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Title: RETHINKING RELATIVITY
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http://www.gravitywarpdrive.com/Rethinking_Relativity.htm
URL Source: http://www.gravitywarpdrive.com/Rethinking_Relativity.htm
Published: Oct 13, 2007
Author: TOM BETHEL
Post Date: 2007-10-13 17:52:19 by RickyJ
Keywords: None
Views: 505
Comments: 15
Any physicists here at 4um care to comment on this? I would like your thoughts on this article. No one has paid attention yet, but a well-respected physics journal just published an article whose conclusion, if generally accepted, will undermine the foundations of modern physics -- Einstein’s Theory of Relativity in particular. Published in Physics Letters A (December 21, 1998), the article claims that the speed with which the force of gravity propagates must be at least twenty billion times faster than the speed of light. This would contradict the Special Theory of Relativity of 1905, which asserts that nothing can go faster than light. This claim about the special status of the speed of light has become part of the world view of educated laymen in the twentieth century. NOTE: Tom Van Flandern’s article, titled “The Speed of Gravity - What the Experiments Say,” is provided as a Web Page on this Website. Special Relativity, as opposed to the General Theory (1916), is considered by experts to be above criticism, because it has been confirmed “over and over again.” But several dissident physicists believe that there is a simpler way of looking at the facts, a way that avoids the mind-bending complications of Relativity. Their arguments can be understood by laymen. I wrote about one of these dissidents, Peter Beckmann, over five years ago (TAS, August 1993, and Correspondence, TAS, October 1993). The present article introduces new people and arguments. The subject is important because if Special Relativity is supplanted, much of twentieth-century physics, including quantum theory, will have to be reconsidered in that light. The article in Physics Letters A was written by Tom Van Flandern, a research associate in the physics department at the University of Maryland. He also publishes Meta Research Bulletin which supports “promising but unpopular alternative ideas in astronomy.” In the 1990’s, he worked as a special consultant to the Global Positioning System (GPS), a set of satellites whose atomic clocks allow ground observers to determine their position to within about a foot. Van Flandern reports that an intriguing controversy arose before GPS was even launched. Special Relativity gave Einsteinians reason to doubt whether it would work at all. In fact, it works fine (But more on that later). The publication of his article is a breakthrough of sorts. For years, most editors of mainstream physics journals have automatically rejected articles arguing against Special Relativity. This policy was informally adopted in the wake of the Herbert Dingle controversy. A professor of science at the University of London, Dingle had written a book popularizing Special Relativity, but by the 1960’s he had become convinced that it couldn’t be true. So he wrote another book, Science at the Crossroads (1972), contradicting the first. Scientific journals, especially Nature, were bombarded with his (and others’) letters. An editor of Physics Letters A promised Van Flandern that reviewers would not be allowed to reject his article simply because it conflicted with received wisdom. Van Flandern begins with the “most amazing thing” he learned as a graduate student of celestial mechanics at Yale: that all gravitational interactions must be taken as instantaneous. At the same time, students were also taught that Einstein’s Special Relativity proved that nothing could propagate faster than light in a vacuum. The disagreement “sat there like an irritant,” Van Flandern told me. He determined that one day he would find its resolution. Today, he thinks that a new interpretation of Relativity may be needed. The argument that gravity must travel faster than light goes like this. If its speed limit is that of light, there must be an appreciable delay in its action. By the time the Sun’s “pull” reaches us, the Earth will have “moved on” for another 8.3 minutes (the time of light travel). But by then the Sun’s pull on the Earth will not be in the same straight line as the Earth’s pull on the Sun. The effect of these misaligned forces “would be to double the Earth’s distance from the Sun in 1200 years.” Obviously, this is not happening. The stability of planetary orbits tells us that gravity must propagate much faster than light. Accepting this reasoning, Isaac Newton assumed that the force of gravity must be instantaneous. Astronomical data support this conclusion. We know, for example, that the Earth accelerates toward a point 20 arc-seconds in front of the visible Sun -- that is, toward the true, instantaneous direction of the Sun. Its light comes to us from one direction, its “pull” from a slightly different direction. This implies different propagation speeds for light and gravity. It might seem strange that something so fundamental to our understanding of physics can still be a matter of debate. But that in itself should encourage us to wonder how much we really know about the physical world. In certain Internet discussion groups, “the most frequently asked question and debated topic is ‘What is the speed of gravity?,’” Van Flandern writes. It is heard less often in the classroom, but only “because many teachers and most textbooks head off the question.” They understand the argument that it must go very fast indeed, but they also have been trained not to let anything exceed Einstein’s speed limit. So maybe there is something wrong with Special Relativity after all. In The ABC of Relativity (1925), Bertrand Russell said that just as the Copernican system once seemed impossible and now seems obvious, so, one day, Einstein’s Relativity theory “will seem easy.” But it remains as “difficult” as ever, not because the math is easy or difficult (Special Relativity requires only high-school math, General Relativity really is difficult), but because elementary logic must be abandoned. “Easy Einstein” books remain baffling to almost all. The sun-centered solar system, on the other hand, has all along been easy to grasp. Nonetheless, Special Relativity (which deals with motion in a straight line) is thought to be beyond reproach. General Relativity (which deals with gravity, and accelerated motion in general) is not regarded with the same awe. Stanford’s Francis Everitt, the director of an experimental test of General Relativity due for space-launch next year, has summarized the standing of the two theories in this way: “I would not be at all surprised if Einstein’s General Theory of Relativity were to break down,” he wrote. “Einstein himself recognized some serious shortcomings in it, and we know on general grounds that it is very difficult to reconcile with other parts of modern physics. With regard to Special Relativity, on the other hand, I would be much more surprised. The experimental foundations do seem to be much more compelling.” This is the consensus view. Dissent from Special Relativity is small and scattered. But it is there, and it is growing. Van Flandern’s article is only the latest manifestation. In 1987, Peter Beckmann, who taught at the University of Colorado, published Einstein Plus Two, pointing out that the observations that led to Relativity can be more simply reinterpreted in a way that preserves universal time. The journal he founded, Galilean Electrodynamics was taken over by Howard Hayden of the University of Connecticut (Physics), and is now edited by Cynthia Kolb Whitney of the