What is "spacetime" really?

[Michael Mooney]

Backing up to unfinished business with you, Modest... (my replies in italics):

QUOTE=modest;257696]Notice your way of determining absolute distance involves the *measuring* of time,

 

I am not calling the *actual distance* between objects "absolute." Measure of light minutes (or years) is standard science for distance, like kilometers, miles or "AU." Distances vary for all the well known reasons, none of which is point of view/velocity of observer.

It is shown by general relativity and it has been experimentally verified that time moves faster at higher altitude and slower at lower altitude.

It is shown and verified that clocks tick faster at higher altitudes, etc. You continually assume that time is "something" besides the ticking of clocks... the ontology of which this thread challenges.

This is known as gravitational time dilation. While a ray of light moves from the earth to the sun a person located on the top of a mountain will experience more time than a person in a valley. They can both time how long the light takes to make the trip, but even if they use identical stopwatches, the two measures of duration will be different.

 

I am not now and have never argued for an absolute frame of reference for "time"... Rather I have always agreed that clocks keep time differently after being subjected to forces which change their inertia and give them different velocities... and higher altitude creates a different velocity for clocks relative to lower altitude clocks... as they have different velocities relative to say the center of earth.

 

So, any value you give for universal and absolute space and time is choosing one such reference frame over all the other valid reference frames.

As above... Not! But our standard measures of time are based on precise fractions of earth rotation as clocked in reference to a "fixed" or distant star... to define "one complete revolution." So one standardized earth-commensurate second is defined as the exact fraction of that revolution as measured (I presume) from sea level at at the equator. This will also address the remainder of the paragraph below.

 

It would force you to choose a spot on the mountain and say “that is where universal time can be measured—that is where time runs at the universal rate. A little further up the mountain and things experience more than the absolute and universal duration and a little bit lower on the mountain and things experience less than the absolute and universal duration." I can think of no way to choose such a frame.

 

It is nice, however, to see you say that measurements or observations of distance and time are different depending on velocity. I think this would make even more sense if you stopped thinking of space and time (or distance and duration—as you like to call them) as frame independent-quantities or as things that exists on their own in the universe. Space and time cannot exist in isolation.

 

Again, philosophically speaking, do you or do you not believe that cosmos exists objectively in and of itself independent of relative observational perspectives? Please answer, and the rest of the argument will automatically be resolved!

 

They (like velocity) are frame-dependent quantities that must be related to something or they loose their meaning. That is the essence of being *relative*. It is not human observation or human measurement that makes distance and duration relative. It is, rather, the fundamental nature of these things to exist only as a relationship to a frame of reference.

 

This argues that the reality of the cosmos absolutely depends on whatever local point of view... or "frame of reference. "Try for once "thinking outside the *frame*!" Can you imagine a cosmos as a whole as "seen" from transcendental perspective rather than from local frames of reference? It seems that you can not or will not, and therein lies the basis of this (now tedious for everyone, I'm sure) argument.

 

The quote below from Encyclopedia of Time also comments on this, but it is more directed at what you bring up about cosmic velocity from the big bang.

 

My cosmology is not here the subject. It is based on multiple bangs and crunches, perpetually cycling, as actual "stuff" expanding out into *empty space* until eventual gravitational reversal into the implosion half of the cycle resulting in the "crunch" and then the next Bang. Do not assume your favorite model to be the last word and established Truth, as many cosmological models are still active candidates, including "mine."

My context was to illustrate agreement with you that the "velocity of Mars" is not an absolute, but relative to what... as I clearly stated in reply to your challenge. We could also consider its velocity as part of our solar system relative to the center of the galaxy... etc. The point is that its orbital velocity and average distance from the sun are well known and published... and that doesn't change in every "frame of reference" scenario you come up with to illustrate relativity.

 

 

 

Right, Mars' velocity relative to the sun (or the sun's reference frame) is well-known. Just as well-known is the distance between the sun and the earth or the earth and mars as relative to the sun's reference frame. The point being: there is such an entity that these distances are relative to. Much like velocity, kinetic energy, electric current, or momentum, the concepts of distance and duration require a reference frame to be relative to in order to have meaning. It is for this reason that they are not absolute or universal. They depend on being compared to a velocity.

Again, no claim that they are absolute or universal... just objective and actual relative to each other... the bodies,,, not observational frame of reference.

 

 

 

This is a slight misunderstanding of big bang theory. There is no particular spot in our universe away from which everything is expanding;..

See above. The jury is still out. I say the cosmic ball of "all there is" keeps cycling through perpetual bangs and crunches. Glad to discus possible dynamics later. (Preview: Large scale supernova model with many crunches, not all matter at once, therefore scaled down to a scaled up supernova model...

