The universe is all that is an object, and it includes all time and space; The past, the present, the future, and the place that we saw did not see and knew, and did not know. The universe is the one that includes all matter and energy, and all the laws of nature that combine them, and it contains every possible life and every place in which life can exist. In this universe, according to the Big Bang model, about 13.8 billion years ago everything began; From a very hot explosion with a temperature known as the Planck temperature, which is the highest possible temperature, and nothing in this universe has reached it except for the universe itself after the Big Bang in a very, very short time known as the Planck time of 10-43 seconds, and the amount of Planck temperature is 1032 Kelvin. In contrast, the highest temperature reached by humans in 2012 was 5.5 trillion (5,500,000,000,000) Kelvin at the Large Hadron Collider to study the behavior of matter in conditions similar to those conditions after the Big Bang. Certainly, matter will behave differently at that high temperature, and the traditional laws of physics will change starting from the Planck temperature, in addition to the different behavior of matter at very low temperatures, and it will show a very distinctive and useful behavior.
The temperature of the universe today
The temperature inside the sun is approximately 15 million Kelvin, and it decreases as we go outside to reach 5800 Kelvin at the surface of the sun. The sun is like all stars in its size and age. The temperature decreases as we move away from its center, and it decreases more and more as we move away from the galaxy. The temperature in the vast space between galaxies is 2.735 K; Where this number was obtained through measurements of the cosmic microwave background radiation (in English: Cosmic Microwave Background Radiation).
Lowest temperature recorded
One of the lowest recorded temperatures in the universe is located in the vast void between galaxies as we mentioned, and you are probably thinking that 2.735 K is the lowest temperature ever recorded. Indeed, this temperature is very cold, as it is only 2.735 degrees above absolute zero (absolute zero). is -273.15 degrees Celsius), but although it is the lowest natural temperature, much colder temperatures have been recorded!
One of the coldest natural objects observed in the universe is the Boomerang Nebula, which is located within the constellation Centaurus, about 5,000 light-years away from us. Where scientists found in 1997 that the temperature of the gases emitted from the center of the dying star after it had expanded and cooled had reached one-kelvin degree above absolute zero. The nebula maintains this lower temperature as a cosmic refrigerator in space.
Scientists have been able to measure the coldest temperature ever recorded, which is 100 pico Kelvin (0.000,000,000,1 Kelvin), which is human-made, as it was using the inverse Carnot cycle that the refrigerator was made, and to obtain such a temperature it would need an atomic refrigerator, and it was recorded in Low-Temperature Laboratory located in Finland by cooling radium metal, which was done not only for cooling but for the study of the magnetic nucleus of the radium element, as radium metal itself becomes a superconductor at the transition temperature Known to all elements, a superconductor is a material that has no resistance, that is, the current will flow in it forever without the need for a battery permanently, which is like a liquid that does not have internal friction, as it will continue to flow forever.
The coldest spot in the universe
This project was planned to start in 2016 by NASA, which will create the coldest spot in the universe inside the International Space Station using an atomic refrigerator that cools down to a temperature of 100 pK to study materials at these temperatures, as the concepts of matter Solid, liquid, and gaseous are no longer valid here, as the matter is close to zero energy, which generates new properties of matter. Rather, it constitutes a new form of matter, which is "quantities", and these quantum obey quantum mechanics to a large extent, and in A stage, when samples of the same substance are collected in one place, they will not mix as we know from our daily dealings with the matter, but rather they will overlap as waves overlap, this is what is known as “matter waves”.
What distinguishes the International Space Station and makes it the best place to make the coldest spot in the universe is that it will be easy to cool there, and this is because of the weakness of gravity there, as it is a basic principle in thermodynamics that when the gas expands, it will cool, just as it happens when you spray deodorant, The compressed gas is very small in size, to the point that it is liquid inside the package, and when it comes out of the package it is cold, and this is because you allowed it to expand by opening a small port in the package.
There is nothing colder than absolute zero (0 Kelvin), which is the only temperature you can never reach because when you reverse the Carnot cycle you do work to cool down, and the lower you want to get the more work you need, which It means that if you wanted to get the temperature of absolute zero, you would need an infinite amount of work, which is absolutely impossible.