by AnonYMous
Well obviously, you told me where to meet you but not when to meet you.
That is right, you could be very excited to see me and show up today, while I could arrive tomorrow, or next year or in a million years. You need a time coordinate to actually meet me in any specific place in the universe. So to actually meet without assuming anything, you will need to know four things: 34th street, 5th avenue, 50th floor, and the time, say tomorrow at 3pm. Humans often don't think of time as a dimension because they think of time as existing only in the now. Yet, in relativity and mathematics, time is not treated this way. Like any of the three spatial dimensions, time stretches into what you call the future and the past. Just as space stretches in all directions and you are in one location of it, so time stretches in all directions and you are experiencing one location, one coordinate in time.
I understand what you are saying, but this has not cleared up the twins situation for me.
Ok, here is the main point. Most humans believed, and still do, that we all move through space freely, but we all move through time in exactly the same way. For instance, it is obvious that you move at different rates of speed in space. I could speed up and move faster than you, or you could speed up and move faster than me. Yet through time we all move at the same speed, together, we always share the same time. However, if you think about it, since space and time are intertwined in space-time, if we move through space at different rates, we must also move through time at different rates.
--At this point, he stood up, and walked to the window. I didn't say anything as I was trying to visualize what he was saying. The power had not been restored and it was getting darker. He pulled back the drapes further and lifted the window up half way. He stuck his head out and looked around. He then walked back to the kitchen and got another bottle of juice. I had the thought of getting up to look for some candles, when he pulled from his pocket what looked like a small round flashlight and put it on the table. It turned on seemingly by itself and gave off a soft glow that illuminated the entire apartment. The light was very natural and did not seem to radiate from the device itself, in that it was not much brighter near the device than it was in the rest of the room. If I did not see the contraption, I would think I had at least twenty candles spaced around my apartment. He took a big gulp of juice and continued.
When you move through space you also move through time, so the speed at which you move through space, effects the speed at which you move through time. When you accelerate through space, you actually move slower through time. As the twin accelerates away from earth, it would appear to someone on earth that time slows down in his spaceship, if he had a clock, it would appear to tick slower than clocks on earth. To the twin in the space ship, everything seems normal. Though he leaves for what seems to him as only a few minutes, hundreds of years have passed on earth. Understand that the accelerating twin doesn't perceive time moving slower, nothing changes in his personal observation of time. Humans all perceive the passing of time in a similar way, no matter how fast they move through it. So there are two different things here: Your perception of time flowing by, and your actual movement through time coordinates relative to others movement through time coordinates.
So even though we both feel the flow of time equally, we don't necessarily move through time equally.
Correct, you can be walking on a street, or walking inside a flying airplane; if you aren’t looking out the airplane window, you will feel as if you are moving at the same speed in both situations. You need to think of time in a similar fashion. Biologically, you experience the flow of time the same way other humans do, regardless of how fast you are traveling. But you will experience this flow of time at different coordinates in time. Both twins are experiencing time in the same way, one in a space ship and one on earth. However, because the twin in the spaceship is moving so quickly, he moves through time much more slowly, he experiences very different coordinates in time. The illusion your senses give you is that everyone is experiencing time at the same coordinate, and they are not.
But I know that these differences in time only manifest at very high speeds, near the speed of light.
They manifest all the time, but your speed on earth is not nearly fast enough for you to notice. Speeds on earth are so similar that you feel like you are all in the same boat. The phenomenon that scientists call time dilation, the slowing of time, which occurs when you accelerate, is only obvious at very high speeds near the speed of light. The closer to the speed of light, the slower the time. Since everything on earth moves so slowly relative to the speed of light, which is a speedy 186,000 miles per second, you do not notice it. The differences are minute and your mind will create a seamless version of events to avoid confusion. To notice the difference at earth speeds, you would need to use clocks that measure in milliseconds. You have these clocks now, and your scientists have proven all of this. When you check a clock in orbit in space, where it is traveling slightly faster than a clock on earth, the two clocks will show a small but significant discrepancy. Things traveling even slightly faster than you, like satellites, have their clocks tick slower than clocks on earth. This technology is critical in your global positioning systems. GPS positions you in space and time, but without the mathematics of relativity to account for the time discrepancy between your time and the satellite's time, your GPS systems would go askew very quickly. Adjustments are constantly being made to GPS calculations to make up for the difference of the time on satellites and your own time on earth.
I have read about time dilation, though the cause of it was confusing. I know that this is a way one could travel to distant stars and galaxies quickly.
