Thorough in information, few grammatical errors -
Honors English II : B
21 February 1996
Scientific Advancements Due to Relativity
The scientific world of the late nineteenth and early twentieth century believed they discovered all of the laws and equations of the natural world. Those scientists based their works and studies on the rules of classical physics. Only a few humans remained as revolutionary thinkers and physicists within the community of that time period. Albert Einstein fell into the rare revolutionary group of imaginative scientists. Einstein discovered many revolutionary equations and theories during his lifetime. Although one of the half respectable theorists of the twentieth century, he did not perform well in grade school or college. He spent most of his career researching and studying in Europe, starting in the Swiss Patent Office. With the ample and serene conditions at the Patent Office, Einstein could ponder on his theories and thoughts (Motz and Weaver 243-7).
At the Patent Office, he discovered the Special Theory of Relativity and the Photoelectric Effect (Motz and Weaver 244; 'Quantum Theory' 4). Then in 1910, Einstein moved to the University of Prague for a full professorship. Mr. Einstein developed the basis of the General Theory of Relativity in Prague. The Annalen der Physik, a German science publication, published his General Theory of Relativity, which shows that 'space is not merely a backdrop against which the events of the universe unfold, but that space itself has a fundamental structure that is affected by the energy and masses of the bodies it contains.' This curvature of space propelled him to include the newly-formed positively curved geometry of Georg Riemann. The positively curved geometry contained curved lines and planes replacing the old Euclid straight lines and planes. After the discovery of the General Theory of Relativity, he began to 'formulate mathematical framework that would unite both electromagnetism and gravitation,' which is now called the unified field theory. When the Nazis overran Germany in 1932, Einstein fled to the United States of America where he continued his work at Princeton. He was a professor in the Institute for Advanced Study at Princeton where he died during practice in 1955 (Motz and Weaver 247-50). The two theories of relativity were the most recognized theories of Einstein's works. Likewise, they produced the most significant effects onto the scientific world. Einstein's composition of the theories of relativity impacted the scientific community by spurring the intellectual growth of quantum theory and mechanics, by theorizing and discovery of black holes, and by the beginning of formulating new theories and experiments in the area of time travel.
Einstein's development of his famed equations and theories caused the scientific society to look at classical physics at a whole new perspective. At the same time of the discovery of relativity, modernistic physicists were developing a new theory called quantum theory. This new-sprung theory is 'based on using the concept of the quantum unit describe the dynamic properties of subatomic particles and the interactions of matter and radiation.' Max Planck is often called the 'founder' of quantum theory who stated that 'energy can be emitted or absorbed by matter in only small, discrete units called quanta.' Quantum theory solved many problems that baffled classical scientists who received current and detailed observations that did not comply with the rules of classical physics. First, scientist believed that light was emitted over a broad spectrum of light (wavelength). As observations showed, certain light was only emitted in specific, narrow wavelengths. Next, the corpuscular (particle) theory, hypothesizes light as a stream of particles, and the wave theory, hypothesizes light as electromagnetic waves, coexisted as the early twentieth century theories of light. Lastly, there was an absence of a molecular basis for thermodynamics. Most classical physicists conceded the impossibility of framing a theory of molecular action that embraced the phenomena of thermodynamics, radiation, and electrical phenomena as they were then understood ('Quantum Theory' 1). Einstein used Planck's concept of a quantum to explain certain properties of the photoelectric effect--an experimentally observed phenomenon in which electrons are emitted from metal surfaces when radiation falls on these surfaces ('Quantum Theory' 2-3). With the classical physics explanation, energy was proportional to the intensity of the radiation. Einstein determined the intensity of radiation was independent of the intensity of radiation which was dependent on the frequency of the radiation. A critical frequency, where any frequency below that point the object emitted no electrons, was discovered by Einstein's research of the photoelectric effect ('Quantum Theory' 4). The publication of the theories of relativity reformed the world of the quantum. When scientists dissected his theories, they found that they broke down under great gravitational forces and minuet lengths. These discrepancies motivated physicists to search for new hypothesizes about the behavior and existence of particles and objects of a very diminutive size such as subatomic particles. These modern studies were the establishment of quantum mechanics (Motz and Weaver 282-3).
