From 900 to 1904, he wrote a paper every year and published it in the German Journal of Physics. The first two articles are about liquids.
Surface thermodynamics and electrolysis try to give chemistry a mechanical basis. Later, I found that this road was impassable and turned to study heat.
Scientific mechanical basis, independent of J.W. Gibbs' work in 190 1 year, puts forward some basic theories of statistical mechanics, 190.
Two to 1904 all belong to this field. 1902 is calculated from the laws of mechanics and probability theory.
The heat balance theory and the second law of thermodynamics are derived. 1904 discusses the fluctuation predicted by statistical mechanics.
It is found that the energy fluctuation (or thermal stability of the system) depends on Boltzmann constant. Not only did he use this fruit
Mechanical system and thermal phenomenon, and boldly applied to radiation phenomenon to get the fluctuation formula of radiation energy, thus deriving Wien potential.
Immigration law. The study of wave phenomenon enabled him to engage in the research of radiation theory and molecular motion theory in 1905.
Major breakthrough.
1905 miracle
From 65438 to 0905, Einstein created an unprecedented miracle in the history of science. He wrote six papers in March this year.
During the half year ending in September, I used my spare time besides working 8 hours a day in the Patent Office to achieve four achievements in three fields.
An epoch-making contribution.
photon
1905 In March, he wrote the paper "A Speculative View on the Generation and Transformation of Light", which Planck put forward 1900.
The concept of quantum is extended to the propagation of light in space, and the optical quantum hypothesis is put forward, which is considered as follows: for time average (
That is, the statistical average phenomenon), the light fluctuates; For instantaneous values (that is, fluctuations), light appears as particles.
. This is the first time in history to reveal the unity of fluctuation of microscopic objects and particles, that is, wave-particle duality. then
The development of physics shows that wave-particle duality is the most basic feature of the whole microscopic world. This paper also puts l.bo.
Boltzmann's theory that "the entropy of a system is a function of its state probability" is named "Boltzmann principle". exist
At the end of the paper, he explained the photoelectric phenomenon with the concept of optical quantum, and deduced the maximum energy of photoelectrons.
And the frequency of incident light. It took 10 years for this relationship to be confirmed by R.A. Millikan's experiments. "Because of him.
Einstein won the Nobel Prize in Physics 192 1 year.
kinetic theory
1In April, May and February of 905, he wrote three theories about the motion of suspended particles in liquid. This sport is a British plant.
Scholar R. Brown first discovered it in 1827, and called it Brownian motion. Einstein's purpose at that time was to observe.
The random motion of suspended particles caused by the fluctuation of molecular motion can be used to determine the actual size of molecules to solve the problem.
For more than half a century, scientists and philosophers have been arguing about the existence of atoms. Three years later, the French physicist J.
B perrin confirmed Einstein's theoretical prediction with accurate experiments. This made Germany, which was the most firmly opposed to atomism at that time.
1908, F.W. ostwald, a chemist and founder of energetics, voluntarily announced: "The atomic hypothesis has become.
A scientific theory with a solid foundation.
Special relativity in the era of innovation
1June, 905, Einstein wrote a long article "On Electrodynamics of Moving Objects", which is relatively complete.
Put forward special relativity. This is the result of his exploration in 10, which largely solved the problems of 19 century.
The final crisis of classical physics promoted the revolution of the whole physics theory. In order to overcome the new experimental facts
The contradiction between the old theoretical systems, represented by the older generation of physicists, was put forward in order to fix the loopholes.
Numerous assumptions make the old theoretical system even more stretched. Einstein believes that the way out lies in the whole.
The theoretical basis has undergone fundamental changes. Starting from the belief of the unity of nature, he investigated such a problem: cattle
The general principle of relativity in the field of dynamics (the laws of mechanics are unchanged for any inertial system), why?
But not in electrodynamics? According to M Faraday's electromagnetic induction experiment, this inconsistency obviously does not exist.
The inherent problems of images must lie in the theoretical basis of classical physics. He learned transcendentalism from the empirical philosopher d Hume.
And e. Mach's criticism of I. Newton's concepts of absolute space and absolute time comes from the investigation of both in space.
Starting with the "simultaneity" of separation events, we deny the absolute simultaneity without empirical basis, and then deny the absolute.
For the existence of time, absolute space and "ether", it is considered that the traditional concept of time and space must be revised.
. He extended the relativity of mechanical motion discovered by Galileo, a basic experimental fact with universal significance, to all things.
Basic principles that all physical theories must follow; At the same time, all the light shown in the "Ether Drift" experiment is placed in a vacuum.
