row minus second, q = # boxes in second row minus third; dimension formula: dim(p,q) = (1/2)(p+1)(q+1)(p+q+2).
Wigner–Eckart theorem (statement): Matrix elements of tensor operator T^(k)_q between states |j,m> factor as <j' m'| T^(k)_q | j m> = <j' || T^(k) || j> × (j k j'; m q −m') (proportional to a CG coefficient).
Modern physics prizes rapid iteration: compute, publish, move on. But foundational progress often requires something else: sustained, careful reading of deep texts until new connections emerge. My challenge to the community—students, postdocs, and senior researchers alike—is to treat Tung’s Group Theory in Physics as an exercise in slow scholarship. Read it with a pencil. Re-derive results in modern notation. Ask how classic theorems might illuminate current puzzles: anomalies, dualities, or the algebraic underpinnings of quantum computation.
Doing so has pragmatic payoffs. A researcher fluent in group-theoretic technique can spot constraints in model-building earlier, cut through algebraic clutter faster, and propose symmetry-based experiments with confidence. Beyond that, cultivating the habit of deep reading guards against a superficial engagement with theory—a problem as real as any computational bottleneck.
Tung’s approach is not bite-sized. He patiently builds representation theory from first principles, then carries it through applications to angular momentum, Lie algebras, and the symmetry groups that underpin quantum mechanics and field theory. Each chapter functions like a finely tuned argument: definitions, theorems, worked examples, and then a return to physical meaning. In an era where ideas are often consumed in twenty-minute reads, a full-length PDF of Tung’s work demands a different attention—slow, cumulative, and ultimately more generative.
For the practicing physicist or the curious graduate student, this is a feature, not a bug. Real insight in theoretical physics often emerges where formal structure and physical intuition overlap. Tung’s book trains readers to live in that overlap, to move fluently between algebraic manipulations and statements about observables and conserved quantities. That sort of fluency is precisely what short tutorials and blog posts rarely provide.
Assuming you obtain the book (legally, we hope), here is a roadmap to mastering its contents:
Month 1: Work through Chapters 1–4 (Finite groups and basic representation theory). Do all the problems involving S_3 and S_4. Master the character table method.
Month 2: Chapters 5–7 (Lie algebras, SU(2), SU(3)). Derive the angular momentum algebra from scratch. Draw the SU(3) root diagram by hand. Compute the quark model wavefunctions.
Month 3: Chapters 8–9 (Lorentz group). This is the hardest part. Spend two weeks just understanding the difference between SO(3,1) and SL(2,C). Do the spinor algebra until it becomes intuitive.
Month 4: Chapters 10–12 (Gauge theories). Here, the book connects to quantum field theory. If you are not yet studying QFT, you can pause. But for particle physicists, this is the payoff.
Pro tip: Watch YouTube lectures on group theory for physics alongside reading Tung. Channels like "Tobias Osborne", "XylyXylyX", or "Institute for Advanced Study" video series can demystify the abstract passages.
If you manage to get your hands on a digital copy of this text, here is the roadmap of the most valuable chapters: