Endnotes
Note 3: When amplitude affects frequency
- Quote: In a sense, frequency and amplitude keep out of each other’s way. This carries over to our perceptions: frequency determines pitch without affecting loudness, while amplitude determines loudness without affecting pitch.
- Endnote: These statements are true as long as the amplitude is small enough. When the amplitude is very large, the independence of frequency and amplitude may fail. For instance, overblowing a flute or a recorder pushes the frequency (and the pitch) up slightly.
- Discussion
Note 6: String theory and string fields
- Quote: The universe’s fields, from the electric and magnetic fields to the Higgs field, have been extensively studied in experiments, and we know a great deal about them. String theory, sitting at the next level of potential knowledge, represents an attempt to explain where the fields come from.
- Endnote: According to string theory, many types of elementary particles may actually be one type of string vibrating in different ways, and the universe’s many fields may be different aspects of a single string field.
- Discussion