About a decade after the theorization of relativity, scientists began to build a unique field of physics explaining the subatomic world of electrons, protons, neutrons, and eventually quarks. Physicists named this subatomic field, quantum mechanics. The basis of quantum mechanics actually started to form around the time of the discovery of relativity (Motz and Weaver 282). In 1911, Ernest Rutherford detected that atoms consisted of negatively charged particles revolving around a positively charged nucleus. Using James Clerk Maxwell's equations, scientists speculated that the electrons would continuously emit electromagnetic energy, and lose all of its energy, then fall into the nucleus. Two years later, Niels Bohr solved the instability of the Rutherford model by hypothesizing the electrons moved in fixed orbits due to emitting or absorbing quantum radiation. The scientific world accepted this theory, but some doubt and inconsistency arose from the Bohr model of the atom. First of all, Bohr's model contained both classical and quantum physics, which were two entirely different fields of science. Also, the model was only in accordance with the hydrogen atom, and not any other of the atoms ('Quantum Theory' 3).
The incorrect models of atoms and particles propelled scientists to explore new and unfamiliar fields of science to discover new theories and models. Einstein's discovery of the photoelectric effect and relativity launched scientists forward to expand on his theories and thoughts. The Emission Theory was one of the first to further develop Einstein's photoelectric effect. Throughout the past couple decades, physicists discovered that light has both wave and particle properties. In 1924, the Emission Theory answered this problem by combining the ideas within the photoelectric effect and the theories of relativity to fuse together the corpuscular and the wave theories of light (Motz and Weaver 282-3). In the same year, Louis de Broglie suggested that because electromagnetic waves show particle characteristics, so in contrast, particles should show some wave characteristics. De Broglie's wave theory is often thought as the foundation of quantum mechanics. He stated that quantum mechanics must have its own set of rules and concepts, not sharing some rules from classical and quantum theory ('Quantum Theory' 2). This concept of the wave theory led to Erwin SchrÃÂµdinger developing a wave equation that describes the wave properties of a particle, more importantly atoms. SchrÃÂµdinger's wave equation only gave certain discrete solutions, now called quantum numbers. They are integers developed in particle physics to give the magnitudes of characteristic quantities of particles. This equation worked on all elements, unlike the Bohr atom, and was in agreement with earlier quantum theories ('Quantum Theory' 4). Another important quantum mechanical field was matrix mechanics, developed by Max Born and Ernst Jordan. They solved that the momentum and position of an electron were represented by infinite matrices. Different matrices exist for different properties, such as energy and angular momentum. The matrices could be solved to make predictions of other properties ('Quantum Theory' 3). With the founding of matrix mechanics, Werner Heisenberg postulated that scientists could not specify the position and velocity of the electron, because the disturbance of measuring the electron would completely throw off the observations. This assumption was named the Uncertainty Principle. These theories and equations constructed the foundation of quantum mechanics and quantum theory. Quantum mechanics and theory had tremendous effects on scientific thought and theory, which is analogous to relativity on its effects ('Quantum Theory' 5).
When early twentieth century scientists solved Einstein's equations, many theories and concepts originated from their minds, and the concept of a black hole was one of the most significance ideas. Shortly after Einstein published his general theory of relativity, Karl Schwarzschild developed the concept of a black hole in 1916. A black hole is an extremely dense object that the escape velocity of it is so great that nothing can escape from its vicinity, not even light. Black holes form at the end of the stellar evolution cycle. As the star ends its life, it runs out of fuel, and it cannot support the gravitational force that it is putting on itself. Depending on the star's core mass, it can either become a white dwarf, neutron star, or black hole. The core mass has to be at least 1.7 solar masses to collapse into a black hole. In accordance with general relativity, the gravitation of the black hole severely alters space and time near itself. For instance, when matter travels closer to the black hole, time slows down. Once an object enters the Schwarzschild radius (3km multiplied by mass, in solar units) or horizon, time completely stops. An ergosphere forms outside the horizon that consists of matter that is forced to rotate around the black hole and by theory it can emit light and energy. Nothing can escape outside the horizon; therefore, the black hole appears totally black, and all that is visible is the ergosphere. The former star now collapses into a singularity, a dimensionless object with infinite density ('Black Hole' 1). At the center of the black hole, the gravitational force is so immense, electrons would be ripped from their nuclei and nuclei would be torn apart. In 1963, Roy Kerr assumed that the collapsing star would be spinning, like any other star, changing the properties of the singularity. The star would collapse into a ring instead of a point. The altered properties include the curvature and gravitational force would be finite, comparing with infinite gravitational force and curvature of the Schwarzschild model. At the center of a Schwarzschild black hole, the infinite curvature would make objects in the black hole would appear to be at stand-still as viewed by by-standers. The travelers would never escape the depths of the black hole. To flee from it, an object would have to travel faster than the speed of light, impossible by Einstein's equations (mass becomes infinite). Even if some being successful traveled through the black hole, communication is impossible through the horizon. By theory, the black hole has a companion connected by the Einstein-Rosen bridge. It is often considered a mathematical quirk, and it is necessary for the theory to be mathematically consistent. The Einstein-Rosen bridge acts like a wormhole within the universe, but the Kerr black hole behaves like a gateway to another universe. The concept of the black hole deduced that the escape velocity is greater than the speed of light. When this event occurs, light actually orbits in a circle around the singularity. Light can only bend as space is bending with light itself. This can only happen when an object has completely pinched off a piece of space-time along with it. The light beam is circulating in a hypersphere, a four-dimensional sphere. Space itself has now been 'ripped' from the space-time continuum (Kaku 223-6).
