Physics in 1900
Einstein's early papers all come from attempts to demonstrate that atoms exist and have a finite nonzero size. At the time of his first paper in 1902, it was not yet completely accepted by physicists that atoms were real, even though chemists had good evidence ever since Antoine Lavoisier Antoine-Laurent de Lavoisier , the father of modern chemistry, was a French noble prominent in the histories of chemistry and biology. He stated the first version of the law of conservation of mass, recognized and named oxygen (1778) and hydrogen (1783), abolished the phlogiston theory, helped construct the metric system, wrote the first extensive's work a century earlier. The reason physicists were skeptical was because no 19th century theory could fully explain the properties of matter from the properties of atoms.
Ludwig Boltzmann Ludwig Eduard Boltzmann was an Austrian physicist famous for his founding contributions in the fields of statistical mechanics and statistical thermodynamics. He was one of the most important advocates for atomic theory when that scientific model was still highly controversial was a leading 19th century atomist physicist, who had struggled for years to gain acceptance for atoms. Boltzmann had given an interpretation of the laws of thermodynamics, suggesting that the law of entropy increase is statistical. In Boltzmann's way of thinking, the entropy is the logarithm of the number of ways a system could be configured inside. The reason the entropy goes up is only because it is more likely for a system to go from a special state with only a few possible internal configurations to a more generic state with many. While Boltzmann's statistical interpretation of entropy is universally accepted today, and Einstein believed it, at the turn of the 20th century it was a minority position.
The statistical idea was most successful in explaining the properties of gases. James Clerk Maxwell James Clerk Maxwell was a Scottish theoretical physicist and mathematician. His most significant achievement was the development of the classical electromagnetic theory, synthesizing all previous unrelated observations, experiments and equations of electricity, magnetism and even optics into a consistent theory. His set of equations—Maxwell's, another leading atomist, had found the distribution of velocities of atoms in a gas, and derived the surprising result that the viscosity Viscosity is a measure of the resistance of a fluid which is being deformed by either shear stress or extensional stress. In everyday terms , viscosity is "thickness." Thus, water is "thin," having a lower viscosity, while honey is "thick" having a higher viscosity. Viscosity describes a fluid's internal resistance to of a gas should be independent of density. Intuitively, the friction in a gas would seem to go to zero as the density goes to zero, but this is not so, because the mean free path of atoms becomes large at low densities. A subsequent experiment by Maxwell and his wife confirmed this surprising prediction. Other experiments on gases and vacuum, using a rotating slitted drum, showed that atoms in a gas had velocities distributed according to Maxwell's distribution law.
In addition to these successes, there were also inconsistencies. Maxwell noted that at cold temperatures, atomic theory predicted specific heats that are too large. In classical statistical mechanics Statistical mechanics is the application of probability theory, which includes mathematical tools for dealing with large populations, to the field of mechanics, which is concerned with the motion of particles or objects when subjected to a force. It provides a framework for relating the microscopic properties of individual atoms and molecules to, every spring-like motion If F is the only force acting on the system, the system is called a simple harmonic oscillator, and it undergoes simple harmonic motion: sinusoidal oscillations about the equilibrium point, with a constant amplitude and a constant frequency has thermal energy kBT on average at temperature T, so that the specific heat Specific heat capacity, also known simply as specific heat, is the measure of the heat energy required to increase the temperature of a unit quantity of a substance by a certain temperature interval. The term originated primarily through the work of 18th-century physicist Joseph Black who conducted various heat measurements and used the phrase & of every spring is Boltzmann's constant The Boltzmann constant is the physical constant relating energy at the particle level with temperature observed at the bulk level. It is the gas constant R divided by the Avogadro constant NA: kB. A monatomic solid with N atoms can be thought of as N little balls representing N atoms attached to each other in a box grid with 3N springs, so the specific heat of every solid is 3NkB, a result which became known as the Dulong–Petit law. This law is true at room temperature, but not for colder temperatures. At temperatures near zero, the specific heat goes to zero.
Similarly, a gas made up of two atoms can be thought of as two balls on a spring. This spring has energy kBT at high temperatures, and should contribute an extra kB to the specific heat. It does at room temperature, but at low temperature, this contribution disappears. At zero temperature, all other contributions to the specific heat from rotations and vibrations also disappear. This behavior was inconsistent with classical physics.