Electro-Optics Technology Center at Tufts. Hayden held colloquia on Beckmann’s ideas at several New England universities, but could find no physicist who even tried to put up an argument. A brief note on Einstein’s most famous contribution to physics -- the formula that everyone knows. When they hear that heresy is in the air, some people come to the defense of Relativity with this question: “Atom bombs work, don’t they?” They reason as follows: The equation E = mc2 was discovered as a byproduct of Einstein’s Special Theory of Relativity (True). Relativity, they conclude, is indispensable to our understanding of the way the world works. But that does not follow. Alternative derivations of the famous equation dispense with Relativity. One such was provided by Einstein himself in 1946. And it is simpler than the relativistic rigmarole. But few Einstein books or biographies mention the alternative. They admire complexity, and cling to it. Consider Clifford M. Will of Washington University, a leading proponent of Relativity today. “It is difficult to imagine life without Special Relativity,” he says in Was Einstein Right? “Just think of all the phenomena or features of our world in which Special Relativity plays a role. Atomic energy, both the explosive and the controlled kind. The famous equation E = mc2 tells how mass can be converted into extraordinary amounts of energy.” Note the misleading predicate, “plays a role.” He knows that the stronger claim, “is indispensable,” would be pounced on as inaccurate. Is there an alternative way of looking at all the facts that supposedly would be orphaned without Relativity? Is there a simpler way? A criterion of simplicity has frequently been used as a court of appeal in deciding between theories. If it is made complex enough, the Ptolemaic system can predict planetary positions correctly. But the Sun-centered system is much simpler, and ultimately we prefer it for that reason. Tom Van Flandern says the problem is that the Einstein experts who have grown accustomed to “Minkowski diagrams and real relativistic thinking” find the alternative of universal time and “Galilean space” actually more puzzling than their own mathematical ingenuities. Once relativists have been thoroughly trained, he says, it’s as difficult for them to rethink the subject in classical terms as it is for laymen to grasp time dilation and space contraction. For laymen, however, and for those physicists who have not specialized in Relativity, which is to say the vast majority of physicists, there’s no doubt that the Galilean way is far simpler than the Einsteinian. Special Relativity was first proposed as a way of sidestepping the great difficulty that arose in physics as a result of the Michelson-Morley experiment (1887). Clerk Maxwell had shown that light and radio waves share the same electromagnetic spectrum, differing only in wave length. Sea waves require water, sound waves air, so, it was argued, electromagnetic waves must have their own medium to travel in. It was called the ether. “There can be no doubt that the interplanetary and interstellar spaces are not empty,” Maxwell wrote, “but are occupied by a material substance or body, which is certainly the largest, and probably the most uniform body of which we have any knowledge.” As today’s dissidents see things, it was Maxwell’s assumption of uniformity that was misleading. The experiment of Michelson and Morley tried to detect this ether. Since the Earth in its orbital motion must plow through it, an “ether wind” should be detectable, just as a breeze can be felt outside the window of a moving car. Despite repeated attempts, however, no ethereal breeze could be felt. A pattern of interference fringes was supposed to shift when Michelson’s instrument was rotated. But there was no fringe shift. Einstein explained this result in radical fashion. There is no need of an ether, he said. And there was no fringe shift because the speed of an approaching light wave is unaffected by the observer’s motion. But if the speed of light always remains the same, time itself would have to slow down, and space contract to just the amount needed to ensure that the one divided by the other -- space divided by time -- always gave the same value: the unvarying speed of light. The formula that achieved this result was quite simple, and mathematically everything worked out nicely and agreed with observation. The skeptical, meanwhile, were placated with this formula: “I know it seems odd that time slows down and space contracts when things move, but don’t worry, a measurable effect only occurs at high velocities -- much higher than anything we find in everyday life. So for all practical purposes we can go on thinking in the same old way.” (Meanwhile, space and time have been subordinated to velocity. Get used to it.) Now we come to some modern experimental findings. Today we have very accurate clocks, accurate to a billionth of a second a day. The tiny differentials predicted by Einstein are now measurable. And the interesting thing is this: Experiments have shown that atomic clocks really do slow down when they move, and atomic particles really do live longer. Does this mean that time itself slows down? Or is there a simpler explanation? The dissident physicists I have mentioned disagree about various things, but they are beginning to unite behind this proposition: There really is an ether, in which electromagnetic waves travel, but it is not the all-encompassing, uniform ether proposed by Maxwell. Instead, it corresponds to the gravitational field that all celestial bodies carry about with them. Close to the surface (of sun, planet, or star) the field, or ether, is relatively more dense. As you move out into space it becomes more attenuated. Beckmann’s Einstein Plus Two introduces this hypothesis, I believe for the first time, and he told me it was first suggested to him in the 1950’s by one of his graduate students, Jiri Pokorny, at the Institute of Radio Engineering and Electronics in Prague. Pokorny later joined the department of physics at Prague’s Charles University, and today is retired. I believe that all the facts that seem to require special or General Relativity can be more simply explained by assuming an ether that corresponds to the local gravitational field. Michelson found no “ether wind,” or fringe shift, because of course the Earth’s gravitational field moves forward with the Earth. As for the bending of starlight near the Sun, the confirmation of General Relativity that made Einstein world-famous, it is easily explained given a non-uniform light medium. It is a well known law of physics that wave fronts do change direction when they enter a denser medium. According to Howard Hayden, refracted starlight can be derived this way “with a few lines of high school algebra.?” And derived exactly. The tensor calculus and Riemannian geometry of General Relativity gives only an approximation. Likewise the “Shapiro Time-Delay,” observed when radar beams pass close to the Sun and bounce back from Mercury. Some may prefer to try to understand all this in terms of the “curvature of Space-Time,” to use the Einstein formulation (unintelligible to laymen, I believe). But they should know that a far simpler alternative exists. The advance of the perihelion of Mercury’s orbit, another famous confirmation of General Relativity, is worth a closer look (the perihelion is the point in the orbit closest to a sun). Graduate theses may one day be written about this peculiar episode in the history of science. In his book, Subtle Is the Lord, Abraham Pais reports that when Einstein saw that his calculations agreed with Mercury’s orbit, “he had the feeling that something actually snapped in him ... This experience