I read physics related major, but I feel confused after studying for a long time, I hereby reprint the relevant opinions of two great cattle, at least have a look at what physics is in the end, and read the blog “Academic corruption is inevitable in history” article is quite fruitful.
One: How to be a good theoretical physicist.
Gerard’s Hooft gives a list, Suggestions, explanations, and links to related resources on what to learn as a theoretical physicist.
The following link is the translation version of HMY (the translation version has the website address of the original version in foreign language) :
https://www.douban.com/group/topic/23010402/
 
2. Landau Barrier:
Content: differential equations, mathematical physics equations, tensor analysis and differential geometry
2. Mechanics
, except 27, 29, 30, 37, 51 (1988)
v.i.a.old, Mathematical methods of classical mechanics
3. Classical field theory
: Landau and Lifshits II, except for the following subsections: 50, 54-57, 59-61, 68, 70, 74, 77, 97, 98, 102, 106, 108, 109, 115-119 (1989)
4. Mathematics 2
exam content: complex function, special function (Bessel, ellipse, gamma, orthogonal polynomial), integral transform
5. Quantum mechanics
exam content: Landau-Lifshits III (1989) except the following subsections: 29, 49, 51, 57, 77, 80, 84, 85, 87, 88, 90, 101, 104, 105, 106-110, 114, 138, 152
6. Quantum electrodynamics
exam content: Landau-Lifshits IV (1980) except the following subsections: 9, 14-16, 31, 35, 38-41, 46-48, 51-52, 55, 57, 66-70, 82, 84-85, 87, 89-91, 95-97, 100-101, 106-109, 112, 115-144
7. Statistical physics I
exam content: Landau-Lifshits V divided by the following subsections: 22, 30, 50, 60, 68, 70, 72, 79, 80, 84, 95, 99, 100, 125-127, 134-141, 150-153, 155-160
8. Continuum mechanics
exam content: fluid mechanics, Landau-Lifshits VI (1986), divided by the following subsections: 1, 13, 14, 21, 23, 25-27, 28, 30-32, 34-48, 53-59, 63, 67-78, 80, 83, 86-88, 90, 91, 94-141
9. Continuum electrodynamics
examination contents: Landau-Lifshits VIII (1982) except the following subsections: 1-5, 9, 15, 16, 18, 25, 28, 34-35, 42-44, 56-57, 61-64, 69, 74, 79-81, 84, 91-112, 123, 126
10. Statistical physics II
exam content: landau-lifshits IX (1978), exam the following subsections: 1-5, 7-18, 22-27, 29, 36-40, 43-48, 50, 55-61, 63-65, 69
11.
physical kinetics: Landau-Lifshits X (1979), with the following section: 1-8, 11, 12, 14, 21, 22, 24, 27-30, 32-34, 41-44, 66-69, 75, 78-82, 86, 101.
while working in kharkiv, the 24-year-old Landau laid down the “minimum standard in theoretical physics”, a set of exams that came to be known as Landau’s “barrier”, for graduate students who wished to follow him. In accordance with the later standardized requirements, the “minimum standard” consists of a mathematics and eight theoretical physics interview. The last eight are theoretical mechanics, classical field theory including special and general relativity, statistical physics, non-relativistic quantum mechanics, continuum electrodynamics, physical dynamics, continuum fluid mechanics and elastic mechanics, and quantum field theory. The test focuses on problem-solving rather than abstract theoretical frameworks, and Mr. Landau once told young students that a well-prepared person should be able to pass the ‘minimum’ in three months or, if necessary, in a year. Many of Landau’s own students have been admitted on the “minimum” basis. In fact, the “minimum” is far from a barrier for Russian students interested in theoretical physics, who usually start at the beginning of their undergraduate studies. At first Landau presided over every exam, and later his professor-level assistants Shared most of the courses, but the first mathematics and the last quantum field theory were always landau himself. Landau kept a notebook in which he kept a personal record of the names and years of those who eventually passed. According to incomplete statistics, at least 18 of the 43 went on to become members or correspondents of the Academy of Sciences of the Soviet Union or the Republic of Korea, with one winning the Nobel Prize in physics. The only non-Soviet citizen on the list is L szlOTisza, a Hungarian who passed his exam in Kharkiv in 1935 and is still alive. He was a year older than Landau, moved to America in 1941 and taught at the Massachusetts Institute of Technology until he retired. A small number of people, after passing the “barrier”, are exhausted, exhausted and exhausted, and never appear again.