Pinyin has tones, one to four tones softly. I wonder if the pitches of these tones are the same in music. If not, how to express it by notation? thank you

No, because in music, pinyin has different pitches. Light tones correspond to bass, one tone corresponds to alto, two tones correspond to treble, three tones correspond to ultra-treble, and four tones correspond to ultra-treble. If represented by symbols, it can be represented in the following ways:

Whisper:?

1:?

Two:?

Three times:

Four tones:?