Tal, a conversation with an alien Read Online Free Page B

first you must understand what a dimension is. One definition of a dimension is that a dimension will give you a specific location in the universe. Generally, you think of a location in the universe as purely a spatial one, but it is more than that. We can do a little thought experiment of our own to make this clear. Let's imagine I write you a note that I am to meet you for lunch at a well-known location in the universe, let's say the Empire State Building in New York City. Do you know where that is?
    Yes, I have visited it before , it is at the corner of 34th Street and 5th Avenue.  
    You begin to read my note and it tells you to meet me in the Empire State Building at 34th and 5th. When you arrive, you do not see me. How could that be?
    Y ou have told me the avenue and cross street only. You could be in the lobby, or the 5th floor or the 105th floor. If you told me what floor, I could find you.
    Correct. You need to know the third dimension of space we are meeting at. You read the note further and see that is says: 34th street, 5th Ave, 50th floor. You take the elevator up to the 50th floor, but I am not there. Why?
    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, b ut 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