Ma Yiyi is very slender, with a height of nearly 1.7 meters, only more than 80 pounds, and the price is that the lordosis is not warped.

So it's nothing to squeeze with her, a chair can sit down.

It's just that Ma Yiyi called Gu to play, originally under the guise of self-study together, chatting by the way.

Now it's so crowded, it's a little awkward to read a book, so I'm too lazy to act, let's talk directly.

It was a cold winter, and everyone was wearing a lot of clothes, which were relatively bloated, and Ma Yiyi also wore a down jacket.

But the library is air-conditioned, and it's relatively warm, so everyone hangs their coats on the back of their chairs when they get inside.

Ma Yiyi wore a pure white cashmere sweater, and because there was no noise in the library, the two sides could only get close to each other and chat at a volume close to whispering.

Ma Yiyi leaned into Gu Yu's ear: "You haven't answered me yet, are you free tomorrow?"

Gu Yu laughed softly: "What, do you want to surprise me and invite me to dinner." ”

Ma Yiyi patted him: "I want to go with you to register for a driver's license, otherwise who is patient to remember your birthday......!

In a university where there are more men and fewer women, it is still a rare beauty in the Academy of Mathematical Sciences for many years, and it is too embarrassing to let the girl take the initiative to chase after her.

So Ma Yiyi's reserved scale is still very good, and she can only do this step.

"Let's go together, didn't you say you were going to go back to learn to drive during the winter vacation? Gu Yu couldn't understand it.

Ma Yiyi: "That's not Futaba is not yet 18 years old! So I can only retreat, how can I let a girl learn to drive alone!"

In the 99 years on the Blue Hole, the penetration rate of private cars was about the same as that of the zero years on Earth, and even in the first-tier metropolises, the proportion of private cars was less than 10%.

In second-tier cities such as Jindu and Fangzhou, it is estimated that only one in thirty or forty households can have a car, so it is still quite rare for a girl to learn a driver's license.

Gu Yu didn't say anything more, this matter was decided.

There was no topic, and the atmosphere was awkward for a while, so everyone had to come up with the topic and sit together to read the book and do the question. Ma Yiyi took the initiative to softly ask Gu Play for two complex variable functions, and Gu Play also tried her best to speak in writing without affecting the classmates next to her.

The white cashmere on Ma Yiyi's body, at the distance of whispering, gradually tickled Gu Yu, and he couldn't help but want to sneeze.

Ma Yiyi's face gradually turned pink, gradually spreading from the root of her ears to her cheeks, it should have been the breath blown out by Gu Yu when she whispered, blowing the hair around her ears and tickling her earlobes.

Gu Yu suddenly wondered if the girl was deliberately seizing the time in the library to create an opportunity for him.

After completing the two complex functions, two muffled whispers suddenly came from the side, and then there was a sound of packing the schoolbag.

"Damn! I can still beep on my own in the library. ”

"How ladylike she is, it's not that she takes the initiative to take advantage of her when she sees Gao Fu and is handsome. ”

Gu Yu turned his head to look, it turned out to be a middle-to-low looking sturdy girl in the seat next door, who couldn't stand this kind of dog food, and then got up angrily, packed up his things, and didn't want the position.

A boy on the other side of the table was also infected, and only lasted an extra minute or two, and then packed up his things.

Of course, it is not excluded that the boy himself is not determined to learn, and he can't stick to it after studying for a while, and he wants to go to an Internet café.

Gu Yu was slightly embarrassed, but he was a boy after all, so he quickly sat in the vacated position of the girl who was poisoned by the pseudo-dog food.

Ma Yiyi's face was even more unbearable, and she couldn't leave, her face was red and glamorous, and she wanted to cry, so she could only bite her lip and insist.

This matter, strictly speaking, is indeed a loss for Gu Play and Ma Yiyi, after all, the library is not allowed to speak in the first place, even if you try to keep your voice down as much as possible, as long as the person next to you says that he heard it, it is the person who spoke is at a loss.

The two of them didn't dare to say a word, and they did more than an hour of stuffy questions before they got through the embarrassment. Gu Yu saw that the time had passed half past twelve, and there would be no more dishes if he didn't go to the cafeteria to eat, so he poked Ma Yiyi: "Let's eat first." ”

Ma Yiyi breathed a sigh of relief, and then got up.

Gu Yu picked up his schoolbag and followed behind.

"Keep the schoolbag to occupy the position, do you want to grab the position again?" Ma Yiyi was angry and reminded in a low voice.

She felt that she had been sprayed just now, and she had to blame Gu for not taking a position.

Gu Yu explained: "Just leave the book to occupy the space, and it is better to carry a notebook in the bag." ”

Ma Yiyi didn't really want to be angry with him with a cold face, but she was afraid that it would be embarrassing to show intimacy with Gu Play, so Gu Play gave her the stairs, and she took the opportunity to change the topic and complained:

"When I see you, you don't really come to study, and you bring a computer to the library!"

Gu Play: "I'm tired of doing questions, I occasionally change my brain, I've been writing a book recently, a manuscript from the National Science and Technology Publishing House." ”

"Really? Let me read it later?"

