Deep Space Fleet

After Lin Xuanxuan heard Zhang Yuan's narration, she was silent for a long time, and suddenly said, "The relationship between your boys is often more pure. If I were you, I would have been crying for a long time ..."

星星 A star drifted from the light cluster in the back, drawn a complicated curve, and transferred to the light cluster in front. This is because the spacecraft is sailing at high speed.

"On the contrary, the relationship in our dormitory is not very harmonious. You know, there are always such small frictions between girls. If there is a girl's private life in chaos, the entire dormitory will be smoky. Everyone will form their own small Groups, I don't know how complicated it is. "

"I haven't heard you talk about it."

Xuan Lin Xuan Xuan said: "In fact, nothing, everything passed ... Finally, we were near graduation, everyone ate a meal and then dispersed. The new hatred and the old hatred all disappeared. There is no chance to meet again."

Zhang Yuanyuan said: "It's no pity. In fact, the connection between people is not as close as imagined. Sometimes you are not allowed to go to parties, and you are too lazy to go. In your life, one or two friends is enough."

Lin Xuanxuan pondered for a while, "Ah, yeah, what are their names, I can't remember them anymore! What a pity, I can't even remember the look of my mother."

"I can't remember what my father looks like ... I can only recall the photos," Zhang Yuan sighed.

I was so silent for a while.

Lin Xuanxuan asked again, "... If I die suddenly, will you cry?"

"What are you crying for?" Zhang Yuan laughed and said, "Death is the beginning of a whole new one. This cycle is over, and a new life will start again. It is not meaningful to miss the past."

"I can only wish you happiness and happiness in the new world, and enjoy your next life!"

Xuan Lin Xuan Xuan was surprised at first, and then smiled: "May you also have a bright future in the future world!"

Uh ...

In the last few years, Zhang Yuan has been working at the Observatory. He is mainly responsible for teaching elementary and junior high school students how to use astronomical telescopes and how to identify planets in the universe, including the direction of the sun and the direction of Glize 581. It was the place where the former parent star, human beings were born, or developed here.

"If one day you become captains, it would be miserable if you could not find your way home!"

工作 This job is easy, there is not much workload, and I am happy every day.

A clever little girl asked: "Grandpa Zhang, how should navigation in the universe be positioned? The galaxy is in motion, everything is in motion. How should we determine the position of our spaceship?"

"Even planes on the planet need navigation. How can a spacecraft navigate? Long-distance navigation must be accurate enough!"

In the face of this problem, Zhang Yuan thought about it and took another sip of water: "It's very simple, there are 3 good ways in total."

"First, use an accelerometer and gyroscope, which is an inertial navigation system. By measuring the acceleration and angular velocity at each moment, you can use the integral to calculate the speed and displacement of the aircraft. However, the disadvantage of inertial navigation is also obvious: the longer the time , The larger the error, so it is only suitable for short range and auxiliary positioning. "

"The second method uses known relative positions of celestial bodies to locate, observe surrounding stars, and set of simultaneous equations. But as you said, everything is moving, and the distance measured by the spectrum is constantly changing, and Hard to measure very accurately. "

"Method three, navigation through a fixed radio signal source is also the method we use now. There are a large number of pulsars in the universe, which periodically emit electromagnetic pulses. As long as multiple pulsars are observed, a pulsar timing array is formed. It's a natural deep space network, also known as the 'Galactic Positioning System.' "

"If you feel that the pulsars in the Milky Way are moving, causing a certain degree of error, you can even observe pulsars outside the Milky Way, 100 million light years away!"

"A planet so distant, we can directly think of it as stationary."

Zhang Yuan broadcasted several images of pulsars on the screen. These pulsars are equivalent to artificial satellites that constantly send signals to the outside world.

These students are stunned in the face of truly complex knowledge.

The girl asked again, "If we go out of the Milky Way and sail across the river, how should we position ourselves?"

