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39-464: Heilig, who today would be thought of as a "multimedia" specialist, in the 1950s saw theater as an activity that could encompass all the senses in an effective manner, thus drawing the viewer into the onscreen activity. He dubbed it "Experience Theater", and detailed his vision of multi-sensory theater in a 1955 paper, "The Cinema of the Future" (Robinett 1994). In 1962 he built a prototype of his vision, dubbed

78-400: A mechanical flying dove. The sole mention of this from antiquity comes some five centuries after Archytas, when Aulus Gellius discusses a report by his mentor Favorinus : Archytas made a wooden model of a dove with such mechanical ingenuity and art that it flew; so nicely balanced was it, you see, with weights and moved by a current of air enclosed and hidden within it. About so improbable

117-481: A reputation for virtue as well as efficacy. The Seventh Letter , traditionally attributed to Plato , asserts that Archytas attempted to rescue Plato during his difficulties with Dionysius II of Syracuse . Some scholars have argued that Archytas may have served as one model for Plato's philosopher king , and that he influenced Plato's political philosophy as expressed in The Republic and other works. Archytas

156-493: A separate discipline in physics, formally treated as distinct from mechanics, whether it be classical fields or quantum fields . But in actual practice, subjects belonging to mechanics and fields are closely interwoven. Thus, for instance, forces that act on particles are frequently derived from fields ( electromagnetic or gravitational ), and particles generate fields by acting as sources. In fact, in quantum mechanics, particles themselves are fields, as described theoretically by

195-613: Is another tradition that goes back to the ancient Greeks where mathematics is used more extensively to analyze bodies statically or dynamically , an approach that may have been stimulated by prior work of the Pythagorean Archytas . Examples of this tradition include pseudo- Euclid ( On the Balance ), Archimedes ( On the Equilibrium of Planes , On Floating Bodies ), Hero ( Mechanica ), and Pappus ( Collection , Book VIII). In

234-413: Is said to be the first ancient Greek to have spoken of the sciences of arithmetic (logistic), geometry , astronomy , and harmonics as kin, which later became the medieval quadrivium . He is thought to have written a great number of works in the sciences, but only four fragments are generally believed to be authentic. According to Eutocius , Archytas was the first to solve the problem of doubling

273-483: Is the extensive use of mathematics in theories, as well as the decisive role played by experiment in generating and testing them. Quantum mechanics is of a bigger scope, as it encompasses classical mechanics as a sub-discipline which applies under certain restricted circumstances. According to the correspondence principle , there is no contradiction or conflict between the two subjects, each simply pertains to specific situations. The correspondence principle states that

312-447: Is treated in Euclid's Elements , where the construction for two proportional means can also be found. Archytas named the harmonic mean , important much later in projective geometry and number theory , though he did not discover it. He proved that supernummerary ratios cannot be divided by a mean proportional – an important result in ancient harmonics. Ptolemy considered Archytas

351-630: The kinetic energy of a free particle is E = ⁠ 1 / 2 ⁠ mv , whereas in relativistic mechanics, it is E = ( γ − 1) mc (where γ is the Lorentz factor ; this formula reduces to the Newtonian expression in the low energy limit). For high-energy processes, quantum mechanics must be adjusted to account for special relativity; this has led to the development of quantum field theory . Archytas Archytas ( / ˈ ɑːr k ɪ t ə s / ; Greek : Ἀρχύτας ; 435/410–360/350 BC )

390-474: The theory of impetus , which later developed into the modern theories of inertia , velocity , acceleration and momentum . This work and others was developed in 14th-century England by the Oxford Calculators such as Thomas Bradwardine , who studied and formulated various laws regarding falling bodies. The concept that the main properties of a body are uniformly accelerated motion (as of falling bodies)

429-492: The wave function . The following are described as forming classical mechanics: The following are categorized as being part of quantum mechanics: Historically, classical mechanics had been around for nearly a quarter millennium before quantum mechanics developed. Classical mechanics originated with Isaac Newton 's laws of motion in Philosophiæ Naturalis Principia Mathematica , developed over

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468-545: The 20th century based in part on earlier 19th-century ideas. The development in the modern continuum mechanics, particularly in the areas of elasticity, plasticity, fluid dynamics, electrodynamics, and thermodynamics of deformable media, started in the second half of the 20th century. The often-used term body needs to stand for a wide assortment of objects, including particles , projectiles , spacecraft , stars , parts of machinery , parts of solids , parts of fluids ( gases and liquids ), etc. Other distinctions between

507-508: The Middle Ages, Aristotle's theories were criticized and modified by a number of figures, beginning with John Philoponus in the 6th century. A central problem was that of projectile motion , which was discussed by Hipparchus and Philoponus. Persian Islamic polymath Ibn Sīnā published his theory of motion in The Book of Healing (1020). He said that an impetus is imparted to a projectile by

