Frame of Reference as Subject in Subjective Idealism

[tar]

Iggy,

 

Thanks again for #109. I read it through a few time. Get hung up around the same time each time. Will have to read through it again a few times.

 

I don't like the "now" line at tzero. That looks too much like the universal now we have been talking about. That is not an empirically observable moment, from ANY reference frame. And it takes a God's eye, or at least an imaginary eye that "sees" instantly, events separated by lightseconds of distance "at the same time". If this imaginary view of "now" is to be considered "real", it can only be sensibly understood as what will be "real" seconds later. And I am left with the same question. Which "now" are we talking about?

 

There are a number of ways one can look at a moment, in both duration and in size. After all, from the point of view of an epiphany I had 30 years ago "life on Earth, from the first organic molecule till an evolved forest of Oak, and Maple and Pine, is but a fleeting instant in the vastness of time and space".

 

I wonder sometimes about how "scale" effects this discussion. We have no problem considering something we can hold between our hands, being in one place, at one time. But there is some fraction of a lightnanosecond's distance between our right and left hands.

 

At any grain size, from a quark to a universe, we can consider the whole thing contained in one thought (properly scaled). Existing at a properly sized "here" and a properly sized "now".

 

Not empirically proper to consider ANY two separated events "simultaneous". By definition they are separated. Either by time, or by the time light takes to go the distance.

 

Regards, TAR2

[Iggy]

I don't like the "now" line at tzero. That looks too much like the universal now we have been talking about.

The reason it is not universal is that it is not shared by multiple frames of reference. Two people who have a relative velocity do not agree on which events happen 'right now'.

 

That is not an empirically observable moment, from ANY reference frame. And it takes a God's eye, or at least an imaginary eye that "sees" instantly, events separated by lightseconds of distance "at the same time". If this imaginary view of "now" is to be considered "real", it can only be sensibly understood as what will be "real" seconds later. And I am left with the same question. Which "now" are we talking about?

I understand what you mean. I saw you talking about it earlier.

 

All of the events that happen 'right now' or 'at the present instant' happen simultaneously -- or at the same time. Saying "right now" is another way of saying "at this time". If the current time is 4:00 am then all the events which happen 'right now' happen at 4:00 am.

 

You are, of course, correct -- a person will not see all of those events straight away. An event that is one light-second away will take one second before it is seen. An event that's one light-year away takes a year before it is seen. This is not a problem because 1: light has a finite speed, and 2: we are talking about when events happen, not when they are observed.

 

In fact, these are two separate events we're talking about. When a star goes supernova several light-years away that is an event. When humans observe the supernova that is another event. The supernova event and the observation event are separated by space and time. They are different dots on a space-time diagram.

 

Not empirically proper to consider ANY two separated events "simultaneous". By definition they are separated. Either by time, or by the time light takes to go the distance.

In relativity "simultaneous" refers to time. Two events that are simultaneous will be seen by an observer half way between them at the same time. This is the way Einstein defined the term. It is also, by the way, the way St. Augustine defined the term fifteen hundred years ago. He said that two women who are separated by a great deal of distance would have given birth simultaneously if messengers sent out at the moment of delivery met up midway between the two women.

[owl]

swansont:

Relativity predicts that you will get different measurements in

different frames, and also tells us that you cannot tell which frame is preferred. If you want to have a preferred frame for objective idealism, you have to give an objective way of telling everyone how they can tell if they are in the frame that corresponds to the objective reality. How do you do that?

 

First, I advocate objective realism, not “objective idealism” (which is an oxymoron.) I advocate an at rest (with what is measured) frame because it yields a description of earth, for instance, that does not champion the obvious absurdity, defying all known earth science, that it is "in reality" squished nearly flat as seen from the extreme FOR we have been using as an example. If the result is totally absurd (and we all know better), the assumption (no preferred frame... as seen passing by at near lightspeed is equally accurate)) is probably wrong. And no experiments have shown large scale length contraction to be valid.