"No problem, just look at it. ”

The two quickly forgot the embarrassment of being sprayed with dog food just now.

When she arrived at the cafeteria, Ma Yiyi made a tomato scrambled egg, fried mutton with green onions, and three fresh dishes, and sat opposite Gu You.

While eating, Ma Yiyi suddenly asked: "Do you think that motivated girls look particularly snobbish?"

Gu Yu was eating a piece of fat intestine in his mouth, very tough and not too bitten, he quickly took a few bites, swallowed it and drank a mouthful of soup before replying: "Why do you think so? Let's put it this way, do you think the boy's motivation has anything to do with snobbery?"

Ma Yiyi actually thought about it seriously: "It doesn't seem to be a ...... No, that's because boys are motivated on their own. ”

Gu Play: "Isn't it true that girls are motivated by themselves?"

Ma Yiyi: "I also rely on myself to improve......"

Gu Yu is more wooden in this aspect, after all, he is just a technosaur on the earth, so he did not delve into this topic further.

After Ma Yiyi finished eating, she felt a little depressed, and when she was bored, she proposed to take care of the manuscript.

The lunch rush hour has also passed, and the cafeteria is originally open all day, so there will be no rush. Gu Yu took out his notebook, opened his manuscript, Ma Yiyi moved a position, sat down next to him from him, and then read it carefully.

"What kind of subject is this?" Ma Yiyi became curious just by reading the title.

But after thinking about it carefully, she vaguely remembered that since Gu Wan's debut, the scientific research projects and scientific discoveries and observations she has participated in seem to be really connected with this title.

Gu Wan's discovery of the lowest cosmic microwave background radiation has increased the age of the universe by four or five billion years, and this achievement is closely related to the theme of "physical time".

As for the cesium atomic clock, it was originally a timekeeping tool that exhaustively studied the limits of physics.

Therefore, writing such a topic, those fans who play well on the Internet should sell it.

Gu Wan's original intention, of course, was to directly write the best-selling popular science book on the planet, Hawking's "A Brief History of Time". There is no Hawking in this world anyway.

But the problem is that he knows very well that the popular science community is also senior.

If you want to study history, you have just become an associate professor, what qualifications do you have to write "General History of China"? You can only write about a certain dynasty and a certain generation. You have to become a master to write grand topics without being sprayed or suppressed.

The same is true of the popular science community, so after thinking about it, he chose this "Order of Time" on the premise that he didn't want to waste Hawking's "A Brief History of Time".

This book, written by the famous Italian physicist Carlo Rowelli on Earth, is more specialized than Stephen Hawking's "A Brief History of Time", and only discusses some small points of the problem of time, which is simple and intuitive. It is more suitable as an entry-level popular science monograph.

Of course, Ma Yiyi wouldn't know that Gu played so many twists and turns, so she just read down patiently.

"More than 2,000 years ago, the son said on the river: The deceased is like a husband, reluctant to give up day and night. This is the most basic feeling of the ancients about events, believing that time will flow evenly in one direction, from the past to the present and to the future......

However, this feeling, just as the ancients thought that the earth seemed to be flat and that the rising sun and stars seemed to revolve around the earth, was just prejudice.

Since Albert Einstein, physicists have discovered that the appearance of time in the objective world is completely different from the way humans perceive time. To this day, we can even say in the sense that time does not exist at all......"

The introduction at the beginning is very easy to understand, elegant and vulgar, and people who have no physical foundation can understand it, but the conclusion is shocking enough:

Time does not exist objectively, it is just an artificial variable set by human beings in order to understand the world.

Then, in the argumentation stage, Gu Wan quoted the cesium atomic clock project he participated in in the first chapter, which was very pertinent and made the book very convincing.

"Is there a time in the universe? No, based on basic physics since Einstein, you see me and hear me, not actually who I am now, but minus the time it takes for light to travel from me to you.

The Proxima Centauri you see four light-years away from Earth is Proxima Centauri four years ago. The cesium atomic clock you receive from the GPS satellite is 30 milliseconds before the chronograph.

The theory of relativity tells us that time and space cannot be discussed separately, and that each time should correspond to a specific spatial position, and then talk about the 'present', so there is no unified 'now' in the universe.

Our effective range of 'now' in the context of a low-speed environment depends on precision. If the accuracy is nanoseconds, the effective space corresponding to 'now' is only a few meters, and if the accuracy is milliseconds, the effective space corresponding to 'now' can be thousands of kilometers......"

What Gu Wan wrote was just an outline, a skeleton, and there were many arguments and examples that were not filled in.

So Ma Yiyi saw this part, although she felt a bit subversive, but she could understand it, and it was very clear:

Corresponding to the simple worldview of the ancients, the illusion that "time is uniform and universal", the two points of "uniformity" and "universality" have been very easily broken.

The rest is to break the illusion of "passing".

"Time, isn't it 'passing'? This can be leveraged?" Ma Yiyi felt that she was gradually unable to understand.