It seems almost everyone agrees that time goes by faster as we get older, I think the first time I noticed this, I was about 8 years old and remembering that when I was 4 the summers and winters lasted forever. Furthermore, I was not excited with the notion that I would be in school until I was 18 years of age. However, when I became 18 it seemed hardly any time had passed.
It is my belief that we judge increments of time in relation to how long we have existed. This means that a forty year old person experiences twenty years the same as a twenty year old person experiences ten years or yet, a ten year old experiences five years - all of them reflecting on half of their life. In another words one year to a sixty year old is one sixtieth of his/her life whereas one year to a 10 year old is one tenth of his/her life - And one tenth of your life is a much bigger piece of time than one sixtieth of your life. While I was excited to have this idea strike my mind in 1983, I am not surprised that it was first introduced in 1877 by Paul Janet. However, what Janet could not realize about this phenomenon (since Einstein's concepts were not yet introduced) is that we can metaphorically map the relationship of this perceptual time shift onto the concept of "time dilation" as it is used in Einstein's Special theory of relativity. I do want to mention that there are other psychological factors that affect the plasticity of time but I believe the one presented here has the greatest interest.
I would like to focus your attention to the concept of "Time Dilation". If you have studied a little bit of Einstein's Special Theory of Relativity then you may remember that the speed of light is constant in any frame of reference. This epiphanic concept serves as the inspiration for Einstein's special theory of relativity. To illustrate time dilation in the context of the special theory of relativity, imagine that a space ship capable of traveling close to the speed of light is given instructions to send a radio signal (which travels at the speed of light) to earth every second in its voyage. When the ship is on its launch pad the signals are received every second as expected. Yet, as the ship accelerates toward the speed of light the radio signals become further apart. In other words they are received, 2 seconds apart then 3 seconds apart 4, 5, - 10 seconds apart - 15, 45... in other words the closer the ship gets to the speed of light the longer the duration between the signals. In fact, when the ship is traveling extremely close to the speed of light, the signals could be received as far apart as one year or even longer. Let me reiterate the fact that the people on the ship have been watching their clock and sending their radio signal every second. The effect that is experienced by people back on earth is that they view time slowing down on the space ship. This phenomenon, in Einstein's theory, is called "time dilation".
Now the interesting thing to me, is that this is the same feeling that I experience when looking back at time in my life. The past seems to have slowed down almost as if I have been traveling in a space ship which is accelerating through some sort of "psychological space" where I am experiencing a "psychological time dilation".
"Physical time" can be viewed as an analog of psychological duration in our mind. For we use the harmonic motion of objects traveling in physical space as our standard for "physical time". The International System of Units (SI) defines one second as the time it takes a Cesium-133 atom at the ground state to oscillate exactly 9,192,631,770 times. Physical time changes little to none but psychological time changes incessantly.
Using this idea of increments of time based on our past experience I have written this computer program to map our "psychological time dilation" onto Einstein's equation for his special theory. This computer poem expresses a metaphor that raises questions to the nature of time.
The next page of this expression will ask you to input the names and birthdates of two people that you wish to experience this phenomenon with. I suggest, in this comparison, that you first try using the name and birthdate of one of your parents or your child and then use yourself for the second person in this comparison. The further apart the ages of these two people, the more drastic (and interesting) the results.
There will be three results in three separate windows:
The first window will show the calculation comparing the two people by using today's date as the point of reference. This comparison gives you a feeling for how fast one would have to be traveling, in an ultra-fast space ship, to experience this time dilation.
The second window is an interesting comparison due to the measurements being taken from a point in the past; specifically 1 day after the younger person was born. There is a surprising realization when we look at the comparison of relative velocity between the two people. We see that the spaceship is traveling almost the velocity of light. (approximately 99.9999999% the speed of light) Yet, the really fascination part of this comparison is when we imagine the instant the younger person is born. They break through the light barrier!
The Third window takes us into the far future showing a calculation that occurs over a quarter of a million years from now. When we analyze the experiential trend that occurs by moving our comparison dates into the far future, we see that there is very little difference between the two people’s experience of time. That concept is reinforced by noticing that the spaceship’s velocity has slowed down to a relative crawl. The most thought provoking aspect, for me, in this comparison is that we can see by extrapolating this data out further to the point of eternity - there is no difference it our temporal frame of reference and all humanity is one.
In the box below, please type the name of the first person that you would like to make this comparison with.
In the box below, please type the birth date for this person.
In the box below, please type the name of the second person that you would like to make this comparison with.
In the box below, please type the birth date for the second person.