 

Does light go straight in space where no masses are nearby and bend when it goes around a massive object?

 

I'll spare you the effort: the answer to this is yes.

 

Agreed. But light has momentum that acts like mass (making lasers recoil, "solar wind" (?), increased inertia in the "box of mirrors" experiment...) So mass can bend the path of light without making something out of nothing, i.e., "curved space."

 

You could also say that planets orbit the sun in straight lines through curved space... but who believes that planets' orbits are straight lines unless straight=curved (in the spacetime "model") and the words are meaningless?

 

Can you model this and other gravitational effects geometrically? Again, yes.

 

Yes. But ontology examines the leap from models to that which they are modeling.

 

There is plenty of evidence which shows GR to be an accurate description of how nature behaves. So clearly, the spacetime that GR describes is indeed curved.

etc... etc...

See my last sentence above and my recent ontology of space and time. No need for endless repetition if you have no interest in or knowledge of what ontology is.

If you could muster the interest, you could examine your above assertion in light of all quotes in the Ontology of Spacetime thread, and all referenced material not quoted. If space is empty volume and time is event duration ("tick, tick")... then "they" do not combine into the famous "fabric of spacetime," and nothing "curves" but the model.

[tar]

Iggy,

 

I understand the concept that Einstein was talking about with similtaneity, and the important role that light speed plays in the determination of "distance" in both space and time. I go by it.

 

But there is a "reference" point, a viewer we use, to concieve of the observer "inbetween" that sees the two simultaneous moments, and this "viewer", that "sees" the inbetween observer IS NOT CONSTRAINED BY THE SPEED OF LIGHT. This viewer can be at both ends and in the middle, AT THE SAME TIME. This is not "possible", it can only be imagined, and only "proved out" by repeated experimentation, and memory of what was the case, before.

 

This is why I am leaning in the direction of there being two types of NOWs. One actual, and the other imagined.

Both however, real, in that the "imagined" one will indeed prove out to be the case.

 

More than likely Einstein and the other geniuses that have been cogitating on this for the last century, have indeed "figured" it out, put it down in writing and formulae, and tested it all out, to indeed "be the case".

 

What I object to is calling the view of this viewer, that sees both ends and the middle at the same time, the "real" objective truth. When this view, is actually the "imagined" one.

 

Regards, TAR2

[swansont]

swansont:

 

 

First, I advocate objective realism, not “objective idealism” (which is an oxymoron.) I advocate an at rest (with what is measured) frame because it yields a description of earth, for instance, that does not champion the obvious absurdity, defying all known earth science, that it is "in reality" squished nearly flat as seen from the extreme FOR we have been using as an example. If the result is totally absurd (and we all know better), the assumption (no preferred frame... as seen passing by at near lightspeed is equally accurate)) is probably wrong. And no experiments have shown large scale length contraction to be valid.

 

 

 

Agreed. But light has momentum that acts like mass (making lasers recoil, "solar wind" (?), increased inertia in the "box of mirrors" experiment...) So mass can bend the path of light without making something out of nothing, i.e., "curved space."

 

You could also say that planets orbit the sun in straight lines through curved space... but who believes that planets' orbits are straight lines unless straight=curved (in the spacetime "model") and the words are meaningless?

 

 

 

Yes. But ontology examines the leap from models to that which they are modeling.

 

 

etc... etc...

See my last sentence above and my recent ontology of space and time. No need for endless repetition if you have no interest in or knowledge of what ontology is.

If you could muster the interest, you could examine your above assertion in light of all quotes in the Ontology of Spacetime thread, and all referenced material not quoted. If space is empty volume and time is event duration ("tick, tick")... then "they" do not combine into the famous "fabric of spacetime," and nothing "curves" but the model.

 

I can't help but notice that you failed to answer the question I asked: How does one show a valid scientific model to be "truth" or not? You keep avoiding this. You keep saying that things related to relativity are absurd, but that seems to be the extent of your analysis. It's devoid of any substance. You offer no way to actually test your position. "I'm obviously right because you can't prove me wrong" is a failure of fundamental logic.

