Your thoughts on Time Travel

To me, time travel seems ridiculous. If you move faster than the speed of light, all you are doing is delaying the amount of time for things to appear to you. So, essentially, you could see a mirror image of yourself but it wouldn't actually physically be you, it's only a delayed image of what happened before the light got to you. Light doesn't effect matter, so essentially you wouldn't be able to travel back in time.

Good point on the technicalities of it. As I see it, if someone would travel through time, especially in the past, I can easily see someone altering events, and leading to some very disturbing changes or erasing of certain courses in history. More disturbing though, would be the possibility for inadvertantly causing time loops or paradoxes which would do who knows what. And no matter how careful someone is, the more they travel, and the more that join along, they WILL make a bad mistake and change something. And theoretically, if time travel IS possible, then people are out there doing it NOW, because either we have the tech for it now, or in the future. But this means that there would ALWAYS have been time travelers because at whatever point we found the tech for it, we would start traveling throughout all of the past and future.
But I don't think it IS possible, because given what would definitely happen as a result of time travel, I don't think the world would be like it is, or even here at all. I just see too many paradoxes that would do lots of damage.

I agree with SimpleTruth.

Time paradoxes cause to many problems for time travel.

I just had an interesting thought though. Instead of travelling back in time and altering the past just by your presence and creating an infinite loop of paradoxes, maybe you could simply observe the past from a higher dimensional view point. Kinda of like us observing the timeline of a two dimensional world. We wouldn't have to intrude on their timeline but just simply observe it from a higher view point.

Creating the technology to achieve this, well thats where I stop.

A time paradox isn't exactly a dead end is it? If we can fast forward time, or end up in the future, or however it is acheived, wouldn't you be creating a new "zone" or "time" by changing something?

So if we are talking about the reference of a paradox being a kid who goes back in time and kills his mother before he is born, perhaps that just starts a new timeline and he wouldn't be born in that one.

Works for me.

I don't agree with you guys. I'm not probably clever enough to understand it completely, and I even doubt so far anyone did, but I understand time travel, why it is possible and its implications.

First thing is, it is possible. Time is itself relative to all the rest. It also doesn't flow at the same rate for people moving differently. Example of that: two persons going for a round trip around the earth, in opposite directions, if at the same speed, will meet again where they left, but they would have each of them traveled a slightly different amount of time.

I think it is also possible in the past, through what some call "wormholes", or basically the foam-like structures of time/space continuum as it is theorized now.

(I admit I need more research on those myself to understand it more completely...)

Second, the paradoxes that it would generate to travel to the past are discussed a lot, but it seems that most agree now with a theory that wouldn't create problems.

Example: you travel back to a time when your mother lives, but you're not born yet. You kill her. Then? If your mother dies before you're born, you can't be born. But if you are not born, then you can't kill her!! Actually, at the moment you go back in time, you create a sub branch in time flow, the one in which you travel, and it is independant from the one from which you came. So anything that you do there will affect the future of that branch, but not of the other one.

The question still is, if that is possible of course, if you do that, which branch will you return to when you return to the time ytou departed? The one in which your mother died or the one where she lives? My conviction is that you would go back to the one where she lives. If not, you can't be there, because you're not born!

So basically, what you would do by going back in time, is affecting the future of another world, but never yours...

Any comment/help/educ links/... way welcome!

by: Madacc
To me, time travel seems ridiculous. If you move faster than the speed of light, all you are doing is delaying the amount of time for things to appear to you. So, essentially, you could see a mirror image of yourself but it wouldn't actually physically be you, it's only a delayed image of what happened before the light got to you. Light doesn't effect matter, so essentially you wouldn't be able to travel back in time.

You have just touched upon some very interesting ideas, however, I don't think you're seeing the potential that lay hidden within them. This, I believe, is why Time Travel to you seems 'Ridiculous', but to many others, myself included, Time Travel seems anything but 'Ridiculous'. If you'll just hang with me for a bit I'll try and explain why that is and using methods and examples that can be understood without a Degree in Quantum Math/Science/Physics. Hopefully anyway, I might fail completely also, but let's give it a shot anyway...

First let's look at 'Time' in a Dimensional Way as in 'Time-Space'. For example:
I can give you Directions to buried treasure using measurements of 'Space'. Like go north '10 miles', then west '20 miles' and down(dig) '30 miles'.
I can, on the other hand, give you the same Directions to the treasure using measurements of 'Time'. Like go north '1 hour', then west '2 hours' and down(dig) '3 hours'.
Now, by looking at those examples mathematically, and by including 'Your Rate of Movement' equally into each one (for this example we'll use Your Speed of 10mph for simplicity), you should be digging up treasure using either method. In other words:
(Speed * Time = Distance) = (Speed/Distance = Time)
(10mph * 1hr = 10 miles) = (10mph/10 miles = 1 hour)
(10mph * 2hr = 20 miles) = (10mph/20 miles = 2 hours)
and so on and so forth.....Simple right?? Just keep this in mind for now, and we'll tie it in later with some other stuff for the Big Picture!

