The Scientific Possibilities of Time Travel

Stories regarding travel into the past and the future have long captured our imagination, but the question of whether time travel is possible is a thorny one that gets right to the heart of understanding what physicists mean when they use the word time.   Modern physics teaches us that time is one of the most mysterious aspects of our universe, though it may at first seem straightforward. Einstein revolutionized our understanding of the concept, but even with this revised understanding, some scientists still ponder the question of whether or not ​time actually exists or whether it is a mere stubbornly persistent illusion (as Einstein once called it). Whatever time is, though, physicists (and fiction writers) have found some interesting ways to manipulate it to consider traversing it in unorthodox ways. Time and Relativity Though referenced in H.G. Wells The Time Machine (1895), the actual science of time travel didnt come into being until well into the twentieth century, as a side-effect of Albert Einsteins theory of general relativity (developed in 1915). Relativity describes the physical fabric of the universe in terms of a 4-dimensional spacetime, which includes three spatial dimensions (up/down, left/right, and front/back) along with one time dimension. Under this theory, which has been proven by numerous experiments over the last century, gravity is a result of the bending of this spacetime in response to the presence of matter. In other words, given a certain configuration of matter, the actual spacetime fabric of the universe can be altered in significant ways. One of the amazing consequences of relativity is that movement can result in a difference in the way time passes, a process known as time dilation. This is most dramatically manifested in the classic Twin Paradox. In this method of time travel, you can move into the future faster than normal, but theres not really any way back. (Theres a slight exception, but more on that later in the article.) Early Time Travel In 1937, Scottish physicist W. J. van Stockum first applied general relativity in a way that opened the door for time travel. By applying the equation of general relativity to a situation with an infinitely long, extremely dense rotating cylinder (kind of like an endless barbershop pole). The rotation of such a massive object actually creates a phenomenon known as frame dragging, which is that it actually drags spacetime along with it. Van Stockum found that in this situation, you could create a path in 4-dimensional spacetime which began and ended at the same point - something called a closed timelike curve - which is the physical result that allows time travel. You can set off in a space ship and travel a path which brings you back to the exact same moment you started out at. Though an intriguing result, this was a fairly contrived situation, so there wasnt really much concern about it taking place. A new interpretation was about to come along, however, which was much more controversial. In 1949, the mathematician Kurt Godel - a friend of Einsteins and a colleague at Princeton Universitys Institute for Advanced Study - decided to tackle a situation where the whole universe is rotating. In Godels solutions, time travel was actually allowed by the equations if the universe were rotating. A rotating universe could itself function as a time machine. Now, if the universe were rotating, there would be ways to detect it (light beams would bend, for example, if the whole universe were rotating), and so far the evidence is overwhelmingly strong that there is no sort of universal rotation. So again, time travel is ruled out by this particular set of results. But the fact is that things in the universe do rotate, and that again opens up the possibility. Time Travel and Black Holes In 1963, New Zealand mathematician Roy Kerr used the field equations to analyze a rotating black hole, called a Kerr black hole, and found that the results allowed a path through a wormhole in the black hole, missing the singularity at the center, and make it out the other end. This scenario also allows for closed timelike curves, as theoretical physicist Kip Thorne realized years later. In the early 1980s, while Carl Sagan worked on his 1985 novel Contact, he approached Kip Thorne with a question about the physics of time travel, which inspired Thorne to examine the concept of using a black hole as a means of time travel. Together with the physicist Sung-Won Kim, Thorne realized that you could (in theory) have a black hole with a wormhole connecting it to another point in space held open by some form of negative energy. But just because you have a wormhole doesnt mean that you have a time machine. Now, lets assume that you could move one end of the wormhole (the movable end). You place the movable end on a spaceship, shooting it off into space at nearly the speed of light. Time dilation kicks in, and the time experienced by the movable end is much less than the time experienced by the fixed end. Lets assume that you move the movable end 5,000 years into the future of the Earth, but the movable end only ages 5 years. So you leave in 2010 AD, say, and arrive in 7010 AD. However, if you travel through the movable end, you will actually pop out of the fixed end in 2015 AD (since 5 years have passed back on Earth). What? How does this work? Well, the fact is that the two ends of the wormhole are connected. No matter how far apart they are, in spacetime, theyre still basically near each other. Since the movable end is only five years older than when it left, going through it will send you back to the related point on the fixed wormhole. And if someone from 2015 AD Earth steps through the fixed wormhole, theyd come out in 7010 AD from the movable wormhole. (If someone stepped through the wormhole in 2012 AD, theyd end up on the spaceship somewhere in the middle of the trip and so on.) Though this is the most physically reasonable description of a time machine, there are still problems. No one knows if wormholes or negative energy exist, nor how to put them together in this way if they do exist. But it is (in theory) possible.

