One talked aboutTime stands still, a lot of people will be contactedBlack holesBlack holes have a boundary called the event horizon, and when matter or information passes through this boundary, the objects appear to the outside observer to stay on the event horizon forever, i.e., time appears to "stop".
But you know what? In our real microcosm, time is the same as thatTemperatureTightly linked. Both theoretically and experimentally derived,Time can be stopped completely
Albert Einstein in the special theory of relativityIt has been proposedUnity of time and spaceconcept, and inGeneral relativityIt also profoundly demonstrates the interrelated and inseparable nature of time, space and matter. In this sense, the essence of time is actually a unit of measurement to measure the speed of an object's motion.
So,To stop time, you have to stop moving the object, which means that the kinetic energy is zero。At the microscopic level, we can hardly find matter that is not in motion, and scientists would sayThe temperature reaches absolute zero(-273 degrees Celsius.)15 or Kelvin temperature scale 0k),Time will also stand still
InAbsolute zero, the particle kinetic energy of the matter is minimal, theoretically reaching the lowest possible state of thermal motion, whileThe vibrations, rotations, and other forms of thermal motion of microscopic particles (e.g., molecules, atoms) cease almost completely
In this microcosm, the material system exhibits a high degree of staticThere, time no longer counts
InThe early days of the universeMicroscopic particles(e.g., quarks, leptons, photons, and other elementary particles).Random motion at extremely high temperatures at speeds close to the speed of light, their kinetic energy forms part of the total energy of the system.
As the universe gradually cools and expands, the speed of microscopic particles also slows down, causing the temperature of the universe to gradually decrease, which in turn leads to the interaction and condensation of different particles, and finally forms atoms, molecules, and macroscopic celestial structures.
YesAstrophysicist**, the theory of permanent expansion allows oursThe universe stopped in 5 billion years。With the extreme expansion and dilution of the universe, the temperature in most places will beExtremely close to absolute zero
As the universe continues to expand and cool, effective energy exchange and transformation processes will become increasingly scarce until the universe enters an extremely stable and static state, which we call it"Heat death"., at which point the available energy in the universe will be extremely dispersed and thinComplex structures and the existence of life are no longer supported, and time is infinitely close to static
In scientific experiments in various countries, although it has been possible to reach extremely low temperatures very close to absolute zero, inIt is impossible to achieve absolute zero at all in real experiments, because according toThe Third Law (Neisel-Clapperon Law)., the entropy of the system cannot be reduced to absolute zero in a finite number of steps.
Despite this, scientists from all over the world are still enjoying this research.
Nobel Prize in PhysicsSteven Chu, a Chinese-American physicist, developed laser cooling technology in the early 1980s.
In 1995,Massachusetts Institute of TechnologyWolfgang Kettler succeeded in achieving Bose-Einstein condensation, and they won the 2001 awardNobel Prize in Physics
Harvard UniversityResearchers have used advanced cooling techniques and quantum gas experiments to create the closest possible temperature record to absolute zero known at the time, such as inTens of Nakelvin (NK).within the scope of the .
July 2021,Research in Physics, Chinese Academy of SciencesThe self-developed helium-free dilution refrigerator has been successfully realized10 milli-kelvin (mk, 0 degrees above absolute zero.)01 degree) below extremely low temperatures.
Scientists continue to explore and cool the experimental system to a state close to absolute zero through a variety of advanced technologies such as dilution refrigeration and laser coolingProfound significanceInBasic scientific researchSuperconductivity researchQuantum computing and quantum information processingThere is great value in areas such as precision measurement
In short, although absolute zero cannot be achieved in reality, experimental research infinitely close to absolute zero is of great value for deepening our understanding of the basic laws of nature and promoting the development of cutting-edge science and technology.