It is always based on a basic fact, that is, a certain speed c propagation. Keep the principle of relativity and the speed of light unchanged.
At the same time when the theory is established, the transformation between coordinates of different inertial systems can no longer be galilean transformation, but should be another one.
This transformation is similar to the transformation developed by Lorenz in 1904. In fact, Einstein didn't know Lorenz 19 at that time.
The works in 2004 are consistent with their original transformation form only in the first power of v/c; Xiansuo
Lorentz transformation actually refers to Einstein's form. For Lorentz transformation, the length of space and time is not
It is the same again, but the laws of physics, including Maxwell's equations, are the same (covariant). the original
Galilean transformation's covariant Newton's laws of mechanics must be modified under Lorentz transformation to satisfy covariant.
. This transformation is actually a generalization, which regards classical mechanics as a limit of relativistic mechanics at low speed.
Situation. So mechanics and electromagnetism are unified on the basis of kinematics.
Mass energy equivalent
1905 In September, Einstein wrote a short article, is the inertia of an object related to the energy it contains? ",for the phase.
A corollary of this theory reveals the equivalence of mass (M) and energy (E): E = MC 2, thus explaining radioactive elements.
The reason why elements (such as radium) can release a lot of energy. Mass-energy equivalence is related to nuclear physics and particle physics.
The theoretical basis also paved the way for the release and utilization of nuclear energy in the 1940s.
Further development of quantum theory
Einstein's theory of light quantum was opposed by almost all physicists of the older generation, even the first one.
Planck, the first quantum concept that enthusiastically supported special relativity, didn't seriously think it was love until 19 13.
A "mistake" of Einstein. Nevertheless, Einstein worked alone and developed quantum theory unremittingly.
Open. 1906, he extended the quantum concept to the vibration inside an object and basically explained the proportion of solids at low temperature.
Relationship between heat capacity and temperature. 19 12 years, he applied the concept of light quantum to photochemical phenomena and established photochemical laws.
19 16 He published a paper "On Quantum Theory of Radiation", which synthesized the development achievements of quantum theory and put forward some ideas about it.
The statistical theory of radiation absorption and emission comes from the concept of quantum transition in N Bohr 19 13.
Radiation formula. The concept of stimulated emission proposed in this paper provides a theory for the booming laser technology in the 1960 s.
Foundation. Inspired by the concept of wave-particle duality revealed by optical quantum theory, it was proposed by L.V. de Broglietti in 1923.
Matter wave theory. This theory was first enthusiastically supported by Einstein. Not only that, when he received the seal at 1924.
When he read the young physicist S Bose's paper on the statistical theory of light quantum, he immediately translated it into German and recommended it for publication.
Combining this theory with the concept of matter wave, the quantum statistical theory of monoatomic gas is put forward. This is about
Bose-einstein statistics obeyed by integer spin particles (see quantum statistics). Through Einstein's work
Enlightenment, e. Schrodinger extended de Broglie wave to bound particles and established wave mechanics at 1926 (see representation theory.
Quantum mechanics). Therefore, American physicist A. Pais believes that "Einstein is not only the three elders of quantum theory (referring to the general)
Frank, Einstein and Poe), and he is the only godfather of wave mechanics. "M. Born also believes that" in
In the struggle to conquer the wasteland of quantum phenomena, he was a "pioneer" and "our leader and standard bearer".
Exploring the equivalence principle of general relativity
After the establishment of the special theory of relativity, Einstein was not satisfied and tried to extend the application of the principle of relativity to non-relativity.
Inertial system. He found from Galileo that all objects in the gravitational field have the same acceleration (i.e. inertial mass and gravitational mass).
The same number of ancient experimental facts found a breakthrough, and 1907 put forward the equivalence principle: "The gravitational field is a parametric variable.
The equivalent strength of a photographic system is completely equivalent in physics. "Thus, in the gravitational field, the clock should go very fast.
The wavelength of light wave should be changed and the light should be bent. This year, his university teacher, the famous geometer H. Mincov.
Schicchi's four-dimensional representation of special relativity provides a useful mathematical tool for the further development of relativity.
It's a pity that Einstein didn't realize its value at that time and used it.
The tortuous course of continuing exploration
Einstein thought that the discovery of equivalence principle was the happiest idea in his life, but the future work was very difficult.
It's a big circle. 19 1 1 year, he calculated that light passes through the sun according to the equivalence principle and Huygens principle.
The near deflection value is □. At the beginning of 19 12, he analyzed the rigid rotating disk and realized how much he had gained in the gravitational field.
