The Near Impossibility of Time Travel

Oh yes, a great science fiction plot object.  My father's favorite story line.  The "Time Travel" gimmick that entertains everyone from the Geek to the casual reader. I am a big viewer of the "Nerd Channels" on television.  I like to watch the Science Channel and Discovery channel quite regularly.  I've given up on TLC as it has just become the decorator channel.  Although Discovery seems to be the Alaska channel now, but I digress... I have always been interested in science.  No, not the junk science so many practice now days with their "assume that..." theories and such, and claiming them as facts.  I am talking about pure science.  The kind of real science politics, government funding and Al Gore can't pollute into a false religion. Don't get me wrong, TV is not my only source of information.  I love to read as well, and have read more than just fiction.  While I don't claim the mental fitness of Einstein, I do grasp the concept of relativity and for the most part, it makes sense to me. Many times, when I see scientific and experimental concepts discussed about time travel, I only hear the theoretical and Earth-centric aspect of it being spoken of.  Things such as worm-holes, warping, and folding space come into the conversation.  These theories may have scientific merit, but they don't have practical understanding.  I frequently see scientists in the world that concentrate on their fields exclusively, and frankly, are completely ignorant of many other scientific fields of study.  If there's one thing I have learned as a computer professional, it's that knowing hardware, software, and all technologies relating to the industry gives an edge to the quality of work offered as a programmer.  Those that only understand programming and have no idea how a CPU and its relating electronics work together will always be at a disadvantage and missing a very important point of view.  Science is the same way.  You may be nuclear physicist, but maybe, just maybe, knowing a bit about astronomy and geology might just help you in your field. Back to time travel.  I hear a lot about the fundamentals of relativity being discussed in relation to time travel theories,  but I never ever hear the practical and obvious problems relativity brings to the issue.  Only the deepest theories are discussed, but never the problems they cause. Let me lay it down, so to speak, for everyone to understand.  Let's say someone figures out how to travel through time and makes a "Mr. TimeTravel" or "flux capacitor" device.  Yay for him/her!  Guess, what?  It still will be unusable.  They have only conquered the tip of the iceberg.  How?  The universe is not like a Hollywood movie, nor is the Earth sitting stationary in space.  Bending some laws to achieve time travel does not eliminate other laws.  

[caption id="" align="alignright" width="300" caption="Image via Wikipedia"][/caption]

Consider for a moment that nothing in the universe is sitting still.  In fact, most, if not all of it is moving quite fast, blazingly fast.  You think you are sitting still on Earth reading this, but in reality this is happening:

• You are traveling (if sitting on the equator) 1000 miles per hour as the earth rotates on its axis.  You have this great spinning force wanting to fling you off into space, but the Eath's gravity keeps you firmly in your chair.
• The Earth is orbiting the Sun, a simple star called "Sol", at approximately 18.5 miles per second.  Pretty darn fast in and of itself!  The Earth should be flung out into space, but it and the Sun's gravity keeps it comfortably in a stable orbit.
• The Sun, "Sol", orbits the Milky Way Galaxy's center at approximately 450,000 miles per hour, with a slight oscillation through the galactic plane.
• The Milky Way Galaxy is (by most scientific estimates) traveling through space at approximately 1.3 million miles per hour.

OK, you now have this fancy-schmancy "Mr. TimeTravel" device or a flux capacitor, and you want to do some time traveling.  GREAT!  Now you need to solve the problems of distance.  If you want to appear even five minutes into the past, then you had better be wearing a space suit and have a REALLY fast space ship, because you aren't anywhere near the Earth when you arrive.  You will appear at precisley the point where you left the Earth at that particular time.  You will also have the relative inertia of all of that speed from the Earth's rotation, the Earth's orbit, the Sun's orbit, and the Milky Way's speed all at once without the gravity to govern it.  In a split second after you arrive, you will be nowhere near where the Earth is going to be even in just five minutes worth of time travel. Where you appear all depends on what direction you were heading when you left, and what direction the Earth was heading.  There is a chance you might end up inside the Earth itself or inside the moon or other object, if not out in space.  There's no way you are landing on the Earth after you zap to another time. So time travel may sound cool, romantic, and a great way to write a story.  I don't think mankind will ever be able to actually experience it.  There's just too much going against you.