DISCLAIMER: Time travel is an entirely unproven technology. Most any arguments (either for or against it) can be refuted to a certain degree, because there is no precedence and therefore no evidence. What is presented here is a number of theories on the topic, and a few other issues related to it, and all of them are pure speculation. If any of these ideas are yours and I didnít credit you, rest assured that no money is being made from this and I make no claims to any of the material here. The intent of this is to pose questions to the reader, and to promote thinking and speculation about an interesting (but purely hypothetical) topic.
DEFINITION OF TIME TRAVEL:
In order to discuss any topic, you must first define it also define what issues lie in the realm of discussion. Normal movement as we all know it is defined as distance covered in a given period of time, or D/T. This means that velocity is measured by distance with respect to time. Time travel, however, would be defined as the amount of time traveled in a given time, or time with respect to time (T1/T2). This would theoretically allow for ìtime velocityî to be either positive or negative, meaning one could travel backwards or forwards through time. If for instance, someone were traveling at ñ5 seconds per second, he would end up five seconds in the past for every second he was traveling through time, and at +5 seconds/second he would travel forwards five seconds every second.
THE THEORIES:
1-TO-1 TIME TRAVEL:
The most basic form of time travel is going on all throughout the universe at this very moment, and hopefully will continue for quite some time. We are all traveling forward at the rate of one second per second, so all we have to do is waitÖ
MATTER TRANSPORTATION:
Another basic theory for time travel is one that is being researched
even now, which is the idea of matter transportation. Already scientists
are discovering how to transport single atoms, and light, and while this
is not time travel as most people think of it, it does have some merit
if thought of from the right point of view.
Matter transportation would effectively be time travel if thought of
in this respect: Consider a man who begins walking from point A to
point B, and a second man who is instantly transported from A to B.
From the first manís perspective, because the second man moved so
quickly, the second man effectively gained the time that would have been
taken up had he walked the path from A to B as the first man had.
This may not meet the loose definition above of experiencing more or fewer
seconds in a given second, but it does present an interesting idea that
is already being explored scientifically
WORM HOLES:
Another theory for time travel would involve the use of worm holes. A worm hole is an area of space that when entered, acts as a tunnel that will deposit a traveler in a wholly different area of space. The distance covered when traveling through a wormhole could theoretically be any distance at all, from the smallest micrometer to from here to the edge of the universe. This idea is akin matter transportation because of the covering of distance in so little time, but there are a few twists that can be thrown in to make a slightly different time travel theory. What if, for example, one end of this wormhole was accelerated to the speed of light, so that it was experiencing far more seconds for each second that the first end experienced. This could theoretically send anyone who traveled into the wormhole into the future.
THE PROBLEMS:
There are numerous problems that arise when dealing with ideas
of time travel. Before even mentioning such things as paradoxes,
there are much simpler and easier to understand difficulties with time
travel.
The first is perhaps the simplest, one that physicists are quire familiar
with because it one of the fundamental laws of the universe: all
matter and energy in the universe is conserved. Therefore, if you
travel back in time, you are adding matter to a universe that is already
full. What effect this would have is unknown, but it would undoubtedly
upset the balance to have identical molecules in the same universe.
Secondly, the speed of light is a major issue. Some would
contend that traveling at or near the speed of light would cause time travel,
but the questions here are numerous. What energy in what form could
be used to generate the power to get to the speed of light? How would
mass and density of things traveling so fast or things around them be affected?
Would the surroundings of the time traveler appear to be moving incredibly
slowly because he is going so much faster than they are, or would they
move incredibly quickly past him like they do in a race car? Would
someone moving at the speed of light be able to see at all? Would
the light be moving too slowly to be of any use to his eyes? Would
he be moving so fast that any collision with even the tiniest of particles
would create massive damage? These are all questions to consider
when dealing with faster than light travel.
Even so, letís put them all aside for a moment and think
what would happen if we could go so fast, and we didnít all die
in some terrible faster-than-light explosion or fire or collision.
Letís say we can go that fast, and we do. What then?
The problem that we are quickly faced with is that time (much like all
other manmade quantities) is entirely relative. A second is only
a second because we say it is a second, much like an inch or centimeter
or a pound or an ounce are only so big because we say so. If the
men who came up with the inch had tacked on a centimeter, we all would
grow up thinking that an inch was a little bit bigger than it is now.
What if he had tacked on a micrometer? Or a picometer? By the
same token, time could get infinitely small, and perhaps never reach a
limit. This is the basis for the argument that ìtime doesnít
exist.î How could a machine measure time in any other way than
how we program it, and how could we program it any other way than we perceive
it? Even if we could get a computer to recognize millions of fractions
in a second, what good would it do? What time zone would the clock
be in? There will always be a smaller fraction. Time is indeed
one thing in the universe that has and always will exist, and yet will
never exist.
That brings me to the next point: PARADOXES. Assuming
that time was measurable, and assuming we had a way to transverse it, how
could we ever do anything without risking a paradox. Paradox, by
definition, is something that canít exist. A causeless event.
This is what would arise from any travel to the past. Say for instance
you wake up one day and flick on your bathroom light. Then one minute
later, you travel back in time two minute, donít make contact with
anybody, but you turn the light on before you originally turned it on.