John Milton s Paradise Lost - 2283 Words

The world’s history has been a topic that has interested millions over the years. The desire to know and understand the cultures and events of the past has been a one that many societies in the past and present have had. An effective way to access the heart of a culture’s history, traditions, and beliefs is to look into the stories they tell, the legends and myths they pass down to their young. This is because storytelling has been a tradition of humanity since time immemorial, and has been the only way of passing culture on to future generations for millennia. From this tradition, the Epic arose, tales of mighty heroes, gods, and monsters, told in the form of poems to convey ideals, beliefs, and traditions. Hundreds of Epics have been written, and among them, many stand out, especially Virgil’s The Aeneid, Beowulf, and John Milton’s Paradise Lost, as they prove to be impactful and useful in the analysis of changes in the relationship between divinity, def ined as of or relating to a god, celestial, religious, or sacred (dictionary.com), and mankind, as well as the idea of fate as it relates to mankind. The Aeneid, being a classical Greco-Roman Epic, shows an earlier age of humanity, one vastly different from the present one, showcases some of the roots of modern storytelling and the â€Å"hero’s quest.† Beowulf also shows some of these roots, but additionally tells of a shift in culture brought on by time and location. John Milton’s Paradise Lost, the most recent of these threeShow MoreRelatedJohn Milton s Paradise Lost985 Words   |  4 PagesJohn Milton’s Paradise Lost is a paradox of morality and character definitions. After reading multiple articles, the largest concerning topic was the hero status of an inherently evil character. The issue lies within defining what a hero is and is not in terms of epic poetry. John Milton’s refusal to clarify a hero shows this paradox he has created is a some thing that he meant to achieve. According to Mary Nyquist in The Father s Word/Satan s Wrath, â€Å"The text seems here not just to invite, butRead MoreJohn Milton s Paradise Lost1636 Words   |  7 Pagessense to the readers, but would also influence how the readers understood those topics. John Milton’s, Paradise Lost, is a series of twelve Books that tell the story of creation and the world’s first sin, and he relates that to the political distress that was occurring in the seventeenth century and his political agenda in trying to advocate a Parliamentary system versus a monarchy. Throughout his novel, Milton focuses a great deal of time creating a backstory for Satan, who is the protagonist. AdamRead MoreJohn Milton s Paradise Lost1738 Words   |  7 PagesJohn Milton sought to a very ambitious thing with his greatest work, Paradise Lost. He boldly asserted himself to the epic tradition, the most difficult genre. Further, the goal of his writing was perhaps the hardest topic a human being can engage with, the problem of evil. At the risk of being cliche, the old adage, â€Å"If you lose your faith over anything less than the problem of evil, you are simply not thinking.† seems fitting. Milton seems at least, whatever his faults, to understand the weightRead MoreAnalysis Of John Milton s Paradise Lost1442 Words   |  6 Pages(Name) (Instructor) (Course) (Date) Heroism in John Milton’s Paradise Lost There are many definitions of a hero, and establishing the hero in John Milton’s Paradise Lost has been object to scholarly debate. One definition of a hero is that by Aristotle, who defined a hero as a person who is divine and superhuman. However, other definitions encompass the aspect of virtue in heroism. Despite all the definitions for a hero, it remains factual that a hero would be someone that the readers would delightRead MoreAnalysis Of John Milton s Paradise Lost 1071 Words   |  5 Pages Writing AP Exam Essays Advanced Placement English Literature Composition Name Juan Linares Major Work Data Page Paradise Lost Writer/Nationality John Milton/ UK 1608-1674 Theme/Meanings of the work as a whole Disobedience plays a key role in the unfolding of Milton’s poem. Satan disobeys God because God gave him free will, and causes Eve to disobey Adam, to disobey God. Justification of God. Death must happen to the world but because of the Son, DeathRead MoreAnalysis Of John Milton s Paradise