Have you ever had an idea or thought which suddently popped into your head which meshed together two other unrelated ideas? Specifically, what if ghosts aren't really the spirit incarnation of our former selves (as some believe) but are in fact ourselves but in a different time?
Most people who watch or read science fiction stories will be familiar with the concept of multiple times. For those of you not familiar with this concept I will attempt to give a brief description.
Imagine a horizontal line representing time as we know it. Choose a point somewhere in the middle of this line. Everything to the left of that point represents the past, everything to the right of that point is the future and the point itself is present time. Currently, time as we know it flows from left to right and we cannot go back in time.
Now imagine a line which intersects the first line at a slight angle. This line represents a new "time". It runs on a similar course to our time but diverges and goes its own way. This line has its own history which is depedent upon what events are chosen within its confines just as our history is determined by the events we choose.
Now imagine that our time is intersected by an infinite number of lines, each representing a new time for its inhabitants. Stephen Hawking calls it the Sum over Histories and this is what this picture of a line being intersected by an infinite number of lines represents. It's not that there is one history or time line but an infinite number of historys. Put another way (and to paraphrase the esteemed Professor Hawking), there is not one just one possibility for a history but every possibility.
This is the point where you take a deep breath to ponder what has just been said. Let me give you an example to hopefully make this concept more clear. We all know that in our time Germany lost the war. However, suppose for a moment that instead of halting his Panzer army on the outskirts of Dunkirk and allowing the British troops trapped therein to escape, Hitler instead ordered his generals to take the city and all the troops therein. The loss of such a large portion of its standing army would almost certainly have crippled Britains war efforts in the Middle East and North Africa and allowed the German forces to take control of the Mediterranean.
Imagine if the above event had gone the other way. Imagine if the German forces did capture Dunkirk with the British troops still inside. How do you think World War II would have turned out?
This is what is meant when it is said that from any point in history there is not just one path to the future but every possible path to the future. The future is determined by what happens in the past. So what does this have to do with ghosts? Simple. What people claim to see are relatives and others not as apparitions but as they exist in another time.
Remember back to your own history and find an event which could have changed your life depending on what action or decision you took. What if, in addition to the course you have already taken, there is another history in which you took a different path. Maybe you studied harder for a particular test, got a better grade and went to Harvard instead of some other school. Would things still be the same for you?
This is the point I'm trying to make. Maybe when people claim to see a ghost of a Confederate soldier on a former Civil War battlefield what they are really seeing is that person as they are in their time. Their time, to them, is the present while what we are seeing is our past.
You'll note that I never said that the times would run in conjunction with one another. I have merely said that there could be multiple histories for the same event. That is why we see things from our past. It's time running at a different rate than our own time.
There are two other matters which would need to be explained for this to be true. Why are we seeing these "times" at all and why do we see our past and not our future?
To answer the first part, the reason we see these past events could be a temporary breakdown in the structure of the space-time continuum (ok Trekkies, dig in). Assuming that space is like a sheet of fabric which is warped by the mass of an object within it (which has been confirmed), these events that we see could be tears in the fabric between our time and their time. Thus, for a few brief moments in time (our time) we see an event from our past.
So why doesn't the event continue on but instead stops at a certain point? Because their time and our time are moving at two different speeds. The two times cannot merge into one time. To use an example, imagine two cars travelling in the same direction down a road but a different speeds. One car is travelling at fifty miles per hour and another at sixty miles per hour. The car speeding along at sixty miles per hour will overtake the slower car. However, for a brief moment, the passengers in the faster car will be able to glimpse the passengers in the slower moving car. This is the same reason why our time and their time can't become one time. We are travelling at different speeds.
To answer the second question as to why we see our past and not our future, if we haven't experienced our future how can it become our past? Since our future is dependent upon the actions we take now, we won't or can't know what the future will be like. Thus, we have no knowledge of our past.
Choose to believe what you want. I'm just giving you another idea to ponder regarding the concept of ghosts. Maybe they truly are the spiritual incarnation of ourselves though so far science has concluded that such spirits do not exist and cannot exist. Therefore, it is conceivable that ghosts are not spirits but our past revisited.