Science or Myth - Superconductivity Phenomenon

Ravasi's prophecy:

In 1784, British chemist Ravasi predicted that if the Earth suddenly entered a cold region, air would no longer exist in the form of an invisible fluid, and it would return to a liquid state. Since then, Lavoisier's prophecy has been inspiring people to achieve gas liquefaction and thus achieve extremely low temperatures. Making gas into liquid sounds like a myth, but scientists not only believe in this myth, but also make it a reality.

At the end of the 18th century, when Ravasi made his predictions, the level of scientific research was still very low, and we cannot imagine today how difficult it was for scientists to liquefy gases at that time. Many people have put in a lot of effort and dedication, dedicating their entire lives to this, but their efforts have finally paid off.

In the 1830s, scientists discovered that some gases could be liquefied by pressurization, and indeed, gases such as hydrogen sulfide, hydrogen chloride, and sulfur dioxide could be turned into liquids. However, gases such as oxygen, hydrogen, and nitrogen showed no signs of liquefaction. In the following decades, people's main focus was on them. Aime sealed oxygen and nitrogen in a specially designed cylinder and sank 1.6 kilometers into the seabed, causing the pressure to exceed 200 standard atmospheres; A doctor named Natler from Vienna also manufactured a container that could withstand 3000 standard atmospheres to liquefy air, but none of them were successful. Faced with this reality, many people feel that humans will never be able to liquefy such gases and believe that they are truly 'permanent gases'.

But even so, humans have not stopped their efforts to liquefy 'permanent gases'. In 1877, French physicist Gallard first achieved the liquefaction of oxygen in a "permanent gas", with liquid oxygen temperatures as low as -140 ℃. In 1898, British scientist Dewar obtained liquefied hydrogen with a temperature of -252.76 ℃. The following year, Dewar successfully transformed liquid hydrogen into solid hydrogen, with a temperature as low as -260 ℃.

While obtaining low temperature through liquefied gases, scientists have also developed another temperature scale for measuring temperature - the Kelvin scale. The Celsius temperature scale we usually use is 273.16 degrees higher than the Kelvin temperature scale, so the zero degree in the Kelvin temperature scale is -273.16 ℃. In 1968, Dutch physicist Onnis made a greater breakthrough in gas liquefaction research. He successfully liquefied the most difficult to condense helium gas, achieving a low temperature of almost 0K - - or -273.16 ℃. At this point, humanity has finally fully realized Lavasir's prophecy.

An astonishing discovery:

Humans have achieved low temperatures through liquefied gases. What will scientists do with low temperatures? They have a lot to do, and the most important one is to continue exploring that ancient problem and studying what changes will occur in lifeless substances at low temperatures.

In 1910, Onnis began studying changes in state of matter under low-temperature conditions with his students. In 1911, while studying the relationship between mercury resistance and temperature changes, they found that the resistance of mercury, which had already solidified into a solid state, suddenly decreased and approached zero when the temperature was below 4K, which shocked Onnis. The resistance of mercury would disappear without a trace, and even the most imaginative scientists at the time did not expect this phenomenon to occur at low temperatures.

To further confirm this discovery, they used solid mercury to create a loop and caused a magnet to pass through the loop to generate an induced current. Under normal circumstances, as long as the magnet stops moving, the current in the loop will immediately disappear due to the presence of resistance. But when the mercury loop is at a low temperature below 4K, even if the magnet stops moving, the induced current still exists. How long can this peculiar phenomenon last? They insist on regular measurements, and after a year of observation, they have concluded that as long as the temperature of the mercury loop is below 4K, the current will persist for a long time without any signs of weakening.

Subsequently, Onnis conducted experiments on various metals, alloys, and compound materials at low temperatures, and found that many of them exhibited the phenomenon of resistance disappearance and long-term induced current at low temperatures. Due to the fact that conductors have resistance under normal conditions, Onnis referred to the phenomenon of losing resistance at low temperatures as superconductivity. After achieving a series of successful experiments, Onnis immediately officially announced this discovery, which quickly attracted high attention from the scientific community. Onnis was also awarded the Nobel Prize in Physics in 1913.