[Iggy]

This is why I am leaning in the direction of there being two types of NOWs. One actual, and the other imagined.

Both however, real, in that the "imagined" one will indeed prove out to be the case.

Yeah, I understand what you're saying. One set of events are observed now and the other happen now. The first relativity calls your past light cone and the second it calls the present instant.

 

If you say (or anyone says) that reality is dependent on frames of reference, you throw philosophical realism out and subscribe to a form of idealism in which things ARE as they are seen, having no intrinsic properties of their own, independent of frames of reference.

By your silence I assume I'm correct -- because you say velocity depends on reference frame you have thrown out philosophical realism and subscribed to a form of idealism in which objects have no intrinsic properties.

[tar]

The first relativity calls your past light cone and the second it calls the present instant.

 

 

So if what we see happening on Alpha Centuri, now, is our past light cone, and what is happening "now" on Alpha Centuri is happening in our present instant, what of the 4.5 years worth of "events" that are currently in transit?

 

What does relativity call those moments?

 

Regards, TAR2

[owl]

swansont:

I can't help but notice that you failed to answer the question I asked: How does one show a valid scientific model to be "truth" or not? You keep avoiding this. You keep saying that things related to relativity are absurd, but that seems to be the extent of your analysis. It's devoid of any substance. You offer no way to actually test your position. "I'm obviously right because you can't prove me wrong" is a failure of fundamental logic.

 

Earth can not be both nearly spherical and very oblate. It must be one or the other. Are you with me so far? Which is it? If length contraction is a "valid scientific model", then it all depends on how you look at it... which is idealism and you deny the above "air tight" logic.

I can't help but notice that you constantly dodge the challenge to show experimental evidence that length contraction is valid outside the particle accelerator, yet you turn it around as if it is up to me to disprove length contraction applied to earth.

 

Iggy, 124: “Can’t answer?” Did already, many times.

131:

By your silence I assume I'm correct -- because you say velocity depends on reference frame you have thrown out philosophical realism and subscribed to a form of idealism in which objects have no intrinsic properties.

 

I’ve said the following many times: That everything is moving everywhere, so velocity requires a specific reference, i.e., relative to what? I argue that at rest (no relative velocity between observer and observed) is the preferred frame for objective accuracy of measurement.... that “it all depends on frame of reference” is idealism, not realism, in which things are as they are, independent of perspective. We investigate "reality" by minimizing unknown variables, like extreme hypothetical frames from which to measure.

 

My silence has been in keeping with the following, which you have ignored in order to falsely assume the above:

From my post 117:

Your continuing attempts to distort what I say will continue to fail, but I will not continue to reply.

(This exception for clarification only.)

 

Tar,

Your conversation with Iggy on presentism/simultenaity (what “now” means) belongs in the Ontology of Time thread.

[Cap'n Refsmmat]

Earth can not be both nearly spherical and very oblate.

That is an assumption with no basis in reality.

 

I can't help but notice that you constantly dodge the challenge to show experimental evidence that length contraction is valid outside the particle accelerator, yet you turn it around as if it is up to me to disprove length contraction applied to earth.

As I understand it, length contraction is a logically necessary consequence of the universally constant speed of light. (The speed of light is constant as measured in any reference frame, and this has been verified repeatedly.) The constant speed of light requires that lengths contract to make physical sense.

 

There is also an experimental confirmation of length contraction based on the flow of currents through macroscopic wires at relatively slow speeds.

 

Any good book on special relativity will explain how length contraction can be derived from the postulate that the speed of light is a constant, along with the postulate that laws of physics apply in all inertial reference frames.

[swansont]

Earth can not be both nearly spherical and very oblate. It must be one or the other. Are you with me so far? Which is it? If length contraction is a "valid scientific model", then it all depends on how you look at it... which is idealism and you deny the above "air tight" logic.