 

nevertheless, what you're saying can be reworded in a way that is both consistent with standard cosmology and keeping with what you're saying.

No need to put words in my mouth. The model I have "seen" is very clear and I have written extensively about it in other forums. May go to the right forum section here for "Bang/Crunch" model variations.

Meanwhile, please consider the possibility that your position as moderator does not automatically confer infallibility. ;)

 

Michael

[Michael Mooney]

I'm not sure what you mean Pyro. Who was suggesting that the act of observation caused something, I mean, besides Michael? ...

~modest

Modest,

While awaiting your reply to my last post, I must clarify what I have been "suggesting" as exactly the opposite of what you attribute to me above. I have consistently maintained, at the very heart of my argument with you that "the act of observation" does not cause variation in actual distance between objects. You are the one who denies the actual, objective distance, sun to earth and to the other planets, giving examples (over and over) of how different observers at different velocities relative to each other and relative to observed objects come up with different distances based on differences in their perception, the latter differences of which are well established by relativity and allow for corrective calculations to establish the real, actual distances in all cases. (Whew!)

 

As for my last post, maybe we can resolve this more directly, if you will as I *pleaded yet again* just answer my question:

... do you or do you not believe that cosmos exists objectively in and of itself independent of relative observational perspectives?

Pretty please... with the topping of your choice! :)

 

Michael

[Michael Mooney]

Another loose end:

Erasmus:

You wrote:

It (math) implies physical things about the universe- the math of general coordinate invariance(subjective labels don't matter) implies that the universe is a curved, 4 dimensional manifold.

 

I responded without reference link:

..

See the essay earlier in this thread, link provided by Modest, on the ontology of non-Euclidean space, time and spacetime. (Wish I could search and link easily but am "challenged" in such things.) Pay special attention to the intrinsic vs extrinsic "curvature" paragraph.

(Will find it and share when I find time.)

Here is the link:

The Ontology and Cosmology of Non-Euclidean Geometry

 

.... and here is the quote:

In non-Euclidean geometry and its application by Einstein, the most important conceptual question is over the meaning of "curvature" and the ontological status of the dimensions of space, time, or whatever. The most important point is that the ontological status of the dimensions involved with the distinction between intrinsic and extrinsic curvature is a question entirely separate from the mathematics....

 

If you are interested in discussing the basic assumptions of non-Euclidean geometry, the basis of the model in which "the universe" is a four dimensional curved manifold, I am willing.

I could again lead off with the non-Euclidean departure from the Euclidean axiom... that the shortest distance between two points is a straight line... and ask if you "buy" this first departure, and if so... based on what information or trick of the mind.

Michael

[Michael Mooney]

Modest,

A brief review of discrepancies in what you have claimed about the "relative" vs the "actual" distance between objects... (My present comments in bold):

 

Originally Posted by Michael Mooney View Post

You misunderstand the basis of my objection to Modest's insistence that there is no such thing as actual, objective distance between objects...

Modest:

I have not said that there’s no such thing as *actual* or *objective* distance. I have objected to your description of *absolute* and *universal* distance and time. Absolute means no possibility of change and universal means applicable to all situations. The opposite of absolute and universal is “relative” which means subject to the comparison of something else.

 

"Absolute" or "transcendental perspective" as I use it in this context is identical with "actual" and "objective" as contrasted with the various relative measures of distance which require corrective math to determine "actual" distance.

 

Time, space, simultaneity, and mass are relative *not* absolute and universal.

 

As I've said dozens of times, time is not an actual entity but an artifact of "clocking" event duration... certainly not an "absolute." And space... (Yawn!) is emptiness, nothingness... not even malleable... certainly not absolute, though infinite as in "without end."

 

The distance between the earth and moon is actual and objective to both the person on earth and the astronaut, but it is not absolute and universal because the distance is different for the two of them. The distance as determined in earth’s reference frame is no more real than the rocket’s reference frame. They both describe how the physical world actually physically exists. It is *not* the case that there is one ‘real’ distance or duration and all these other reference frames are just observing things differently because of some effect of perception. It is not as you say here:

 

Originally Posted by Michael Mooney View Post

This distance, and the distances to the other planets does not change through some mysterious force of observation moving them closer or further apart. Because of the limits of lightspeed in conveying images, the distances may appear to change but they do not.

So how does this fit with your claim above : "I have not said that there’s no such thing as *actual* or *objective* distance.?

 

Finally, here is a review of our previous debate on the same subject. Your denial of "actual, objective distances" in favor of (paraphrased) 'all distances are relative to frame s of reference' is clear and undenieable.

