How long has string theory been studied?
548875
As with so many major studies in physics, string theory has developed gradually from groundwork laid by many others --\n\n1915 - Emmy Noether\n1931 - Georges De Rham\n1943 - Shiing-Shen Chern\n\nThis next scientist is generally credited with developing the modern form of string theory\n1954 - Eugenio Calabi\n\nThis website has more details on the various contributions --\nhttp://www.superstringtheory.com/history/history3.html
172699
Before I start, I am a Biologist with an interest in theoretical physics, not actually a physicist, so my grasp of the finer detail may be shaky in places.  \nBasically string theory is an attempt to unify the elemental forces within the universe (Weak nuclear, Strong nuclear, Electromagnetic, and Gravity).  The theory postulates that various sub atomic particles are not particles but loops of vibrating energy so small that they have an almost “point” existence.  For string theory to work it is necessary to visual up to 26 separate dimensions (the 3 we know and love as well as other "compacted dimensions").  This may be the theory's downfall as it is next to impossiable to prove the existance of these extra dimensions and without them string theory just does not work!\nString theory has given rise to m-theory (which uses vibrating membranes (or 'branes if your a cool physicist) in place of strings), which may well prove to be a more accurate (if still incomplete) model for the way the universe works on both a sub atomic and an astrological level.
1038716
String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles) that are the basis of the Standard Model of particle physics. For this reason, string theories are able to avoid problems associated with the presence of pointlike particles in theories of physics. Studies of string theories have revealed that they predict not just strings, but also higher-dimensional objects.\n\nThe basic idea is that the fundamental constituents of reality are strings of energy of the Planck length (about 10-35 m) which vibrate at resonant specific frequencies[1]. Another key claim of the theory is that no measurable differences can be detected between strings that wrap around dimensions smaller than themselves and those that move along larger dimensions (i.e., physical processes in a dimension of size R match those in a dimension of size 1/R). Singularities are avoided because the observed consequences of "big crunches" never reach zero size. In fact, should the universe begin a "big crunch" sort of process, string theory dictates that the universe could never be smaller than the size of a string, at which point it would actually begin expanding.\n\nInterest in string theory is driven largely by the hope that it will prove to be a theory of everything. It is a possible solution of the quantum gravity problem, and in addition to gravity it can naturally describe interactions similar to electromagnetism and the other forces of nature. Superstring theories include fermions, the building blocks of matter, and incorporate supersymmetry. It is not yet known whether string theory will be able to describe a universe with the precise collection of forces and matter that is observed, nor how much freedom to choose those details that the theory will allow. String theory as a whole has not yet made falsifiable predictions that would allow it to be experimentally tested, though various special corners of the theory are accessible to planned observations and experiments. Hence critics of string theory occasionally remark that the theory "... is not even wrong," quoting a quip attributed to Wolfgang Pauli.\n\nWork on string theory has led to advances in mathematics, mainly in algebraic geometry. String theory has also led to other theories, supersymmetric gauge theories, which will be tested at the new Large Hadron Collider experiment.
510510
I would have to go with the Planck length on this one, which is a millionth of a billionth of a billionth of a billionth of a centimeter!  \n\nThe reason I say this: According to String Theory, strings are that long, and they are the fundamental building block of all matter.  Therefore, nothing exists that is smaller than that, so it is useless to have a smaller measurement.
1045220
The Four fundamental components in the string theory are  gravity, electromagnetism, and the weak and strong nuclear forces.\n\n  The impact of the string theory on observance of gravitational law allowed for the standard physics model to describe the effects of gravity in the world of quanta.
1151026
According to classical physics 3: length, wideth and depth.\nModern physics add to that a fourth dimension - time.\nThose we now for certain exist. But there could be more (as much as 10 or 11 according to superstring theory).
51307
String theory is a physical theory that attempts solve several outstanding problems in modern physics.  One problem deals with the unification of the fundamental forces of nature.  Ever since electricity and magnetism were found to be different manifestations of the same force, people have wondered if all the forces of nature are related somehow.  We all know that Einstein's general theory of relativity describes gravity in terms of space-time geometry.  Wouldn't it be great if we could describe all the fundamental force of nature using geometry too.  This is one problem string theory is attempting to solve.  Another problem deals with fundamental particles.  We all know about protons, electrons, and neutrons, but there are also a lot of other particles that don't seem to have much to do with anything.  Why do they exist?  How are they related? Why do they have the physical properties they do?  These are all questions that will hopefully be answered by the string theory.  Lastly, the main reason the string theory was created was to solve a math problem in classical/quantum electrodynamics.  The equations describing the electric field end up with some technical problems that ultimately can be traced to the fact that we are trying to describe pointlike particles.  String theory just gets rid of the pointlike particles and replaces them with strings vibrating in extra dimensions of space-time.