was, I believe, by far the strongest emotional experience in Einstein’s scientific life, perhaps in all his life. Nature had spoken to him.” Fact: The equation that accounted for Mercury’s orbit had been published 17 years earlier, before Relativity was invented. The author, Paul Gerber, used the assumption that gravity is not instantaneous, but propagates with the speed of light. After Einstein published his General Relativity derivation, arriving at the same equation, Gerber’s article was reprinted in *Annalen der Physik* (the journal that had published Einstein’s Relativity papers). The editors felt that Einstein should have acknowledged Gerber’s priority. Although Einstein said he had been in the dark, it was pointed out that Gerber’s formula had been published in Mach’s Science of Mechanics, a book that Einstein was known to have studied. So how did they both arrive at the same formula? Tom Van Flandern was convinced that Gerber’s assumption (gravity propagates with the speed of light) was wrong. So he studied the question. He points out that the formula in question is well known in celestial mechanics. Consequently, it could be used as a “target” for calculations that were intended to arrive at it. He saw that Gerber’s method “made no sense, in terms of the principles of celestial mechanics.” Einstein had also said (in a 1920 newspaper article) that Gerber’s derivation was “wrong through and through.” So how did Einstein get the same formula? Van Flandern went through his calculations, and found to his amazement that they had “three separate contributions to the perihelion; two of which add, and one of which cancels part of the other two; and you wind up with just the right multiplier.” So he asked a colleague at the University of Maryland, who as a young man had overlapped with Einstein at Princeton’s Institute for Advanced Study, how in his opinion Einstein had arrived at the correct multiplier. This man said it was his impression that, “knowing the answer,” Einstein had “jiggered the arguments until they came out with the right value.” If the General Relativity method is correct, it ought to apply everywhere, not just in the solar system. But Van Flandern points to a conflict outside it: binary stars with highly unequal masses. Their orbits behave in ways that the Einstein formula did not predict. “Physicists know about it and shrug their shoulders,” Van Flandern says. They say there must be “something peculiar about these stars, such as an oblateness, or tidal effects.” Another possibility is that Einstein saw to it that he got the result needed to “explain” Mercury’s orbit, but that it doesn’t apply elsewhere. The simplest way to understand all this “without going crazy,” Van Flandern says, is to discard Einsteinian Relativity and to assume that “there is a light-carrying medium.” When a clock moves through this medium “it takes longer for each electron in the atomic clock to complete its orbit.” Therefore, it makes fewer “ticks” in a given time than a stationary clock. Moving clocks slow down, in short, because they are “ploughing through this medium and working more slowly.” It’s not time that slows down. It’s the clocks. All the experiments that supposedly “confirm” Special Relativity do so because all have been conducted in laboratories on the Earth’s surface, where every single moving particle, or moving atomic clock, is in fact “ploughing through” the Earth’s gravitational field, and therefore slowing down. Both theories, Einsteinian and local field, would yield the same results. So far. Now let’s turn back to the Global Positioning System. At high altitude, where the GPS clocks orbit the Earth, it is known that the clocks run roughly 46,000 nanoseconds (one-billionth of a second) a day faster than at ground level, because the gravitational field is thinner 20,000 kilometers above the Earth. The orbiting clocks also pass through that field at a rate of three kilometers per second -- their orbital speed. For that reason, they tick 7,000 nanoseconds a day slower than stationary clocks. To offset these two effects, the GPS engineers reset the clock rates, slowing them down before launch by 39,000 nanoseconds a day. They then proceed to tick in orbit at the same rate as ground clocks, and the system "works." Ground observers can indeed pin-point their position to a high degree of precision. In (Einstein) theory, however, it was expected that because the orbiting clocks all move rapidly and with varying speeds relative to any ground observer (who may be anywhere on the Earth’s surface), and since in Einstein’s theory the relevant speed is always speed relative to the observer, it was expected that continuously varying relativistic corrections would have to be made to clock rates. This in turn would have introduced an unworkable complexity into the GPS. But these corrections were not made. Yet “the system manages to work, even though they use no relativistic corrections after launch,” Van Flandern said. “They have basically blown off Einstein.” The latest findings are not in agreement with relativistic expectations. To accommodate these findings, Einsteinians are proving adept at arguing that if you look at things from a different “reference frame,” everything still works out fine. But they have to do the equivalent of standing on their heads, and it’s not convincing. A simpler theory that accounts for all the facts will sooner or later supplant one that looks increasingly Rube Goldberg-like. I believe that is now beginning to happen. Dingle’s Question: University of London Professor Herbert Dingle showed why Special Relativity will always conflict with logic, no matter when we first learn it. According to the theory, if two observers are equipped with clocks, and one moves in relation to the other, the moving clock runs slower than the non-moving clock. But the Relativity principle itself (an integral part of the theory) makes the claim that if one thing is moving in a straight line in relation to another, either one is entitled to be regarded as moving. It follows that if there are two clocks, A and B, and one of them is moved, clock A runs slower than B, and clock B runs slower than A. Which is absurd. Dingle’s Question was this: Which clock runs slow? Physicists could not agree on an answer. As the debate raged on, a Canadian physicist wrote to Nature in July 1973: “Maybe the time has come for all of those who want to answer to get together and to come up with one official answer. Otherwise the plain man, when he hears of this matter, may exercise his right to remark that when the experts disagree they cannot all be right, but they can all be wrong.” The problem has not gone away. Alan Lightman of MIT offers an unsatisfactory solution in his Great Ideas in Physics (1992). “The fact that each observer sees the other clock ticking more slowly than his own clock does not lead to a contradiction. A contradiction could arise only if the two clocks could be put back together side by side at two different times.” But clocks in constant relative motion in a straight line “can be brought together only once, at the moment they pass.” So the theory is protected from its own internal logic by the impossibility of putting it to a test. Can such a theory be said to be scientific? --TB Tom Van Flandern’s Meta Research Bulletin ($15) and his book, Dark Matter, Missing Planets ($24.50), may be obtained from P.O. Box 15186, Chevy Chase, MD 20825; Peter Beckmann’s Einstein Plus Two ($40) from Golem Press, P.O. Box 1342, Boulder, CO 80306. Beckmann’s book is highly technical; Van Flandern’s is mostly accessible to laymen. Tom Bethell is TAS’s Washington correspondent. His new book, The Noblest Triumph, was recently published by St. Martin’s Press.