Next, let's look at the Matter to Energy/Energy to Matter thing. Matter to Energy conversion isn't anything new to most people. It's most common example that stands out in peoples minds is of course Atomic Energy and Nuclear Weapons. Also the well known equation of 'E=MC^2' (2 is power of 2, don't know how to make superscripts here) or 'E=MxCxC' or 'Energy=Mass X Speed of Light Squared'. If you were to plug in the numbers you'd come up with, for example: 1kg of matter, any matter, we can get out 9x10^16 joules of energy. Or 90,000,000,000,000,000 joules, which is a lot of Energy!!

The reverse of this, in one example experiment is done by taking a couple of 'Photons' or 'Particles of Light', spinning them, and smashing them together, resulting in Exotic Matter being formed. The important thing to keep in mind here is that the 'Matter' which is made has a Mass Greater than the original 'Photons' themselves. The Extra or Added Energy to Mass conversion therefore comes from the 'Kinetic Energy' from the Spinning, or Movement of the 'Photon', which gets Added in along with the Energy/Mass of the 'Photon' Particles. Still with me, right? That is a very simple version of the process, but for this post the general idea is all I'm really going for so we should be alright.

Now, let's have some fun using these concepts in a simple thought experiment about Faster than Light Travel. One more thing to add in here is that within 'Special Relativity' there are Two Principles that basically make up the foundation.
#1: The Laws of Physics are the Same for All 'Frames' of Reference.
#2: The Speed of Light, within a Vacuum, is a Constant at 300,000,000 meters per second(186,300 miles per second).

Here is an example that will hopefully make all this a little more understandable:
Let us assume that we have three Space ships assembled at a given point upon the surface of the Earth (or at a given pint in Space). For the purpose of this analogy we will assume that the ships are capable of any desired degree of acceleration. We will dispatch two of these ships into Space, flying side by side in a given direction. We will launch the remaining craft in the opposite direction in Space.

"We have an observer upon each of the three craft and a fourth observer who remains at the point from which they departed. Let us call the ships which departed together as A and B, the ship which is moving in the opposite direction as C, and the observer at the starting point as D. When we have accelerated all three of the ships to a velocity equal to one half that of light (with respect to the starting point) we pause to determine what changes, if any, have taken place. To the observer at the starting point D, the three ships have become slightly shorter in the direction of their motion, and have gained a small amount of 'mass,' but are otherwise unchanged. The observer upon the ship C, however, discovers that while he and his own ship appear to be unchanged, the ships A and B have lost all dimension in the line of motion, because they have reached the velocity C with respect to his reference point. They have ceased to exist as matter and have entered the plane of energy. The two observers upon the ships A and B also note that C has ceased to exist as a material object, but when they examine themselves and each other, they find that no change whatever has occurred to them or to their ships since they are all upon exactly the same energy level and no differential exists between them. This can get even more wild but for now we can stop it here.

Here is another example of 'Relativity' and how there is a Fundamental Connection between 'The Observer' and 'The Observed'. That concept there is Very Important and Very Interesting to think about. It is also one of the major points behind me typing this Really Long Post BTW!!' Anyway, here is example #2:

Mary, a 30 year old NASA astronaut, blasts off from Cape Canaveral in her very high speed rocket in the year 2010 on a 10 year mission to a nearby star. After a short time she is traveling at 270,000 km per second, that is, 90% of the speed of light. To Mary everything looks normal in her rocket; the clock seems normal and time passes for her the way it did back on Earth. Her identical twin sister, Susan, is a NASA ground controller for the mission. Ten years pass on Earth before the rocket returns and when it does something is immediately apparent; while the Earth-bound Susan has aged 10 years, her high-flying "twin" sister has only aged 5 years! How can this be? Well, again we are back to "moving clocks run slow". At 90% of the speed of light time slows down to about half of that relative to someone who is stationary. So while 10 years have passed for Susan only 5 years have passed for Mary because her "clock" was running at half the speed of those on Earth. This is called the twin paradox. Remember that while Mary has only aged 5 years she still felt that time was passing normally; this is not a way of living longer! Not only was her clock running slow as far as a ground based observer is concerned, but her time was running slow.

Now, wasn't that fun & simple enough to understand?!?!? I hope so, cause that was a lot of typing!! I also hope I didn't mess anything up too bad. I'll be proof reading it a couple times just in case...