I can't help but notice that you constantly dodge the challenge to show experimental evidence that length contraction is valid outside the particle accelerator, yet you turn it around as if it is up to me to disprove length contraction applied to earth.

 

As I pointed out before, in acknowledging that the experiment has not been done, insisting on a specific bit of evidence is intellectually dishonest. It forces you into a position that no science is valid except the specific experiments that have been done. Hence my repetition of the example of gravity. You can't believe gravity works, because it has not been tested everywhere, and almost certainly not where you spend most of your time. You must regard your computer as a magic box, because the laws governing electronics and quantum mechanics that determine its operation were not tested on your machine.

 

Science doesn't work that way. Unless that specific bit of evidence is required in order to show that the theory is correct, you cannot demand it as a requirement to accept the theory. It's a form of the fallacy of moving the goal posts. An experiment that has not been done is not evidence against a theory.

 

Because relativity has a large body of evidence confirming it, it is up to you to disprove length contraction, though it need not be of the earth. It has to fail, though, and you have to show that it does. It is your burden of proof.

[tar]

Tar,

Your conversation with Iggy on presentism/simultenaity (what “now” means) belongs in the Ontology of Time thread.

 

Owl,

 

Perhaps, but my mind is concerned with the fact that what we know to be the case, is an imagined condition, based on past "actual" experience, that we predict will be the case in the future. So what we have "learned" is applied to our "predictions".

 

Subjectivity and Objectivity are interwoven in this consideration of "now" as deeply as it is for the "shape of the Earth".

 

Perhaps, since its your thread, I should listen to you. But I believe, that if you consider it a piece of the investigation of subjectivity and objectivity, you might entertain it here.

 

Regards, TAR2

[owl]

So, as per thread title:

Is there an objective world/cosmos with intrinsic properties independent of observation/measurement (realism) or does reality depend on how things are perceived (i.e., from different frames of reference?)

me:

Earth can not be both nearly spherical and very oblate.

Cap 'n R:

That is an assumption with no basis in reality.

 

So, as per idealism, you assert that earth can be both nearly spherical and very oblate, depending on how you look at it (from different frames of reference), denying realism's "objective world/cosmos with intrinsic properties independent of observation/measurement."

 

This is nonsense, but it does show clearly, without a doubt where the length contraction aspect of relativity falls in the title challenge.

I am done.

 

Swansont from post 131:

You never commented on whether you had experimentally verified that gravity exists in your living room.

 

From post 135:

Hence my repetition of the example of gravity. You can't believe gravity works, because it has not been tested everywhere, and almost certainly not where you spend most of your time

.

 

More nonsense, times two. I ,like everyone else, stick to the ground as I walk and, as already pointed out, to my living room floor. Apples fall from trees to the ground today as in Newton's day. What a bogus challenge!

Btw, I understand the classical Einsteinian principle or thought experiment that one in an enclosed box (or whatever) can not know if he is on earth sticking to the floor because of earth's gravity or being accelerated through space in the "up through the ceiling" direction. So, If this is your point, ... I do not live in an enclosed box.

[Cap'n Refsmmat]

So, as per idealism, you assert that earth can be both nearly spherical and very oblate, depending on how you look at it (from different frames of reference), denying realism's "objective world/cosmos with intrinsic properties independent of observation/measurement."

You make a fatal assumption that reality is wholly three-dimensional. The three-dimensional shapes of objects change depending on which slice of four-dimensional reality they are contained within; the Lorentz transformations of relativity reflect a rotation in four-dimensional space.

 

This would seem to imply the opposite of subjective idealism: that reality is objective, but we perceive different slices of it.

[swansont]

More nonsense, times two. I ,like everyone else, stick to the ground as I walk and, as already pointed out, to my living room floor. Apples fall from trees to the ground today as in Newton's day. What a bogus challenge!