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#1. To: RickyJ (#0)
See Wikipedia's article on the subject: Speed of gravity
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#2. To: RickyJ (#0)
Tom van Flandern used to be a guest on the old Art Bell radio show. He is good at finding wholes in modern science but he has not come up with an ultimate explanation for time, space and gravity. I would like to point out that E equals MC squared was discovered by an Italian engineer named De Pretto who published it a year before Einstein did. Friends of Einstein forwarded a translation of the article from Italian to him in Switzerland.
The Truth of 911 Shall Set You Free From The Lie
#3. To: Horse (#2)
Breast From Wikipedia, the free encyclopedia • Ten things you may not know about images on Wikipedia • Jump to: navigation, search For other uses, see Breast (disambiguation). For various cities in Europe pronounced in a similar way, see Brest. “Boobs” redirects here. For other uses, see boob. Pregnant human female's breast Pregnant human female's breast The term breast refers to the upper ventral region of an animal’s torso, particularly that of mammals, including human beings. The breasts of a female mammal’s body contain the mammary glands, which secrete milk used to feed infants. This article deals with the human breast; for other animals, see udder and mammary gland. Breasts are more visible on adult women, but male humans also have breasts which, although usually less prominent, are structurally identical (homologous) to the female, as they develop embryologically from the same tissues. Look up breasts, WikiSaurus:breasts in Wiktionary, the free dictionary. Contents [hide] * 1 Anatomy o 1.1 Lymphatic drainage o 1.2 Shape and support o 1.3 Development o 1.4 Changes * 2 Function o 2.1 Breastfeeding o 2.2 Sexual role o 2.3 Other suggested functions * 3 Cultural status o 3.1 In art, religion, and legend o 3.2 In practice o 3.3 Clothing o 3.4 Plastic surgery * 4 Disorders o 4.1 Infections and inflammations o 4.2 Benign conditions o 4.3 Pre-malignant diseases o 4.4 Malignant diseases * 5 See also * 6 References * 7 Documentary film * 8 External links Anatomy See also: Human anatomy Breast schematic diagram (adult female human cross section) - Legend: 1. Chest wall 2. Pectoralis muscles 3. Lobules 4. Nipple 5. Areola 6. Duct 7. Fatty tissue 8. Skin Breast schematic diagram (adult female human cross section) - Legend: 1. Chest wall 2. Pectoralis muscles 3. Lobules 4. Nipple 5. Areola 6. Duct 7. Fatty tissue 8. Skin The breasts are modified sudoriferous (sweat) glands, producing milk in females.[1] Each breast has one nipple surrounded by the areola. The areola is colored from pink to dark brown and has several sebaceous glands. In females, the larger mammary glands within the breast produce the milk. They are distributed throughout the breast, with two-thirds of the tissue found within 30 mm of the base of the nipple.[2] These are drained to the nipple by between 4 and 18 lactiferous ducts, where each duct has its own opening. The network formed by these ducts is complex, like the tangled roots of a tree. It is not always arranged radially, and branches close to the nipple. The ducts near the nipple do not act as milk reservoirs; Ramsay et al. have shown that conventionally described lactiferous sinuses do not, in fact, exist. The remainder of the breast is composed of connective tissue (collagen and elastin), adipose tissue (fat), and Cooper's ligaments. The ratio of glands to adipose tissues rises from 1:1 in nonlactating women to 2:1 in lactating women.[2] The breasts sit over the pectoralis major muscle and usually extend from the level of the 2nd rib to the level of the 6th rib anteriorly. The superior lateral quadrant of the breast extends diagonally upwards towards the axillae and is known as the tail of Spence. A thin layer of mammary tissue extends from the clavicle above to the seventh or eighth ribs below and from the midline to the edge of the latissimus dorsi posteriorly. (For further explanation, see anatomical terms of location.) The arterial blood blood supply to the breasts is derived from the internal thoracic artery (formerly called the internal mammary artery), lateral thoracic artery, thoracoacromial artery, and posterior intercostal arteries. The venous drainage of the breast is mainly to the axillary vein, but there is some drainage to the internal thoracic vein and the intercostal veins. Both sexes have a large concentration of blood vessels and nerves in their nipples. The nipples of both females and males can become erect in response to sexual stimuli,[3] and also to cold. The breast is innervated by the anterior and lateral cutaneous branches of the fourth through sixth intercostal nerves. The nipple is supplied by the T4 dermatome. Lymphatic drainage About 75% of lymph from the breast travels to the ipsilateral axillary lymph nodes. The rest travels to parasternal nodes, to the other breast, or abdominal lymph nodes. The axillary nodes include the pectoral, subscapular, and humeral groups of lymph nodes. These drain to the central axillary lymph nodes, then to the apical axillary lymph nodes. The lymphatic drainage of the breasts is particularly relevant to oncology, since breast cancer is a common cancer and cancer cells can break away from a tumour and spread to other parts of the body through the lymph system by metastasis. Shape and support Relatively round breasts which protrude almost horizontally. Relatively round breasts which protrude almost horizontally. Breasts vary in both size and shape, and their external appearance is not predictive of their internal anatomy or lactation potential. The shape of a woman’s breasts is in large part dependent on their support, which primarily comes from the Cooper's ligaments, and the underlying chest on which they rest. The breast is attached at its base to the chest wall by the deep fascia over the pectoral muscles. On its upper surface it is given some support by the covering skin where it continues on to the upper chest wall. It is this support which determines the shape of the breasts. In a small fraction of women, the frontal milk sinuses (ampulla) in the breasts are not flush with the surrounding breast tissue, which causes the sinus area to visibly bulge outward. In discussing the support of breasts, it is helpful to draw a distinction between breasts which rest on the chest below, and those which do not. High, rounded breasts protrude almost horizontally from the chest wall. All breasts are like this in early stages of development, and such a shape is common in