"Forget it, let me explain."


    Li Zhendong turned his head, took the microphone, solemnly explained to the reporter: "what is the cosmic string? A very fine and heavy unified field was born at the moment of the creation of the universe. It is a linear defect of phase transition! "


    Many reporters immediately opened their recording pens and pretended to be very serious.


    "It is divided into two types, one is a straight string across the universe, and the other is a ring string of various sizes. The collection of all strings forms a network full of the universe. "


    Theoretically, the distribution of cosmic strings in the universe is a bit like human neural networks, ranging from the Milky Way galaxy to the Virgo galaxy cluster, the Rania Kea supercluster, and even the entire observable universe.


    A picture appears on the screen, which is an observable universe of 96 billion light-years.


    This picture has not undergone any artistic processing. Any light spot in it represents a galaxy. In a way, the distribution of these galaxies is too much like a neural network.


    The reason why the universe will form a network system instead of spreading all matter evenly is because of the cosmic string.


    "Next, how to use cosmic strings to promote..."


    When cosmic strings were just born, these strings vibrated at a speed close to the speed of light, emitting huge gravitational radiation. But no matter how huge the energy is, it has been consumed in the form of gravitational radiation in more than 10 billion years.


    But there are also a few strings whose energy has not been consumed, which are hidden in the space for some special reasons. So there are not many strings that can be used.


    It is difficult to directly observe the existence of these strings. After all, it is a one-dimensional thing, with only length, no width and height.


    "... cosmic strings have great flexibility. If a string is tied to the earth, the earth can accelerate to 3000kmh in one second!"


    Hearing this, a female reporter asked curiously, "Professor Li, your statement seems a little strange... Isn''t the cosmic string not involved in electromagnetic interaction, so how should it be tied to the earth?"


    "Even if it can be tied to the earth to produce such great power, will the cosmic string not break? Strong interaction can''t bear such a force, can it? What does it consist of? "


    In full view of the public, Li Zhendong became the focus of everyone. He couldn''t help feeling a little comfortable, but he pretended to be serious and said, "I''m just making an analogy to let you understand the nature."


    "As a one-dimensional thing, it does not participate in electromagnetic interaction, and we can''t perceive it even around us. Like neutrinos, they can pass through our bodies without obstacles. "


    "So, how can we use it for propulsion? It can''t be the pull. The answer is... "


    "Gravity!"


    "But usually, we don''t seem to feel its gravity. What should we do? As I just said, it is a one-dimensional topological defect, which we can use. "


    "Professor Li, what is a topological defect?"


    "In short, defects caused by topological effects always exist in the homotopy sense. For example, there is a certain symmetry group in a system, and after the symmetry is broken, there will be a vacuum corresponding to the broken symmetry. "


    "... there is a transition state with very low energy from one vacuum to another. This situation is generally called soliton in academia, which is a topological defect. For a simple example, the magnetic chip of ferromagnetic system, because both ends correspond to good ferromagnetic phase, but the direction of M is different, which is two different vacuum... "


    Many reporters became noisy and complained loudly.


    So many technical terms, it is impossible to understand, even if you understand, it is impossible to write on the report.


    Li Zhendong felt very desperate. He looked back at Zhang Yuan with a smile and wondered how this guy dealt with reporters.


    "Don''t be impatient... In short, we can use a condensed matter method to reactivate the gravity of the dormant cosmic string."


    "For exactly how to do it, you can refer to the graviton shielding experiment on earth. There is something in common... That is, we need to break the gravitational balance. Of course, it''s just the gravity of a small cosmic string, only a few seconds or minutes. "


    He drew a simple image on the screen: a spaceship was sailing slowly, and there was a cosmic string in front of it. The airship suddenly launched a shell, which disturbed the dormant state of the cosmic string in front, making it start to vibrate slightly and emit huge gravity.


    "But this short period of time is enough. Think about it. If there is a huge gravity in front of the ship when it is sailing, will the whole ship be sucked?"


    "Of course, this section of gravity will disappear quickly, but the kinetic energy of the spacecraft, that is, the speed, has not disappeared."


    "Then we activate the string further ahead and repeat this process continuously. The speed of the spacecraft will be faster and faster!"


    This is a... New way to promote!


    This time, all the reporters understood.


    Gravitational propulsion and interstellar navigation


    Letter from the golden sun


    Humans on Kaptan


    After only half a day, this series of special reports soon triggered a big wave in the society. The information about the golden sun and the promotion of gravity have naturally become the most talked about topic.


    Originally a little slack of human beings, they have erupted a greater enthusiasm for work!


    Similar discussions can be heard in the streets.


    "The Kaptan star of the golden sun is so far away... Almost in two directions. The cosmic string in the middle is broken. We shouldn''t go there on purpose. "


    "For the first time, I should choose a closer star... At least I think so."


    "It doesn''t make much sense to meet the people of the golden sun."


    Even the Kunlun Mountains have to be slightly improved. After all, gravitational propulsion is much more optimized than traditional working medium propulsion, and there is no need to use most of the tonnage to load fuel. Therefore, some fuel warehouses in the whole Kunlun mountain can be modified into industrial areas, living areas and agricultural areas.


    Originally, the mass of fuel had to account for more than 70% of the whole spacecraft, but now it only needs to account for 20% of the mass. Even more radical, 10% is actually enough.


    This is the advantage of gravitational propulsion!


    Of course, gravitational propulsion also has certain limitations. Whether accelerating or decelerating, it should be carried out near the cosmic string. In this way, there are fewer stars to go. Not every star has a cosmic string to use.


    And conventional propulsion methods are still indispensable. Otherwise, the whole spaceship will not be able to move without being separated from the cosmic string?


    On the other hand, the devices that cause gravitational fluctuations are also under urgent research.


    Scientists have found a usable cosmic string near Gliese 581, which is absolutely great news!


    In other words, everything is ready, only due to the east wind of "Kunlun Mountain".