Btw, I understand the classical Einsteinian principle or thought experiment that one in an enclosed box (or whatever) can not know if he is on earth sticking to the floor because of earth's gravity or being accelerated through space in the "up through the ceiling" direction. So, If this is your point, ... I do not live in an enclosed box.

 

Really? You've done the experiment to show that it's gravity, and not some other mysterious effect? Why should you get to dismiss length contraction, because some specific experiment has not been done, but I can't dismiss gravity for the exact same reason?

[Iggy]

So if what we see happening on Alpha Centuri, now, is our past light cone, and what is happening "now" on Alpha Centuri is happening in our present instant, what of the 4.5 years worth of "events" that are currently in transit?

 

What does relativity call those moments?

 

Regards, TAR2

It may be important to note that the events themselves are not in transit. The light emanating from them is.

 

I don't know of any specific label to give the category of events you outline. They are events that were in your present instant at some time in the past.... which is, I suppose, a drawn out way of saying that they are in the past. Those events could also, interestingly enough, be in your present instant again if you took on a sufficient velocity away from Alpha Centauri. You could google "Rietdijk–Putnam argument" if that sounds of interest. I share Owl's concern, however, that we've gotten a bit beyond the topic at hand.

 

Earth can not be both nearly spherical and very oblate. It must be one or the other. Are you with me so far? Which is it?...

 

...everything is moving everywhere, so velocity requires a specific reference, i.e., relative to what?

I understand your position. There is no point in repeating it.

 

You say that velocity is relative to reference frame. I assume you would say the same thing of momentum and a few other frame-dependent properties. But, distance and duration, you say, can't be relative. This begs a very obvious question...

 

On what grounds do you choose which properties can and cannot be relative? Why does it imply subjective idealism to say "distance depends on frame of reference" and it does not imply subjective idealism to say "velocity depends on frame of reference"?

[jspsfx]

It may be important to note that the events themselves are not in transit. The light emanating from them is.

 

I don't know of any specific label to give the category of events you outline. They are events that were in your present instant at some time in the past.... which is, I suppose, a drawn out way of saying that they are in the past. Those events could also, interestingly enough, be in your present instant again if you took on a sufficient velocity away from Alpha Centauri. You could google "Rietdijk–Putnam argument" if that sounds of interest. I share Owl's concern, however, that we've gotten a bit beyond the topic at hand.

 

Yes. Yes. Events are interpreted as information; all things observed are recorded post occurence in regards to the spatial coordinates of said event. This is the nature of time and why we must create evaluations of past, present, and future. To be human is to be subjective.

 

In reality, all measurements concocted of existence will inherently derive from FOR. Science is the greatest objective description of being we have at this point IMHO.

[owl]

I'll pretend this is the ontology of time thread. ("My three threads* are naturally interwoven anyway. This and ontology of both time and spacetime.)

It may or may not be helpful to ask how one conceives of a boundary around "now" as a local present, as distinguished from a universal present without such a local boundary.

 

In other words we all know that it takes time for light to travel through space to carry images and information... simple signal delay on all scales. But, of course (repeating) now IS now here and on the sun (and everywhere, if no "now boundaries"), even though obviously we will not see sun's now for over eight more minutes.

 

The same can be said for time, if we set aside the familiar model of "time cones" for "now." Granting signal delay, what is the argument against presentism as "The present IS present everywhere?"

 

jspfsx:

 

In reality, all measurements concocted of existence will inherently derive from FOR. Science is the greatest objective description of being we have at this point IMHO.

 

So, do you believe that earth IS a very oblate spheroid "for" the above extreme FOR, and earth IS nearly spherical "for" those seeing it (and living on it) in an at-rest frame?

Can it be either or both, depending on how you see it? If so, in what way is "earth IS how you see it" NOT subjective idealism with FOR as subject?

 

Iggy:

On what grounds do you choose which properties can and cannot be relative? Why does it imply subjective idealism to say "distance depends on frame of reference" and it does not imply subjective idealism to say "velocity depends on frame of reference"?