younger women and girls. This protruding or “high” breast is anchored to the chest at its base, and the weight is distributed evenly over the area of the base of the approximately dome- or cone-shaped breasts. [citation needed] In the “low” breast, a proportion of the breasts’ weight is actually supported by the chest against which the lower breast surface comes to rest, as well as the deep anchorage at the base. The weight is thus distributed over a larger area, which has the effect of reducing the strain. In both males and females, the thoracic cavity slopes progressively outwards from the thoracic inlet (at the top of the breastbone) above to the lowest ribs which mark its lower boundary, allowing it to support the breasts. The inframammary fold (or line, or crease) is an anatomic structure created by adherence between elements in the skin and underlying connective tissue[4] and represents the inferior extent of breast anatomy. Some teenagers may develop breasts whose skin comes into contact with the chest below the fold at an early age, and some women may never develop such breasts; both situations are perfectly normal. The relationship of the nipple position to the fold is described as ptosis, a term also applied to other body parts and which refers in general to drooping or sagging. Due to breast weight and relaxation of support structures, the nipple-areola complex and breast tissue may eventually hang below the fold, and in some cases the breasts may extend as far as, or even beyond, the navel. The length from the nipple to the sternal notch (central, upper border) in the youthful breast averages 21 cm and is a common anthropometric figure used to assess both breast symmetry and ptosis. Lengthening of both this measurement and the distance between the nipple and the fold are both characteristic of advancing grades of ptosis. The end of the breast, which includes the nipple, may either be flat (a 180 degree angle) or angled (angles lower than 180 degrees). Breast ends are rarely angled sharper than 60 degrees. Angling of the end of the breast is caused in part by the ligaments that suspend it, such that the breast ends often have a more obtuse angle when a woman is lying on her back. Breasts exist in a range of ratios between length and base diameter, usually ranging from 1/2 to 1. Development Main article: Thelarche The development of a girl's breasts during puberty is triggered by sex hormones, chiefly estrogen. This hormone has been demonstrated to cause the development of woman-like, enlarged breasts in men, a condition called gynecomastia, and is sometimes used deliberately for this effect in male-to-female sex change hormone replacement therapy. In most cases, the breasts fold down over the chest wall during Tanner stage development, as shown in this diagram.[5] It is typical for a woman’s breasts to be unequal in size particularly while the breasts are developing. Statistically it is slightly more common for the left breast to be the larger.[6] In rare cases, the breasts may be significantly different in size, or one breast may fail to develop entirely. A large number of medical conditions are known to cause abnormal development of the breasts during puberty. Virginal breast hypertrophy is a condition which involves excessive growth of the breasts, and in some cases the continued growth beyond the usual pubescent age. Breast hypoplasia is a condition where one or both breasts fail to develop. In Cameroon, some girls are subjected to breast ironing to stunt breast growth in order to make them less sexually attractive in the belief that this makes them less likely to become a victim of rape. Changes Breast with visible stretchmarks. Breast with visible stretchmarks. As breasts are mostly composed of adipose tissue, their size can change over time. This occurs for a number of reasons, most obviously when a girl grows during puberty and when a woman becomes pregnant. The breast size may also change if she gains (or loses) weight for any other reason. Any rapid increase in size of the breasts can result in the appearance of stretchmarks. It is typical for a number of other changes to occur during pregnancy: in addition to becoming larger, the breasts generally become firmer, mainly due to hypertrophy of the mammary gland in response to the hormone prolactin. The size of the nipples may increase noticeably and their pigmentation may become darker. These changes may continue during breastfeeding. The breasts generally revert to approximately their previous size after pregnancy, although there may be some increased sagging and stretchmarks. The size of a woman’s breasts usually fluctuates during the menstrual cycle, particularly with premenstrual water retention. An increase in breast size is a common side effect of use of the combined oral contraceptive pill. The breasts naturally sag through aging, as the ligaments become elongated. Function Breastfeeding Main article: Breastfeeding The breasts of a woman who is six months pregnant. The breasts of a woman who is six months pregnant.[7] The primary function of mammary glands is to nurture young by producing breast milk. The production of milk is called lactation. (While the mammary glands that produce milk are present in the male, they normally remain undeveloped.) The orb-like shape of breasts may help limit heat loss, as a fairly high temperature is required for the production of milk. Alternatively, one theory states that the shape of the human breast evolved in order to prevent infants from suffocating while feeding.[8] Since human infants do not have a protruding jaw like human evolutionary ancestors and other primates, the infant’s nose might be blocked by a flat female chest while feeding.[8] According to this theory, as the human jaw receded, the breasts became larger to compensate.