The principle of superconductivity is easy to understand.

Metals and some other materials are turning superconductive in low temperatures. The superconductivity is the result of the lack of oscillation of the object. And that thing makes objects superconducting. There is also a second way to make an object superconducting. 

That thing is increased pressure. And an extremely high pressure ends the oscillation in metal. The problem is that the needed pressure is over 20 thousand times the atmosphere. And if there is a lean in the system that can cause a dangerous situation. The combination of low temperature and high pressure can make it possible to create superconductors that are operating at higher temperatures than ever before. 

The third way is to use plasma or a magnetic field that is pushing the wires as normal pressure does. In that case, the magnetic fields are making it possible to create superconducting at room temperature. 

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The thing that makes the object superconductive is that its atoms are close to each other. So they act like a stick when an electron hits them. 

In normal material, those atoms are like balls they would pull energy out from electron that moves between them. But in superconducting objects, the energy travels in atoms' quantum fields. 

In superconducting entirety, they form a thick entirety. When an electron hits those atoms it hits their quantum fields it pushes the quantum field or atom forward. 

So the entire line of atoms is moving forward. And then it sends the quantum forward. Because the electron pushes the entire atom line that acts like a stick forward that thing doesn't cause resistance. 

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But the thing that makes the object superconductive is that there is no loose space between those particles. The atoms are pressed extremely close to each other. And that means they cannot move anywhere when an electron hits them. So the energy travels through that object without any resistance. 

Resistance is the thing that is caused when energy travels in the object. And the atoms are swinging when their quantum field swings like jelly. That swing requires energy. And that energy is out from electrons that are traveling at the core of the electric wire. 

When atoms are packed close to each other they can transmit energy in the form of wave motion. When an electron hits those atoms it will push the entire atom line. And then that atom line sends the quantum to another side of it. That thing removes resistance between those atoms. 

https://scitechdaily.com/holy-grail-of-energy-efficiency-physicists-advance-in-race-for-room-temperature-superconductivity/