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Big Crunch
The Big Crunch is a hypothetical scenario for the ultimate fate of the universe, in which the expansion of the universe eventually reverses and the universe recollapses, ultimately causing the cosmic scale factor to reach absolute zero, an event potentially followed by a reformation of the universe starting with another Big Bang. The vast majority of current evidence, however, indicates that this hypothesis is not correct. Instead, astronomical observations show that the expansion of the universe is accelerating rather than being slowed by gravity, suggesting that a Big Freeze is much more likely to occur. Nonetheless, some physicists have proposed that a "Big Crunch-style" event could result from a dark energy fluctuation. The hypothesis dates back to 1922, with Russian physicist Alexander Friedmann creating a set of equations showing that the end of the universe depends on its density. It could either expand or contract rather than stay stable. With enough matter, gravity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Energy Density
In physics, energy density is the quotient between the amount of energy stored in a given system or contained in a given region of space and the volume of the system or region considered. Often only the ''useful'' or extractable energy is measured. It is sometimes confused with stored energy per unit mass, which is called ''specific energy'' or . There are different types of energy stored, corresponding to a particular type of reaction. In order of the typical magnitude of the energy stored, examples of reactions are: Nuclear power, nuclear, Chemical energy, chemical (including Electrochemistry, electrochemical), electrical, pressure, Deformation (engineering), material deformation or in Electromagnetic field, electromagnetic fields. Nuclear reactions take place in stars and nuclear power plants, both of which derive energy from the binding energy of nuclei. Chemical reactions are used by organisms to derive energy from food and by automobiles from the combustion of gasoline. Liqu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bentley's Paradox
Bentley's Oyster Bar and Grill is a seafood restaurant at 11-15 Swallow Street, London, which opened in 1916. The restaurant, previously known as Bentley's, has always specialised in oysters and seafood, and serves classic British dishes under the stewardship of Chef Richard Corrigan. History Twentieth Century Bentley's Oyster Bar was opened in 1916, by William "Bill" Bentley. An entertainer whose true passion was musical stand-up comedy, Bill founded the West Cliff Theatre, an open-air theatre in Clacton, alongside the entertainers Bernard Russell and Bert Graham. During the war, Bill's wife, Ethel Rose, with whom he shared five sons, convinced him to invest in oyster beds in West Mersea. The success of this led him to selling oysters from an oyster barrow by the pier in Clacton-on-Sea, and then opening Bentley's Oyster Bar and Grill in 1916. The restaurant did not stop his urge to perform, and up until 1934, he caught the early morning commuter train up to town, returning on t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atheism
Atheism, in the broadest sense, is an absence of belief in the Existence of God, existence of Deity, deities. Less broadly, atheism is a rejection of the belief that any deities exist. In an even narrower sense, atheism is specifically the position that there no deities. Atheism is contrasted with theism, which is the belief that at least one deity exists. Historically, evidence of atheistic viewpoints can be traced back to classical antiquity and Nāstika, early Indian philosophy. In the Western world, atheism declined after Christianity gained prominence. The 16th century and the Age of Enlightenment marked the resurgence of atheistic thought in Europe. Atheism achieved a significant position worldwide in the 20th century. Estimates of those who have an absence of belief in a god range from 500 million to 1.1 billion people. Atheist organizations have defended the autonomy of science, freedom of thought, secularism, and secular ethics. Arguments for atheism range from p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isaac Newton
Sir Isaac Newton () was an English polymath active as a mathematician, physicist, astronomer, alchemist, theologian, and author. Newton was a key figure in the Scientific Revolution and the Age of Enlightenment, Enlightenment that followed. His book (''Mathematical Principles of Natural Philosophy''), first published in 1687, achieved the Unification of theories in physics#Unification of gravity and astronomy, first great unification in physics and established classical mechanics. Newton also made seminal contributions to optics, and Leibniz–Newton calculus controversy, shares credit with German mathematician Gottfried Wilhelm Leibniz for formulating calculus, infinitesimal calculus, though he developed calculus years before Leibniz. Newton contributed to and refined the scientific method, and his work is considered the most influential in bringing forth modern science. In the , Newton formulated the Newton's laws of motion, laws of motion and Newton's law of universal g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Big Bounce