[8] Milk production unrelated to pregnancy can also occur. This galactorrhea may be an adverse effect of some medicinal drugs (such as some antipsychotic medication), extreme physical stress or endocrine disorders. If it occurs in men it is called male lactation. Newborn babies are often capable of lactation because they receive the hormones prolactin and oxytocin via the mother's bloodstream, filtered through the placenta. This neonatal liquid is known colloquially as witch's milk. Sexual role Breasts play an important part in human sexual behavior. They are one of most visible or obvious female secondary sex characteristics,[9] and play an important role in sexual attraction of partners, and pleasure of the individual. On sexual arousal breast size increases, venous patterns across the breasts become more visible, and nipples harden. During sexual intercourse it is common practice to press or massage breasts with hands. Oral stimulation of nipples and breasts is also common. Some women can achieve breast orgasms. In the ancient Indian work the Kama Sutra, marking breasts with nails and biting with teeth are explained as erotic[10]. Other suggested functions This section does not cite any references or sources. Please improve this section by adding citations to reliable sources. Unverifiable material may be challenged and removed. (tagged since September 2007) Zoologists point out that no female mammal other than the human has breasts of comparable size, relative to the rest of the body, when not lactating and that humans are the only primate that has permanently swollen breasts. This suggests that the external form of the breasts is connected to factors other than lactation alone. One theory is based around the fact that, unlike nearly all other primates, human females do not display clear, physical signs of ovulation. This could have plausibly resulted in human males evolving to respond to more subtle signs of ovulation. During ovulation, the increased estrogen present in the female body results in a slight swelling of the breasts, which then males could have evolved to find attractive. In response, there would be evolutionary pressures that would favor females with more swollen breasts who would, in a manner of speaking, appear to males to be the most likely to be ovulating. Some zoologists (notably Desmond Morris) believe that the shape of female breasts evolved as a frontal counterpart to that of the buttocks, the reason being that whilst other primates mate in the rear-entry position, humans are more likely to successfully copulate by mating face to face, the so-called missionary position. A secondary sexual characteristic on a woman’s chest would have encouraged this in more primitive incarnations of the human race, and a face on encounter may have helped found a relationship between partners beyond merely a sexual one.[11] Cultural status In art, religion, and legend Edouard Manet, “Blonde Woman With Bare Breasts” Edouard Manet, “Blonde Woman With Bare Breasts” Historically, breasts have been regarded as fertility symbols, because they are the source of life-giving milk. Certain prehistoric female statuettes—so-called Venus figurines—often emphasised the breasts, as in the example of the Venus of Willendorf. In historic times, goddesses such as Ishtar were shown with many breasts, alluding to their role as protectors of childbirth and mothering. The legendary tribe of Amazons bared their breasts, and in some accounts removed one breast to allow better combat and archery. Some religions afford the breast a special status, either in formal teachings or in symbolism. Islam forbids public exposure of the female breasts.[12] In Christian iconography, some works of art depict women with their breasts in their hands or on a platter, signifying that they died as a martyr by having their breasts severed; one example of this is Saint Agatha of Sicily. In Silappatikaram, Kannagi tears off her left breast and flings it on Madurai, cursing it, causing a devastating fire. In practice Breasts are secondary sex characteristics and sexually sensitive. Bare female breasts can elicit heightened sexual desires from men and women. Cultures that associate the breast primarily with sex (as opposed to with breastfeeding) tend to designate bare breasts as indecent, and they are not commonly displayed in public, in contrast to male chests. Other cultures view female toplessness as acceptable, and in some countries women have never been forbidden to bare their chests; in some African cultures, for example, the thigh is highly sexualised and never exposed in public, but the breast is not taboo. Opinion on the exposure of breasts is often dependent on the place and context, and in some Western societies exposure of breasts on a beach may be acceptable, although in town centres, for example, it is usually indecent. In some areas, the prohibition against the display of a woman’s breasts generally only restricts exposure of the nipples. Women in some areas and cultures are approaching the issue of breast exposure as one of sexual equality, since men (and pre-pubescent children) may bare their chests, but women and teenage girls are forbidden. In the United States, the topfree equality movement seeks to redress this imbalance. This movement won a decision in 1992 in the New York State Court of Appeals—“People v. Santorelli”, where the court ruled that the state’s indecent exposure laws do not ban women from being barebreasted. A similar movement succeeded in most parts of Canada in the 1990s. In Australia and much of Europe it is acceptable for women and teenage girls to sunbathe topless on some public beaches and swimming pools, but these are generally the only public areas where exposing breasts is acceptable. When breastfeeding a baby in public, legal and social rules regarding indecent exposure and dress codes, as well as inhibitions of the woman, tend to be relaxed. Numerous laws around the world have made public breastfeeding legal and disallow companies from prohibiting it in the workplace. Yet the public reaction at the sight of breastfeeding can make the situation uncomfortable for those involved. See also modesty, nudism and exhibitionism. Clothing Since the breasts are flexible, their shape may be affected by clothing, and foundation garments in particular. A brassiere (bra) may be worn to give additional support and to alter the shape of the breasts. There is some debate over whether such support is desirable. A long term clinical study showed that women with large breasts can suffer shoulder pain as a result of bra straps,[13] although a well fitting bra should support most of the breasts’ weight with proper sized cups and back band rather than on the shoulders. Plastic surgery Plastic surgical procedures of the breast include those for both cosmetic and reconstructive surgery indications. Some women choose these procedures as a result of the high value placed on symmetry of the human form, and because they identify their femininity and sense of self with their breasts. After mastectomy (the surgical removal of a breast, usually to treat breast cancer) some women undergo breast reconstruction, either with breast implants or autologous tissue transfer, using fat and tissues from the abdomen (TRAM flap) or back (latissiumus muscle flap). Breast reduction surgery is a common procedure which involves removing excess breast tissue, fat, and skin with repositioning of the nipple-areolar complex (NAC). Cosmetic procedures include breast lifts (mastopexy), breast augmentation with implants, and procedures that combine both elements. Implants containing either silicone gel or saline are available for augmentation and reconstructive surgeries. Surgery can repair inverted nipples by releasing ductal tissues which are tethering. Breast lift with or without reduction can be part of upper body lift after massive weight loss body contouring. Any surgery of the breast carries with it the potential for interfering with future breastfeeding,[14][15][16] causing alterations in nipple sensation, and difficulty in interpreting mammography (xrays of the breast). A number of studies have demonstrated a similar ability to breastfeed when breast reduction patients are compared to control groups where the surgery was performed using a modern pedicle surgical technique.