 

On the grounds that everything is moving and velocity requires specificity as to "moving how fast relative to what."(as I've said a few time already.)

Whereas, (as I've also repeated many times) realism posits that objects have intrinsic properties like shape, size, density, rigidity, etc., independently of how (or if) they are seen from whatever FOR.

 

Likewise, the distance between bodies, is also intrinsic as above, depending only on their movement relative to each other (closer or further away), i.e., one AU or about 93 million miles between earth and sun. This does not change just because a high speed traveler might see that distance as, say 1/8th the standard AU. That would mean that perception creates reality, the idealist belief, contradicting the realism that insists that the only variation in that distance is due to the irregularity of the elliptical orbit, sometimes closer, sometimes further.

Cap 'n R:

You make a fatal assumption that reality is wholly three-dimensional. The three-dimensional shapes of objects change depending on which slice of four-dimensional reality they are contained within; the Lorentz transformations of relativity reflect a rotation in four-dimensional space.

 

This would seem to imply the opposite of subjective idealism: that reality is objective, but we perceive different slices of it.

 

Referring to my recent comments on the non-Euclidean claim of four spatial dimensions, can you explain what the fourth axis of space is beyond the well known three, the line, plane and volume?

If the fourth is just the time factor (elapsed time during movement of objects), then how does that create the "four dimensional slices of reality," model which you like so well?

 

You said that earth's shape does not change (radically.) Yet it IS nearly flat as seen from one FOR and nearly spherical from the at rest FOR.

Now you say that "The three-dimensional shapes of objects change..." by adding a "weird" (previous post) fourth dimension. This looks to me like either a blatant contradiction or creation of a metaphysical mystery dimension out of nothing/nowhere... like the claim of seven extra dimensions (11 total) in M-Theory. How is your fourth dimension different than those seven, with no basis at all in empirical science?

[tar]

Iggy,

 

Those events could also, interestingly enough, be in your present instant again if you took on a sufficient velocity away from Alpha Centauri.

 

I don't think that is true. You cannot outrace light.

 

Regards, TAR2

[Iggy]

In other words we all know that it takes time for light to travel through space to carry images and information... simple signal delay on all scales. But, of course (repeating) now IS now here and on the sun (and everywhere, if no "now boundaries"), even though obviously we will not see sun's now for over eight more minutes.

Nothing of that is inconsistent with special relativity.

The same can be said for time, if we set aside the familiar model of "time cones" for "now." Granting signal delay, what is the argument against presentism as "The present IS present everywhere?"

That is not presentism.

 

On what grounds do you choose which properties can and cannot be relative? Why does it imply subjective idealism to say "distance depends on frame of reference" and it does not imply subjective idealism to say "velocity depends on frame of reference"?

On the grounds that everything is moving and velocity requires specificity as to "moving how fast relative to what."(as I've said a few time already.)

Whereas, (as I've also repeated many times) realism posits that objects have intrinsic properties like shape, size, density, rigidity, etc., independently of how (or if) they are seen from whatever FOR.

 

Likewise, the distance between bodies, is also intrinsic as above, depending only on their movement relative to each other (closer or further away), i.e., one AU or about 93 million miles between earth and sun. This does not change just because a high speed traveler might see that distance as, say 1/8th the standard AU. That would mean that perception creates reality, the idealist belief, contradicting the realism that insists that the only variation in that distance is due to the irregularity of the elliptical orbit, sometimes closer, sometimes further.

It is difficult to tell if you are purposefully not answering or if you do not understand what I am asking.

 

Let's try this. Get a piece of paper and draw a line down its center. Label the left side of the paper "constant, frame independent, intrinsic properties". Label the right side "relative, frame dependent, non-intrinsic properties".

 

Now write these words on the page wherever you think they belong... on the left side or the right side: distance, velocity, size, duration, color, momentum.

 

The question is *how did you decide* where to put the words. In each case, how was the decision made?

