Chasing the black holes of the ocean

John Merryman

Tom,

I've certainly read the standard description many times. That does not explain the assumption of two standards for space;

Which is space? That which expands, or that which is measured by C?

Regards,

John M

John Merryman

Tom,

To try to save us both taking this debate around Robin Hood's barn for the nth time, let me try to clarify it as best as possible. Above you asked the following question;

" What measurable effect would one or the other -- vacuum or empty space -- produce, if they are not the same thing?"

Now I think they are the same thing. The problem is that current cosmology does distinguish between them. This model states space, the distance between points on the balloon, for instance, is expanding, yet we are able to measure the results of this expansion, because it will take light longer to traverse the distance. This means there are relatively stable units, lightyears, that we can use to measure the increase.

So since you have referred me back to this standard explanation, I have to note that it still does not explain how there can a stable speed of light in that vacuum which is distinctly different than the expanding space. Can you point out where this difference between the vacuum and space is covered?

Regards,

John M

Thomas Ray

John, I'm not sure what you think the debatable point is.

You seem to think that space is independent of time. Only spacetime is physically real, according to general relativity.

If you want to be a relativity denier, you'll have to debate with someone else.

Best,

Tom

John Merryman

Tom,

I'm not a relativity denier, nor am I a basic math denier, as this model is. The problem is that the space between two points is not three, or four, or five, or ten dimensions. It is one dimension. This theory argues it can expand, yet assume a constant against which this expansion can be judged, without appreciating the constant is the ruler. The constant is the denominator, so the variable is the numerator.

Regards,

John M

Thomas Ray

John,

I'm afraid that if this is what you think, you are indeed denying both the relativity and the math.

Best,

Tom

John Merryman

Tom,

How is it relativistic to have length extension, without a corresponding increase in the clock rate? That is no different than two people walking away from each other. If anything, this theory ignores relativity.

Regards,

John M

Thomas Ray

"How is it relativistic to have length extension, without a corresponding increase in the clock rate? That is no different than two people walking away from each other. If anything, this theory ignores relativity."

What theory are you talking about, John? Expanding spacetime is a solution to general relativity, and an observed phenomenon.

In any case, you are again asking the wrong questions. There *is* a corresponding increase in clock rate -- at *relativistic* distances and speeds. I have given up any hope of you looking at the mathematics which explains this, and will repeat once more that it is much easier to learn the math than to fumble in the dark.

Best,

Tom

John Merryman

Tom,

It is not expanding when you are explicitly using lightyears as the standard!!!!!

It is just an increasing number of such units.

Regards,

John M

Thomas Ray

John, a lightyear is a measure of time, as well as of space. Hence the term, "year," an interval of time.

Since you mentioned two people walking away from each other, let me try and explain it this way:

Suppose you and your friend propose to signal each other every ten paces. You start out hollering "hello," and following a number of iterations, you notice that the signal grows fainter and takes longer to reach you. When sound is no longer adequate to communicate, you use flashlights. Now you find that your friend's light beam takes the same amount of time to reach him, as his light takes to reach you.

You determine that you are x light-seconds apart. Space and time appear to be absolute, with a constant speed of light.

That will be good enough for all practical applications; even a relatively complicated task like landing a person on the moon needs no more signalling power than the absolute space and time of Newtonian mechanics. All the phenomena are what relativsts call "timelike separated," meaning that your ordinary intutition of how space and time are supposed to look is not offended.

When we calculate the relativistic effects of cosmic distances and/or velocities, we find that intervals of spacetime look very different to different observers. The "pop quiz" link is by Professor Andrew Duffy at Boston University.

Best,

Tom

pjackson

John,

Assumption of 'nothing' ends in paradox. Starting from a 'ground state' which acts as a valid datum has no theoretical problem. The problem imagined as an 'add on' to SR causing all the problems, is simply removed by letting these datums be spatially limited and move, which is exactly what we find in nature.