 

(From) http://hypography.com/forums/philosophy-of-science/17037-what-is-spacetime-really-17.html

 

Originally Posted by Michael Mooney

The distance between two objects at any moment is objective in the sense that it does not depend on local perspective of observers 'seeing' the objects within the limitation of lightspeed as a conveyer of what is seen.

 

Modest:

 

Can a person determine this objective and transcendent distance?

 

You've explained that the transcendent distances between bodies in the solar system are well-known and have been measured scientifically. You then explain that transcendent distances do no depend on local measurements. These two lines of thought seem at odds which is why I've previously asked how exactly a person such as you or I is to determine the objective or transcendent distance.

 

MM

See post to arkain above. I believe that the measureents as given above (solar system distances and to alpha centauri) are objective as determined by our best scientific measurements today. (See philisopical context in my last post.)

 

Originally Posted by Michael Mooney

I have attempted to explain that, beyond local perspective, the proper viewpoint of relativity (in which "it is all relative) is a dimension of "absolute" reality. In this dimension, the average distance earth to sun is actually, objectively, independent of who sees what from where, about 93 million miles or 8 + light minutes.

 

Modest:

 

How did you determine this distance without measuring it? How does your cosmic perspective determine it? I need a reproducible method. I need you to describe in steps from start to finish how I can use your cosmic perspective to find that distance.

 

Originally Posted by Michael Mooney

I have challenged you to admit that all science websites will give such standardized and "objective" distances between "the usual objects of interest in the solar system and beyond.... which you continue to deny

 

Modest:

 

You're on a science site, Michael.

 

MM:

.....

I am absolutely amazed that I must quote to you the standard, well known precise measures of distance to familiar objects in our solar system.

 

Quoting:

"Windows to the universe":

.....

For example, Saturn's orbit around the Sun has an average radius of 9.5 AU, which means that Saturn is about ten times farther from the Sun than Earth is. The average distance from the Sun to distant Pluto is about 40 AU. Mercury, the planet closest to the Sun, orbits at an average distance of 0.39 AU.

 

AUs are generally used for measurements of distances within our Solar System. Distances to stars are much larger, and are expressed in terms of light years. One light year is equal to more than 63,000 AUs. The nearest star, Proxima Centauri, is just over 4 light years away.

 

Then quoting "WikiAanswers":

What is the distance of all planets from the sun?

" Mercury

Minimum Distance from Sun: 0.31 AU ( 46.00 million km or 28.58 million miles)

Maximum Distance from Sun: 0.47 AU ( 69.82 million km or 43.38 million miles)

 

Venus

Minimum Distance from Sun: 0.72 AU ( 107.48 million km or 66.78 million miles)

Maximum Distance from Sun: 0.73 AU ( 108.94 million km or 67.69 million miles)

 

Earth

Minimum Distance from Sun: 0.98 AU ( 147.10 million km or 91.40 million miles)

Maximum Distance from Sun: 1.02 AU ( 152.10 million km or 94.51 million miles)

 

Mars

Minimum Distance from Sun: 1.38 AU ( 206.67 million km or 128.42 million miles)

Maximum Distance from Sun: 1.38 AU ( 206.67 million km or 128.42 million miles)

 

Jupiter

Minimum Distance from Sun: 4.95 AU ( 740.57 million km or 460.17 million miles)

Maximum Distance from Sun: 5.46 AU ( 816.52 million km or 507.36 million miles)

 

Saturn

Minimum Distance from Sun: 9.05 AU ( 1353.57 million km or 841.07 million miles)

Maximum Distance from Sun: 10.12 AU ( 1513.33 million km or 940.34 million miles)

 

Uranus

Minimum Distance from Sun: 18.38 AU ( 2.75 billion km or 1.71 billion miles)

Maximum Distance from Sun: 20.08 AU ( 3.00 billion km or 1.87 billion miles)

 

Neptune

Minimum Distance from Sun: 29.77 AU ( 4.45 billion km or 2.77 billion miles)

Maximum Distance from Sun: 30.44 AU ( 4.55 billion km or 2.83 billion miles)

 

I think this puts the argument in perspective. And it "aint" about me claiming a special privileged viewpoint. In this context "objective" simply means "as it is" as distinct from "as it is perceived relativistically." "Absolute" is only used in the context of transcending relative perspective, as all the above measures of distance do.

Michael

Michael

[watcher]

hi MM.

 

As I've said dozens of times, time is not an actual entity but an artifact of "clocking" event duration...certainly not an "absolute."

 

iow, something is flowing and time is what we use to measure that flow?

i understand already that space is empty and euclidean to you. so it simply an inert background of material activities, and i supposed that matter is what flows right?

 

so what is mass? and if you think time is an artifact,

please try to define mass without referring to time. after all by common sense something as real as mass can't interact with an unreal time isn't it?

how would you explain gravity if you reject GR explanation to it?

i suppose in your model, lightspeed adds up and can be subtracted with other velocities too?