 

If you think that realism demands that certain words go on the left or right then, why? Why do you think realism demands velocity on the right, but demands duration on the left?

 

So far all you have said is that velocity is relative because velocity is relative and distance is constant because distance is constant. That doesn't get us anywhere.

 

I don't think that is true. You cannot outrace light.

According to SR and the thought experiment you laid out you wouldn't have to.

[owl]

Backtracking to a comment by Cap 'n R last Friday:

 

Cap ‘n R:

The constant speed of light requires that lengths contract to make physical sense.

 

 

Philosophically speaking, given a choice between the constant speed of light (with plenty of evidence for it) and the constant shape/length of 'immutable' solid objects like earth and solid rods, (with overwhelming evidence for them staying solid, not morphing out of shape or changing lengths) why is it that constant ‘C’ is assumed to be correct and immutable objects are actually mutable? How does it “make physical sense” that solid objects have no intrinsically stable properties, and rather, that light, relatively quite insubstantial, has “immutable” (constant) velocity.

Just asking.

 

Iggy, I give up yet again on explaining realism, as knowing that objects have intrinsic properties vs the idealism of "things ARE as they appear" from different frames of reference.

Your hand in front of your face does not in fact change shape and characteristics as you view the palm and then the back. I'm done arguing with you about it.

[Cap'n Refsmmat]

Because constant c is one of the most-tested predictions of physics.

 

http://math.ucr.edu/home/baez/physics/Relativity/SR/experiments.html#round-trip_tests

[swansont]

Philosophically speaking, given a choice between the constant speed of light (with plenty of evidence for it) and the constant shape/length of 'immutable' solid objects like earth and solid rods, (with overwhelming evidence for them staying solid, not morphing out of shape or changing lengths) why is it that constant ‘C’ is assumed to be correct and immutable objects are actually mutable? How does it “make physical sense” that solid objects have no intrinsically stable properties, and rather, that light, relatively quite insubstantial, has “immutable” (constant) velocity.

Just asking.

1. My radio works when I'm moving — that requires a constant c. Constant c is not limited to relativity. Maxwell's equations — the basis for electrodynamics — contains it. Relativity is an extension that applies the concept to kinematics.

 

2. Your scenario is a false dichotomy, because relativity does NOT predict that objects "morph". The have different lengths in different frames of reference. Those are two very different statements.

[Iggy]

Iggy, I give up yet again on explaining realism, as knowing that objects have intrinsic properties vs the idealism of "things ARE as they appear" from different frames of reference.

Your hand in front of your face does not in fact change shape and characteristics as you view the palm and then the back. I'm done arguing with you about it.

The question was, how do you decide if a property is intrinsic or not. Why is duration intrinsic and velocity not?

 

You keep saying that's the way the world is and that's the way it has to be. Have you asked yourself why?

[owl]

Because constant c is one of the most-tested predictions of physics.

How does this address my "philosophically speaking" paragraph above? How is length contraction, derived from constant 'C', "better tested" than earth science facts?

The earth; size (about 8000mi diameter) and shape (nearly spherical) is probably the most precisely measured and thoroughly studied object ever. It is rigid. It doesn't morph. It does not have a 1000 mile diameter. These are facts. How does constant 'C' invalidate them?... By a dictum that insists "all frames of reference are equally valid." Isn't "under a microscope" a more valid way to study the factual properties of a microscopic object than with it flying by at near light speed? (Ans: Yes.)

(Argument for "at rest" frame with what is measured giving more valid results.)

I am not arguing against the constant value of 'C', just the assumptions and conclusions of length contraction derived from it which deny the above facts.

 

swansont:

2. Your scenario is a false dichotomy, because relativity does NOT predict that objects "morph". The have different lengths in different frames of reference.

Those are two very different statements.

 

We agree that objects don’t change shape and size (in the context of length contraction.) But there is a big difference between my claim that they just look different from different frames of reference and your claim that they are different, "have different lengths in different frames of reference."