Lost 1852 Words   |  8 Pagesnot merely summarize the plot. (2010 AP Literature and Composition) Disobedience and Exile an Analysis of Satan from Milton’s Paradise Lost John Milton’s epic poem, Paradise Lost, has been the subject of criticism and interpretation through many years; these interpretations concur in that Adam and Eve are the sufferers of the poem, and it is their blight to lose Paradise because of their disobedience; however, their exile is merely a plight brought by Satan, and it is he who suffers exile beforeRead MoreJohn Milton s Paradise Lost 1328 Words   |  6 PagesRobert Mezian Professor Mylander English 589 14 November 2016 Paradise Lost Essay In his epic poem titled Paradise Lost, John Milton describes his work as a process to justify â€Å"the ways of God to men†. In terms of the personal and individual, Milton’s main concern was between a man’s relationship and God. With this, comes the very idea of free will itself. One can define free will as the ability and freedom to choose between different possible courses of action. Not only is free will portrayed inRead MoreJohn Milton s Paradise Lost1528 Words   |  7 Pagesfree world. God judges no one and forgives all for his or her sins. God is an honest being. The last statement might not be the case in John Milton’s Paradise Lost. The fall of Adam and Eve is truly a tragic tale. Some suggest that their fall could have been prevented. However, after close examination, one can believe that it might not be that simple in Paradise Lost. God displays some questionable actions in the process that eventually leads to the fall. While not the popular opinion to some, God isRead MoreJohn Milton s Paradise Lost921 Words   |  4 PagesJohn Milton’s Paradise Lost continues the epic tradition developed by the ancient Greek and Roman poets. Composed in exact imitation of its predecessors, the work depicts all characteristics of a traditional epic poem—including the epic hero, a powerful embodiment of societal values. Milton presents his hero in a most unpredictable form: Satan. Despite the unorthodox oddity, the former archangel exhibits the conventions of an epic hero. Milton’s forced perception of Satan as the hero of the poemRead MoreJohn Milton s Paradise Lost1686 Words   |  7 Pagesand bled into the writing it produced. John Milton’s Paradise Lost is no exception to this, as it explores human sexuality and gender roles. It has been argued that when Adam and Eve are described as â€Å"Two of far nobler shape erect and tall,/ Godlike erect† (4.288-289) there is no distinction between the two , and that they are being portrayed, even by Satan, as equal. This is the reader’s first introduction to Eve who, based on these two lines from Paradise Lost, is Adam’s equivalent in power and in

Health risk appraisal Free Essays

1. What areas of information are missing from this appraisal that would be helpful to you as a clinician? Though the appraisal was quite thorough, it did lack appropriate information regarding patient and family medical history (Chowdhury et al., 2002). We will write a custom essay sample on Health risk appraisal or any similar topic only for you Order Now While the patient’s lifestyle has an undisputed influence on any health problems he or she might be experiencing, insight into medical history has the potential to reveal genetic propensities that might weigh heavily on the patient’s health (2002). Also missing from this appraisal form is information regarding medications currently being taken by the patient. This is also useful to the clinician as it gives an idea of previous/existing conditions as well as the possibilities for side-effects, allergies, and interference with the drugs that might be presently prescribed for the patient (Nordenberg, 2000). 