From right to left: "A Shorter Course of Theoretical Physics (Japanese) [=Краткий курс теоретической физики. В двух томах (Russian)]" Volume 1 and 2 (Mechanics and Electrodynamics / Quantum Mechanics respectively), Mechanics (Volume 1, Japanese), The Classical Theory of Fields (Volume 2, Japanese), Quantum Mechanics: Non-Relativistic Theory (Volume 3, English), Quantum Mechanics: Non-Relativistic Theory 1/2 & 2/2 (Volume 3, Japanese), Quantum Electrodynamics 1/2 & 2/2 (Volume 4, Japanese), Quantum Electrodynamics (Volume 4, Russian), Statistical Physics, Part1, 1/2 & 2/2 (Volume 5, Japanese), Fluid Mechanics 1/2 & 2/2 (Volume 6, Japanese), Theory of Elasticity (Volume 7, Japanese), Electrodynamics of Continuous Media 1/2 & 2/2 (Volume 8, Japanese), Statistical Physics, Part 2: Theory of the Condensed State (Volume 9, Russian), Physical Kinetics (Volume 10, Russian). |

Although there is no "

*" (and no "***volume 9, Statistical Physics Part 2***" & no "***volume 4, Quantum Electrodynamics, Part 2***) on the web, the well-known Course of Theoretical Physics was a mandatory***volume 10, Physical Kinetics**"*(before the entrance exam of graduate schools of those days) series of textbooks*which is now available for free here (U.S. archives) and here (an old version of the Russian original). However, editions of English translation are not up-to-date and such editions do not have a good TeX typesetting; there are something like the followings: \begin{align*} <M \mid L_{+} \mid M-1 >=<M-1\mid L_{-}\mid M>\\ =\sqrt{ }[(L+M)(L-M+1)]. (27.12) \end{align*} [from the Quantum Mechanics [Volume 3, English ed.]] The Japanese edition is TeXnically correct.__written by students of L.D.Landau (Nobel Laureate in Physics [the prize for the theory of liquid helium's superfluidity], 1962 and his Nobel speech)__,
\begin{align*} <M \mid L_{+} \mid M-1 >=<M-1\mid L_{-}\mid M>\\
=\sqrt{(L+M)(L-M+1)} (27.12)
\end{align*}(a period or a comma should be inserted.) Likewise, the semi-classical approximation is

\begin{align*}
f_{12} \sim \exp \left\{ -\frac{1}{\hbar} \text{im} \Big[ \int^{x_0} \sqrt{ } [2m (E_2-U)] dx\\
- \int^{x_0} \sqrt{ } [2m (E_1 - U)] dx \Big] \right\} (51.6) \end{align*} in the English edition. It should be
\begin{align*}
f_{12} \sim \exp \Bigl( -\frac{1}{\hbar} \text{Im} \Big[ \int^{x_0} \sqrt{2m (E_2-U)} dx\\
- \int^{x_0} \sqrt{2m (E_1 - U)} dx \Big] \Bigl) (51.6) \end{align*}
as is written in the Japanese edition. (Russian originals of volumes 4, 9, 10 seem OK for the square roots including fractions.)

**volume 4 [year 2006, 4th ed.] "Квантовая электродинамика"=Q**

*uantum Electrodynamics [2nd ed.] (*

*, 9 [year 2004, 4th ed.] "Статистическая физика. Часть 2. Теория конденсированного состояния"=Statistical Physics Part 2: Condensed Matter Theory (or Statistical Physics, Part 2: Theory of the Condensed State), 10 [year 2007, 2nd ed.] "***or***Relativistic Quantum Theory [1st ed.]*)*) of the original Russian to my bookshelf -- since the new / re-print editions of Japanese translation are no longer available for a long time. This situation is the same for the undergraduate students at the University of Tokyo of 17 years ago, and we had to share the old sombre fragile archives of the [physics / liberal arts / city] library (a stack room for books including Russian), or physics-oriented students can purchase some of the easier-to-obtain editions from secondhand booksellers at the Kanda (Jimbo-cho -- where I went and buy the three books above) city in Tokyo. [The exceptionally well-sold editions of volume 1, 2, 3 1/2 from the Tokyo-Tosho press and the volume 5 1/2, 5 2/2 of*

**Физическая кинетика"=Physical Kinetics***from the Iwanami press are not out-of-print].*

**Statistical Physics, Part 1**
I was lucky in my undergraduate days that I could obtain (by a reasonable price) the volume 6 1/2 & 2/2 (=3rd ed. of original Russian) of

*and the volume 7 (=4th ed. of original Russian) of***Fluid Mechanics***in the Japanese translation from the CO-OP (student union) of the University of Tokyo in my undergraduate days (1998 April-2002 March). I did not buy the volume 9 of***Theory of Elasticity***from the Iwanami press in my undergraduate days.***Statistical Physics, Part 2**
More nostalgically speaking, I was reading the volume 1 of Mechanics and the volume 5 of Statistical Physics when I was a freshman of the University of Tokyo of the year 1998-1999. This was only the prologue of my professional work of theoretical & mathematical physics in addition to pure algebraic (& arithmetic) geometry and algebraic analysis. While I was thinking about becoming a professional mathematician, it turned out my pursuit of learning both modern math [including number theory and arithmetic geometry] and theoretical physics [including elementary particle theory] was impossible at the governance system of the University of Tokyo at those days -- there was no Kavli-IPMU institute, there was no double major Ph.D., and there was a strong bashing / adversity against pure science and pure math. There was no communication between the physics department of UT's Hongo campus and the math department of UT's Komaba campus.

In my undergraduate days, some of the applied physicists and literature / social science students accused my particular interest was "inside the philosophy" or "religion-like" -- which was (as if) the same words "This is

*not mathematics*; this is*theology*." [1890s] as the critics (of Paul Gordon) to Hilbert when Hilbert tried to defend the set theory**of Cantor at the beginning of the 20th century (from Kronecker -- whose argument with Cantor was reconciled at the very end of Kronecker's life). The initial goal to establish the set theory was not the topology or the real / complex number, but the uniqueness of the Fourier transform / inverse transform as the trigonometric series. This concrete goal was not achieved as the unification of number theory and physical mathematics, but its idea (or, Cantor's dream) is still alive in another form of the category theory of homotopy algebras in arithmetic geometry and higher topos theory (and the elementary topos theory [not always Grothendieck topos] of sheaves in logic and the type theory).***[its ultimate initial plan of so-called Hilbert's program was not achieved -- but I don't write about this misleading popular science in this post. I just draw your attention to the fact that the Hilbert program was something that the earlier-20th-century mathematical physicists (including von Neumann) were sharing but its historical meaning has no consensus between arithmetic geometers and mathematical physicists.]*
At the days of Cantor, there was no delta function, no Bourbaki, no Grothendieck, no Landau-Lifshitz, no CERN LHC for Higgs bosons, and no superstring theory / M-theory. However, the pure mind of Cantor is still alive everywhere in the garden of modern mathematics.