Yes, time dilation allows interstellar travel without any extra dimensions or wormholes. If a spaceship traveling near the speed of light travels to a star that is one hundred light-years away, it will seem to take one hundred light years for the spaceship to reach the star to people on earth. To the people on the spaceship however, it will seem like a very short time, maybe a few days or a few months, depending on how close to the speed of light the ship is traveling. As they move faster in space, they would move slower in time compared to people on earth. If the people on earth could somehow look into the spaceship, the people within the space ship will seem to be moving in slow motion. If somehow, the spaceship flew at the speed of light and you could observe it, the people inside the ship would appear not to move at all, their time would stop, their clocks would not tick, they would never age.
I guess I understand what you are saying about relativity, and why you claim that you can travel forward into my future. But can you travel forward into your own future to see what will happen to you?
Physically traveling forward into your own future is more complicated than humans tend to imagine. Remember that you are already there. So you run into a physical law, the law of conservation of energy. The law basically states that in any system, things can change states, but nothing is created or destroyed. Therefore, if you just instantly appear in the future, you would need to remove your future self, and replace your future self with your current self. This could be very messy and your future self would not appreciate being removed.
Could I create a machine that could immediately teleport me to the future, thus removing me from this time to make up for adding me to another?
Good, now you are seeing time in a more complete way. But you won’t get the result you desire by using such a machine. Remember the old saying, "wherever you go, there you are". So if you removed yourself from the world, and magically appeared fifty years into the future, then you will have disappeared for those fifty years. When you look back over the fifty years you jumped over, there is no you whose life you can look back on, because you disappeared fifty years ago. You didn't jump into your future, you simply jumped into your world's future.
Yes, I suppose that wasn't a very good question.
It is hard for humans to accurately visualize time, so these mistakes happen often. Though there i
s a way you could do what you propose, to gain knowledge about your life in the future, but it involves another step. You would need to make a clone of yourself. Then send the real you into the future in a teleporter, or just in the traditional way, by flying around at near the speed of light. When you get back to earth it will be many years later, and you could visit your clone and see how its life turned out. Then that older and wiser clone-you could give the still young real-you personal advice on how to live life. Now you would have the choice of living in the future with this new knowledge, or going back in time, knowing what will happen to you and avoiding the mistakes your clone made.
--I was going to ask about how you could travel back in time, but I was a bit confused by this last explanation and did not want to pursue it any further. After a moment he continued.
An easier solution, instead of physically traveling into any future, would be to simply gather information from the future while staying where you so rightly belong, in the present.
You mean like a psychic who claims to see the future. They aren't actually there but they claim to know what will happen?
Yes, that's right. When you look up at the moon, you are receiving information in the form of light from the moon. You see the moon, but you are not there, you are on earth. You could travel to the moon, but it's a lot easier to just look at it.
But can you really get information from the future, when the future hasn't happened yet?
The future has happened, the future already exists, that is the point of the whole theory of relativity, time-is-a-dimension conversation we just had. I know this is a very difficult concept for humans to accept. Nevertheless, what you call time past and time future, exist. In relativity there is no mathematical difference between time at any point. A point in time is just a coordinate, like a point in space. The future already exists, as does the past. Your understanding of time is based on observing only one coordinate of time, the present. Because you can only observe the present, you tend to believe that the other coordinates of time do not exist.
But I can also observe the past by remembering what happened to me.
No, you can think of the past, in other words use your imagination to recreate an experience you had, to relive it in you mind, but you are still doing that thinking in the now. Your attention may not be on the present, but you always experience in the present. You can imagine the future too, but you are doing the imagining in the present, at this moment. Again, no matter where you go, there you are. No matter what time you are imagining, past or future, you are thinking now. Humans spend most of their time regretting the past or dreaming about the future, but both the past and future are figments of your imagination in the present. The only thing you are capable of actually observing is your current coordinate in time.
Fine, perhaps I am not actually experiencing the past, I am just recalling it with my mind, but I certainly don't sense that there is some expansive future time already set in front of me that I simply haven't experience yet. After all, the future is not set in stone, don't we change the future with our actions?
What time is it and where are you?
It is 6pm and I am in my apartment.
You understand that time and space are dimensions in the universe correct?
Yes.
Yet you do not believe any time other than the current one exists. Do you have the same sense about the space that is beyond this apartment?
What do you mean?
Well, do you perceive that there is space everywhere, or is there only space where you are experiencing it currently, in your apartment? You see your ceiling, yet you do not see the stars beyond it, do you believe they exist?
Well that is pretty obvious.
Just as there is space everywhere but you currently only see your apartment, there is time everywhere, but you can only see this one moment of it. Again, Einstein proved that there is no special place in the universe, for instance your apartment. There is also no special time, for instance 6pm on Thursday. Just because you are here, doesn't mean no other place in the universe exists, just because you are at this time, doesn't mean no other time exists. All time exists, past and future.