During the 1970's, physicists theorized a new type of black holes. Especially one scientist, Stephen Hawking, extensively researched and developed the ideas and theories about primordial black holes. Based on observations from the SAS-2 satellite, a satellite that measures cosmic background of gamma radiation, it is estimated that in the Milky Way, there are a density of 200 million primordial black holes per cubic light-year. This density amounts to the closest black hole is probably at least as far away as Pluto. Primordial black holes are diminutive, a radius of 10-13cm (about the size of a proton or neutron), with a mass of a billion tons (mass of a mountain). With a colossal amount of mass inside a tiny area, the black hole has a very high temperature of 120 billion Kelvin, which corresponds to a rate of 6,000 megawatts (six nuclear power plants). Primordial black holes can create electron-positron pairs and no-mass particles, like photons, gravitons, and neutrinos, with such a high temperature. The equations for the emission of energy also apply to black holes, which is emission of energy is proportional to the surface gravity and inversely proportional to the mass. In other words, as the mass becomes smaller, the greater the energy emitted. For example, a dense black hole emits very few particles, but particles can escape rapidly from primordial black holes. When black holes or any object emits particles, the mass and size steadily decrease. So in ample time, black holes will evaporate; normal black holes (one solar mass) will evaporate in 1066 years, and primordial black holes will evaporate in 1010 years. They do not just disappear when it is evaporated. But as the mass travels closer to zero, the energy emitted is so great, a tremendous explosion occurs. The magnitude of this explosion would depend on the number of existing species of elementary particles (e.g. quarks, leptons, pions, etc.). Six types of elementary particles are know today. With six particles in the explosion, it would be around ten million one-megaton hydrogen bombs. Stephen Hawking explains how the big bang could be a black hole explosion on a very large scale:
The big bang resembles a black-hole explosion but on a vastly larger scale. One therefore hopes that an understanding of how black holes create particles will lead to a similar understanding of how the big bang created everything in the universe. In a black hole matter collapses and is lost forever but new matter is created in its place. It may therefore be that there was an earlier phase of the universe in which matter collapsed, to be re-created in the big bang (6).
R. Hagedorn hypothesized that there is an infinite number of particles at higher mass. When the black hole becomes smaller and denser, it may produce many other particles not found anywhere else but in dying primordial black holes. The explosion with this hypothesis would be 100,000 times as large as the explosion with only six particles.
As mentioned earlier, black holes cannot emit particles outside of the Schwarzschild radius. Physicists of the 1970's conformed a hypothesis for this phenomena. Defined by quantum mechanics, pairs of 'virtual' particles and antiparticles are constantly annihilating each other in space. They are called virtual particles, because they cannot be detected with a particle detector, but the indirect effects can be observed. In the vicinity of the black hole, the gravitational force of the black hole rips apart the antiparticle and particle pair. The majority of the time, the antiparticle falls into the black hole. As the neutrality of the pair breaks apart, the antiparticle is now the complete opposite of a particle, as in time, mass, and velocity. When the pair are together, the particle's forces overwhelm the antiparticle's forces, therefore the antiparticle's presence is undetectable by just common observations. While the antiparticle falls into the black hole, the antiparticle is actually traveling outside of the black hole as viewed by a by-stander. This world of the antiparticle can be thought as a video tape of the a antiparticle traveling into a black hole in the anti-world, but to imagine the path of the antiparticle in this universe, you would have to play the tape backwards to view the path of the antiparticle in this world. This phenomena is only possible in quantum mechanics, but impossible in classical physics (Hawking 35, 37-39).
