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Otto Lummer
Otto Richard Lummer (17 July 1860 – 5 July 1925) was a German physicist and researcher. He was born in the city of Gera, Germany. With Leon Arons, Lummer helped to design and build the Arons–Lummer mercury-vapor lamp. Lummer primarily worked in the field of optics and thermal radiation. Lummer's findings, along with others, on black body radiators led Max Planck to reconcile his earlier Planck's law of black-body radiation by introducing the quantum hypothesis in 1900. In 1903, with Ernst Gehrcke, he developed the Lummer–Gehrcke interferometer. Lummer died in former Breslau, now Wrocław Wrocław is a city in southwestern Poland, and the capital of the Lower Silesian Voivodeship. It is the largest city and historical capital of the region of Silesia. It lies on the banks of the Oder River in the Silesian Lowlands of Central Eu .... References External links * {{DEFAULTSORT:Lummer, Otto 1860 births 1925 deaths People from Gera 19th-century German physi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gera
Gera () is a city in the German state of Thuringia. With around 93,000 inhabitants, it is the third-largest city in Thuringia after Erfurt and Jena as well as the easternmost city of the ''Thüringer Städtekette'', an almost straight string of cities consisting of the six largest Thuringian cities from Eisenach in the west, via Gotha, Erfurt, Weimar and Jena to Gera in the east. Gera is the largest city in the Vogtland, and one of its historical capitals along with Plauen, Greiz and Weida, Thuringia, Weida. The city lies in the East Thuringian Hill Country, in the wide valley of the White Elster, between Greiz (upstream) and Leipzig (downstream). Gera is located in the Central German Metropolitan Region, approximately south of Saxony's largest city of Leipzig, east of Thuringia's capital Erfurt, west of Saxony's capital Dresden and 90 km (56 miles) north of Bavaria's city of Hof (Saale). First mentioned in 995 and developing into a city during the 13th century, Gera has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermal Radiation
Thermal radiation is electromagnetic radiation emitted by the thermal motion of particles in matter. All matter with a temperature greater than absolute zero emits thermal radiation. The emission of energy arises from a combination of electronic, molecular, and lattice oscillations in a material. Kinetic energy is converted to electromagnetism due to charge-acceleration or dipole oscillation. At room temperature, most of the emission is in the infrared (IR) spectrum, though above around 525 °C (977 °F) enough of it becomes visible for the matter to visibly glow. This visible glow is called incandescence. Thermal radiation is one of the fundamental mechanisms of heat transfer, along with conduction and convection. The primary method by which the Sun transfers heat to the Earth is thermal radiation. This energy is partially absorbed and scattered in the atmosphere, the latter process being the reason why the sky is visibly blue. Much of the Sun's radiation tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
19th-century German Physicists
The 19th century began on 1 January 1801 (represented by the Roman numerals MDCCCI), and ended on 31 December 1900 (MCM). It was the 9th century of the 2nd millennium. It was characterized by vast social upheaval. Slavery was abolished in much of Europe and the Americas. The First Industrial Revolution, though it began in the late 18th century, expanded beyond its British homeland for the first time during the 19th century, particularly remaking the economies and societies of the Low Countries, France, the Rhineland, Northern Italy, and the Northeastern United States. A few decades later, the Second Industrial Revolution led to ever more massive urbanization and much higher levels of productivity, profit, and prosperity, a pattern that continued into the 20th century. The Catholic Church, in response to the growing influence and power of modernism, secularism and materialism, formed the First Vatican Council in the late 19th century to deal with such problems and confirm ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
People From Gera
The term "the people" refers to the public or common mass of people of a polity. As such it is a concept of human rights law, international law as well as constitutional law, particularly used for claims of popular sovereignty. In contrast, a people is any plurality of persons considered as a whole. Used in politics and law, the term "a people" refers to the collective or community of an ethnic group or nation. Concepts Legal Chapter One, Article One of the Charter of the United Nations states that "peoples" have the right to self-determination. Though the mere status as peoples and the right to self-determination, as for example in the case of Indigenous peoples (''peoples'', as in all groups of indigenous people, not merely all indigenous persons as in ''indigenous people''), does not automatically provide for independent sovereignty and therefore secession. Indeed, judge Ivor Jennings identified the inherent problems in the right of "peoples" to self-determination, as i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1925 Deaths
Events January * January 1 – The Syrian Federation is officially dissolved, the State of Aleppo and the State of Damascus having been replaced by the State of Syria (1925–1930), State of Syria. * January 3 – Benito Mussolini makes a pivotal speech in the Italian Chamber of Deputies (Italy), Chamber of Deputies which will be regarded by historians as the beginning of his dictatorship. * January 5 – Nellie Tayloe Ross becomes the first female governor (Wyoming) in the United States. Twelve days later, Ma Ferguson becomes first female governor of Texas. * January 25 – Hjalmar Branting resigns as Prime Minister of Sweden because of ill health, and is replaced by the minister of trade, Rickard Sandler. * January 27–February 1 – The 1925 serum run to Nome (the "Great Race of Mercy") relays diphtheria antitoxin by dog sled across the U.S. Territory of Alaska to combat an epidemic. February * February 25 – Art Gillham records (for Columbia Re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1860 Births