 

And space... (Yawn!) is emptiness, nothingness... not even malleable... certainly not absolute, though infinite as in "without end."

 

so why does the density of forces varies not only with mass but also with distance if space is a not a thing, inert and non-interactive ? i mean should it be that if gravity is purely based on mass... the gravitational force between object will not vary? iow, objects should not accelerate towards one another but pulled in constant velocity. so why do the force increases as they go nearer? it sounds like a stupid question but it demonstrate that space is not a simple background of everything but participates in its dynamics.

 

so to say that space is a no thing is just an unnecessary postulate and means nothing.

what is a thing anyway (ontologically)?

 

ps. btw, can you solve zeno's paradox of motion if space is background nothing? if that is so, nothing will move in the universe. imo

[Erasmus00]

Michael, I'm familiar with the article, but I point out that whether or not the curvature has an extrinsic component, it always has an intrinsic property. i.e. gravity cannot be described by a 3-d space or 4-d Euclidean space. This is enough to rule out your ontology of time and space.

 

Whether or not the 4-d space is embedded in a higher 5-d space (ortho-curvature) or not (hetero-curvature) is largely irrelevant to your ontology.

[modest]

Ok Michael. Let's see where we stand. A clock can/can't reach the sun in less than a minute? A clock can go from the earth to the sun advancing less than a minute? Yes/no?

 

That question, which has occupied so much of our time, is a question separate from the ontology of what the clock measures. If you are satisfied that the above answer is yes (it does happen as special relativity claims it does) then I will be satisfied that we are past that misunderstanding.

 

~modest

[Michael Mooney]

Ok Michael. Let's see where we stand. A clock can/can't reach the sun in less than a minute? A clock can go from the earth to the sun advancing less than a minute? Yes/no?

 

That question, which has occupied so much of our time, is a question separate from the ontology of what the clock measures. If you are satisfied that the above answer is yes (it does happen as special relativity claims it does) then I will be satisfied that we are past that misunderstanding.

 

~modest

So it's back to the same ol' samole' and you are not going to address any of the many points I've made in the above few posts to you... even the most basic question having the ability to resolve the argument... (yet again, all facetious "pleading" aside):

".. Do you or do you not believe that cosmos exists objectively in and of itself independent of relative observational perspectives?

 

Anyway, I will answer your questions (tho it seems only fair that you answer mine as well.)

 

" A clock can/can't reach the sun in less than a minute?"

 

Can't. No way. Nothing travels faster than light, which takes over 8 minutes to travel the distance. (I've said this more than a dozen times before!... but still you ask!)

 

" A clock can go from the earth to the sun advancing less than a minute? Yes/no? "

 

Given that clocks slow down when accelerated to high speed (and stay slowed down at new velocity relative to a control "stationary" clock)...

 

Other than the fact that it would burn up approaching the actual sun...

though I personally don't know the upper limit of speed a clock can be made to reach given the math of its increase in inertial resistance (equivalent to increase in mass, I believe?)... or whether somewhere near lightspeed would slow it down that much....

With all the above reservations... theoretically, yes.

 

Your turn.

Michael

[Michael Mooney]

Michael, I'm familiar with the article, but I point out that whether or not the curvature has an extrinsic component, it always has an intrinsic property. i.e. gravity cannot be described by a 3-d space or 4-d Euclidean space. This is enough to rule out your ontology of time and space.

 

Whether or not the 4-d space is embedded in a higher 5-d space (ortho-curvature) or not (hetero-curvature) is largely irrelevant to your ontology.

 

Gravity can be described as masses mutually attracting each without a "curved medium," space being "something" rather than "nothing" between them. Gravity can be described by its effect on other bodies and their trajectories *through empty space* without positing "space curvature." Which leaves my ontology of time and space intact. How the force of gravity traverses space is still an open question.

 

I was hoping to start from ground zero with you, prior to the assumption that Non-Euclidean curved space is "real" (more than a metaphore) and that Euclidean space is debunked beyond all question.

 

So the "ground zero" question in this context is, again: "Do you believe that the shortest distance between two points is a straight line? If not, explain how not in terms that are ontologically real... i.e., not "virtual", pretend, as- computer-modeled, etc.

 

Thanks.

Michael

[Pyrotex]

...I must clarify what I have been "suggesting" as exactly the opposite of what you attribute to me above. I have consistently maintained, at the very heart of my argument with you that "the act of observation" does not cause variation in actual distance between objects. ...

Hi, Mooney.

I did not phrase my response correctly to your original post.

You indeed said that "the act of observation does not cause variation in the actual distance between objects."

I was trying to say that Relativity does not claim that the act of observation...etc.

