Υλικό που μπορεί να χρησιμοποιηθεί στην εργασία Ι

Εισαγωγή

Από το άρθρο που υπάρχει στο site:
http://science.howstuffworks.com/time-travel.htm
καθώς και τα στοιχεία που εντοπίζονται στο site: http://www.pbs.org/wgbh/nova/time/
"Time is nature's way to keep everything from happening at once." (John Wheeler)

There may be no other concept that captures the imagination more than the idea of time travel -- the ability to travel to any point in the past or future. What could be cooler? You could jump into your time machine to go back and see major events in history and talk to the people who were there! Who would you travel back to see? Julius Caesar? Leonardo da Vinci? You could go back and meet yourself at an earlier age, go forward and see how you look in the future... It's these possibilities that have made time travel the subject of so many science fiction books and movies.
Ideas of time travel have existed for centuries, but when Albert Einstein released his theory of special relativity, he laid the foundation for the theoretical possibility of time travel.

Χρήσιμα στοιχεία για τον ορισμό του ΧΡΟΝΟΥ
Time is also defined as being the fourth dimension of our universe. The other three dimensions are of space, including up-down, left-right and backward-forward. Time cannot exist without space, and likewise, space cannot exist without time. This interconnected relationship of time and space is called the spacetime continuum, which means that any event that occurs in the universe has to involve both space and time.

Ποιες προοπτικές ανοίγονται με τη θεωρία σχετικότητας του Einstein:
According to Einstein's theory of special relativity, time slows as an object approaches the speed of light. This leads many scientists to believe that traveling faster than the speed of light could open up the possibility of time travel to the past as well as to the future. The problem is that the speed of light is believed to be the highest speed at which something can travel, so it is unlikely that we will be able to travel into the past. As an object nears the speed of light, its relativistic mass increases until, at the speed of light, it becomes infinite. Accelerating an infinite mass any faster than that is impossible, or at least it seems to be right now.

Έχετε δει την ταινία
Back to the Future?
The spacetime continuum was frequently mentioned in the movie "Back to the Future." Doc Brown and Marty travel from 1985 to 1955 in a DeLorean that has been converted into a time machine.
What Marty and the Doc soon realize is that interactions with Marty's parents in 1955 threaten to unravel the fabric of the spacetime continuum. Check out more information about DeLorean DMC-12.

Στη ζωή δεν θα χρησιμοποιηθούν μηχανές του χρόνου, αλλά φυσικά φαινόμενα (blackholes, wormholes και cosmic strings). Οι μηχανές του χρόνου συνδέονται με την προσπάθεια του ανθρώπου να συσχετίσει χρόνο με χώρο και να αναπαραστήσει την πορεία σε άλλες χρονικές βαθμίδες ως τοπική πορεία προς άλλο σημείο, ενώ η έννοια του χρόνου λειτουργεί διαφορετικά.

Σκεφτείτε:
Ηow popular media portrays time travel in science fiction literature and movies, such as "Back to the Future," "Terminator I" and "II," "Contact," and "Star Trek." Why you think time travel is such an appealing subject?

Διαβάστε σχετικά με την παρακάτω έννοια: Time Paradox ή grandfather paradox

One of the complications with time travel is an idea known as the grandfather paradox. Stated simply, it says that if you traveled to the past and accidentally killed your grandfather before your parents are conceived, there would be no way for you to be born. Therefore, you would not exist to travel back in time in the first place. So how could you have killed your grandfather?
Στη συνέχεια αναπτύξτε το δικό σας σχέδιο: Develop your own scenario where you go back in time and change something. List the many ways you think your change might affect a future timeline.

Bibliography
Hawking, Stephen W. "A Brief History of Time: From the Big Bang to Black Holes." New York: Bantam Books, 1988.Describes what we know of the universe and includes discussions on space and time and the direction of time.
Nahin, Paul J. Time Machines: "Time Travel in Physics, Metaphysics, and Science Fiction." New York: Springer-Verlag, 1999.Explores time and space, time travel, and some of the paradoxes involved in time travel. The author examines the science and science fiction of many popular ideas.
Sagan, Carl. "Contact." New York: Simon and Schuster, 1985.This is a fictional account of looking for evidence of life other than on Earth and describes the physics involved in making such a journey.
NOVA Online - Time Travelhttp://www.pbs.org/wgbh/nova/time/Includes text and audio from Carl Sagan about subjects ranging from wormholes to the nature of time, an excerpt from a book by an author who claims time travel is possible, a dictionary of words and concepts scientists use when discussing time travel, and an interactive game that encourages players to "think like Einstein."
Everything You Always Wanted to Know About Time Travel

http://www.biols.susx.ac.uk/home/John_Gribbin/Time_Travel.html

Provides background information on time and the universe and the possibility of time travel.
Time Travel: Fact or Fiction? Describes the problems and paradoxes of time travel. http://math.ucr.edu/home/baez/physics/Relativity/GR/time_travel.html
http://www.crystalinks.com/timetravel.html
http://www.poiein.gr/archives/2269/index.html#more-2269