The most glaring inconsistency was in the theory of light waves. Continuous waves in a box can be thought of as infinitely many spring-like motions, one for each possible standing wave A standing wave, also known as a stationary wave, is a wave that remains in a constant position. This phenomenon can occur because the medium is moving in the opposite direction to the wave, or it can arise in a stationary medium as a result of interference between two waves traveling in opposite directions. In the second case, for waves of equal. Each standing wave has a specific heat of kB, so the total specific heat of a continuous wave like light should be infinite in classical mechanics. This is obviously wrong, because it would mean that all energy in the universe would be instantly sucked up into light waves, and everything would slow down and stop.
These inconsistencies led some people to say that atoms were not physical, but mathematical. Notable among the skeptics was Ernst Mach Ernst Mach (February 18, 1838–February 19, 1916) was an Austrian physicist and philosopher, remembered for his contributions to physics such as the Mach number and the study of shock waves. As a philosopher of science, he was a major influence on logical positivism and through his criticism of Newton, a forerunner of Einstein's relativity, whose logical positivist philosophy led him to demand that if atoms are real, it should be possible to see them directly.[27] Mach believed that atoms were a useful fiction, that in reality they could be assumed to be infinitesimally small, that Avogadro's number The Avogadro constant is the number of "elementary entities" (usually atoms or molecules) in one mole, that is (from the definition of the mole), the number of atoms in exactly 12 grams of carbon-12. It was originally called Avogadro's number. The 2006 CODATA recommended value is: was infinite, or so large that it might as well be infinite, and kB was infinitesimally small. Certain experiments could then be explained by atomic theory, but other experiments could not, and this is the way it will always be.
Einstein opposed this position. Throughout his career, he was a realist. He believed that a single consistent theory should explain all observation, and that this theory would be a description what was really going on, underneath it all. So he set out to show that the atomic point of view was correct. This led him first to thermodynamics, then to statistical physics, and to the theory of specific heats of solids.
In 1905, while he was working in the patent office, the leading German language physics journal Annalen der Physik Many very important articles about scientific discoveries have been first published in the journal, including Albert Einstein's Annus Mirabilis Papers in 1905 that provide much of the foundation of modern physics published four of Einstein's papers. The four papers eventually were recognized as revolutionary, and 1905 became known as Einstein's "Miracle Year Annus mirabilis is a Latin phrase meaning "wonderful year" or "year of wonders" . It was used originally to refer to the year 1666, but is today also used to refer to different years with events of major importance such as 1905 when Albert Einstein published his breakthrough four articles on Physics. Some examples:", and the papers, as the Annus Mirabilis Papers The Annus Mirabilis Papers are the papers of Albert Einstein published in the "Annalen der Physik" scientific journal in 1905. These four articles contributed substantially to the foundation of modern physics and changed views on space, time, and matter. The Annus Mirabilis is often called the "Miracle Year" in English or in.
Main article: Annus Mirabilis Papers The Annus Mirabilis Papers are the papers of Albert Einstein published in the "Annalen der Physik" scientific journal in 1905. These four articles contributed substantially to the foundation of modern physics and changed views on space, time, and matter. The Annus Mirabilis is often called the "Miracle Year" in English or in Albert Einstein, 1905, The Miracle Year. On 30 April, 1905, Einstein completed his thesis with Alfred Kleiner Alfred Kleiner was Professor of Experimental Physics at the University of Zürich, and was Albert Einstein's doctoral advisor or Doktorvater. Initially Einstein's advisor was H. F. Weber. However, they had a major falling out, and Einstein chose to switch to Kleiner, Professor of Experimental Physics, serving as pro-forma advisor. Einstein was awarded a PhD Doctor of Philosophy, abbreviated PhD , for the Latin philosophiæ doctor, meaning "teacher of philosophy", or alternatively, DPhil, for the equivalent doctor philosophiæ, is an advanced academic degree awarded by universities. In many English-speaking countries, the PhD is the highest degree one can earn and applies to graduates in a by the University of Zurich. His dissertation was entitled A New Determination of Molecular Dimensions. [28]<<Table of Contents Albert Einstein (pronounced /ˈælbərt ˈaɪnstaɪn/; German: [ˈalbɐt ˈaɪ̯nʃtaɪ̯n] ; 14 March 1879 – 18 April 1955) was a theoretical physicist. He is best known for his theories of special relativity and general relativity. Einstein received the 1921 Nobel Prize in Physics "for his services to Theoretical Physics, and especially | Next>> | Show All>>