I was trying to say that you were arguing against a "strawman" interpretation.

If you were trying to say that Relativity DOES make that claim, I was trying to clear that up -- because Relativity does NOT make that claim.

 

I hope that helps.

 

Now, as to your use of the phrase "actual distance between objects".

Relativity (or Einstein) says that there is only "one" distance between two objects -- and that is the distance you "observe".

In other words, it is meaningless to speak of an "actual distance" if you cannot observe it.

We can speculate and assume and what all, but we cannot claim that there must be a "Distance" (with a capital D, to indicate that this is the Absolute Distance) which we cannot observe or never have observed.

 

Now, two different observers may, indeed, observe Different distances between the two objects. :hihi: We can "argue" that one observation is "senior" to the other because:

the observation was made from a convenient Frame of Reference (FOR); or

the observation was made from the Earth's FOR; or

the observation was made from the Sun's FOR; or

the observation was made from the FOR of one of those two objects; or etc, etc.

 

And this is all perfectly valid. It's generally what we do. The Earth-Sun distance we "observe" is made from the Earth's FOR and we (arbitrarily) choose that as the "official" distance. And it becomes "well-known" and "standard" as you have said. Nothing wrong with any of that.

 

But there is no ONE, uniquely correct, absolutely correct distance.

 

All distances must be observed.

All distances must be measured.

All measurements must be made from some FOR -- one or another.

And NO frame of reference is "privileged" over the others, in the sense that it enables observations that are more correct than observations made from other FORs.

 

This leads to the conclusion that there is no "actual distance" in the sense that it is the one and only

uniquely correct, absolutely correct distance.

[watcher]

hi michael,

 

".. Do you or do you not believe that cosmos exists objectively in and of itself independent of relative observational perspectives?

 

yes. there is a cosmos exists objectively.

but also yes that all perspective is relative.

 

imagine a cylindrical rod is observed by A and B. A's pov is along the length of the rod. so it is seeing a circle. B is perpendicular to the length of the rod, so it sees a rectangle.

 

theoretically every point in 3d space are all possible perspective.

is there an ontological cylindrical rod that exists? YEs

is there an infinite possible perspective exists? yes

is there an absolute perspective? NONE.

 

the nearest idea to an absolute perspective you can have is the superposition of all possible points of view. similar to the the shroedinger wavefunction superposition of all possible states.

 

but you cannot have a comprehensible pov in a superposition state, at least not in science.. so for every measurement to be possible, you must first fixed your gauge so to speak.

in Qm, you have to determine first the total energy of the system and assume it is conserved before attempting to measure anything.

 

in relativity, fixing the gauge is to get the the relative speeds of objects to be measured relative to c (s-t interval). objects in motion has specific energy to them. energy determines the wavelength and frequency. high moving objects have hi frequency and short wavelength. low moving objects have low frequency and longer wave length.

 

we measure distances by the wavelengths and we measure time by frequency. thus hi moving objects measures their surrounding shorter distances and duration compare to slow moving objects.

 

is there an absolute cosmos. yes. is there an absolute perspective, none.

is there an absolute distances between objects? none because you have to fix your gauge. objects in varying speeds are located in varying spacetime realms layered much the same way as spectra of waves. that is why objects at varying speeds don't "see eye to eye". two objects must have the same energy or velocity before their respective measurements of distances and time agree. iow, the higher the energy in the system, the smaller the cosmos is, relatively speaking.

 

Do you believe that the shortest distance between two points is a straight line?

 

it depends on the velocity or the energy contents of these points. if the velocity of two points are equal, the shortest distance is a straight line. if there is a large difference of velocity/energy bet the points, the nearest distance is a curve. iow, the only way to "connect" them or reach one another is thru a curve.

 

given that, the ontology of cosmos encompasses and transcends several spacetime dimensions. and you may be talking a different "no thing" space and not the physical aspect of spacetime. and this ontological cosmos makes itself known by being quantifiable and measurable. but there is no absolute measurement. this cosmos therefore has given up its absolute nature to exists and be observable in an infinitely possible way. cool eh?

[Michael Mooney]

Pyrotex,

Thanks for the clarification. Very helpful.

 

Specifically:

You indeed said that "the act of observation does not cause variation in the actual distance between objects."

I was trying to say that Relativity does not claim that the act of observation...etc.

I was trying to say that you were arguing against a "strawman" interpretation.

If you were trying to say that Relativity DOES make that claim, I was trying to clear that up -- because Relativity does NOT make that claim.

 

And you later wrote:

Relativity (or Einstein) says that there is only "one" distance between two objects -- and that is the distance you "observe".

In other words, it is meaningless to speak of an "actual distance" if you cannot observe it.

