[yor_on]

Uniform motion is not locally measurable. You need to introduce frames of reference to define different speeds, which doesn't mean that any of those frames by themselves suddenly found it changing locally. Two different things actually, and when you measure 'c' in a two mirror experiment you always do it locally.
=

you can by using frames of reference define it 'globally' but it becomes questionable, the same way an ' eye of a God ' (a 'outside') is questionable. That's not the way we define it geometrically, we do it from the inside.

[yor_on]

You need to check up on 'two mirror experiments' Halc. They are so defined :)
You can pick any sun you like in front of you, I could also have written that one could put a scale under ones feet to check if one accelerated, I didn't, should I?. And yes, it's SR, I stated that in my first reply to those wondering what I meant by 'c' being both a local constant at the same time I discussed it as 'observer dependent'. The first is 'locally defined', the second is 'globally defined'.

How hard can it be to get it?

"  Central Postulates of Relativity: (SR)
    The laws of physics are the same for all uniformly moving observers.
    The speed of light is the same for all observers.

Yes, but I'm not stating that 'c' won't be 'c' locally measured. I'm stating that there is no golden standard for a uniform motion, from that follows that 'c' is a relation to your acceleration, not a relation to a 'relative motion'. I'm also stating that although relative motion can't be defined locally measured, we can still prove different 'speeds'.
=

Think of it in 'black box scenarios' to see how I mean.  "


another angle on the problem.

Assume yourself to be infinitely close to the speed of light in a vacuum (uniform motion).
Setup a two way mirror experiment inside and at rest with your ship

What will it measure?

Or as I think Einstein once wondered, what happens to light if I look into a mirror at 'c', Will I still see myself.

[guest4091]

I'm wondering Chiral. This is collected thoughts on 'c' as a variable. http://www.ldolphin.org/cdkconseq.html

with a time dilation you could argue that 'c' changes too, from the 'eyes of a God' so to speak. See if you can find something interesting

from the paper:
"The permeability of space was apparently related in some way to the stretching out of free space at the time of creation (Genesis 1:6-8, Psalm 104:2)".
Genesis is not about creation of the universe, but the preparation of earth for life forms.
Psalm 104:2: isn't about the earth, but 104:7 is.
This is interpretation to suit their agenda.

[yor_on]

Halck and Phyti, this is just redirecting the thread into something that could be discussed somewhere else. When I gave that link it wasn't because of whether the guy writing it had opinions of his own. It was because I found some value in the questions and answers. And when it comes to my thoughts I shouldn't have discussed them here.

Let's get back to Chiral's Idea instead.

[chiralSPO (OP)]

Thanks for bringing it back (I'm not opposed to having some tangents along the way, but the closer we can stick to the main question, the more likely it is that I will learn the answer) 

[jeffreyH]

I think at this point it is worth waiting to see what a cosmologist thinks.

[guest4091]

chiraSPO;
e naturTime is simultaneously (sorry) a simple concept and a difficult one to grasp. Clearly, our perception (as human beings) of time is not entirely quantitative. There are many different biological and psychological aspects of our perception that I do not want to delve into. Rather, I would like to discuss purely physical and mathematical interpretations of time.
I have had many questions about time swirling in my head for a while now, and I think I can distill them into two primary questions:

(1) Is time the most fundamental "temporal" dimension, or is it a function of an unrecognized dimension?
This question comes about when trying to conceive of an absolute time scale. Every equation I have come across in my education in the physical sciences deals with dt or Δt, and so is really just dealing with relative time (t = 0 is arbitrary or internally defined, and any indefinite ∫f(t)dt will have that pesky "+ c" term).

Many people point to the Big Bang as thal t = 0, but this raises at least as many problems as it addresses.

[Time is not a dimension in the same sense as spatial extent. It's a measurement of activity. The method of measurement can be any periodic process and is typically a  device (clock) which produces periodic clock events, with the period defined to suit an area of human activity. Eg. the hour and minute for common daily human activity, seasons for agriculture activity, or the nanosecond for scientific research. The clock period is equivalent to the uniformly spaced marks of a ruler used to measure spatial intervals. The comparison is even more obvious when measuring distance using light. This is an operational definition of time and is consistent with a history of using the motion of astronomical objects to measure time.