What is not strictly effective. At the same time, he also found that Lorentz transformation is not universal and needs to seek a more universal transformation relationship.
; In order to ensure the conservation of energy and momentum, the gravitational field equation must be nonlinear; The principle of equivalence exists only in an infinitesimal area.
Effective. He realized that the Gaussian surface theory he had learned in college should be useful for establishing the gravitational field equation, but he was not familiar with it.
A set of math tools can't be started at the moment. 19121kloc-0/0 in October, he left Prague and returned to work at his alma mater in Zurich. exist
With the help of M. Grossman, a classmate who was then a professor of mathematics at his alma mater, he studied Riemannian geometry and G.
Ritchie and T. Levi-Chevita's absolute differential calculus (tensor analysis). After a year of hard work, they agreed on 19 13.
In, he published an important paper, Outline of General Relativity and Gravity Theory, and put forward the gauge field gravity theory. here
, used to describe the gravitational field is not a scalar, but a metric tensor, that is, it takes 10 gravitational potential functions to determine the gravitational field.
. This is the first time that gravity and scale are combined to give Riemann a real physical meaning. But they have to do it.
The formula of gravitational field is covariant only for linear transformation and does not have any coordinates required by the principle of general relativity.
Covariance under transformation. This is because Einstein was not familiar with tensor operation at that time and mistakenly thought that as long as he insisted on conservation.
Law, we must limit the choice of coordinate system, in order to maintain the law of causality, we have to give up the requirement of universal covariation.
The second peak of scientific achievements
The three years from 19 15 to 19 17 are the second peak of Einstein's scientific achievements, similar to 1905.
He also made historic achievements in three different fields. Except 19 15, it was finally built as a human thought.
In addition to general relativity, one of the greatest achievements in history, in 19 16, the quantum theory of radiation was made as before.
The major breakthrough mentioned above, 19 17, initiated modern scientific cosmology. The Establishment and Abandonment of General Relativity
The error of generalized covariant requirement made Einstein continue to take a detour for more than two years until July 19 15.
Mistakes are gradually becoming known. After returning to the requirements of pan-covariant, he concentrated on exploring new quotations from June 19 15 to June 1 10.
On June 4th, June 1 1 and June 18, 25th, four papers were submitted to Prussian Academy of Sciences. In the first place
In a paper, he obtained the universal covariant gravitational field equation satisfying the conservation law (see general relativity), but added
An unnecessary restriction is that only unitary transformations are allowed. In the third paper, according to the new gravitational field equation, it is deduced that
It is calculated that the deflection of light passing through the surface of the sun should be □, which is twice the previous value; At the same time, it is also calculated that mercury is close
The residual age difference of the solar point every 100 year is 43□, which is completely consistent with the observation results, and completely solves the astronomical problem for more than 60 years.
Learning a big problem gave Einstein great encouragement. 1915165438+Paper "Field Equation of Gravity"1October 25th.
He gave up the unnecessary restriction on the transformation group, established the truly universal covariant gravitational field equation, and declared "generalization"
Relativity as a logical structure has finally been completed. "at the same time, the german mathematician D. Hilbert wrote in 19 15.
1October 20th, 165438+ In Gottingen, the universal covariant force field equation is also obtained independently. In the spring of 19 16, Einstein wrote
The paper "Fundamentals of General Relativity"; At the end of the same year, he wrote a very popular booklet, Narrow Sense.
And general relativity.
gravity wave
Einstein completed the summary of general relativity in March 19 16, and studied the approximate integral of gravitational field equation in June.
When a mechanical system changes, it will inevitably emit gravitational waves that travel at the speed of light. He pointed out that there was no radiation in atoms.
The existence of a stable orbit is mysterious, whether from the perspective of electromagnetism or gravity. Therefore, "quantum theory does not
Only Maxwell electrodynamics should be transformed, and so should the new theory of gravity. "Autumn, when he returned to quantum radiation.
When shooting the problem, he put forward the concepts of spontaneous transition and stimulated transition with this intention, and gave the Planck radiation formula
A new interpretation. The existence of gravitational waves has aroused the opposition of some scientists, and Einstein has repeatedly expressed his concern about its existence and nature.
Quality discussion. Gravitational waves are too weak to be detected and have not attracted people's attention for a long time. Since the 1960s,
The experiment of detecting gravitational waves has gradually formed a craze, but none of them have reached the minimum accuracy required for detection. Through the analysis of 1974
The periodic changes of the discovered radio pulse binary star PSR1913+16 were observed continuously for 4 years, and the indirect proof was published in 1979.
Aware of the existence of gravitational waves.