 

So... This is the "Philosophy of Science" section. This allows respectful discussion of the ontology of space, time, distance (the linear component of space applicable to the question "How far is it between A and B.") ("How long does it take whatever to travel from A to B at whatever speed?" brings in the time component of course but is a different question.)

 

At this point, my history as a mystic with visions is causing an undue prejudice against me here. I am not in fact claiming a privileged, absolute perspective as part of my argument, as it is not "science" in its present materialistic, relativistic form. (I do not and will not deny the clarity of my visions or the belief that they are true visions of "what is." But my info source is admittedly not "scientific" as it is understood from the prevailing worldview of scientific materialism.)

 

So, again I beg the indulgence of all scientists here to engage in a *thought experiment* in which there *is* a transcendental, cosmic perspective independent of all local frames of reference. In this experiment, cosmos exists *as it is* regardless of local observations of it. (The latter *is* the realm of relativity, with which I am not arguing... not have I ever.)

 

Then... all of the "standard measures of distance", as in my list for this solar system above, are actual, objective distances. Regardless of point of view (from earth, sun or other planets.) The "measuring rod" of lightspeed as applied to all above distances (say, by a virtual, transcendental, cosmic observer) will remain exactly as listed above. To clarify... I am not speaking relativistically of the "measuring rod of lightspeed" as objects are observed from various local perspectives.... (Please indulge the experiment)... but the *actual* distance light travels in a given precise time interval between each of the bodies in the list above... independent of who sees what from where and when relative to each observer.

 

You said, and I agree that there is an actual, objective cosmos "out there." I was encouraged by your common sense in contrast to the philosophy of subjective idealism, which is patently absurd, as it *does claim* that observation and subjective interpretation creates reality. You claim that we can not know the nature of the True cosmos because of the local limitations we have beaten to death in this discussion. Yet how is it that you deny the objective distances above. I do grant that relativity is an excellent corrective tool for the effects of relativity on observation. I am not arguing against a strawman in this regard.

 

Put philosophically, the question remains... and no one will answer me directly:

Do you or do you not believe that cosmos exists objectively in and of itself independent of relative observational perspectives?

 

If "yes" then distances between objects are actual and objective regardless of viewpoint of measurement. If "no" you are indeed back to "relativity" making all distances vary with perspective of measurement, and there is no "actual cosmos out there...as is.. independent of observation."

 

Then there remains the whole question of "the ontology and cosmology of non-Euclidean geometry" (and curved, expanding, etc "spacetime.")

 

The starting point for this discussion is prior to the assumption that Euclidean geometry, space, cosmology has been debunked and that non-Euclidean space is, if not "proven" at least holds the best "hand" of evidence.

 

So my question in this regard, also totally avoided by all moderators remains:

""Do you believe that the shortest distance between two points is a straight line?"

 

Please address these points, as Modest refuses to do so.

 

Michael

[Michael Mooney]

Watcher,

I think my reply to Pyrotex, just posted will also address much of your last post.

I admit that much of what you write seems to ignore answers I have already given in depth, and I don't want to keep repeating myself.That said, a few replies (in italics.)

 

W: "yes. there is a cosmos exists objectively.

but also yes that all perspective is relative."

 

Can you imagine a cosmos with no intelligent life forms "observing?" Does the distance between objects then disappear sans "observation?" Ans: No.

 

imagine a cylindrical rod is observed by A and B. A's pov is along the length of the rod. so it is seeing a circle. B is perpendicular to the length of the rod, so it sees a rectangle.

 

I am really tired of the rod and clock arguments which illustrate relativity quite well. So... skipping down...

 

theoretically every point in 3d space are all possible perspective.

is there an ontological cylindrical rod that exists? YEs

is there an infinite possible perspective exists? yes

is there an absolute perspective? NONE.

 

Yet again, what is exists independently of local perspectives and observer error... which the tools of relativity correct quite well. Do you get my point... at last?

 

the nearest idea to an absolute perspective you can have is the superposition of all possible points of view. similar to the the shroedinger wavefunction superposition of all possible states.

 

As I suggested to Modest... can you "think outside the frame" of local reference, even for a philoshical moment? "All there is" is the cosmos/universe as it is. There is no need for " the superposition of all possible points of view."

 

"given that, the ontology of cosmos encompasses and transcends several spacetime dimensions....

This is *not* a "given." Space is emptiness. Cosmos is the stuff that exists in space. Space is 3-D and "time" is what "elapses" as the dynamic cosmos moves... whether the partws are being "clocked" or not. I grant four "dimensions" if time is to be called a dimension without reification... slowing/speeding as if it were an event itself.

 

and you may be talking a different "no thing" space and not the physical aspect of spacetime.