Applied time is a correspondence convention, assigning a clock event to an event of interest. It is a personal diary, or any historical records, in a variety of mediums.
Mathematical expressions use time as a correspondence and as a variable. 'As a function of time' is just a convenient figure of speech. Time (clock events) are assigned after the event of interest, so how can it be a causal factor?
The theory of Special Relativity demonstrates there is no absolute time or simultaneity, but subjective time, which is affected by motion in space, which results from the independent speed of light. Einstein did not explicitly refer to SR or GR as a theory of perception, but with the observer as the primary component, it definitely is such. Just as in quantum theory, the observer is part of the measurement process.
If timekeeping only has meaning to humans, then time before their appearance has no meaning. Anything prior is pure speculation.]

[yor_on]

I don't know Chiral, we need a experiment that might work?
I think that's the thing you need for the proposal

The 'energy' at a Big Bang should be limitless right?
Somewhat alike a time dependency maybe ?

[yor_on]

Sounds simple, doesn't it?
But what frame of reference will you use?

Now?

[Bill S]

Phyti, in general, I have no problem with the content of your post, but would like clarity on a couple of points.

The clock period is equivalent to the uniformly spaced marks of a ruler used to measure spatial intervals.

Agreed; but space “exists” independently of any marks on a ruler, are you proposing that the “existence” of time is dependent on measuring instruments?

…. Time (clock events) are assigned after the event of interest, so how can it be a causal factor?

Would it not be right to say that it is the measurement/recognition of the time interval in which the event occurred, that is assigned after the event? 

I agree that assigning a time to an event does not establish any sort of causality, but isn’t time necessary (whether it is measured, or not) to enable change can happen?

[guest4091]

Bill;

Phyti, in general, I have no problem with the content of your post, but would like clarity on a couple of points.

Phyti;
The clock period is equivalent to the uniformly spaced marks of a ruler used to measure spatial intervals.
Bill;

Agreed; but space “exists” independently of any marks on a ruler, are you proposing that the “existence” of time is dependent on measuring instruments?

[response]
['Space' exists, but if it has no known structure, i.e. no elements to serve as references, then we are limited to measuring the differences in location of objects in space aka distance. We use a defined standard of distance, a ruler or a specified number of wavelengths of light of a given frequency (equal to a unit of 'time').
The clock supplies a standard interval between 'ticks' that provides a perspective of the rate of activities. A race car completes a mile course in 30 sec, moving fast at 120 mph. A store clerk notices an hour go by with no customers, business is slow.
An hour glass, water clock, sun dial, a burning candle, earth rotation...all examples of physical processes used as clocks, practical devices for scheduling human activity.
'Time' as applied by human convention requires measurement. Eg, a worker wants to be compensated for his hours of labor. Time can be classified as record keeping/accounting for human activities. A process, not a physical thing.]

Phyti;
…. Time (clock events) are assigned after the event of interest, so how can it be a causal factor?
Bill;

Would it not be right to say that it is the measurement/recognition of the time interval in which the event occurred, that is assigned after the event? 
I agree that assigning a time to an event does not establish any sort of causality, but isn’t time necessary (whether it is measured, or not) to enable change can happen?

[Only if you see 'time' as an activating agent or force.]
–------------------------------------------------------------------------------------------------------------------------------
Points to ponder:
Consider two identical atomic clocks, one on floor 1 and one on  floor 2. If there is a universal time agent, why don't they both run at the same rate?
Why do they vary when moved, in any direction?
Radioactive particles decay at random. How would 'time' do that?

We don't need 'time' to explain these. We have gravity and independent light speed, and quantum behavior.
a=g
v=gt
x=gt2/2
math definition (abstract figure of speech): "v and x are functions of t".
observational truth: "an object falls to the ground via the gravitational field".
'time' played no part in the process of falling, but is convenient for measuring.
Eg:
A small mass is released from a height, and recorded by a video device which time stamps each frame.
A graph plots the height on a horizontal axis and the corresponding ‘time’ on a vertical  axis , both with a uniformly spaced scale.  The graph will show a curved trajectory, indicating acceleration of the mass.

homework:
Imagine being isolated in a cave, with the essential stuff to survive, but not receiving any cues from outside. You have to write an account of your experiences until someone signals via a communication system on the surface. How do you record the time of events in the account?.
--------------------------------
OTEOMB, A. Einstein,1905, par 1:
"Now we must bear carefully in mind that a mathematical description of this kind has no physical meaning unless we are quite clear as to what we understand by ``time.'' We have to take into account that all our judgments in which time plays a part are always judgments of “simultaneous events"

In SR, the time of an event is the awareness (perception) of the event according to a local clock.  The awarenesss of an event can only be after its occurrence. Additional distance info is required to assign a time to the occurrence event.