[17][18][19][20] Plastic surgery organizations have generally discouraged elective cosmetic breast augmentation surgery for teenage girls as the volume of their breast tissue may continue to grow significantly as they mature and because of concerns about understanding long-term risks and benefits of the procedure.[21] Breast surgery in teens for reduction of significantly enlarged breasts or surgery to correct hypolasia and severe asymmetry is considered on a case by case basis by most surgeons. Disorders This article needs additional citations for verification. Please help this article by adding reliable references. Unsourced material may be challenged and removed.(September 2007) This article or section is in need of attention from an expert on the subject. Please help recruit one or improve this article yourself. See the talk page for details. Please consider using {{Expert-subject}} to associate this request with a WikiProject Infections and inflammations These may be caused among others by trauma, secretory stasis/milk engorgement, hormonal stimulation, infections or autoimmune reactions. Repeated occurrence unrelated to lactation requires endocrinological examination. A 1930 Soviet poster. Are you taking care of your breasts? Harden your nipples with daily washing in cold water. A 1930 Soviet poster. Are you taking care of your breasts? Harden your nipples with daily washing in cold water. * Mastitis o bacterial mastitis o mastitis from milk engorgement or secretory stasis o mastitis of mumps o chronic intramammary abscess o chronic subareolar abscess o tuberculosis of the breast o syphilis of the breast o retromammary abscess o actinomycosis of the breast o Mondor’s disease o duct ectasia syndrome o breast engorgement Benign conditions Benign conditions include: * Congenital disorders o inverted nipple o supernumerary nipples/supernumerary breasts (polymazia / polymastia) /duplicated nipples * Aberrations of normal development and involution o cyclical nodularity o breast cysts o fibroadenoma - benign tumor o gynecomastia (males) o nipple discharge, galactorrhea o mammary fistula * Fibrocystic disease / Fibrocystic changes o cysts o epithelial hyperplasia o epithelial metaplasia o papillomas o adenosis * Pregnancy-related o galactocoele
" Junk is the ideal product... the ultimate merchandise. No sales talk necessary. The client will crawl through a sewer and beg to buy." - William S Burroughs
#4. To: All (#3)
that would be a good name for a rock band.
duplicated nipples
" Junk is the ideal product... the ultimate merchandise. No sales talk necessary. The client will crawl through a sewer and beg to buy." - William S Burroughs
#5. To: RickyJ (#0)
The Michaelson-Morely experiment consisted of splitting a beam of light into 90-degree paths. The beams were reflected back at the origin an recombined. A showing of a "fringe" would mean that an "aether" existed, ie, the speed of light was slowed along one path. The "fringe" didn't appear. Conclusion: no aether. Let's do a little thought experiment. According to Special Relativity, as an object approaches the speed of light it experiences a shortening in lenght and a slowing in time, except that the speed of a photon doesn't slowdown. So, if, according to the "Relativists," one beam length was shortened, but the speed of light was constant, how does that invalidate the experiment, ie, how does it show that there is no aether? It doesn't. Then there is the little problem of quantum entanglement that appears to violate the speed of light. This wouldn't be possible if the speed of light was an upper limit. Then there is the problem of mathematics driving physics to absurdities. Well, there is nothing settled. Flandern makes sense. Keep in mind that the idea of prions was considered to be lunacy at one time. Snowballs from space was a crazy idea. Perhaps Flandern's article on GPS and Relativity can shed some light :)
#6. To: RickyJ (#0)
I guess photons are made of gravitons. That might explain why you can find topics such as "Graviton mediated photon-photon scattering" when searching on the web.
#7. To: RickyJ (#0) (Edited)
I've found that considering all matter to be equivalent to light energy moving in an orbit is a useful viewpoint. It's sufficient to explain why matter cannot reach the maximum speed of light, no matter what that speed is. In string theory the orbit geometry is apparently synonymous with the "Calabi-Yau orbifold" (term worth putting in a google image search).
#8. To: RickyJ (#0)
Interesting article. Thanks. Can't comment on much as it's all far over my head, but it seems there must be some kind of "ether". Picture two weights in space tied together with a string. If they are spinning around one another, there's tension on the string. If they spin hard enough the tension breaks the string and they fly apart. The tension varies with spin speed even though the two weights do not move in relation to one another regardless of the spin speed. If the universe consisted of only these two weights with string and nothing else, then there would be no outside reference by which to measure the spinning. In that case it seems logical that there would be no tension on the string, and it would be impossible to induce such spinning and tension. But that seems intuitively rediculous. If we conclude that such spinning must be measurable by virtue of the tension on the string, even if there are no other objects in the universe, then it must be that there IS an outside reference by which spinning is measured even though there may be no outside bodies to measure it. Ergo, there MUST be something, some ether, which the two weights must be immersed in. My crude thinking on a somewhat related subject, anyway.
