There is a limit/measure. The speed of light.
We say that 'the universe exists' to the extent that we have observed it.
Anything you say about the universe beyond that is speculative. Including claims of infinity.
There is a limit/measure. The speed of light.
Calculus would be fine with potential infinity only; it does not need actual infinity. No-one has any use for actual infinity apart from generating paradoxes.
The "arbitrary" mean time is not arbitrary. It is set by the time function. All relative times relate to the underlying time which is not arbitrary.Belinda wrote: ↑Tue May 28, 2019 11:02 pm JayJacobus wrote:
No . Timing depends upon an arbitrary mean time. There is no absolute time. The timing of any event is related to the timing of other events.If relative times are independent of each other, then they would not be calculable. They are calculable because they are all dependent on one absolute time.
https://www.theguardian.com/uk/2008/oct ... seyisland1
Relative to past and future times. The current time is t(curr). That relates to all t(previous) and all t(future). Each t is a state (not a dimension). t is repetitive. If t doesn't come from a function, it would be stationary and there wouldn't be any time at all.
jayjacobus wrote: ↑Thu May 30, 2019 6:50 pmRelative to past and future times. The current time is t(curr). That relates to all t(previous) and all t(future). Each t is a state (not a dimension). t is repetitive. If t doesn't come from a function, it would be stationary and there wouldn't be any time at all.
Clocks are synchronized by the mechanism and the mechanisms produce the same time because time is the same function for all clocks in relative time. The clock mechanism is not connected to any other clock thus something (time) must be keeping the clocks working in sync.Speakpigeon wrote: ↑Wed May 29, 2019 8:47 pmI didn't ask why clocks are synchronised. I asked why they stay broadly synchronised.So, what's the criterion?
Say we have two clocks. We synchronise them and we watch them. What's the criterion for deciding that the clocks stay synchronised?
Issac Newton, somewhat. The whole universe is at the same underlying time. When it's 12 o'clock on Earth, the whole universe is in the same state regardless of the individual times. So t(current) is the same t(current) across the universe. If this were not true we couldn't see stars that were in a different state.
It's much easier if you have three. http://citeseerx.ist.psu.edu/viewdoc/do ... 1&type=pdf
It's true that measurement is arbitrary and frames of reference are abstract but they refer to space and time which are natural and not arbitrary. Just because the measuring unit is arbitrary, doesn't mean that the natural phenomenon is.RCSaunders wrote: ↑Wed May 29, 2019 1:56 amTime is the relationship between the motion of entities. Just as length or distance and direction are the static relationship between entities, time is the relationship between entities when either their distance or direction from other entities changes (moves). Time, like length and direction, does not have any independent existense except as the relationship between entities that move.
Just as length and direction require some arbitrary unit which can be used to measure them, time requires some arbitrary unit of measure. Common ones are seconds, minutes, and hours. Just as there are no actual inches or feet, there are no actual seconds, minutes, and hours. All units of measure are human inventions.
Rulers and compasses are used to measure distance and direction, clocks are used to measure time. Rulers use a fixed length units and compasses used a fixed direction units. Since that which is being measured is change (in distance or direction) the device for that measurement (clock) has a fixed rate of change.
Time is not a substance or entity, it is a relationship. The relationships time is used to measure are real and exist, but only as relationships between physical entities. There is no time independent of those relationships.
But space is relationship between things. Space does not exist apart from how entities relate to each other. Time does not exist apart from how entities relate to one another.It's true that measurement is arbitrary and frames of reference are abstract but they refer to space and time which are natural and not arbitrary. Just because the measuring unit is arbitrary, doesn't mean that the natural phenomenon is.
Lot's of things have limits. What I said is that the universe (all physical esistence) has no measurable limit.
I don't know anyone who says that except you and whoever the "we" is you include yourself in. There is no reason to conclude what is not directly observed does not exist. If that were the case we'd have to consider the sub-atomic particles, "speculative."
Just out of curiosity, is it important to you (or to anything) that I and others do not accept a finite universe? Even if we are wrong, what harm does it do?
Yeah... that's an oxymoron. If you can measure something it has a limit.
Not in the least. You can SAY that you "don't accept a finite universe" as much as you want, but any thing you call "understanding" (as in epistemology) of the universe is in finite form.
I have more sympathy for your view than you might think. It is easy to think of space as a thing because we think of it as where every thing is. In one sense that is true. The mistake in thinking that makes space some kind of metaphysical existent, a thing, or a substance existing with its own attributes like any other existent. But space has no attributes and we do not measure it. What we measure is the relationships between existents, their distance from each other and their direction from each other. The very same is true of time. What we measure is the relationship between the motions of physical existents which relationships actually have two measurements, velocity and time. While no one is clamoring to prove the existence of velocity as thing even though everything has a velocity relative to everything else, that is the very claim that is made about time, which is no more a thing than velocity is.
This orderedness that you call "well behaved" has been invented by men (but not discovered as an everlasting fact ) about the Universe.I understand what you are saying but I must point out that space is well behaved. To get from one space to another you need to travel through many spaces. And the shortest distance is a straight line. Space connects and separates. So even if space cannot not be discerned, how it works is obvious. It doesn't have to be the way it is. Space could be disjointed so that you can't travel from point n to point z or that location d does not separate but contains many objects. But space is well behaved and so even though you can't analyze a particular space, in total it has characteristics.
The same can be said about time. Time proceeds in a consistent way. To get to January 1, 2020 you have to go through every time in between. Each time has the same length as every other time. All operations in the universe are a function of time. You can't analyze any particular time but in total time has characteristics.