While scientists solved Einstein's relativity equations for different equations, concepts, and theories, they stumbled upon the fact that general relativity allows time travel. But Einstein's equations only permit some sorts of time travel. For example, traveling near the speed of light is a form of time travel according to the general theory of relativity. Another popular theory is to twist time into a circle. But the energies necessary to perform that feat, Einstein's equations break down, and quantum mechanics take over. As stated in general relativity, the curvature of space and time is determined by the matter-energy content of the universe. So it is possible to find configurations of matter-energy powerful enough to force time to bend and to allow time travel. Modern scientists believe when man masters the hyperspace theory, where Einstein's theory of gravity and quantum theory unites, man can incorporate the full power of wormholes and dimensional windows. But some scientists reject the theory of possible time travel in the future. For instance, if time-machines were abundant as carts, then havoc would erupt in our universe. People would try to change the course of history. History would cease to exist in that case. Stephen Hawking stated that with the evidence that future tourists have not bombarded us, time travel is not possible. But if time travel time is possible, people have many problems to contend with, especially paradoxes. In general, most paradoxes can be broken down into one of two principal types, either meeting your parents before you were born or the man with no past (Kaku 233-6). Here is an example of a man with no past:
A baby girl is mysterious dropped off at an orphanage in Cleveland in 1945. 'Jane' grows up lonely and dejected, not knowing who parents are, until one day in 1963 she is strangely attracted to a drifter. She falls in love with him. But just when things are finally looking up for Jane, a series of disasters strike. First, she becomes pregnant by the drifter, who then disappears. Second, during the complicated delivery doctors find that Jane has both sets of sex organs, and to save her life, they are forced to surgically convert 'her' to a 'him.' Finally, a mysterious stranger kidnaps her baby from the delivery room. Reeling from these disasters, rejected by society, scorned by fate, 'he' becomes a drunkard and drifter. Not only has Jane lost her parents and her lover, but he has lost his only child as well. Years later, in 1970, he stumbles into a lonely bar, called Pop's Place, and spills out his pathetic story to an elderly bartender. The sympathetic bartender offers the drifter the chance to avenge the stranger who left he pregnant and abandoned, on the condition that he join the 'time travelers corps.' Both of them enter a time machine, and the bartender drops off the drifter in 1963. The drifter is strangely attracted to a young orphan woman, who subsequently becomes pregnant. The bartender then goes forward 9 months, kidnaps the baby girl from the hospital, and drops off the baby in an orphanage back in 1945. Then the bartender drops off the thoroughly confused drifter in 1985, to enlist in the time travelers corps. The drifter eventually gets his life together, becomes a respected and elderly member of the time travelers corps, and then disguises himself as a bartender and has his most difficult mission: a date with destiny, meeting a certain drifter at Pop's Place in 1970 (Kaku 236-7).
Time travel is a component of general relativity that has not been fully harnessed by man, but comparable to others, it is not alone. Right now, time travel is only measured in minuet fractions of a second, but many several centuries in the future, it will be measured in years and centuries.
Einstein shook the modern scientific world by the publication of relativity. Scientists became revolutionized by these unusual but mathematically complex equations and theories. A few of the major fields transformed by relativity were quantum theory and mechanics, concepts of black holes, and time travel. As the decades past, physicists expanded on that knowledge held within the theories of relativity. Eventually the ideas and concepts were taught in universities, and now even high school. Now at the closing of the twentieth century, the general public has the basic understanding of relativity. Einstein's has spread from the highest areas of knowledgeable theoretical physics down to the majority of educated typical people. Einstein's popularity has steadily increased from an average-minded patent clerk to the finest human mind of scientific and mathematical ability. Einstein's discovery of relativity is man's greatest accomplishment of the twentieth century, and is equivalent or greater than Newton's laws of gravity and motion as the greatest human conception of the natural world for man's history on earth.
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Hawking, Stephen W. 'The Quantum Mechanics of Black Holes.' Scientific American. New York: Scientific American, Jan. 1977: 34-40.
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