You constantly use "spacetime" as if we had agreed that it is ontologically "real" as if you were totally new to this thread. It makes me impatient with you. Space has no "physical aspect", nor does time.

 

and this ontological cosmos makes itself known by being quantifiable and measurable. but there is no absolute measurement. this cosmos therefore has given up its absolute nature to exists and be observable in an infinitely possible way. cool eh? [/i]

 

Cosmos "gives up" nothing in the absence of measurement, by any life-form anywhere.

 

but you cannot have a comprehensible pov in a superposition state, at least not in science.. so for every measurement to be possible, you must first fixed your gauge so to speak.

in Qm, you have to determine first the total energy of the system and assume it is conserved before attempting to measure anything.

 

I am not arguing against the usefulness of measuring devises not the mathmatical tools which interpret the measurements for more accuracy in the relativistic paradigm. Please understand this before you reply again! This will apply to the rest of your post.

 

is there an absolute cosmos. yes. is there an absolute perspective, none.

 

Maybe its about the phrase "absolute perspective" which smacks of religious belief... of which I have none. How about distinguishing between what is and the limits of relative points of view, locally.

 

is there an absolute distances between objects? none because you have to fix your gauge.

 

With no humans and no "gauges", the distance between objects remains "as is" changing only as objects move around relative to each other.

 

(MM: "Do you believe that the shortest distance between two points is a straight line?")

 

it depends on the velocity or the energy contents of these points. if the velocity of two points are equal, the shortest distance is a straight line. if there is a large difference of velocity/energy bet the points, the nearest distance is a curve. iow, the only way to "connect" them or reach one another is thru a curve.

 

I am speaking of the first axiom of Euclidean geometry here. If the two points are moving away from each other, obviously the distances between them increases. Under no circumstance does the shortest distance between them at any given moment become other than a straight line. A curved line between two points will always be longer than the straight line, regardless of what non-Euclidean "mind trick" you would like to apply.

 

Michael

[Erasmus00]

So the "ground zero" question in this context is, again: "Do you believe that the shortest distance between two points is a straight line? If not, explain how not in terms that are ontologically real... i.e., not "virtual", pretend, as- computer-modeled, etc.

 

Define straight line? The shortest distance between two cities on Earth (or two points on a globe) is NOT a straight line but a great circle.

 

Also, you shouldn't confuse things you can visualize with things that exist. I cannot visualize a hyperbolic geometry, but there is no physical principle that prevents them from existing.

[Michael Mooney]

Define straight line? The shortest distance between two cities on Earth (or two points on a globe) is NOT a straight line but a great circle.

 

Also, you shouldn't confuse things you can visualize with things that exist. I cannot visualize a hyperbolic geometry, but there is no physical principle that prevents them from existing.

"Straight line": Not bent or curved, or crooked. I mean "straight" in the only true sense of the word (for a line!) There may be synonyms, but they elude me at the moment.

"The shortest distance between two cities on Earth (or two points on a globe)"... is a straight line through the earth or a rod poked through the globe from one city to the other. Please respond and show how the surface length (on earth or globe) is shorter than the straight line through earth/globe.

You should not confuse things that I can see (I did not say "visualize"... your word), that do actually exist... with thinbgs that you can only visualize. Do not project your "physical senses only" paradigm on me. There is actual "seeing" beyond the physical senses, tho I do not expect you, obviously a rocket scientist with a strictly materialistic worldview, to accept my vision as "seeing what is." I merely expect you to respect the possibility and abandon your claim that the physical senses (and their scientific, high tech extensions) are the only way we can (now or ever) "see."

 

But the latter difference is a big can of worms. I would very much appreciate it if you would at least respond to the "shortest line" Euclidean argument above and tell me how a curved surface is the shortest line between two points on earth or a globe. Think "straight through." The curvature does not define the reality of "the shortest distance."

 

Michael

[modest]

Do you or do you not believe that cosmos exists objectively in and of itself independent of relative observational perspectives?

If nothing in the universe existed relative to anything else then the cosmos would cease to exist in any meaningful way. Beyond that, your use of the word objective continues to confuse me.

 

A clock can/can't reach the sun in less than a minute?"

Can't. No way. Nothing travels faster than light, which takes over 8 minutes to travel the distance. (I've said this more than a dozen times before!... but still you ask!)

 

A clock can go from the earth to the sun advancing less than a minute? Yes/no?

...With all the above reservations... theoretically, yes.

Do you see what you did? You've chosen clocks on earth (and rulers on earth) to describe you cosmic reference frame. You've given priority to our human perspective here on earth.

 

All clocks and rulers are created equally. You've gotta get past the idea that the ones on earth are somehow special. Once you recognize that clocks and rulers moving different velocities from your own will measure different durations and distances from your own then it's a straightforward step to recognize that there's nothing special about our measures of distance and time—it is just the way space and time exist relative to our velocity—which is not special or privileged.