I can understand this logically, and this may be what science states. But it is not something I feel. I feel that I do influence my future. And what of fate and free will, if the future already exists?
Throughout human history there has been a debate as to whether all of time already exists, or whether only the present moment exists. The bias was of course towards the idea that there is no time but the present, and you create the future with your free willed actions.
Yes, I certainly feel I am in control of my future. At least to some extent.
It is very possible for you to feel that you are creating your own future, when in fact you are simply approaching the event horizon of your consciousness. You could say your event horizon is the moment when you are consciously aware of something. In the case of space, it is where you first see a thing, where it first enters your field of vision. In the case of time, it is the present, since you do not actually observe the future. This creates some confusion in your understanding of time. Let me give you an example of a life form that is just as confused about the nature of space as you are about time. There are actually plenty of such creatures on earth, but I will use a more dramatic example from a distant place. Ah, this juice is making me warm.
On a Distant Planet
--He had just finished the bottle. Instead of being pale he now looked quite red. He stood up and went to get another bottle of juice. He was wearing a dark blue sport coat, Penguin brand I believe. When he returned to his chair he unbuttoned the coat. When he did, I noticed he was wearing a green tee-shirt under the coat, with the words 'Trust Me' written at the top. Below the words was a picture of Yoda, the green muppet character from the Star Wars films. There were words under the Yoda picture which read, ‘A Jedi I am’. I am not a big fan of Star Wars, but this was a very odd shirt, and at that moment, an image came to me. I had seen it before.
Wait, I saw you, at the train station, in the crowd. You were wearing that shirt, and unlike everyone else, you weren't panicking, you were just standing there.
Yes, that's right. You did see me, and I saw you. Frankly, I was a bit surprised you didn't recognize me when I met you downstairs. Perhaps your mind was on something else.
Yes, it was on gathering my juice. I only caught a glimpse of you. I guess it didn't register immediately because you were wearing the jacket now. But why were you just standing there instead of running? Where you not scared of the earthquake?
Why should I be scared, I knew there was no danger. And at any rate it was not an earthquake.
How do you know?
Because I caused it, and it was nothing really, a minor mishap. Don't worry, I took care of the situation and it won't happen again, we are quite safe.
--My guest's delusions of grandeur did not bother me as much as the realization that being in my apartment was all part of his plan.
So you followed me here?
Not exactly, I followed the juice.
What do you mean?
I needed your cherry juice. And though I would have brought you another case tomorrow, I thought you might think it rude if I just grabbed it from you while you were walking down the street.
Why would you want cherry juice?
While cherry juice is somewhat helpful to humans, it is even more helpful to me, as you can see. Plus it helps to hide me from their scanners.
--My thought then was that he was certainly insane and possibly schizophrenic. I felt somewhat sorry for him and tried to reason with him.
You do realize that while there are plant pigments in the juice, it doesn't actually make you look like a plant.
Of course. But notice that I am already hiding in your apartment, thus I have taken care of any exterior visual identification protocols. However, there are other ways of scanning. But don't worry, as I said I have everything un
der control. Let's continue with the story shall we?
--I was going to ask him who “they” were, but I really didn't want him to get into it. I wanted him to tell me what he wanted to tell me, and leave. He took a sip of juice and continued as if nothing happened.
I know of a creature that lives on a stormy desert planet similar in size to your earth. Unlike the earth however, this planet is tidally linked to its sun, hence the sun only shines on one side of the planet and the other side is cold and dark. On this planet, a female of the species lays her eggs many miles apart on the dark side of the planet, away from her children's many predators. Once her children hatch, their subconscious internal directional system sends them on a long journey through the cold and stormy desert. If they survive, the hatchlings will at some point reach the lit side of the planet, where the weather will be warm, and they will meet others of their species and spawn. These creatures initially are blind, since they are born on the dark side of the planet and do not receive much information in the form of light. Yet they are actually born with organs you might call eyes. However, these eyes are dormant, they are not engaged until later in life, when they get closer to the illuminated side of the planet. These young creatures, though highly intelligent, often do not meet any other sentient beings for quite a while as they blindly travel the vast and desolate desert surface of their planet.
Sounds like a difficult life.
Yes, now imagine looking at the world through the eyes of these solitary creatures, walking through the desert. Initially they do not see, so what they know about the world is defined by their sense of touch. As they walk, they touch things; rocks, strange insects, various cactus like life forms. They bump into things, and then they keep moving. They perceive the world in a very different way than you do. An object, say a rock comes into existence for them only when they touch it, since they can't see it coming, and when they no longer touch the rock, it disappears.
Well the rock isn't gone, it’s just behind them.