Events January * January 2 – The astronomer Urbain Le Verrier announces the discovery of a hypothetical planet Vulcan (hypothetical planet), Vulcan at a meeting of the French Academy of Sciences in Paris, France. * January 10 – The Pemberton Mill in Lawrence, Massachusetts collapses, killing at least 77 workers. * January 13 – Battle of Tétouan, Morocco: Spanish troops under General Leopoldo O'Donnell, 1st Duke of Tetuan defeat the Moroccan Army. * January 20 – Camillo Benso, Count of Cavour is recalled as Prime Minister of Piedmont-Sardinia. February * February 20 – Canadian Royal Mail steamer (1859) is wrecked on Cape Sable Island, Nova Scotia, on passage from the British Isles to the United States with all 205 onboard lost. * February 26 – The 1860 Wiyot Massacre, Wiyot Massacre takes place at Tuluwat Island, Humboldt Bay in northern California. * February 26, February 27 – Abraham Lincoln makes his Cooper Union speech, Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ernst Gehrcke
Ernst J. L. Gehrcke (1 July 1878 in Berlin – 25 January 1960 in Hohen-Neuendorf) was a German experimental physicist. He was director of the optical department at the Reich Physical and Technical Institute. Concurrently, he was a professor at the University of Berlin. He developed the Lummer–Gehrcke method in interferometry and the multiplex interferometric spectroscope for precision resolution of spectral-line structures. As an anti-relativist, he was a speaker at an event organized in 1920 by the Working Society of German Scientists. He sat on the board of trustees of the Potsdam Astrophysical Observatory. After World War II, he worked at Carl Zeiss Jena, and he helped to develop and become the director of the Institute for Physiological Optics at the University of Jena. In 1949, he began work at the German Office for Materials and Product Testing. In 1953, he became the director of the optical department of the German Office for Weights and Measures. Education Gehrcke studi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
History Of Quantum Mechanics
The history of quantum mechanics is a fundamental part of the History of physics#20th century: birth of modern physics, history of modern physics. The major chapters of this history begin with the emergence of quantum ideas to explain individual phenomena—blackbody radiation, the photoelectric effect, solar emission spectra—an era called the Old or Older quantum theories. Building on the technology history of classical mechanics, developed in classical mechanics, the invention of wave mechanics by Erwin Schrödinger and expansion by many others triggers the "modern" era beginning around 1925. Paul Dirac's relativistic quantum theory work led him to explore quantum theories of radiation, culminating in quantum electrodynamics, the first quantum field theory. The history of quantum mechanics continues in the history of quantum field theory. The history of quantum chemistry, theoretical basis of chemical structure, chemical reaction, reactivity, and chemical bond, bonding, inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Planck's Law
In physics, Planck's law (also Planck radiation law) describes the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium at a given temperature , when there is no net flow of matter or energy between the body and its environment. At the end of the 19th century, physicists were unable to explain why the observed spectrum of black-body radiation, which by then had been accurately measured, diverged significantly at higher frequencies from that predicted by existing theories. In 1900, German physicist Max Planck heuristically derived a formula for the observed spectrum by assuming that a hypothetical electrically charged oscillator in a cavity that contained black-body radiation could only change its energy in a minimal increment, , that was proportional to the frequency of its associated electromagnetic wave. While Planck originally regarded the hypothesis of dividing energy into increments as a mathematical artifice, introduced merely to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Max Planck
Max Karl Ernst Ludwig Planck (; ; 23 April 1858 – 4 October 1947) was a German Theoretical physics, theoretical physicist whose discovery of energy quantum, quanta won him the Nobel Prize in Physics in 1918. Planck made many substantial contributions to theoretical physics, but his fame as a physicist rests primarily on his role as the originator of Quantum mechanics, quantum theory and one of the founders of modern physics, which revolutionized understanding of atomic and Subatomic particle, subatomic processes. He is known for the Planck constant, which is of foundational importance for quantum physics, and which he used to derive a set of Unit of measurement, units, today called Planck units, expressed only in terms of fundamental physical constants. Planck was twice president of the German scientific institution Kaiser Wilhelm Society. In 1948, it was renamed the Max Planck Society (Max-Planck-Gesellschaft) and nowadays includes 83 institutions representing a wide range ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black-body Radiation
Black-body radiation is the thermal radiation, thermal electromagnetic radiation within, or surrounding, a body in thermodynamic equilibrium with its environment, emitted by a black body (an idealized opaque, non-reflective body). It has a specific continuous spectrum that depends only on the body's temperature., Chapter 13. A perfectly-insulated enclosure which is in thermal equilibrium internally contains blackbody radiation and will emit it through a hole made in its wall, provided the hole is small enough to have a negligible effect upon the equilibrium. The thermal radiation spontaneously emitted by many ordinary objects can be approximated as blackbody radiation. Of particular importance, although planets and stars (including the Earth and Sun) are neither in thermal equilibrium with their surroundings nor perfect black bodies, blackbody radiation is still a good first approximation for the energy they emit. The term ''black body'' was introduced by Gustav Kirchhoff in 1860. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optics
Optics is the branch of physics that studies the behaviour and properties of light, including its interactions with matter and the construction of optical instruments, instruments that use or Photodetector, detect it. Optics usually describes the behaviour of visible light, visible, ultraviolet, and infrared light. Light is a type of electromagnetic radiation, and other forms of electromagnetic radiation such as X-rays, microwaves, and radio waves exhibit similar properties. Most optical phenomena can be accounted for by using the Classical electromagnetism, classical electromagnetic description of light, however complete electromagnetic descriptions of light are often difficult to apply in practice. Practical optics is usually done using simplified models. The most common of these, geometric optics, treats light as a collection of Ray (optics), rays that travel in straight lines and bend when they pass through or reflect from surfaces. Physical optics is a more comprehensive mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
