....It's about Time,
what's up with that? Bill Cosby once had a thought about "Why is there air?" Well there's air to fill up basket balls, there's air to ...
PreambleThere are several theories about time and it's origin. Since everything must have an origin and I trust a conclusion, we can see by example time has an origin but when it concludes, this would be shall I say a bummer. The end of time is the present school of thought not possible. But going (travelling perhaps) to a particular point of reference in time or to the reference of time at that point, we could actually view that reference in time.
Horse feathers you say! Just a minute how do we know, remember Al's theory about Energy = Mass times Velocity squared? This applied to the red shift observation of items travelling at a rate greater than ordinarily observed. You do the math thinking where this would take us with the recent "faster than light" discovery. The mind boggles.
High school physics tells us traveling faster than light is not possible. Forget that. It has been done, rather I should say that a particle has left a vessel before it entered, as the speed of light was used as a reference. We should also explore the fact that laws of time may also be "observed from other points of reference". Observe the night sky and tell me with absolute conviction that the light of the stars all got here at the same speed. For a second also consider the measure of time, is it per second? In reference to what second, and how do we check and ensure that "the second" was the same as the one in a few seconds from now, or then? At a different reference to the flow of time, is time measured in seconds different? This may sound like mumbo but can time be measured with complete accuracy? Bounce this around, can we say that time as we know it is constant? If our atomic clocks are subject to the laws around us, what then if the constant's that maintain these laws are not solid.
Try this, we have a gram of stuff and we know it is so because we measured it, what if we take it to the moon. Is it still a gram of stuff? Of course not. It now is under the moon's laws of measure. If we measured a second of time and take it to the far orbit of earth from where we are now, is it still a second. In reference to what?
Is time measured or is it assumed to be the measuring stick? From what I have read of late it could be a "unit" that has properties of light in that it is a particle or wave. It could then be created (light bulb / Time bulb) or bent (lens, as in light / black holes, curved space) or switched on and off.
There are also sound physical reasons to doubt the flow of time. The trouble started with Al's theory of relativity, the idea that time is not universal with a common present moment for everybody. Al showed that two spatially separated events judged to occur simultaneously by one observer can occur at different moments for another.
Imagine, I was reading
I was reading about an explanation about the second law of thermodynamics as it would be applied to time asymmetry that doesn't depend on time flowing. Explained in an example was a bottle of perfume that contains an ordered state of molecules in liquid form. Removing the cap and we have a disordered state of molecules as they escape and mix with the air. Given time I'm sure we can find the source of the perfume and determine the direction of flow.
Mystery sets in, however, when you try to trace the source of this directionality. The molecular agitation that jumbles up the perfume and air molecules involves lots of intermolecular collisions. But the collision of two molecules is a reversible process: run the movie backwards and the molecules retrace their trajectories. This reflects the symmetry in time of the laws governing molecular behaviour. Indeed, almost all the laws of physics are time-reversible. The puzzle is how temporally lopsided processes can emerge from time-symmetric laws.
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So, while the second law of thermodynamics requires that the arrow of time point from order to chaos, from disequilibrium to equilibrium, it seems that the early Universe started at equilibrium and is now far from equilibrium-all of which seems to point the arrow in the wrong direction. How can this be?
This is where gravity comes in
There is a caveat in the second law: it applies only to isolated systems. In the Universe, matter and heat radiation are not isolated, because they are free to engage in large-scale motion. This activity is subject to gravitational forces, and so we must include the gravitational field as part of the total system.
Gravity is an attractive force that tries to pull matter into clumps, ultimately this material falls together completely to form a black hole. Applying thermodynamics to gravity, the black hole can be seen as the equilibrium end state.
Attempting to find the equations that link gravity with thermodynamics is taxing the best brains in physics. But for a clue to how these two processes might be related from the standpoint of the arrow of time, it helps to think of order and disorder not in terms of clumpiness and smoothness, but in terms of information. A totally disordered state needs only a few bits of information to describe it. For example, the macroscopic state of a flask of gas in thermodynamic equilibrium can be completely described simply by giving its temperature and volume. But a gas with lots of hot spots and swirling eddies would take a lot more information to describe. As a system approaches equilibrium, it loses information irreversibly.
When a body collapses into a black hole, it loses information. The escalating gravitational field of the body traps light, and because information cannot travel faster than light, it is trapped too. Ultimately, an event horizon forms around the body, preventing any information from getting out. To an external observer, the information content of the collapsing body disappears irreversibly down the hole. Not surprisingly, therefore, black holes obey a set of laws identical to the normal laws of thermodynamics.
The second law of thermodynamics can be thought of as nature's way of driving systems towards equilibrium. If this law is taken to embrace gravitating systems, it describes a trend from smooth to clumpy.
If I can read into this and form an opinion, what is explained by the origin of time near the moment after the big bang and the demise of it near the black hole. Is time a non-renewable resource. Or as it was explained in one article that events on Mars are happening just as events on Earth are happening. Could they be at the same time? If so what of light (using this as a speed point of measure) reaching at different times to each body or at the same time differently? Is it time we are measuring or space, if it is space we are measuring is it not time as well? Is time and space the same the thing or is it the reference to one another?
Just as the laws of physics do not
favour a direction of time, neither do they favour a direction of space. Nevertheless, many physical systems have a definite orientation in space. For example, the Milky Way galaxy has a rotation axis that points to a particular part of the Universe. However, the rotation axes of other galaxies point in different directions, and overall there is no preferred alignment. So laws can have symmetries that are broken by actual physical systems. If our Universe didn't break the time symmetry of the laws and so produce an arrow of time, we wouldn't be here to notice.
