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View Full Version : Realtivity of Units of Measurement & Expansion of the Co



heusdens
2003-May-18, 12:27 PM
General Relativity explains that - when measured in normal meausering units - that the universe is expanding. This conclusion is based on a choice of measuring units. However, one can designate an alternative set of measuring units, that explains that the universe is not expanding.
How? Well when we define the length unit to be that of a large distance in space, seperating distantiated galaxy clusters, and compensate for the relative motion relative to the CMBR, we could as well conclude that space is not expanding. This is a weird conclusion, but nevertheless an outcome of a new choice in measuring unit.

When compared to our normal lenght units, this new length unit seems to be expanding in the course of time. And not only the length unit behaves different in the new measuring system, but also time. If we state that the speed of light is not only constant in each intertial frame of reference, but also constant in disregard of this new measuring unit system, this explains that the new time unit, when measured in the normal time units, also increases in time. This then explains why light, that was emitted at a constant frequence billions of years ago, seems to have decreased it's frequency when arrived here.

Nice feature of this new system of measuring units is that when measured in these units, neither the universe expands, neither a begin of time is necessary.

russ_watters
2003-May-19, 02:54 AM
One necessary property of a unit of measurement is that it must be reasonably constant, otherwise its pretty much meaningless. So no, you can't make a unit of distance that is bigger for longer distances.

heusdens
2003-May-19, 11:20 AM
One necessary property of a unit of measurement is that it must be reasonably constant, otherwise its pretty much meaningless. So no, you can't make a unit of distance that is bigger for longer distances.

What I propose is that within nature we can in principle think of two systems of measuring units.
One that conforms to our standard that material forms (like atoms) are entities with some invariant properties. This is of course the most common perspective. Our unit of measurement denotes the size of an atom as a invariant quanity.
The other is to envision that long distance cosmological length scales and properties of space itself, are invariable.

Now which of those is to be hold absolute. They are mutualy variant. We have a strong preference for the firs measuring unit system, for mostly practical purposes.
But that in itself does not give rise to a fundamental argument against the alternative measuring unit system.

Unless of course, you can explain me what Nature has absolute measuring units for length, time, etc. Apart from the circular argument that these measuring units are invariant, how do you know they are?
You have to make a comparance with something else, to state that something is invariant, isn't it?

(One way of reasoning coud perhaps be that space is not a entity on itself, but a 'product' of matter, and therefore not to be considered the primary entity, so all measuring units should conform to absolute measuring units, based on material invariant properties within matter)