2. How can this tool be used to create a plan of care? This tool could be used to create a lifestyle change care-plan. The tool probes a wide variety of life-style areas and has the potential to reveal areas in which the patient has compromised his or her health by making and perpetuating bad lifestyle choices. Dietary assessments can be made and regimens created to improve the patient’s nutrition. Physical activity level is also made very accessible by this tool, and exercise plans can be created and modified for the patient starting with the assessment made using this tool. 3. What areas of the appraisal had you not considered previously in your assessments that you now recognize as being beneficial? The safety issues and the environmental issues were areas I had not previously considered in my assessments. I do see the necessity of these factors now, as decisions made regarding safety and environment can contribute as much to the well-being of a patient as diet and exercise. If, for example, a patient is routinely involved in mixing drinking with driving, then life expectancy will likely be reduced, even in the presence of regular exercise, proper diet, and good family medical history. 4. Would you use this appraisal with all assessments? Because of the nature of the lifestyle questions, which seem to be better suited for certain demographics, I would not use this appraisal with all assessments. If not, which aggregates or situations would you implement it with? I believe that the nature of the lifestyle questions dictate that the appraisal in its entirety is best suited for a healthy young population. The aged and aging might be able to relate to the dietary and safety questions, but will likely not be able to relate to those areas concerning strenuous physical activity. If you do not implement it with all clients, what measures will you include in order not to miss at-risk persons? I will incorporate many of the questions but not all of the sections. For example, the physical activity sections might be modified to accommodate lower levels of strain for geriatric patients. Furthermore, since falling is a hazard for older patients, balancing activities may also be included in that section. The dietary section could also be modified to include some of the areas necessary for geriatric patients, such as increased consumption of protein, calcium, and other minerals that deplete with aging. 5. What two things would you suggest to improve this health risk appraisal tool? In order to improve the tool, I would include measures of such lifestyle areas as stress levels and the patients’ financial capabilities. These too have the potential to increase the risk of illness in patients or to preclude their ability to properly care for their illnesses. 6. How could this tool be adapted to meet the time constraints of the nurse yet be comprehensive at the same time? One way to expedite time in the process of collecting the information would be to distribute the assessment to the patients prior to their meeting with the nurse. This way, the patients will be granted the time to fill it out at their leisure before bringing it in at the time of consultation. 7. How can the nurse use information gained from this appraisal to encourage or motivate others to change their behavior or lifestyle? The point system that the test utilizes has the potential to motivate patients, as higher scores boost morale and lower ones demonstrate that greater efforts would improve the patients’ lives. The breakdown of the test into areas also allows the patient to pinpoint the areas where changes would be appropriate. Therefore, stressing the benefits of behavior and lifestyle change in those areas would also encourage the patient to do what is necessary to get these desirable results. 8. How can the nurse ensure honest responses for the client in answering personal questions? In order to promote honesty, the nurse would ensure the confidentiality of the consultation as well as of the results of the assessment. Meeting in a private area would emphasize this, as would the use of envelopes as containers for the completed questionnaires. The nurse should also formally assure the patient of the confidentiality with which the information provided will be treated, and see to it that all other workers adhere to privacy guidelines. References Chowdury,   M. V. Chongsuvivatwong, A. F. Geater, H. H. Akhter, T. Winn (2002). â€Å"Taking a medical history and using a colour scale during clinical examination of pallor improves   Ã‚  Ã‚   detection of anaemia.† Tropical Medicine International Health 7 (2), 133–139. Nordenberg, T. (2000). â€Å"Make no mistake: medical errors can be deadly serious.† FDA    Consumer Magazine. U.S. Food and Drug Administration. Retrieved on March from   Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚  Ã‚   http://www.fda.gov/fdac/features/2000/500_err.html How to cite Health risk appraisal, Essay examples