'Time' is defined and measured as a sequence of superordinate events, separated by well defined durations of other subordinate events. For example, one hour is separated from a successive hour (superordinate events) by subordinate minutes, the duration between the hours in minutes being 60. The same relation holds for successive minutes separated by durations of 60 seconds. Some scientists and philosophers hold that time is continuous, meaning that there is always subordinate events of some duration between any two superordinate events. I believe this to be wrong. I believe that time MUST be discreet (i.e. quantized). Why?
A 'now' can be considered an event (an event with a duration of zero as a limit). If time is continuous, any event (or 'now') can/must be understood as being comprised of subordinate 'nows,' with their accompanying durations. This can be understood in like manner as points on a line (continuous), where between any two there is always at least one more. Here is where we run into an example of Zeno's paradox, but instead of distance we are looking at time (i.e. durations). Therefore, for any now to exist there must be an ultimate duration where anything 'smaller' cannot be considered meaningful or even to exist. What I am talking about is the quantization of the time dimension. If time is continuous, any given 'now' must be made up of other candidates for a 'now' of smaller duration and those subordinate nows made up of sub-subordinate nows. Take this relationship out to its ultimate, infinite, extent and we can see that there can be no unique, individual now. There must exist a time quanta that when reached a true 'now' can be said to have manifested. That time-quanta may well be the Plank Time (10 to the -43 seconds), the time required for light to travel, in a vacuum, a distance of 1 Planck length, but that has not been unequivocally, experimentally determined. At this point, this ultimate 'now,' the universe must 'jump,' or bounce to the next now in much the same way as an electron suddenly jumps to a different orbital (or energy level), instantaneously, with nothing 'in between.'
Einstein's General Relativity (GR) predicts that time durations will slow down in the presence of intense gravitational fields or when moving at large speeds (approaching the speed of light). If a dimension like time did not exist, this 'dilation of duration' should not be observed. But in fact it is observed, experimentally, and this observation has been witnessed several times (no pun intended). The real question is “Does time exist as a separate entity, unchanging, an independent stage in which all events take place but is not affected by them, as Newton hypothesized?” Einstein's answer is no. Time is intimately engaged with space to form what is called the 'spacetime continuum (STC).' Both space and time experience a warping and bending in the presence of large gravitational fields. Because durations do exist (and can be altered by gravity and high velocities) a dimension of time in the spacetime continuum must be understood to exist. As John Archibald Wheeler once quipped "Time is how the universe keeps everything from happening at once."
Some theoretical physicists (e.g. Brian Greene) believe that spacetime, at any given point in the spacetime continuum, always exists - once it has manifested. For example, King Leonidas and the Spartan army is still holding off the Persians at that particular point in the STC. The light of the 'now,' like that of a film projector illuminating each frame, has not been extinguished; particular nows which occurred in what we understand to be the past always will exist at that point in the continuum. In the same way, what you did on January 10, 2005, that 'now,' still exists within the STC.
Time appears to have what is considered an 'arrow,' a particular direction of moving from what we experience as the past into what we consider the future. This arrow carries with it an increase of entropy, of the universe moving from a given level of disorder to a level of greater disorder. Most, if not all physicists understand and accept this notion. But like time itself, the 'amount' of entropy is also then quantized, and not continuous for the same reason that time is not continuous. For all of the reasons pointed out in this short essay, I believe it is erroneous to consider time as a chimera, as nothing but mere human imagination.
A 'now' can be considered an event (an event with a duration of zero as a limit). If time is continuous, any event (or 'now') can/must be understood as being comprised of subordinate 'nows,' with their accompanying durations. This can be understood in like manner as points on a line (continuous), where between any two there is always at least one more. Here is where we run into an example of Zeno's paradox, but instead of distance we are looking at time (i.e. durations). Therefore, for any now to exist there must be an ultimate duration where anything 'smaller' cannot be considered meaningful or even to exist. What I am talking about is the quantization of the time dimension. If time is continuous, any given 'now' must be made up of other candidates for a 'now' of smaller duration and those subordinate nows made up of sub-subordinate nows. Take this relationship out to its ultimate, infinite, extent and we can see that there can be no unique, individual now. There must exist a time quanta that when reached a true 'now' can be said to have manifested. That time-quanta may well be the Plank Time (10 to the -43 seconds), the time required for light to travel, in a vacuum, a distance of 1 Planck length, but that has not been unequivocally, experimentally determined. At this point, this ultimate 'now,' the universe must 'jump,' or bounce to the next now in much the same way as an electron suddenly jumps to a different orbital (or energy level), instantaneously, with nothing 'in between.'
Einstein's General Relativity (GR) predicts that time durations will slow down in the presence of intense gravitational fields or when moving at large speeds (approaching the speed of light). If a dimension like time did not exist, this 'dilation of duration' should not be observed. But in fact it is observed, experimentally, and this observation has been witnessed several times (no pun intended). The real question is “Does time exist as a separate entity, unchanging, an independent stage in which all events take place but is not affected by them, as Newton hypothesized?” Einstein's answer is no. Time is intimately engaged with space to form what is called the 'spacetime continuum (STC).' Both space and time experience a warping and bending in the presence of large gravitational fields. Because durations do exist (and can be altered by gravity and high velocities) a dimension of time in the spacetime continuum must be understood to exist. As John Archibald Wheeler once quipped "Time is how the universe keeps everything from happening at once."
Some theoretical physicists (e.g. Brian Greene) believe that spacetime, at any given point in the spacetime continuum, always exists - once it has manifested. For example, King Leonidas and the Spartan army is still holding off the Persians at that particular point in the STC. The light of the 'now,' like that of a film projector illuminating each frame, has not been extinguished; particular nows which occurred in what we understand to be the past always will exist at that point in the continuum. In the same way, what you did on January 10, 2005, that 'now,' still exists within the STC.
Time appears to have what is considered an 'arrow,' a particular direction of moving from what we experience as the past into what we consider the future. This arrow carries with it an increase of entropy, of the universe moving from a given level of disorder to a level of greater disorder. Most, if not all physicists understand and accept this notion. But like time itself, the 'amount' of entropy is also then quantized, and not continuous for the same reason that time is not continuous. For all of the reasons pointed out in this short essay, I believe it is erroneous to consider time as a chimera, as nothing but mere human imagination.
via International Skeptics Forum http://ift.tt/1TEnHMl
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