Zhang Yuan replied: "There is a phenomenon called fast radio storms. These high-energy millisecond flashes are speculated that their signal source is very huge and may come from outside the Milky Way. Maybe one day in the future, they will become a human cross Lighthouses for galaxy travel. These high-energy millisecond flashes are speculated that their signal source is very huge, possibly from outside the Milky Way. Maybe one day in the future, they will become beacons for humans to travel across the river. "

"Crossing the river ?!"

As soon as I thought that there were so many natural lighthouses in the universe, all the students were yearning for it, and they couldn't help looking out the window.

It's too far across the river!

"Grandpa Zhang, there is a question, why are there as many integers and even numbers?"

After a while, a little fat man who just went to junior high school asked again.

名 His name is Wang Tiantian, I do n’t know where I heard about this knowledge, whether it ’s astronomy, geography, mathematical chemistry, or almost everything.

Little children worship power, and knowledge is power. In their eyes, Zhang Yuan is the most knowledgeable person, and he is the old captain of the past. He has a gentle temper and can basically answer all the content. . You can even play computer here, so there are always many children gathered at the observatory.

"This problem is too complicated!" Zhang Yuan laughed and talked about the "infinity" problem with the children of this age, it was still too difficult.

I wondered for a while, and he said, "Do you think there are more points on the 1 cm line segment or more points on the 2 cm line segment?"

当然 "Of course ... there are more dots on the 2 cm line segment! 2 cm is longer than 1 cm, shouldn't there be more dots on top!" The fat man was nervous, this is not a very simple question ...

I was ashamed of being wrong.

The students around Wu also took it for granted, and there were still a few clever people who were crooked and didn't speak.

Zhang Yuan laughed and said, "Have you learned a function once?"

"Of course I learned."

那么 "So, can 3x images be drawn?"

图像 This image is very simple, it is a straight line at an angle of 60 degrees to the x-axis.

Zhang Yuan intercepted 1 cm on the x-axis of the abscissa, which corresponds to the oblique section exactly 2 cm. He said with a smile: "According to this function image, the points on the abscissa and the points on the oblique line are not the same. Does it correspond to one, from (0,0) to (1, √3), which is exactly 2 cm. Each x-axis coordinate can correspond to one. "

"What you call a 2 cm line segment has more points. Where are the extra points?"

如果 "If you can't find it, we can only think that there are as many points on the 1 cm line segment as there are as many points on the 2 cm line segment, right?"

The little fat man looked unconvincedly to find the disappearing points, but how could he not find it ...

In the end, I launched a mass offensive and started a fallacy, like "whether the cycle of 0.9 equals 1" came out, but in the end, I could only lose it very unwillingly.

"Can't find it, haha!"

Zhang Yuan said gleefully: "In fact, according to our theory, one-to-one correspondence is a very important means. There are as many points on a centimeter line segment as there are 2 cm points; according to one method, one There are as many centimeter points as there are points on a piece of paper, that is, on a plane.

"Even a point of one centimeter is as large as a point on the surface of the Kunlun Mountain spacecraft, or even a point in the entire universe ... even any point in a high-dimensional space is as many, and can be corresponding one by one by some methods. . "

"That is, there are as many points on a centimeter line segment as there are points in the entire universe!"

"Ah?" Not only this little fat man, but also a lot of students behind him exclaimed.

How could they never have imagined that such a small section can be compared with the entire universe. Is this too incredible?

Letting these children show a startled expression and lament the mystery of the universe has become a great pleasure for Zhang Yuan.

远 Zhang Yuan laughed: "But infinity is also divided into sizes. The set of natural numbers, mathematically called Aleph 0, is the smallest infinity."

"The smallest infinity?"

"The number of points on a line segment, that is, an infinite set of real numbers, is called Aleph 1."

"... all possible mathematical functions: the number of continuous and discontinuous functions, call it Aliev 2."

"I see, there are Alev 3, Alev 4, Alev 5!" The little fat man shouted loudly, and seemed to find something full of power.

Students of this age are always so-secondary, have acquired a little knowledge, and can show off in front of their peers.

