Emdrive can be understood in two ways Understanding mode I David Kipping, an astronomer at Columbia University, published a paper proposing that spacecraft designed with light sails can theoretically use black holes to achieve a speed close to the speed of light. In this paper, Kipping uses a double black hole system model to realize the advanced acceleration and deceleration of spacecraft with the help of kinetic energy transfer based on light Sail Technology in the double black hole system. The principle is shown in the figure above. The photon emitted by the laser emitter is accelerated by the gravitational field of the moving black hole in the two hole system. Specifically, because photons have measurable static mass, we can launch photons towards the predetermined orbit near the black hole, so that photons can accelerate around the orbit "for one week" by the gravitational field of the black hole, and then hit the "light sail" of the spacecraft, so that the spacecraft can obtain a photon acceleration effect much more powerful than the laser emitter, High efficiency and large acceleration and deceleration can be realized by using the double hole system. The effect of this process is that the relative position of the black hole and the laser source has changed. This system can also be used to explain the principle of emdrive. When the laser is replaced by microwave, the effect of accelerating photons is replaced by weakening the intensity of microwave. After replacing with microwave, the effect is that the gap between the particles of the whole set of emdrive (including microwave source) becomes larger, that is, thermal expansion, and a microwave source emits a force in the opposite direction (the force cannot be measured in other directions). Understanding mode 2 According to the principle of light sail, photons have a certain mass, momentum and speed. Light can produce weak thrust on matter and low light. Typical band transition, photons have the effect of acceleration and deceleration, making the light sail move. Light sail can be verified by a large number of engineering examples. What's enough to explain emdrive? According to NASA's paper, it is considered that the thrust actually measured by emdrive is at least two orders of magnitude greater than the microwave light pressure. But will this emdrive be a light pressure amplifier? How does emdrive amplify the thrust? As shown above, in particles (electrons, ions, or lattices?) In the microwave field, particles can obtain energy and radiate energy, and the radiated energy and momentum are directly stored in the cavity of emdrive. Because of the asymmetric effect, it works externally and obtains thrust. Practice leads to truth, and all our assumptions and inferences can be tested and analyzed with experiments. Based on understanding method 1, we can design a larger cavity and install the cavity in a huge pool. There are dozens of tons of water in the pool, which emits microwaves in the direction of gravity. By increasing the particle space of water in the pool, the forward thrust is obtained. If the microwave emission direction is changed, the thrust direction can be changed. It shows that this explanation is true. The understanding of mode 1 is summarized in one sentence: Microwave steering produces external thrust. Based on the understanding of mode 2, according to the distribution of electromagnetic field generated by the cavity, holes shall be opened at the appropriate position of the cavity to prevent the cavity from being in the pool or water vapor, and glass or plastic shields shall be added inside the cavity to prevent water molecules outside the cavity from entering. Through more reasonable electromagnetic field distribution, the ability of microwave directional order to do work on particles can be expanded. Increase the external thrust. The second understanding is summarized in one sentence: the selective directional acceleration and deceleration of particles in the microwave field generates external thrust. In the phenomena of nuclear fusion, nuclear fission and annihilation of positive and negative particles, the movement of matter is produced. Most of the material laws of transmitting motion have been well known, and it is impossible to realize without working fluid engine in current people's cognition. Then whether it can be separated from the macro entity of particles and transfer this source of motion (i.e. material motion caused by nuclear fusion, fission and annihilation of positive and negative particles). If it can be explained, can it be considered that non working medium propulsion is only the motion generated by motion sources such as nuclear fusion, nuclear fission and annihilation of positive and negative particles to achieve macro entities, and can realize controllable motion in space without particle separation like chemical rocket and electric propulsion? In the current cognition, it is considered impossible if it is separated from the source of material transmission movement. It may be that microwave, thermal radiation and light are also substances. The use of the law of conservation of energy needs to be considered. Time division should be considered for thermal radiation, microwave and systematic energy conservation. Emdrive may meet the conservation of momentum after considering microwave, thermal radiation and other factors, forward and backward of time.