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Posted

You speak of "hypervolume" as if you have a clue what it means. To what dimension does it refer beyond 3-d space/volume?

 

By hyper-volume I mean volume with an extra degree of freedom, but like you, I'm not fluent in math so there are probably better definitions .

 

A curved line on a basketball surface (3-d, not a flat plane) is a 3-d curved line. If you ignore the third dimension, you are confined to a 2-d surface, a flat plane... but why ignore the fact that the ball/sphere is a 3-d object?

I'm not ignoring it, I'm saying it's necessary to be 3-d to see 2-d geodesics as curves.

Posted

And I have evidence that it does*, all consistent with relativity. But your objection to clocks measuring time is that clocks are simply "engineered devices". So, given that both are concepts, how is it that a meter stick can measure length, while a clock does not measure time?

 

"It does" refers to this exchange:

You:

“Doesn't a meter stick — a self-contained device — have a length, all by itself?”

me:

Yes, it does. You are the one claiming that it's length varies with frame of reference.

You:

If you acknowledge that there is no force involved, why did you bring rigidity into the discussion?

 

You claim length varies with frame. Diameter of Earth is its length. It's rigidity is an argument for it having an intrinsic shape, not malleable or changing with your length contraction scenario.

 

The shape you measure depends on the frame of reference you are in.

 

That is your idealism. Earth's shape does not change even if your measurement of it from the well worn extreme frame varies.

 

This is not about measurement error, a surprising mistake for someone who has taught these concepts — an expert — to make.

 

No it's not. I have acknowledged many times that the Lorentz transformation formula 'transforms' the possibility of a silly looking squished Earth back to its well known shape. You and others insist that it has no true shape, all shapes as seen from extreme frames being equally valid. Funny you have missed that point after so many repetitions.

 

As I stated, the contradiction logically proves that there cannot be a preferred frame of reference.

 

What contradiction?

You deny realism and contend that reality, including Earth's shape, depends on the frame of reference from which it is seen. This proves that your science is based on idealism in denial that cosmos exists and has properties independent of observation and measurement. (X well over a hundred on that philosophical point.)

 

Why are you changing the conditions of the example (again)? I stated that the clock is at rest, and the identical physical processes take place in different frames. And yet the do not begin and end simultaneously. How does realism explain this — isn't event duration an intrinsic property of a physical process?

 

As long as frames of reference dictate your reality, there is no communication between us on this point. We are way beyond clarity on which example is an argument for what point here.

"Identical physical processes?" Clocks slow down. "Time" is not a process that slows down. Clocks' rates of oscillation vary.

The elapsed time for my dropped ball does not vary, just because two clocks in different frames will have "clocked" the event duration differently. Address that.

 

"time dilates" is a figurative expression that apparently is lost on you. In physics, time is a legitimate variable. It, like length, is not invariant. But neither is a real, physical thing. The so-called reification happens when one takes literally that which is meant figuratively. I've given you the equation before, but you turned your nose up at it and never explained how it reified time.

 

I've explained before that the math is not the explanation of what time dilation means, and that I don't do math. So you go ahead and say... 'see here... the math tells us that time dilates and length contracts.' No, it doesn't.

If you agree that "time dilation" simply means that clocks slow down at high speed, etc., then, fine. No explanation of how that works, but... fine. Then you are not allowed the possibility of 'time travel' either if you have repented from the reification of time. Also then we both know that clocks tick as regularly as we can design them to tick and we can compare ticks to other events and say, so much time elapsed, and call it a measurement. But if clocks differ on clocking the same event... they require adjustment... which we've discussed in detail re GPS etc.

 

[math]\Delta{t'} = \frac{\Delta{t}}{\sqrt{1-\frac{v^2}{c^2}}}[/math]

 

How does this reify time? This is the actual physics. Not the words.

 

Wow! "The actual physics!" No need for mere words to make sense and meaning of it. No need for ontology of time. (See above.) It is what clocks measure!

 

Answering a question, albeit not in a way that agrees with your philosophy, is not running and hiding. But since you seem to have missed it, the curvature is in the geometry we use to describe the 4D space.

 

I've challenged you several times to critique Ross' piece which examines the ontology of your 4D space in depth. I've been explaining the geometry of 3-d space and time to moth, ydoaPs and others here, and there is no fourth dimension of space. If you think there is, explain it. Asserting it as a given does not cut it... not an argument for it.

 

Why does realism not insist on physical processes staying the same when observed from a different frame of reference? i.e. we aren't discussing environmental effects here — only the observer's frame. Isn't that the essence of realism? If that property isn't the same in all frames then realism isn't an absolute, now is it? How can you insist on any other property being the same in all frames?

 

You deny realism. Realism states that things are as they are, not depending on your all-important frames of reference from which they are seen and measured.

 

"...only the observer's frame. Isn't that the essence of realism? "

NO! Just the opposite! How many times have I said that the world doesn't care how we look at it? It is as it is regardless of that. That leaves science the task of always finding the best way to look at whatever is being measured and observed... and, yes, there are better and worse ways to do that.

And what about the other properties that you keep ignoring when I bring them up? Why don;t the stay the same in other frames of reference? Does realism only apply to length?

See above reiteration. If we disagree on Earth having a true, intrinsic shape and on the distance (length) to the Sun hanging right around 93 million miles... not getting way shorter (contracted) as seen from... extreme frames... then there is no use for or need of further, more subtle examples.

 

Yes, scientists are complete morons and never thought of this. Never tested it many, many times to see if there was a force that was the culprit.

 

So you are going to stick with "relativity makes it happen" and think that you have explained it? Oh well... And how about that gravity 'explanation.' Curved spacetime covers it too, even though it is anybody's guess what it is or what the word means, much less how it works. It's all in the math. So is the quantum gravity version, but quite a different theory. You have very successfully avoided that challenge too.