115605
Very simply put, string theory (now most often called "M" theory) is an attempt to unite quantum physics with relativity; we hope that by doing so we can develop a set of equations that will tie together the four fundamental forces of nature. The direct relationship of three of those forces have been linked, but gravity so far remains the "outsider."
308069
String theory is a step in the direction for the GUT.  But string theory itself is out the window.  GUT will mostly likely be a hybrid of string and quantum.  Each answer some of the most important fundamental questions, but not the same ones and not all of them.  Essentially string theory just states matter is made up of vibrating strings of energy.  For a good book on the subject, three roads to quantum gravity by smolin is excellent.  He is partial to quantum theory but gives both justice and goes a little into some radical ideas that don't branch from either quantum or relativity.
91646
String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles) that are the basis of the Standard Model of particle physics. For this reason, string theories are able to avoid problems associated with the presence of pointlike particles in a physical theory. Studies of string theories have revealed that they require not just strings but also higher-dimensional objects.\n\nThe basic idea is that the fundamental constituents of reality are strings of energy of the Planck length (about 10-35 m) which vibrate at resonant specific frequencies[1]. Another key claim of the theory is that no measurable differences can be detected between strings that wrap around dimensions smaller than themselves and those that move along larger dimensions (i.e., effects in a dimension of size R equal those whose size is 1/R). Singularities are avoided because the observed consequences of "big crunches" never reach zero size. In fact, should the universe begin a "big crunch" sort of process, string theory dictates that the universe could never be smaller than the size of a string, at which point it would actually begin expanding.\n\nInterest in string theory is driven largely by the hope that it will prove to be a theory of everything. It is a possible solution of the quantum gravity problem, and in addition to gravity it can naturally describe interactions similar to electromagnetism and the other forces of nature. Superstring theories include fermions, the building blocks of matter, and incorporate supersymmetry. It is not yet known whether string theory is able to describe a universe with the precise collection of forces and matter that is observed, nor how much freedom to choose those details the theory will allow. String theory as a whole has not yet made falsifiable predictions that would allow it to be experimentally tested, though various special corners of the theory are accessible to planned observations and experiments.\n\nWork on string theory has led to advances in mathematics, mainly in algebraic geometry. String theory has also led to other theories, supersymmetric gauge theories, which will be tested at the new Large Hadron Collider experiment.
561306
you should read more into string theroy and the M theory.  they are both very interesting.  it is hard to wrap your mind around but  this is just one universe that goes along a membrane of universes that goes on infinetely.  the science channel often has show that explin all this much better and they make it pretty easy to understand.
167035
ok this is a video and ther is also a book on it called the eligant universe by brian greene. http://www.pbs.org/wgbh/nova/elegant/program.html\nthis will help explain theory and the science needed to understand string theory it is good.
104678
How long is a piece of string?\n\nYour question is far too general to be answered.
1164474
String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles) that are the basis of the Standard Model of particle physics. For this reason, string theories are able to avoid problems associated with the presence of pointlike particles in a physical theory. Studies of string theories have revealed that they require not just strings, but also higher-dimensional objects.\n\nThe basic idea is that the fundamental constituents of reality are strings of energy of the Planck length (about 10-35 m) which vibrate at resonant specific frequencies[1]. Another key claim of the theory is that no measurable differences can be detected between strings that wrap around dimensions smaller than themselves and those that move along larger dimensions (i.e., physical processes in a dimension of size R match those in a dimension of size 1/R). Singularities are avoided because the observed consequences of "big crunches" never reach zero size. In fact, should the universe begin a "big crunch" sort of process, string theory dictates that the universe could never be smaller than the size of a string, at which point it would actually begin expanding.\n\nInterest in string theory is driven largely by the hope that it will prove to be a theory of everything. It is a possible solution of the quantum gravity problem, and in addition to gravity it can naturally describe interactions similar to electromagnetism and the other forces of nature. Superstring theories include fermions, the building blocks of matter, and incorporate supersymmetry. It is not yet known whether string theory will be able to describe a universe with the precise collection of forces and matter that is observed, nor how much freedom to choose those details that the theory will allow. String theory as a whole has not yet made falsifiable predictions that would allow it to be experimentally tested, though various special corners of the theory are accessible to planned observations and experiments. Hence critics of string theory occasionally remark that the theory "... is not even wrong," quoting a quip attributed to Wolfgang Pauli.\n\nWork on string theory has led to advances in mathematics, mainly in algebraic geometry. String theory has also led to other theories, supersymmetric gauge theories, which will be tested at the new Large Hadron Collider experiment.