If none of this informs, you might check ‘Father Time’ on Wiki.
He should know!

[Bill S]

If none of this informs…….

Thanks, it is interesting and informative.  There’s just one question it doesn’t answer.

Radioactive particles decay at random. How would 'time' do that?

I certainly don’t see time as an activating agent or force. My answer to this question would be: It doesn’t.

A small mass is released from a height, and recorded by a video device which time stamps each frame.

If time exists only as a measure of events that have already happened; how can the events happen?  How can your “small mass” change its position in a timeless environment?

[guest4091]

Bill;

Water is lifted from oceans, lakes, etc. via sunlight, carried via winds to different locations.
At higher elevations the vapor cools, condenses on dust, falls to ground via gravity, seeks lowest suface and returns to those reservoirs of water.
It's a sequence of events enabled by physical processes already in place. One of many natural cycles. Where would we be without natural recycling!

[Bill S]

Phyti, I have no problem with any of that.  What I don't see is how these cycles could operate in a timeless environment.

Cycles involve change.  How can there be change if there is no time in which it can happen?

[Bill S]

Having looked, briefly, at this thread, thoughts about the "madness" of repeating the same thing, and expecting a different result come to mind. 

[yor_on]

You know Chiral, that isn't that far away from how I think of 'c' myself. What differs us is that you use what I would call a 'global approach' to it whereas I start to think of it in local terms. Maybe you could think of it in terms of frequencies? What would happen to them if 'time' runs slower at a 'origin' than 'now'? Everything should blue shift to us measuring at this time, right? And the closer we get from the 'early light' to 'now' the less blue shifted the light should be.. If I now got it right :)

[yor_on]

I am not discussing a Black Hole, and light reflected or released Halc. I'm thinking of it in terms of a 'slower' 'time', as observed 'now'. Even if 'c' still stay 'c at all 'times'' the view point from 'now' should resolve in a apparent blue shift for us, as it seems to me
=

yes, I see how you thought there. The way I think of it here is one from where you roll a movie faster. Everything speeds up relative the observer.
==

Or maybe it would be less blue shifted, although if you count in a inflation it seems to me that this should compress, no, I'm not sure how to think about that one. But thinking of it in those terms should get you to a blue shift anyway. Thinking of it in terms of a 'infinite point singularity' aka a 'white hole' you get a red shift, but that one does not include Chiral's scenario, the way I look at it now.

http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/universe.html

[yor_on]

Actually Chiral. You could go out from a accepted model of the cosmological redshift, as defined by a "static 'c' " in main stream physics. then back track 'now' to the Big Bang, and see if there is something that would turn out differently if 'time' indeed has 'speed up'. What makes it tricky is this balance you would need relative all other constants, keeping them the same except 'time' then. With a 'slower speed' of time comes a (apparently) faster 'c' presuming it to be a natural constant, unrelated to 'time'. If you connect it to 'time' though it will keep its balance invariant as a 'clock'. But that doesn't stop us watching the 'cosmological movie' from finding 'things' being 'speed up', as it seems to me?
=

I'm discussing it in terms of a apparent blue shift here, as that is the analogy to a higher 'speed' for light. But? I'm not sure that would work If you could zoom in on something happening 'then'. Everything should be 'speed up' to us, shouldn't it?

Actually, thinking of finding it this way, using main stream physics for defining it, might be considered as 'constants' having changed.

[Bill S]

Oops! I left the link out of #121.

https://www.thenakedscientists.com/forum/index.php?topic=53002.msg445400#msg445400

[guest4091]

Phyti, I have no problem with any of that.  What I don't see is how these cycles could operate in a timeless environment.

Cycles involve change.  How can there be change if there is no time in which it can happen?

You are in that group that interprets 'time' as a causal entity. It's like trying to separate Linus from his security blanket.
We can add seeds, programs that produce plants, another cyclic process, DNA for animal and human reproduction.  Animal behavior, more programs, also cyclical. Do you see a trend here, processes in place that 'make things happen'.You get more variety when human thought intervenes.
Eg., man does not want to ride a horse, invents carriage.