After watching Stephens King’s the Langoliers, it got me thinking about some of my own assumptions about the past. I have always assumed that the past continued to exist just as the present exists. But could it actually be that the present ceases to be or warps into something completely different once it becomes the past? Is there anyway to test this?
I’ve read on this board that the smallest divisible distance is the length of Planck’s constant. Is this only true for 3d distance or is it also true for time? In other words, does time progress at the rate of Planck’s constant?
One can think of a 3 dimentional object as a slice or cross section of a much greater 4D reality. The smallest slice is defined by the Planck Interval…approx. 10^-44 sec.
If we treat time as a physical dimension like length, than any stationary point on the 3D object is actually travelling along the 4D superobject at a velocity of c…we are all going at the speed of light, into the future.
Now wether or not we can test the physical existence of whether or not something in the future or past exists is meaningless: you cannot define a point in the future or past as an object in the present. You can measure a point in space against a timeline, but how do you define a point in time? You would need an independent timeline, and our universe has only one dimension of time.
First, ignore King as a source of information about science. One can’t really answer a question about “what the past is like now” without some very careful definitions of your terms (I don’t know of any meaningful way to do it, myself), but the version in The Langoliers obviously doesn’t make any sense. If the seats are “still” present in the past, then why aren’t the people sitting in them “still” there, as well? Or if one makes some silly distinction between living and nonliving matter, why not at least their clothes?
As for the Planck scale, there is some scale at which the laws of physics as we know them no longer apply. Nobody’s quite sure what this scale is, but the Planck scale is a reasonable enough guess. Note that this does not mean that the laws of physics themselves break down, only that our current understanding does, and there’s no reason to suppose that a time less than the Planck time can’t exist, only that we can’t currently describe it physically. It’s also important to note that what sort of limit the Planck scales are depends on how you’re looking at them. The Planck mass, for instance, can be considered to be an upper limit to the masses which can be described by our present quantum theories, or as a lower limit to those describable by our gravitational theories.
I have never heard space-time described quite this way before. It’s very useful. So is it because time is travelling at the velocity of c that the closer another object approaches c the slower time is perceived? Is also why it is said that if you go faster than light (if such a thing was possible), you would be traveling backwards in time?
The 4D object I describe is commonly known as a World Line.
Imagine your world line as a long wormlike object in 4D spacetime, beginning at your birth and ending at death.
An interesting thing about worldlines, spacetime and antimatter.
Richard Feynman discovered that a positron (anti-electron), plotted on a Feynman diagram (a particle path plotted on a diagram with space and time coordinates) moving foreward in time looks EXACTLY like a normal electron moving BACKWARD in time!