Hi Aurino,
I will try to make my position clear on the issue you bring up; however, I don't really expect clear comprehension.
***** Aurino:
I have no complaints about your definition of time, except with the fact that it can't be measured.
*****
First, you must comprehend that, by my definition, time is nothing except a construct of the human mind introduced to make sense of what it knows. Continuity between events is a complete mental fabrication and not real at all: i.e., an illusion. From that perspective, the fact that it cannot be measured should not be surprising at all.
***** Aurino:
But there's a subtle problem here which I'm sure you understand: even though clocks can't measure time, it's quite likely that our subjective experience of time is controlled by a clock.
*****
No, from my proposed perspective, time is a completely subjective illusion. The fact that the illusion brings many phenomena into what seems to be an orderly progression is the central power of the effect and its reason for existing. Certain very orderly phenomena (in this illusion) are used to define what we call a clock. To think that our subjective experience of time is controlled by a clock is to get the whole thing backwards. Unless, what you mean by "is controlled by a clock" is that the continuity of the image so achieved is the driving force behind the illusion; in which case, I would agree with you.
***** Aurino:
And the problem here becomes one of finding a definition of time which is consistent with our knowledge of physics as well as our subjective experiences.
*****
Now, you see I am of the opinion that my definition of time is consistent with both!
***** Aurino:
I have raised a similar issue before, regarding the "water goes downhill" thing. While you're right that downhill is the direction water runs by definition,
*****
Be careful! What I said was that "If one defines downhill with a carpenters level ..."! Certainly there exist alternate definitions of downhill which do not make water run downhill by definition (the direction of my front walk to the driveway for example).
***** Aurino:
it's a known fact that there are places where people's subjective sense of their position in space conflicts with the direction water runs. Since our vestibular system is based on fluids in the brain, we can say for sure that the discrepancy is due to an optical illusion (we can also say for sure that it's not a vestibular illusion). For time, however, we don't have such a simple explanation, not as far as I know anyway.
*****
As you well know, I hold that most of what we know lacks any good explanation. So I just go with the flow. As you have commented earlier, you don't discuss religion. I am of the opinion that most of what we think we know is religion!
***** Aurino:
(PS: since you're back, can you reply to my technical question to Richard above?)
*****
The question you refer to appears to be this one.
***** Aurino:
Richard,
Since you are the only physicist around here, can I ask you a technical question? If "space" is just a set of coordinates, how do you express the concept of space expansion in mathematics? I mean, what do you use as a coordinate system?
I understand there's an answer, I just never found it anywhere. Too technical for laypeople, perhaps?
*****
I suspect we would both agree that his answer did not even begin to approach your question which, by the way, is a very intelligent question!
I will start by commenting that Einstein's Theory of General Relativity gives reality to "space". It is an entity with structure and properties sort of analogous to "aether" though it is sacrilege to say such a thing. Aether is a very hard concept to free the mind of. If you read about General Relativity, you will find the literature full of things like "wormholes" in space or space being "frothy" at the quantum level. All these ideas give "aetherisk" properties to "space".
Thus it is that, in their minds, space is not just a coordinate system in which to display data, it is something which can be probed and examined. Of issue is whether or not it is geometrically closed (like the surface of a sphere) or open (like a saddle). To them it is conceptually a "real" thing, not just a geometry embedded in a higher dimensionality.
In particular, it can be measured. Now the unit of measure used in cosmology is related to the speed of light (be it parsec, light-year or whatever). This converts time (which is defined by counting oscillations of a particular energy level in an atom or a nucleus - they keep refining this) into distance. Since the basic unit of measure is determined by definition from local measurements, one can reasonably say that the size of the Universe changes with time (the expansion). The average distance between galaxies increases with time. (If we could be confident that the measured distances are correct.) Now to me that is a pretty big if subject to many questions, but to the academy there is practically no "if" there at all. It is all very well understood if you don't believe me, just ask them.
With regard to Yanniru's answer, I think we are discussing "religion" (it's a religion called "science" but it is a religion none the less) and he is quoting catechism. I think you should take a close look at
http://www.electric-cosmos.org/
I have read the whole thing and, though there is a lot of snake oil there (snake oil is always attracted to new ideas as they depend on confusion for their existence), there is also a lot of good information which makes the current picture of the Universe very questionable. I think the possibilities are far beyond the rather short sighted concepts of the current authorities.
I hope I have not confused you!
Have fun -- Dick |