The establishment of cosmology
19 17 Einstein used the results of general relativity to study the space-time structure of the whole universe and published a groundbreaking paper.
Cosmological research based on general relativity. This paper analyzes that "the universe is infinite in space"
The traditional concept points out that it is incompatible with Newton's theory of gravity and general relativity; In fact, people don't
This method gives the reasonable boundary conditions of the gravitational field equation at infinity in space. He thinks the possible way out is to look at the universe.
It is a "self-enclosed continuous area with limited space (three dimensions)". Inference of scientific argument
Cosmology is limited and unbounded in space, which is a bold pioneering work in human history and makes cosmology get rid of pure conjecture.
Deterministic speculation, entering the field of modern science, is a revolution in the world outlook. According to the astronomical observation of stars at that time
The fact that the speed is very small, Einstein thinks that the distribution of matter is quasi-static. In order to ensure this condition, he is introducing
An unknown cosmological constant (cosmological term) is introduced into the force field. During this period, I had frequent correspondence with Einstein.
Dutch astronomer w de sitter proposed another model of the universe with zero average mass density. 1922 Soviet physicist
A.A. Friedman pointed out that the cosmological term is unnecessary, so it comes directly from Einstein's original results.
An expanding universe model with nonzero density of matter. Einstein disagreed at the time, but publicly withdrew his mistake a year later.
Wrong criticism, admit that Friedman's theory is correct. Since 1929 discovered the red shift of the spectral lines of extragalactic galaxies,
The theory of cosmic expansion has been strongly supported. After 1946, it developed into the big bang cosmology, and it has been so far.
The most successful cosmological theory.
The Long and Difficult Exploration of Unified Field Theory
After the completion of the general theory of relativity, Einstein still felt unsatisfied, so he wanted to extend the general theory of relativity to make it unsatisfied.
It includes not only gravitational field, but also electromagnetic field, that is to say, we should seek a unified field theory. He thinks this is the theory of relativity.
In the third stage of the exhibition, it is necessary to unify not only the gravitational field and electromagnetic field, but also the theory of relativity and quantum theory.
Together, it provides a reasonable theoretical basis for quantum physics. He hopes to get it in the unified field theory he is trying to establish.
The solution without singularity can be used to represent particles, that is, trying to explain the structure and quantum phenomenon of matter with the concept of field.
. The original unified field theory was popularized by mathematician H. Weil in 19 18.
Einstein appreciated this, but pointed out that the linear elements given by this theory are not constant, but accompanied by it.
It is related to history, which contradicts the fact that all hydrogen atoms have the same spectrum. Then, the mathematician T.F.E Kalucha
19 19, he tried to realize the unified field theory with five-dimensional manifold, which was highly praised by Einstein. 1922 Ain
Stan's first paper on unified field theory was about Karucha theory. After 1925, Einstein owned it.
Go all out to explore the unified field theory. In the first few years, he was very optimistic and victory was in sight; It turned out to be difficult.
Feeling that the existing mathematical tools are not enough; Exploration of 1928 to pure mathematics. He tried all kinds of methods,
Sometimes it is expressed in five dimensions, and sometimes it is expressed in four dimensions, but there is no real physical result.
In the 30 years from 1925 to 1955, apart from the completeness of quantum mechanics, gravitational waves and general relativity,
Except for sports, Einstein devoted almost all his scientific creative energy to the exploration of unified field theory. 1937
In 2000, with the cooperation of two assistants, he deduced the equation of motion from the gravitational field equation of general relativity, which further revealed.
The unity of space-time, matter and motion is a significant development of general relativity, and it is also Einstein's.
The last major achievement of scientific creation activities. However, he never succeeded in unifying the field theory.
. He has met with numerous failures, but he has never been discouraged and always starts from scratch with confidence. Because he is far from being fooled.
At that time, the mainstream of physics research, alone to overcome the problems that could not be solved at that time, plus his solutions in quantum mechanics.
On the issue of interpretation, it was in sharp opposition to the Copenhagen school, which was dominant at that time. Therefore, contrary to the situation in the 1920s.
He was physically isolated in his later years. But he is still fearless and unswervingly takes the road he has determined.
Exploring the road of truth, until the day before his death, he was still preparing to continue his mathematical calculation of unified field theory in his hospital bed.
He realized in 1948, "I can't finish this work; It will be forgotten, but it will be rediscovered in the future
. "The development of history has not failed him, because a series of experiments in the 1970s and 1980s strongly supported the unified theory of weak electricity.
The idea of unified field theory shows its vitality in a new form and provides great opportunities for the future development of physics.