Now we have a paradox. Now the first YOU will walk into the bathroom
and not flick the light on, because it was already on from the second YOU.
Therefore, the first YOU will have no reason to travel back in time and
turn the light on. However, if the first YOU does not travel back
in time and turn the light off, then the second YOU will never exist.
Paradox. Even if the first YOU traveled on some other matter, the
second YOU will still never be created and will therefore not be able to
turn that light switch on. A third YOU may be created, perhaps one
that turns the television on, but that will merely create a whole other
set of difficulties. Causeless event. Paradox.
There is a rule which has been around in the world of physics
for as long as there has been a world of physics, and that is that nature
abhors a vacuum. Nature does not allow for vacuums to occur without
some interference from mankind. There is a theory that states this
may be true for Paradoxes. Perhaps nature will not allow for a paradox
to occur. Maybe it has a kind of ìself-preservationî
instinct that would not even give rise to the possibility of paradox.
This implies one of two things: Either time travel is inherently
impossible because it allows for the development of paradoxes, or that
something will always happen through the course of time to stop a paradox
from forming. This latter theory would suggest that time is not constant
as many believe, and that it can be altered by time travelers who themselves
wonít be effected by the time travel. They may or may not
retain memory of the prior timeline, but they would be allowed to alter
the future without destroying themselves as YOU ONE did to YOU TWO.
Letís take another leap now, and allow ourselves to believe
in speed of light travel, wormholes, and paradoxes and think what would
happen if the above scenario happened. YOU ONE walks in, flips the
light, then travels back in time. At this point, YOU ONE becomes
YOU TWO, and sneaks around the house to flip on the switch before YOU ONE
sees him. At what point does the paradox occur? Is it at the
point that YOU ONE decides not to travel back in time? Or is when
he first sees that the light is already on? Or is it the instant
that YOU TWO touches the light switch? Or is it the moment that YOU
TWO decides to touch the light switch? Or is it the very instant
that YOU ONE decides to travel back in time? The answer is, of course,
that no one knows. If the last were true, then weíd all be
in trouble because by that logic as soon as anyone thinks about traveling
back in time they create a paradox.
When a paradox is created, if it can be, there are a few theories
on what exactly would happen. The first two have already been discussed.
Either some form of intervention would occur that would stop the paradox
from forming, or some sort of alternate universe would be created and the
time travelerís memory would not be influenced by another version
of himself.
But, what if neither of those two things happened? What
if a paradox actually occurred unresolved? Would the space-time continuum
unravel? Would the universe destroy itself? If so, in either
case, how long would it take and what would it be like to witness?
These are perhaps the most unanswerable of any questions yet posed here,
because by definition of a paradox they call for a set of impossible circumstances.
One entirely un-researched theory that a friend of mine came
up with addresses the issue of what happens when a paradox occurs.
Perhaps a paradox, when unresolved, would cause the complete collapse of
the universe. This is nothing new, but there is more to it than that.
Nothing can destroy matter; not heat, not cold, not any extreme known to
man. Therefore, by holding to the laws we know to be true, in the
event of the universe collapsing, all matter and energy would be conserved.
What my friend added is, what if that was the cause of the big bang?
What if the universe pulled itself to the center and spit itself back out
again? The universe would then grow and expand once more, with all
the matter and energy reset to the way it was at the Big Bang. Because
everything was reset and conserved, every development in the universe would
happen all over again. We may have had thousands of Big Bangs already,
and someone in the future will travel back in time and cause it at some
point in the past. They always will, they have to, because the universe
is always the same.
Of course, this is open to all sorts of arguments. For
one thing there is no reason why everything would happen the same way each
time, unless nature is acting to preserve itself. If things did not
happen the exact same way, then the traveler would never go back in time
to cause the Big Bang. We then have a paradox within a paradox.
The universe, in order to compensate for the original paradox, resets itself
with the Big Bang. Then, in order to insure that there is no other
paradox, it causes everything to happen just as it did, using a paradox
to avert a paradox. It sounds paradoxical, doesnít t?
The final touch to this is a point made earlier that at what
point does the paradox occur? If it were at the instant that the
paradox was first conceived, then that would be the Big Bang, in which
the universe would be in a perpetual state of Big Bang, like a paint can
in a paint mixer.
CONCLUSION:
Time is a mystery. It always has been, and for the foreseeable future, it always will be. However, there are technologies at work now that may make a few steps toward understanding this phenomenon that we call Time. Chriogenic technologies may someday allow for a few privileged individuals to be placed in a frozen sleep long enough to awake in a new era of civilization. If matter transportation technologies progress, we may someday find ourselves traveling across the world or even the solar system in the blink of an eye, doing what some people would call ìpresent time traveling.î For now though, all we can do is continue as we have been since whatever it was that caused the Big Bang. Think about that before you fall asleep tonightÖwait, you better not.
SOURCES:
HYPERLINK http://www.timetravelinstitue.com/ http://www.timetravelinstitue.com/
HYPERLINK http://timetravel.com/ http://timetravel.com/
Nathan Nasuta
Jakob Erickson
Time and his friend the Universe