In the elevator, Zhao Xingsheng's face was black, and his three graduate students were all covering their mouths and snickering.

After all, on the way here, Zhao Xingsheng had already boasted to them that Gu Xiaobai had exploded all the way, as if he was the number one fan.

But when they really met, Gu Xiaobai didn't remember his face.

You say it's not annoying.

At this moment, in the elevator, Gu Xiaobai was looking at him with his head down.

In such a small space, Zhao Xingsheng found out that Gu Xiaobai was really tall, Zhao Xingsheng's height was close to one meter eight, which was considered tall at his age, and Gu Xiaobai was half a head taller than him.

Although he is still thin and tall like a teenager, he looks a little thin, but it also makes Zhao Xingsheng sigh with emotion, the nutrition of today's children is really good.

Zhao Xingsheng was a little hairy by Gu Xiaobai, and said in a rough voice: "What do you think I'm doing?"

"Add your face to the faces of important people and write it down. Gu Xiaobai said, still muttering in his mouth: "Professor Zhao, Zhao Xingsheng, crayfish, old meerkat......"

"What did you say?" Zhao Xingsheng heard his name, and the last two were a little puzzled, and they always felt uncomfortable.

"Associative memory. Gu Xiaobai pointed to his brain.

Zhao Xingsheng is a little injured again, I look so mediocre, I still need associative memory to remember.

It's heartbreaking.

Skillfully opening the door of the laboratory, Gu Xiaobai began to prepare consumables for Zhao Xingsheng again, filled in the list, and turned on the equipment...... Apparently he's been here many times.

Zhao Xingsheng also nodded with emotion.

The competition is fierce, not only for the students, but also for the teachers.

Especially for young professors like them, it is not easy to gain a firm foothold in the school, and it is absolutely impossible to grab other big bulls if they want to grab resources, but with a student of the Campus Hundred Sons Program, they have the capital to grab resources and let the school tilt resources.

On the phone, he had an in-depth understanding of Gu Xiaobai with the old Wang next door, Gu Xiaobai, who has just been a freshman, is extremely expected to be shortlisted this year, even if he can't be shortlisted this year, in Professor Wang's own words, that is......

"If I can't get into the circle again next year, I will eat guitar live in front of the principal!" said Lao Wang, who is the guitarist of Professor Zhao's band.

With such an excellent student, the teachers are willing to give him the green light wherever he goes. The young doctoral and master's supervisors, who ordinary students often have deep contact with in their senior year, have now begun to carefully guide Gu Xiaobai.

Seeing Zhao Xingsheng coming, Gu Xiaobai hesitated for a moment and asked, "Teacher, are you busy?"

"It's okay, waiting for the results. ”

"Then can I ask you a question?" asked Gu Xiaobai.

"Say it. Zhao Xingsheng pulled a chair and sat down in front of Gu Xiaobai, as relieved as the old father who saw his son finally marry a wife, and almost burst into tears.

The mentality of the fans exploded instantly.

Xiaobai asked me a question!

Gu Xiaobai looked at Zhao Xingsheng seriously and asked:

"Teacher, may I ask about the music...... What is it?"

What is music?

Zhao Xingsheng didn't expect Gu Xiaobai to ask such a question.

Science students, if they want to figure out what 2+2 is equal to, they never start with 2+2 directly, they have to figure out 1+1 first.

"If you want to explain the problem of music to you science students, it's more difficult to ......" Zhao Xingsheng scratched his increasingly thin head, after all, science students like to get to the bottom of the problem the most, and always have to figure out why, "Fortunately, I discussed this issue with your teacher, music ...... It's actually a complex science, including acoustics, vibrations, physiology, neuroscience, ......"

Hey, is that so? Gu Xiaobai, who originally had a contemptuous attitude towards music and felt that this was metaphysics at all, his eyes lit up and he sat up straight.

"If you want to understand music, you must first understand sound, sound is a sound wave that can be perceived by human hearing over a period of time, you have seen the oscilloscope, usually we can use the waveform of a sound wave to represent a sound. ”

"Music, on the other hand, is the distribution of countless sounds in time and space. Spatially, it is the pitch of the sound and the size of the sound field, and spatially, it is the continuation of time...... Therefore, music is something that can only be born in a multi-dimensional space. ”

"If you want to understand music, you need to understand four concepts: pitch, length, intensity, and timbre. ”

"For you science students, pitch, length, and intensity are all easy to understand, pitch is the frequency of sound vibration, sound length is the duration of the sound, sound intensity is the amplitude of the sound, and timbre is ...... Do you know the different sounds, why there is a timbre?"

Gu Xiaobai really didn't know, he had never learned anything about music.

"A vibrating object vibrates at a fixed frequency of its own, which is its fundamental wave, but at the same time it vibrates, one-half, one-third, one-quarter, one-fifth, and one-sixth of its places are also vibrating at the same time, emitting two, three, four, five, and six times the frequency of itself...... Harmonics of different frequencies. In terms of sound, we will call harmonics overtones, all overtones and fundamental tones are superimposed, and the ratio of overtones of different frequencies determines the timbre of a sound, for example, Xiaobai your treble, the treble overtones are very many and loud, so the same treble, you sing it, it sounds extraordinarily high-pitched, it's just explosive!"

Gu Xiaobai understood.

"With these four concepts in mind, I can explain to you what music is. Zhao Xingsheng turned around, took out an ipad pro from his backpack, opened a software called GarageBand, called up the interface of the piano, flipped to the position of C3, clicked down, and said to Xiaobai: "Music, or rhythm, is created based on frequency and human perception of frequency." This is C3, which is the legendary central C, and it is the one we use the most. GarageBand is a software that expands the vocal range downwards, and generally speaking, the center C we call will be marked as C4, and there are also large and small word groups, which is more complicated and is a problem left over from history...... But no matter how you mark it, you remember that this sound is the central C. ”

Zhao Xingsheng clicked a few times on the central C.

Gu Xiaobai nodded and remembered.

"According to international standards, the frequency of the center C is 262, and the benchmark of the piano is the A4 above the center C, and its frequency is 440."

"Here's the point...... The frequency of A5, which is an octave higher than it, is 880, and the A3, which is an octave lower than it, is 220......" Zhao Xingsheng said, "Xiaobai, let me ask you, why is the high-pitched do, for example, C5 and the low-pitched do, such as C3, so similar in sound? We sometimes sing, if the tone is too high or too low, replace it with a higher or lower octave, it is not contrary to harmony at all...... Why is that?"

Gu Xiaobai's eyes lit up: "Because the frequency between the treble do and the bass do is a multiple relationship, it can completely coincide with the overtones of the bass do!"

"That's right!" Zhao Xingsheng slapped his face.

Gu Xiaobai laughed out loud: "It turns out that music is completely a mathematical problem!"

Gu Xiaobai understood.