625008
String theory is a model of fundamental physics whose building blocks are one-dimensional extended objects (strings) rather than the zero-dimensional points (particles) that are the basis of the Standard Model of particle physics. For this reason, string theories are able to avoid problems associated with the presence of pointlike particles in a physical theory. Studies of string theories have revealed that they require not just strings, but also higher-dimensional objects.\n\nThe basic idea is that the fundamental constituents of reality are strings of energy of the Planck length (about 10-35 m) which vibrate at resonant specific frequencies[1]. Another key claim of the theory is that no measurable differences can be detected between strings that wrap around dimensions smaller than themselves and those that move along larger dimensions (i.e., physical processes in a dimension of size R match those in a dimension of size 1/R). Singularities are avoided because the observed consequences of "big crunches" never reach zero size. In fact, should the universe begin a "big crunch" sort of process, string theory dictates that the universe could never be smaller than the size of a string, at which point it would actually begin expanding.\n\nInterest in string theory is driven largely by the hope that it will prove to be a theory of everything. It is a possible solution of the quantum gravity problem, and in addition to gravity it can naturally describe interactions similar to electromagnetism and the other forces of nature. Superstring theories include fermions, the building blocks of matter, and incorporate supersymmetry. It is not yet known whether string theory will be able to describe a universe with the precise collection of forces and matter that is observed, nor how much freedom to choose those details that the theory will allow. String theory as a whole has not yet made falsifiable predictions that would allow it to be experimentally tested, though various special corners of the theory are accessible to planned observations and experiments. Hence critics of string theory occasionally remark that the theory "... is not even wrong," quoting a quip attributed to Wolfgang Pauli.\n\nWork on string theory has led to advances in mathematics, mainly in algebraic geometry. String theory has also led to other theories, supersymmetric gauge theories, which will be tested at the new Large Hadron Collider experiment.\n\nTime travel in theory:\n\nSome theories, most notably special and general relativity, suggest that suitable geometries of spacetime, or certain types of motion in space, may allow time travel into the past and future if these geometries or motions are possible. Concepts that aid such understanding include the closed timelike curve.\n\nAlbert Einstein's special theory of relativity (and, by extension, the general theory) very explicitly permits a kind of time dilation that would ordinarily be called time travel. The theory holds that, relative to a stationary observer, time appears to pass more slowly for faster-moving bodies: for example, a moving clock will appear to run slow; as a clock approaches the speed of light its hands will appear to nearly stop moving. The effects of this sort of time dilation are discussed further in the popular "twin paradox".\n\nA second, similar type of time travel is permitted by general relativity, where a distant observer sees time passing more slowly for a clock at the bottom of a deep gravity well, and a clock lowered into a deep gravity well and pulled back up will indicate that less time has passed compared to a stationary clock that stayed with the distant observer.\n\nThese effects are to some degree similar to hibernation or hypothetical suspended animation (which slow down the rates of chemical processes in the subject), and only allow "time travel" toward the future: never backward. They do not violate causality. This is not typ
246328
String theory is still quite new in the world of physics, but it has drawn tremendous attention to all physicists around the world. \nFor the last 80 years or so physicists have been trying to find a theory that will combine the theories of quantum mechanics and general relativity. These two theories describe everything in the universe. General relativity does this on the scale of the very large e.g. planets, galaxies and so on. When it comes to subatomic scale, like protons, quarks etc. general relativity breaks down. This is where quantum mechanics is very accurate, but quantum mechanics does not work when applied to the very large objects. \nGeneral relativity basically deals with gravity and has a calm feeling to it. The predictions it makes is always sort of neat and precise.\nQuantum mechanics on the other hand deals with the uncertainty principal and has a very chaotic feel to it.\n\n\nString theory is what physicisits hope and believe might be the theory combines these two super theories. String theory predicts that every particle (even quarks) are made up of much, much smaller particles called strings. They are not really particles, they are actually vibrating strands of energy. Each of these strands vibrate in a different way. \n\nThe mathematics behind string theory works so well that many believe string theory has to be true, but unfortunately there is currently no way to prove string theory with experiment. If string theory is true, then some of our notions of the universe will have to change dramatically. We will have to accept that we actually live in an 11-dimensional universe.
1125292
Superstring theory is being hammered by many different new physical obervations. Proponents keep adding one fudge factor after another to try to save the theory from sinking.\nThe big bang theory has taken a beating, lately,  but not as bad as superstring theory.\nEvolution is solid and has been so for more than 100 years. But three methods of Lamarkian evolution, at a molecular biology level have recently been discovered. Especially the second one.(methylationof genes, and microsatellite r.n.a. in sperm and the massive random insertion of a jumping gene sequence in neurological cells causing random cell diversity.).\nDan the Answers-man