Science and Technology Daily reporter Lu Chengkuan
the use of scientists in our country
Quantum entanglement? Quantum decoherence? In fact, it is not difficult to understand them. Let's make such a metaphor:
Compare the two particles entangled together to a couple in love, at this time, they are lingering together, you have me in your heart, I have you in my heart. Even if thousands of miles away, still miss each other. That's itQuantum entanglement。
Next, let's assume that the couple's yearnings for each other can be quantified. For example, they are in a period of passionate love, and their yearnings for each other are 100 points. Unfortunately, however, a beautiful woman has recently appeared beside the man. They have a good conversation with each other. Gradually, the man has a feeling for the woman. Then, the new beauty has disturbed this couple's entanglement.
Over time,DecoherenceAs the man's feeling towards his girlfriend fades away, the couple's missing becomes less and less. Finally, when the man breaks up, the couple will be free from entanglement.
Pan Jianwei team of China University of Science and Technology and other domestic and foreign researchers cooperate to make use ofThis is the first time in the world that quantum satellites are used to test the theory of combining quantum mechanics with general relativity in the gravitational field of the earth.The results of the study were published in the Journal of Science on September 20, Beijing time.
The scene of satellite-ground experiments carried out by Ali Earth Station and Mozi satellite. The green light is the beacon light emitted by the satellite, and the red is the beacon light emitted by the ground.
Quantum mechanics and gravity theory are the two pillars of modern physics. They have achieved great success in their respective fields. But any theoretical work that tries to integrate them has encountered great difficulties.
Among the four basic interactions known at present, electromagnetic, weak interaction and strong interaction have been quantized and unified. Only the quantification of gravitational interaction has been unresolved, and the solution, or a correct understanding of this problem, will contribute to the establishment of a unified theory of the four basic interactions. This is one of the most important issues concerned by many scientists in physics, including Einstein.
In the experiment scenario, in order to improve the intensity of the signal light, three devices were used to work together. Two telescopes in the picture simultaneously emitted beacons to the satellite.
At present, there are many models about how to integrate quantum mechanics and gravity theory, but they are lack of experimental tests and can not be verified, which seriously hinders the development of science. One of the main reasons is that the predictions of these theoretical models can only be tested under extreme experimental conditions, such as on a minimal spatial scale.negtive thirty fiveM, specific electron radius-15The rice is 20 orders of magnitude smaller, or a very high energy standard.SixteenTeV (trillion electron volts), and the current large Hadron Collider such as LHC can only increase the energy of protons to the order of 10 TeV, which far exceeds the experimental conditions that can be achieved at present.
General relativity foretells a class of strange space-time structures, which may violate the law of causality.
However, the destruction of causality by time machine will lead to many logical paradoxes. In order to avoid this problem, Polchinski, a famous American physicist, first put forward a theoretical solution. He pointed out that there is a special and self-consistent evolution process of classical objects in this kind of space-time structure, and there is no logical paradox. American physicist Politzer and British physicist Deutsch et al extended the theory and studied the self-consistent evolution behavior of quantum states in this kind of space-time structure.
Ali Ground Station Telescope for Quantum Communication with Mozi
On this basis, Australian physicist Raf et al. further proposed a call.
Suppose a pair of entangled photonic pairs are prepared on the earth's surface, one of which propagates through the local flat space-time and propagates near the surface of the light source, while the other propagates to the satellite through the curved space-time formed by the Earth's gravitational field. According to the existing quantum mechanics theory, all entangled photonic pairs will maintain entanglement properties; and according to the basis of the existing quantum mechanics theory, all entangled photonic pairs will maintain entanglement properties.
The experimenter and the scene of star-to-ground docking between Ali Ground Station and Mozi
Quantum science experimental satellite is an ideal platform to test this theory. Pan Jianwei's team has carried out a series of innovative experimental studies on the quantum state distribution between terrestrial stars. On August 16, 2016, China launched the world's first quantum science experimental satellite.
Ali Ground Station Telescope under Delayed Photography for Quantum Communication with Mozi
This is the first experimental study on the relationship between quantum mechanics and gravity theory carried out by satellites in space, which has the significance of index and guidance, and will greatly promote the related theoretical and experimental research activities.
One of the beauty of scientific research is thatSource: Pictures and videos in Sci-tech Daily articles provided by the authorEditor: Zhang Shuang (internship)