546-526: The Sensorama using a short film piece that detailed a bicycle ride through Brooklyn, created in the 1950s, and still seemed quite impressed by what it could do more than 40 years later. The Sensorama was able to display stereoscopic 3-D images in a wide-angle view, provide body tilting, supply stereo sound , and also had tracks for wind and aromas to be triggered during the film. Heilig was unable to obtain financial backing for his visions and patents , and so

585-659: The Sensorama work was halted. This technology-related article is a stub . You can help Misplaced Pages by expanding it . Mechanics Mechanics (from Ancient Greek μηχανική ( mēkhanikḗ )  'of machines ') is the area of physics concerned with the relationships between force , matter , and motion among physical objects . Forces applied to objects may result in displacements , which are changes of an object's position relative to its environment. Theoretical expositions of this branch of physics has its origins in Ancient Greece , for instance, in

624-418: The Sensorama, along with five short films for it to display. The Sensorama was a mechanical device, which includes a stereoscopic color display, fans, odor emitters, stereo‐sound system, and a motional chair. It simulated a motorcycle ride through New York and created the experience by having the spectator sit in an imaginary motorcycle while experiencing the street through the screen, fan-generated wind, and

663-556: The basis for satisfactory proofs, and developed the most famous argument for the infinity of the universe in antiquity. Archytas was born in Tarentum, a Greek city in the Italian Peninsula that was part of Magna Graecia , and was the son of Hestiaeus. He was presumably taught by Philolaus , and taught mathematics to Eudoxus of Cnidus and to Eudoxus' student, Menaechmus . Politically and militarily, Archytas appears to have been

702-455: The basis of Newtonian mechanics . There is some dispute over priority of various ideas: Newton's Principia is certainly the seminal work and has been tremendously influential, and many of the mathematics results therein could not have been stated earlier without the development of the calculus. However, many of the ideas, particularly as pertain to inertia and falling bodies, had been developed by prior scholars such as Christiaan Huygens and

741-426: The behavior of systems described by quantum theories reproduces classical physics in the limit of large quantum numbers , i.e. if quantum mechanics is applied to large systems (for e.g. a baseball), the result would almost be the same if classical mechanics had been applied. Quantum mechanics has superseded classical mechanics at the foundation level and is indispensable for the explanation and prediction of processes at

780-532: The cube (the so-called Delian problem ) with an ingenious geometric construction. Before this, Hippocrates of Chios had reduced this problem to the finding of two mean proportionals , equivalent to the extraction of cube roots . Archytas' demonstration uses lines generated by moving figures to construct the two proportionals between magnitudes and was, according to Diogenes Laërtius , the first in which mechanical motions entered geometry. The topic of proportions, which Archytas seems to have worked on extensively,

819-451: The distinction between quantum and classical mechanics, Albert Einstein 's general and special theories of relativity have expanded the scope of Newton and Galileo 's formulation of mechanics. The differences between relativistic and Newtonian mechanics become significant and even dominant as the velocity of a body approaches the speed of light . For instance, in Newtonian mechanics ,

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858-531: The dominant figure in Tarentum in his generation, somewhat comparable to Pericles in Athens a half-century earlier. The Tarentines elected him strategos ("general") seven years in a row, a step that required them to violate their own rule against successive appointments. Archytas was allegedly undefeated as a general in Tarentine campaigns against their southern Italian neighbors. In his public career, Archytas had

897-558: The ideas of other great thinkers of his time and began to calculate motion in terms of distance travelled from some starting position and the time that it took. He showed that the speed of falling objects increases steadily during the time of their fall. This acceleration is the same for heavy objects as for light ones, provided air friction (air resistance) is discounted. The English mathematician and physicist Isaac Newton improved this analysis by defining force and mass and relating these to acceleration. For objects traveling at speeds close to

936-447: The less-known medieval predecessors. Precise credit is at times difficult or contentious because scientific language and standards of proof changed, so whether medieval statements are equivalent to modern statements or sufficient proof, or instead similar to modern statements and hypotheses is often debatable. Two main modern developments in mechanics are general relativity of Einstein , and quantum mechanics , both developed in

975-451: The mayl is spent. He also claimed that a projectile in a vacuum would not stop unless it is acted upon, consistent with Newton's first law of motion. On the question of a body subject to a constant (uniform) force, the 12th-century Jewish-Arab scholar Hibat Allah Abu'l-Barakat al-Baghdaadi (born Nathanel, Iraqi, of Baghdad) stated that constant force imparts constant acceleration. According to Shlomo Pines , al-Baghdaadi's theory of motion

1014-468: The molecular, atomic, and sub-atomic level. However, for macroscopic processes classical mechanics is able to solve problems which are unmanageably difficult (mainly due to computational limits) in quantum mechanics and hence remains useful and well used. Modern descriptions of such behavior begin with a careful definition of such quantities as displacement (distance moved), time, velocity, acceleration, mass, and force. Until about 400 years ago, however, motion

