[MikeS (OP)]

E=mc²

Mass and energy are conserved.
The more energy you have the less mass you have.  The more mass you have the less energy you have.

The speed of light c has two components DISTANCE which is the SPACE dimension of space-time and TIME the TIME dimension of space-time.  The faster you travel in space the less you travel in time.  The faster you travel in time the less you travel in space.

That appears to me to be a conservation law but with time itself being conserved.  Space and time are conserved quantities but are interchangeable.  This is the same as mass in the form of matter and energy being conserved but interchangeable.

This leads to two questions.

1)   Is space-time conserved?

2)   If space-time is conserved how can space expand without time contracting?

[imatfaal]

Mike stop posting your ideas in the main forum

[Ęthelwulf]

E=mc²

Mass and energy are conserved.
The more energy you have the less mass you have.  The more mass you have the less energy you have.

The speed of light c has two components DISTANCE which is the SPACE dimension of space-time and TIME the TIME dimension of space-time.  The faster you travel in space the less you travel in time.  The faster you travel in time the less you travel in space.

That appears to me to be a conservation law but with time itself being conserved.  Space and time are conserved quantities but are interchangeable.  This is the same as mass in the form of matter and energy being conserved but interchangeable.

This leads to two questions.

1)   Is space-time conserved?

2)   If space-time is conserved how can space expand without time contracting?

We often say something is conserved over time, not that time itself is conserved. That would not be enlightening since time is a universal invariant. It's always there anyway, unchanging.

[MikeS (OP)]

E=mc²

Mass and energy are conserved.
The more energy you have the less mass you have.  The more mass you have the less energy you have.

The speed of light c has two components DISTANCE which is the SPACE dimension of space-time and TIME the TIME dimension of space-time.  The faster you travel in space the less you travel in time.  The faster you travel in time the less you travel in space.

That appears to me to be a conservation law but with time itself being conserved.  Space and time are conserved quantities but are interchangeable.  This is the same as mass in the form of matter and energy being conserved but interchangeable.

This leads to two questions.

1)   Is space-time conserved?

2)   If space-time is conserved how can space expand without time contracting?

We often say something is conserved over time, not that time itself is conserved. That would not be enlightening since time is a universal invariant. It's always there anyway, unchanging.

That's why I said "with time itself being conserved."
Time is not a universal invariant.  It is only invariant in any local frame.  Different non local frames are not invariant.  From our reference frame on Earth, the atomic clocks of global positioning satellites have to be corrected for time dilation effects.

I agree considering space-time to be conserved is not a normal concept as conservation laws normally operate over time.  However, we accept, well  most people accept, that the length of a second varies with gravitational potential but it's not at all intuitive.

[Ęthelwulf]

Yes, it is invariant locally. But then time is local.

The absence of finding a global time in GR however makes your question redundant, if you were meaning it in a global sense. You can't speak about a conservation if the object doesn't exist on a global case.

Recently I conjectured you can't speak about a conserved quantity of energy for the global case of a universe because there is a vanishing global time due to the WDW-equation. This arguement is different however because we do not argue that energy is absent. Only the necessary tools capable of describing such a symmetry in the theory.

[Ęthelwulf]

By the way mike, when I was banned you answered to a thread concerning the Suprachiasmatic Nucleus. I said it was the reason for our sense of time which you disgreed and said it only answered for circadian rythms. You where only partially right. I was more right in the sense that it does explain our short-range sense of time. There is a long-range sense as well, called the Ultradian is our sense of time-keeping in the long sense

http://en.wikipedia.org/wiki/Ultradian

and read this - it is mentioned here as well

http://en.wikipedia.org/wiki/Time_perception

If you can refresh my memory which thread it was in, I will answer you directly there as well.

[MikeS (OP)]

Yes, it is invariant locally. But then time is local.

The absence of finding a global time in GR however makes your question redundant, if you were meaning it in a global sense. You can't speak about a conservation if the object doesn't exist on a global case.

Recently I conjectured you can't speak about a conserved quantity of energy for the global case of a universe because there is a vanishing global time due to the WDW-equation. This arguement is different however because we do not argue that energy is absent. Only the necessary tools capable of describing such a symmetry in the theory.

We know time can be viewed both locally and from a distance.  When viewed from a distance time varies from locality to locality.  Everywhere in the universe has local time.  I really cannot see any reason why the time dilation factor can not be averaged (theoretically) universally.  It seems to me that time is a universal feature of the Universe, it just varies with locality and probably over cosmological time. 

Gravity dilates time.  If the universe is expanding then presumably gravity here on Earth is steadily becoming weaker.  If gravity is becoming weaker then over cosmological time, time on the Earth is contracting.  If it happens on the Earth then it happens throughout the Universe.  Time may be contracting.  Could it ever be proven?  I don't see how but neither can it be dis proven.  Is there any evidence that time may be contracting?  Yes the red-shift but that could also be evidence of expansion.

If you know of evidence why time has to be non global I would be interested to know.

Gravity exists throughout the Universe but varies from locality to locality.  Presumably it could be averaged theoretically.  Time arises (partly) as a result of gravity.  If gravity is universal and time is intimately related to gravity how can time not be universal.

[Ęthelwulf]

The Wheeler de-Witt equation is the quantized form of the EFE-equations. That the global time description vanishes is often taken to mean that a global time cannot be found. The absence of a global time however may imply a singularity of spacetime http://fqxi.org/data/essay-contest-files/Minguzzi_timecontest.pdf .  But essentially, the WDW-equations describes time for a universe, and if its time derivative vanishes like it does, we may imply that we live in a timesless universe - but I have explained this loads of times here.