2025-12-12. Main Book: Version 1.01, some minor typos. Answer Book: Version A.1.01, lots of typos and corrections on Chapter 1. 

2025-12-12. Main Book: Version 1.02, minor typos. Answer book: Version A.1.02, many typos and corrections on Chapter 2. 

2025-12-26. Main Book: Version 1.03, a few minor typos and language corrections. Answer Book: Version A.1.03, many  typos and corrections on Chapter 3, and equation numbers in the exercises statements matched with the Book. 

2026-01-02. Main Book: Version 1.04; removed former (wrong) Proposition 6.3.10, plus minor correction in a few exercise statements. Answer Book: Version A.1.04; many typos and corrections in Chapters 4, 5, and 6; Exercise 9.1.6 had been using the wrong Proposition, so the argument has been corrected. 

2026-01-13. Main Book: Version 1.05; typo on introduction to weak topologies and minor mistake corrected in the proof of Lemma 12.3.16; a couple of other minor typos.  Answer Book: Version A.1.05; typos and corrections in Chapters 7 and 8. Corrected the proof of Exercise 7.4.6. Changed the statements of Exercises 7.4.7 and 8.3.4. 

2026-01-25. Main Book: Version 1.06; minor changes in the proof of Proposition 9.2.21 to avoid early mention of characters; minor change to Exercise 9.2.16; minor change in Example 9.5.10; minor error in the statement of Exercise 9.6.16; typo in the title of subsection 9.8.2; "selfadjoint" missing in the statement of Exercise 10.2.3; minor change to the statement of Exercise 10.6.25; changed the statement of Exercise 11.5.5; correction in the statement of Exercise 11.5.7; typo in the statement of Proposition 11.6.3; minor change in the first paragraph of Chapter 12; corrected Remark 12.1.14; minor change in the statement of Exercise 12.7.3; clarified statement of Exercise 12.7.10; improved statement of Exercise 13.2.13 and included mention of this in the proof of Theorem 13.2.15; added Exercise 12.1.23; removed Exercise 13.2.27 (duplicate of 13.2.21); moved Exercise 13.4.2 to Section 13.1 where it belongs; added local table of contents to section 13.4; added mention of sot in Exercise 13.4.13; minor change of notation in Exercise 13.4.19; corrected Exercise 13.4.24.   Answer Book: Version A.1.06; solved equation numbering issues; many typos and corrections in Chapters 9-13; changed the answer to Exercises 13.2.32 and 13.4.23. 

2026-02-01. Main Book: Version 1.07; mistake in the statement of Exercise 10.5.16; included new Exercise 12.1.24; changed the statement of Exercise 14.2.8; slightly changed the statement of Corollary 14.2.18; clarified the statement of Exercise 14.2.19; exchanged Exercises 14.3.2 and 14.3.4, as the former needs the latter; clarified the statement of Exercise 14.3.3; clarified statement of Exercise 14.5.2; made Lemma 14.5.22 into a Proposition and clarified the statement; added Exercise 14.5.13; added a new Exercise B.3.1 to correct Remark B.3.2 (it was circular) and to help with what now is Exercise B.3.2; clarified the statement of Exercise F.0.11; corrected Exercise F.0.13. Answer Book: Version A.1.07; many typos and corrections in Chapter 14 and the Appendices; changed the answer of Exercises 14.2.8 and F.0.12.