 

Hi, Mooney.

I did not phrase my response correctly to your original post.

You indeed said that "the act of observation does not cause variation in the actual distance between objects."

I was trying to say that Relativity does not claim that the act of observation...etc.

I was trying to say that you were arguing against a "strawman" interpretation.

:) Yes, precisely that.

If you were trying to say that Relativity DOES make that claim, I was trying to clear that up -- because Relativity does NOT make that claim.

 

I hope that helps.

 

Now, as to your use of the phrase "actual distance between objects".

Relativity (or Einstein) says that there is only "one" distance between two objects -- and that is the distance you "observe".

In other words, it is meaningless to speak of an "actual distance" if you cannot observe it.

We can speculate and assume and what all, but we cannot claim that there must be a "Distance" (with a capital D, to indicate that this is the Absolute Distance) which we cannot observe or never have observed.

 

Now, two different observers may, indeed, observe Different distances between the two objects. :shrug: We can "argue" that one observation is "senior" to the other because:

the observation was made from a convenient Frame of Reference (FOR); or

the observation was made from the Earth's FOR; or

the observation was made from the Sun's FOR; or

the observation was made from the FOR of one of those two objects; or etc, etc.

 

And this is all perfectly valid. It's generally what we do. The Earth-Sun distance we "observe" is made from the Earth's FOR and we (arbitrarily) choose that as the "official" distance. And it becomes "well-known" and "standard" as you have said. Nothing wrong with any of that.

 

But there is no ONE, uniquely correct, absolutely correct distance.

 

All distances must be observed.

All distances must be measured.

All measurements must be made from some FOR -- one or another.

And NO frame of reference is "privileged" over the others, in the sense that it enables observations that are more correct than observations made from other FORs.

 

This leads to the conclusion that there is no "actual distance" in the sense that it is the one and only

uniquely correct, absolutely correct distance.

 

:)

 

Then... all of the "standard measures of distance", as in my list for this solar system above, are actual, objective distances. Regardless of point of view (from earth, sun or other planets.) The "measuring rod" of lightspeed as applied to all above distances (say, by a virtual, transcendental, cosmic observer) will remain exactly as listed above. To clarify... I am not speaking relativistically of the "measuring rod of lightspeed" as objects are observed from various local perspectives.... (Please indulge the experiment)... but the *actual* distance light travels in a given precise time interval between each of the bodies in the list above... independent of who sees what from where and when relative to each observer.

 

No. In every frame of reference light travels the same distance per second, but distances and seconds themselves change from reference frame to reference frame. This means light takes less time to travel between objects for one frame as it would for another. For the clock moving relative to the earth clock, a beam of light can go from earth to the sun in just a few seconds. Lightspeed is not an objective measure of distance *as you describe it*.

 

What this all boils down to—if you want the earth to be 150 million km from the sun in your transcendent perspective then you need to explain how it oddly exactly coincides with what we earthlings happen to measure. If you want to declare that everthing in the present is simultaneous everywhere (as you've said) then you need to say what reference frame all those things are simultaneous in otherwise it just looks like you have no idea what modern philosophy of space and time looks like.

 

Space and time are real. They exist in the same way momentum exists. This does not, however, mean that an object has one value of length any more than it means a bowling ball has one value of momentum. The value of momentum depends on the frame from which you are describing it. Space and time are the same way.

 

~modest

[Pyrotex]

Watcher,

I think my reply to Pyrotex, just posted will also address much of your last post....Cosmos "gives up" nothing in the absence of measurement, by any life-form anywhere....

Michael,

I'm sorry, but it is so damned hard to understand what you are really getting at. I seriously wonder if you really know what "ontological" really means, or if you've just been to a lot of Forum Seminars lately.

 

But here is my best try at rephrasing what you may be asking:

 

Can we say that between two points in the Universe, A and B, ignoring all frames of reference, there "exists" a unique minimum distance between them that can be said to be the "actual" distance between them, irrespective of any observers, or even in the total absence of observers?

 

There IS an answer to this question, but I'm not sure you're gonna like it.

 

Yes, Michael, if that's what you're trying to say, then you can say that.

And if you're charming and persuasive enough, you can even get us to agree with you.

 

But there is NOTHING MORE you can say about points A or B or the distance between them. Nothing. No assumptions, no conclusions. You can't use that distance as evidence for anything else. Without any observations at all, the points themselves and any distance there may be between them lies in the realm of idle speculation. Or philosophy.

 

But you can say anything you like about their "independent existence".

 

"Points A and B. They're Out There!"

[Cue the theme from The Twilight Zone]