 

Case in point, using absolutely airtight logic:

If earth does not morph, it cannot change from spherical to very oblate. It must be one or the other, i.e., it can not be both. It's diameter can not be "different lengths."

 

You guys constantly avoid the thread title question.

“For” a muon, you say the atmosphere is way less than 200 miles thick. This is based on the following faulty logic:

We "know” the above because incoming muons “live” longer and travel further than “expected” based on observation of lab muons, so the distance traveled must be shorter than the established depth of atmosphere. Some logic!

“For” the (overworked) high speed traveler through our solar system, an AU is about 11 million miles rather than the well established 93 million miles, and earth, as above, has a diameter of about 1000 miles rather than the at-rest frame 8000 or so. “For the traveler.”

 

“For” the same traveler passing a meter rod, it is about 12 cm long. But, of course the meter rod doesn’t change length, nor does earth’s diameter nor the earth-sun distance.

 

All of the above perfectly fits the description of philosophical subjective* idealism, transposing "frame of reference" ("for" whatever) for "subjective." The latter says "The world is as it is perceived. It has no intrinsic properties independent of perception/frames of reference." Philosophical realism says it does.

*("Subject" need not be a person but can be just an abstract point of view.)

 

Iggy:

The question was, how do you decide if a property is intrinsic or not. Why is duration intrinsic and velocity not?

 

You keep saying that's the way the world is and that's the way it has to be. Have you asked yourself why?

 

We look at each situation in all its particulars and apply the scientific method. Your hand in front of your face was an obvious illustration. How do you "know" it is not just a palm when you can't see the back?

Because, ever since we were born we have seen it from all angles and *know* it as a whole hand with all its "intrinsic properties" even when we only see one side or the other. Apply that on all scales to all "known objects." Of course, the more familiar we are with a given object the better, because we have memory and previous records as well as immediate observation as part of empirical science.

 

Duration can be the time between the "ticks" of a clock (or "clicks" of a stopwatch) or any elapsed time of any physical process under consideration. The physical objects have intrinsic properties, as belabored above, and duration is the concept explained yet again above.

As objects move we can only assign velocity relative to other objects, because that is the meaning of velocity. A car's velocity designated as 60 mph is relative to the road, but a mile-marker on the road is spinning at over 1000 mph relative to the center of earth, and the whole earth is going whatever velocity in orbit around (relative to) the sun, which has whatever velocity relative to the center of the galaxy... etc., etc... to belabor the obvious, yet again.

Edited August 17, 2011 by owl

[Cap'n Refsmmat]

How does this address my "philosophically speaking" paragraph above? How is length contraction, derived from constant 'C', "better tested" than earth science facts?

The earth; size (about 8000mi diameter) and shape (nearly spherical) is probably the most precisely measured and thoroughly studied object ever. It is rigid. It doesn't morph. It does not have a 1000 mile diameter. These are facts. How does constant 'C' invalidate them?... By a dictum that insists "all frames of reference are equally valid." Isn't "under a microscope" a more valid way to study the factual properties of a microscopic object than with it flying by at near light speed? (Ans: Yes.)

(Argument for "at rest" frame with what is measured giving more valid results.)

I am not arguing against the constant value of 'C', just the assumptions and conclusions of length contraction derived from it which deny the above facts.

A constant c does not invalidate any claims of Earth science, and Earth science's many tests and observations are not relevant. As I posted some days ago:

 

In the Earth's reference frame, the predictions of:

 

• Earth science: Nearly spherical Earth.
  
• Newtonian mechanics: Nearly spherical Earth.
  
• Relativity: Nearly spherical Earth.
  

 

So how do the observations of Earth science contradict relativity?

 

One might extend that with the predictions of each in a reference frame moving very fast relative to Earth:

 

• Earth science: Dunno, never looked at Earth while moving fast.
  
• Newtonian mechanics: Nearly spherical Earth.
  
• Relativity: Oblate spheroid Earth.