Zhang Yuan laughed: "Yes, it can extend to infinity ... But you can hardly find a higher dimensional infinity. In reality, it can only become a string of symbols on paper. And, mathematics The difficulty is whether there is an infinite number that is greater than Aliev 0 and smaller than Aliev 1. This problem is called the continuum hypothesis. "

"Although the continuum hypothesis is a hypothesis, it can never be proven or negated. It has been left there alone, for almost four thousand years, and it has not been resolved."

"Why?" Wang Tiantian asked again, this world is too strange.

A problem has not been solved for four thousand years. He's a little bit nervous inside

Zhang Yuan laughed again and again: "That's ... another story, called Gödel's incompleteness theorem! The history of mathematics is another magnificent journey. There are so many problems that cannot be solved in the world. Then! "

Uh ...

Time passes day by day. As the aging continues, the body is not as good as the day.

Even when I go to the observatory, I will feel very tired, but he still insists on working and answering the doubts of the children. This can be said to be the greatest pleasure of the friends after they die.

On this day, the doctor who examined his body showed a very regretful expression, she said very carefully: "Old Captain, your physical condition has reached the standard for entering the virtual world."

"I'll help you write a report, and your wife has reached the standard. At the end of this month, if you want ..."

"Is that so ... really live long enough." Zhang Yuan nodded and sighed: "Nothing unwilling, let me say goodbye to this era."

On August 29, 5812, the first captain of the Kunlun Mountain Fleet, Zhang Yuan, was about to leave the world.

The salute salute lighted up briefly in this starry sky and disappeared silently.

Currently 90% of the population is hibernating, and there is no need to wake up specifically. The remaining 10% of the sober population all spontaneously performed this farewell ceremony.

Many production activities in Kunlun Mountain have also stopped, and the school has a day off, and Zhang Yuan deserves this honor.

"Do you have anything else to say?" Said the doctor.

Countless offspring are watching him, expecting something from him, or encouragement, or something else. There are also old people who are constantly wiping tears. This time, he is not the last one to leave.

"No, everyone is fine, move on." Zhang Yuan said with a smile: "It depends on you in the future."

Hold a few staff members, lift him from the wheelchair and lie down.

Hibernation warehouse is like a soft Simmons, lying very comfortable, Zhang Yuan turned his head and looked around.

曾经 A former friend and colleague is saying goodbye to him.

I also seem to have few.

This feeling is very subtle, Zhang Yuan is not a person who is afraid of death, but at this moment, there is still a feeling of breathlessness.

He suddenly remembered--

At a very young age, when he understood what death was about, he squatted beside the corner and wept.

"Can I not die?" Zhang Yuan asked wryly.

"What does it mean to die?" His father Zhang Qiming replied.

"It's ... always alive."

"Oh, you mean ... you want to live forever." Faced with this problem, Zhang Qiming pondered for a long time and said solemnly: "I think it is better to die. People can't live forever."

Young Zhang Yuan was unable to accept this answer for a while, although many answers from his father were inexplicable.

Zhang Qiming said: "I think that you are likely to imagine the time period of eternal life is too short. Eternal life means infinite, one hundred years, ten thousand years, 100 million years, or even ten billion billion years ~ www.mtlnovel. com ~ is indistinguishable from zero. "

"In the eyes of true eternal life, the universe may be dead within a second, that is, you feel all the happiness on the earth, and only exist for a very short time. The next is long, in the vast The time of solitude in the open universe. There is no substance and no company. "

直到 "Until waiting in the quantum sea, that little cosmic explosion, restart a new era. But how much time does this take?"

"This loneliness may not be able to be endured by human beings, or the thinking mode may become another species, or stop thinking ... I think, stop thinking and choose death." Zhang Qiming looked at the blue sky and touched Zhang Far head, said seriously.

Even though, the young Zhang Yuan did not understand what his father was saying ...

I don't know why, Zhang Yuan remembered this conversation before leaving the world.

Maybe, dead heroes are good heroes.

I just ... how lonely ...

Among the beautiful flowers, Zhang Yuan faintly heard crying. I don't know who is crying.

Unconscious, he soon lost consciousness.

Uh ...

An era is over, and another era is just beginning.

Humans will not stop their footsteps because of this, this great journey continues ...

,