The Big Bounce hypothesis is a cosmological model for the origin of the known universe. It was originally suggested as a phase of the ''cyclic model'' or ''oscillatory universe'' interpretation of the Big Bang, where the first cosmological event was the result of the collapse of a previous universe. It receded from serious consideration in the early 1980s after inflation theory emerged as a solution to the horizon problem, which had arisen from advances in observations revealing the large-scale structure of the universe. Inflation was found to be inevitably eternal, creating an infinity of different universes with typically different properties, suggesting that the properties of the observable universe are a matter of chance. An alternative concept that included a Big Bounce was conceived as a predictive and falsifiable possible solution to the horizon problem. Investigation continued as of 2022. Expansion and contraction The concept of the Big Bounce envisions the Big Ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nobel Prize In Physics
The Nobel Prize in Physics () is an annual award given by the Royal Swedish Academy of Sciences for those who have made the most outstanding contributions to mankind in the field of physics. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895 and awarded since 1901, the others being the Nobel Prize in Chemistry, Nobel Prize in Literature, Nobel Peace Prize, and Nobel Prize in Physiology or Medicine. Physics is traditionally the first award presented in the Nobel Prize ceremony. The prize consists of a medal along with a diploma and a certificate for the monetary award. The front side of the medal displays the same profile of Alfred Nobel depicted on the medals for Physics, Chemistry, and Literature. The first Nobel Prize in Physics was awarded to German physicist Wilhelm Röntgen in recognition of the extraordinary services he rendered by the discovery of X-rays. This award is administered by the Nobel Foundation and is widely regarded as the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmic Microwave Background
The cosmic microwave background (CMB, CMBR), or relic radiation, is microwave radiation that fills all space in the observable universe. With a standard optical telescope, the background space between stars and galaxies is almost completely dark. However, a sufficiently sensitive radio telescope detects a faint background glow that is almost isotropic, uniform and is not associated with any star, galaxy, or other astronomical object, object. This glow is strongest in the microwave region of the electromagnetic spectrum. The accidental Discovery of cosmic microwave background radiation, discovery of the CMB in 1965 by American radio astronomers Arno Allan Penzias and Robert Woodrow Wilson was the culmination of work initiated in the 1940s. The CMB is landmark evidence of the Big Bang scientific theory, theory for the origin of the universe. In the Big Bang cosmological models, during the earliest periods, the universe was filled with an Opacity (optics), opaque fog of dense, hot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Candle
The cosmic distance ladder (also known as the extragalactic distance scale) is the succession of methods by which astronomers determine the distances to celestial objects. A ''direct'' distance measurement of an astronomical object is possible only for those objects that are "close enough" (within about a thousand parsecs or 3e16 km) to Earth. The techniques for determining distances to more distant objects are all based on various measured correlations between methods that work at close distances and methods that work at larger distances. Several methods rely on a ''standard candle'', which is an astronomical object that has a known luminosity. The ladder analogy arises because no single technique can measure distances at all ranges encountered in astronomy. Instead, one method can be used to measure nearby distances, a second can be used to measure nearby to intermediate distances, and so on. Each rung of the ladder provides information that can be used to determine the distan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supernova
A supernova (: supernovae or supernovas) is a powerful and luminous explosion of a star. A supernova occurs during the last stellar evolution, evolutionary stages of a massive star, or when a white dwarf is triggered into runaway nuclear fusion. The original object, called the ''progenitor'', either collapses to a neutron star or black hole, or is completely destroyed to form a diffuse nebula. The peak optical luminosity of a supernova can be comparable to that of an entire galaxy before fading over several weeks or months. The last supernova directly observed in the Milky Way was Kepler's Supernova in 1604, appearing not long after Tycho's Supernova in 1572, both of which were visible to the naked eye. The supernova remnant, remnants of more recent supernovae have been found, and observations of supernovae in other galaxies suggest they occur in the Milky Way on average about three times every century. A supernova in the Milky Way would almost certainly be observable through mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