1053-541: The most sophisticated Pythagorean music theorist, and scholars believe Archytas gave a mathematical account of the musical scales used by practicing musicians of his day. Later tradition regarded Archytas as the founder of mathematical mechanics . Vitruvius includes him in a list of twelve authors who wrote works on mechanics. T.N. Winter presents evidence that the pseudo-Aristotelian Mechanical Problems might have been authored by Archytas and later mis-attributed to Aristotle . Tradition also has it that Archytas built

1092-408: The motion of a spacecraft, regarding its orbit and attitude ( rotation ), is described by the relativistic theory of classical mechanics, while the analogous movements of an atomic nucleus are described by quantum mechanics. The following are the three main designations consisting of various subjects that are studied in mechanics. Note that there is also the " theory of fields " which constitutes

1131-426: The seventeenth century. Quantum mechanics developed later, over the nineteenth century, precipitated by Planck's postulate and Albert Einstein's explanation of the photoelectric effect . Both fields are commonly held to constitute the most certain knowledge that exists about physical nature. Classical mechanics has especially often been viewed as a model for other so-called exact sciences . Essential in this respect

1170-458: The simulated noise and smell of the city. These elements are triggered at the appropriate time, such as the release of exhaust chemicals when the rider approached a bus. The petrol fumes and the smell of pizza snack bars were recreated by chemicals. While the machine still functions today, audiences cannot interact with it and it cannot respond based on the user's actions. Howard Rheingold (in his 1991 book Virtual Reality ) spoke of his trial of

1209-427: The speed of light, Newton's laws were superseded by Albert Einstein 's theory of relativity . [A sentence illustrating the computational complication of Einstein's theory of relativity.] For atomic and subatomic particles, Newton's laws were superseded by quantum theory . For everyday phenomena, however, Newton's three laws of motion remain the cornerstone of dynamics, which is the study of what causes motion. Akin to

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1248-467: The speed of light. It can also be defined as the physical science that deals with the motion of and forces on bodies not in the quantum realm. The ancient Greek philosophers were among the first to propose that abstract principles govern nature. The main theory of mechanics in antiquity was Aristotelian mechanics , though an alternative theory is exposed in the pseudo-Aristotelian Mechanical Problems , often attributed to one of his successors. There

1287-435: The thrower, and viewed it as persistent, requiring external forces such as air resistance to dissipate it. Ibn Sina made distinction between 'force' and 'inclination' (called "mayl"), and argued that an object gained mayl when the object is in opposition to its natural motion. So he concluded that continuation of motion is attributed to the inclination that is transferred to the object, and that object will be in motion until

1326-541: The various sub-disciplines of mechanics concern the nature of the bodies being described. Particles are bodies with little (known) internal structure, treated as mathematical points in classical mechanics. Rigid bodies have size and shape, but retain a simplicity close to that of the particle, adding just a few so-called degrees of freedom , such as orientation in space. Otherwise, bodies may be semi-rigid, i.e. elastic , or non-rigid, i.e. fluid . These subjects have both classical and quantum divisions of study. For instance,

1365-469: The writings of Aristotle and Archimedes (see History of classical mechanics and Timeline of classical mechanics ). During the early modern period , scientists such as Galileo Galilei , Johannes Kepler , Christiaan Huygens , and Isaac Newton laid the foundation for what is now known as classical mechanics . As a branch of classical physics , mechanics deals with bodies that are either at rest or are moving with velocities significantly less than

1404-415: Was "the oldest negation of Aristotle 's fundamental dynamic law [namely, that a constant force produces a uniform motion], [and is thus an] anticipation in a vague fashion of the fundamental law of classical mechanics [namely, that a force applied continuously produces acceleration]." Influenced by earlier writers such as Ibn Sina and al-Baghdaadi, the 14th-century French priest Jean Buridan developed

1443-524: Was an Ancient Greek mathematician , music theorist , statesman, and strategist from the ancient city of Taras (Tarentum) in Southern Italy . He was a scientist and philosopher affiliated with the Pythagorean school and famous for being the reputed founder of mathematical mechanics and a friend of Plato . As a Pythagorean, Archytas believed that arithmetic (logistic), rather than geometry, provided

1482-578: Was explained from a very different point of view. For example, following the ideas of Greek philosopher and scientist Aristotle, scientists reasoned that a cannonball falls down because its natural position is in the Earth; the Sun, the Moon, and the stars travel in circles around the Earth because it is the nature of heavenly objects to travel in perfect circles. Often cited as father to modern science, Galileo brought together

1521-439: Was worked out by the 14th-century Oxford Calculators . Two central figures in the early modern age are Galileo Galilei and Isaac Newton . Galileo's final statement of his mechanics, particularly of falling bodies, is his Two New Sciences (1638). Newton's 1687 Philosophiæ Naturalis Principia Mathematica provided a detailed mathematical account of mechanics, using the newly developed mathematics of calculus and providing

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