Something is in the 'absolute' vacuum, with known qualities, including the 2.7 degrees! Even current theory can't work without 'dark energy' and 'dark matter'. If you don't like those names think of another i.e. The 'condensate'. Assigning that a 'state of motion', which is what present doctrine won't do, is the only way to resolve all the theoretical issues faced.

A wave on the surface of the ocean is not all 'up', it's half up and half down. The ground state is 'flat', but it cannot be 'zero'! Why would you want it to be?

Peter

John Merryman

Tom,

Try as I might, I'm just not seeing how all this resolves the issue. If two galaxies are moving away from each other, such that it will take light longer to travel from one to the other in the future than it does now, how is this materially different than the two people walking away from each other, with flashlights?

The argument is that this is a four dimensional expansion that just can't be modeled in three dimensions, yet the space between any two points is still one dimension and that can be modeled very simply.

Regards,

John M

Thomas Ray

" ... If two galaxies are moving away from each other, such that it will take light longer to travel from one to the other in the future than it does now ..."

What future? Is your friend on the other end of a flashlight signalling you from the future?

Consider the light from a star far away that takes, say 100LY to reach your eyes. In your frame of reference, the light from that star originated long before you were born and spent 100 years of *your* time on its journey. You call that the past. From the reference frame of a hypothetical observer near the star, however, who receives light from our sun, *you* lie in *her* past.

Best,

Tom

John Merryman

Tom,

Remember the presumption is that eventually these other galaxies will no longer be visible, because they will have moved too far away. That is the future I'm referring to.

As I keep pointing out, mathematically, galaxies are not inert points of reference, but "space sinks," so that while the space between them can "mathematically" expand, it then falls into these wells at and equal rate and there is no overall expansion, thus resulting in the overall flat space that is observed.

Physically, it is that radiation expands and mass contracts, in a cosmic convection cycle.

Regards,

John M

John Merryman

Peter,

"Something is in the 'absolute' vacuum, with known qualities, including the 2.7 degrees!"

2.7k is still not absolute zero. We can't reach absolute zero, but does that have to mean space emerged from a point, 13.8 billion years ago? Why can't space just be space, even if it always has some level of energy?

Regards,

John M

Thomas Ray

" ... eventually these other galaxies will no longer be visible, because they will have moved too far away. That is the future I'm referring to."

Whose future?

"Physically, it is that radiation expands and mass contracts, in a cosmic convection cycle."

If you say so. How would you go about showing that, in a physical experiment?

Best,

Tom

pjackson

John,

Space IS 'space'. It's just not 'nothing'! You're only using an ingrained assumption that it is, which never has consistently corresponded with any evidence, even back to Pascal.

And it is of ultimate importance in allowing a logical universe that is is the 'something' we find. I ask again, why do you wish it to be nothing?

If you like we can have 'nothing' between the many universes. Does that help?

Peter

John Merryman

Tom,

Presumably the future of the universe, as galaxies move apart.

We see those distant stars, lightyears away and galaxies up to billions of lightyears away because they radiate light and other spectrums of energy, which is fueled by the mass falling into them. The only real question is how would the radiant energy cool and coalesce back into the most elemental forms of mass. M=e/c2

Given what the alternative has to explain, from what gave birth to the singularity, inflation, dark energy, etc, it seems a minor proposition to consider.

Regards,

John M

John Merryman

Peter,

As simple dimensionality, sans the physical matter and energy occupying it, it would lack any properties to bound or move. Which leaves it with the properties of infinite and absolute.

Regards,

John M

Thomas Ray

John, you were so close in asking the right questions. Now you've reverted back to a naive "stuff happens" view. E = mc^2 describes the rest state of matter/energy. Stuff doesn't happen.

Best,

Tom

Thomas Ray

"As simple dimensionality, sans the physical matter and energy occupying it, it would lack any properties to bound or move."

Wrong. Didn't I link this sometime previously? From David Weinberg at Ohio State.

Best,

Tom

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