Pinguinite.com EcuadorTreasures.ec
#9. To: Pinguinite (#8)
Hence the same tension would appear if the space/either surrounding the weights was spun in relation to the weights. Interesting analogy, really makes one think. Thanks
The tension varies with spin speed even though the two weights do not move in relation to one another regardless of the spin speed.
A "conservative" is a draft animal that claims we must wear our yokes more or less as they're placed on us. A "liberal" is a draft animal that claims we have a right to shift the yokes from time to time.
"We'll know our disinformation program is complete when everything the American public believes is false." --- William Casey, Director CIA (Quote from internal staff meeting notes 1981)
#10. To: Pinguinite (#8)
Reminds me of some thoughts Mach had about inertia. There's a discussion on wiki, under "Mach's principle."
#11. To: RickyJ (#0)
"Any intelligent fool can make things bigger, more complex, and more violent. It takes a touch of genius -- and a lot of courage -- to move in the opposite direction." Collected Quotes from Albert Einstein
#12. To: RickyJ (#0)
Do we really know this? That's supposed to be an average, I suppose, because it doesn't seem possible it's a constant, as orbital distance isn't constant. If it's not a constant then it seems he's being vague in the description.
"We know, for example, that the Earth accelerates toward a point 20 arc-seconds in front of the visible Sun"
#13. To: RickyJ (#0)
"....The stability of planetary orbits tells us that gravity must propagate much faster than light. Accepting this reasoning, Isaac Newton assumed that the force of gravity must be instantaneous. Astronomical data support this conclusion. We know, for example, that the Earth accelerates toward a point 20 arc-seconds in front of the visible Sun -- that is, toward the true, instantaneous direction of the Sun. Its light comes to us from one direction, its “pull” from a slightly different direction. This implies different propagation speeds for light and gravity. It might seem strange that something so fundamental to our understanding of physics can still be a matter of debate. But that in itself should encourage us to wonder how much we really know about the physical world. In certain Internet discussion groups, “the most frequently asked question and debated topic is ‘What is the speed of gravity?,’” Van Flandern writes. It is heard less often in the classroom, but only “because many teachers and most textbooks head off the question.” They understand the argument that it must go very fast indeed, but they also have been trained not to let anything exceed Einstein’s speed limit. So maybe there is something wrong with Special Relativity after all. In The ABC of Relativity (1925), Bertrand Russell said that just as the Copernican system once seemed impossible and now seems obvious, so, one day, Einstein’s Relativity theory “will seem easy.” But it remains as “difficult” as ever, not because the math is easy or difficult (Special Relativity requires only high-school math, General Relativity really is difficult), but because elementary logic must be abandoned. “Easy Einstein” books remain baffling to almost all. The sun-centered solar system, on the other hand, has all along been easy to grasp. Nonetheless, Special Relativity (which deals with motion in a straight line) is thought to be beyond reproach. General Relativity (which deals with gravity, and accelerated motion in general) is not regarded with the same awe. Stanford’s Francis Everitt, the director of an experimental test of General Relativity due for space-launch next year, has summarized the standing of the two theories in this way: “I would not be at all surprised if Einstein’s General Theory of Relativity were to break down,” he wrote. “Einstein himself recognized some serious shortcomings in it, and we know on general grounds that it is very difficult to reconcile with other parts of modern physics...." read these? Exposing The Copernican Deception 1) Einstein’s Relativity hypothesis rescued heliocentricity from the findings of over 200 experiments which showed that the earth was not moving. ... http://www.fixedearth.com/knowledge%20impact.htm The Spiritual Roots of NASA's Big Bang Premise - Einstein (named "Person of the Century" before '99 ended) still dictates the ... but that it also accommodates Einstein's Relativity in all of its space, ... http://www.fixedearth.com/nasas_spiritual_roots.htm earthdeception - Moving-Earth DECEPTION! The Earth is NOT Moving ... http://www.fixedearth.com/the_bible/coperniciansales.html ..... Einstein: Relativity Hoax HERE. Plagiarist of the Century HERE. ... http://earthdeception.googlepages.com/ "The world also is stablished that it cannot be moved." Psalm 93:1 "He...hangeth the Earth upon nothing." Job 26:7 Jos 10:13 And the sun stood still, and the moon stayed, until the people had avenged themselves upon their enemies. [Is] not this written in the book of Jasher? So the sun stood still in the midst of heaven, and hasted not to go down about a whole day. Jos 10:14 And there was no day like that before it or after it, that the LORD hearkened unto the voice of a man: for the LORD fought for Israel. Hab 3:11 The sun [and] moon stood still in their habitation: at the light of thine arrows they went, [and] at the shining of thy glittering spear. way over my head!
#14. To: AllTheKings'HorsesWontDoIt (#13)
I honestly didn't know anyone thought the Sun and the universe were revolving around the Earth. The Bible verses you cite don't necessarily mean that the Sun is moving around the Earth or that the Earth does not move. The sun is moving, but not around the Earth and the Earth is moving but can't be moved out of its established path made up by God. I see no contradiction between Copernican System and the Bible.
God is always good!
#15. To: RickyJ (#14)
And I honestly don't have a clue about Einstein's theory of relativity, or any of the above. However, I find these links intriguing, and the fact that some of them propose that some of these so-called "scientific" theories are based on the Kabbalah, with the aim of discrediting the creation story and the need for a savior, in light of all the other things I've learned about the Kabbalists, gives me pause to wonder....and I don't think I'm the only one....doing a google search, there seem to be more questioning it since I first ran across this a few weeks ago. I'll just keep putting the "flat earth theory" out there [actually, the Bible refers to the CIRCLE of the earth], and watch what others say. I'm certainly not married to scientific theories, and would find it a great joke if they were proved wrong.
I honestly didn't know anyone thought the Sun and the universe were revolving around the Earth.
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