Posted

"It does" refers to this exchange:

 

 

You claim length varies with frame. Diameter of Earth is its length. It's rigidity is an argument for it having an intrinsic shape, not malleable or changing with your length contraction scenario.

 

And I have presented you with evidence of length contraction. You have not rebutted it, because you are not qualified to evaluate it, by your own admission.

 

 

No it's not. I have acknowledged many times that the Lorentz transformation formula 'transforms' the possibility of a silly looking squished Earth back to its well known shape. You and others insist that it has no true shape, all shapes as seen from extreme frames being equally valid. Funny you have missed that point after so many repetitions.

 

You've also said things like "Even Lorentz can not transform the earth into a severely oblate spheroid." so I really can't tell what your position is. But physics is not based on realism. It is based on the premise of measurements being reality. Which you obviously reject.

 

What contradiction?

 

The one we were discussing? About how you can't be both at rest and moving with respect to the preferred frame, so one doesn't exist?

 

You deny realism and contend that reality, including Earth's shape, depends on the frame of reference from which it is seen. This proves that your science is based on idealism in denial that cosmos exists and has properties independent of observation and measurement. (X well over a hundred on that philosophical point.)

 

Yes, I deny realism. But, as I have pointed out before, the choice between realism and idealism is a false dichotomy.

 

 

"Identical physical processes?" Clocks slow down. "Time" is not a process that slows down. Clocks' rates of oscillation vary.

The elapsed time for my dropped ball does not vary, just because two clocks in different frames will have "clocked" the event duration differently. Address that.

 

No, I will not. I gave an scenario and you changed it. I will not defend your straw man.

 

I've explained before that the math is not the explanation of what time dilation means, and that I don't do math. So you go ahead and say... 'see here... the math tells us that time dilates and length contracts.' No, it doesn't.

 

And your assertion here is based on your extensive expertise in physics? No. The math is the explanation of what time dilation means. The description — the words — is figurative.

 

If you agree that "time dilation" simply means that clocks slow down at high speed, etc., then, fine. No explanation of how that works, but... fine. Then you are not allowed the possibility of 'time travel' either if you have repented from the reification of time. Also then we both know that clocks tick as regularly as we can design them to tick and we can compare ticks to other events and say, so much time elapsed, and call it a measurement. But if clocks differ on clocking the same event... they require adjustment... which we've discussed in detail re GPS etc.

 

There is an explanation, but you reject it. In physics there is a dimension of time. It has a nonlinear dependence on speed, so that intervals measured in two frames of reference will disagree. That's what the physics says.

 

Wow! "The actual physics!" No need for mere words to make sense and meaning of it. No need for ontology of time. (See above.) It is what clocks measure!

 

Nope. No need for ontology. Glad you finally agree.

 

You deny realism. Realism states that things are as they are, not depending on your all-important frames of reference from which they are seen and measured.

 

Yes, I deny realism.

 

"...only the observer's frame. Isn't that the essence of realism? "

NO! Just the opposite! How many times have I said that the world doesn't care how we look at it? It is as it is regardless of that. That leaves science the task of always finding the best way to look at whatever is being measured and observed... and, yes, there are better and worse ways to do that.

 

But science is not based on realism. The "best measurement" is one which maximizes precision and minimizes experimental error, which is a completely separate topic.

 

See above reiteration. If we disagree on Earth having a true, intrinsic shape and on the distance (length) to the Sun hanging right around 93 million miles... not getting way shorter (contracted) as seen from... extreme frames... then there is no use for or need of further, more subtle examples.

 

Funny, I want to discuss less subtle examples — ones where actual experiments have been conducted.

 

If I have a physical object that likes to emit and absorb a particular color of light, let's say green. So when it emits light, it emits green light, and if I shine green light on it, it will absorb that light.

 

Now, let's say that object is moving toward me. The light I detect is blue. Or do I just think that it's blue? Is it really green? If I want to shine light on it and have it be absorbed, what light do I shine on it? If the object's "inherent color" is green, should I shine green light on it? What does realism say?

Posted

And I have presented you with evidence of length contraction. You have not rebutted it, because you are not qualified to evaluate it, by your own admission.[/Quote]

 

You have said that atomic nuclei in an accelerator appear flattened. I have no expertise with which to evaluate that. You insist that the same principle applies to a flattened appearing Earth. I am aware of plenty of evidence that Earth does not become flattened in any circumstance, even though it might appear so if we flew by it fast enough. I have said that there is no evidence of transference from the micro scale of high speed nuclei to the macro scale observing Earth from a high speed frame.

 

You've also said things like "Even Lorentz can not transform the earth into a severely oblate spheroid." so I really can't tell what your position is. But physics is not based on realism. It is based on the premise of measurements being reality. Which you obviously reject.

My position contrasts appearances with the natural, intrinsic shapes involved.

Do you understand philosophy of science well enough to realize that the world/cosmos does not depend on our measurements for its reality? I think not.... "measurements being reality."

Can you even imagine the cosmos existing with no one around to measure it? Would there be no cosmos without us here to measure it and verify its existence and describe its properties from all these various perspectives? Would Earth have no shape without we variously measure it? Surely you can see how ridiculous this form of idealism is... like what you see ceases to exist every time you blink, not observing it.

 

The one we were discussing? About how you can't be both at rest and moving with respect to the preferred frame, so one doesn't exist?

 

You said, " We are not at rest with respect to it, but we are not moving with respect to it.”

That is clearly nonsense, but now you admit that one can not be both at rest and moving with respect to the same frame.... "so one doesn't exist" is more nonsense.

 

Yes, I deny realism. But, as I have pointed out before, the choice between realism and idealism is a false dichotomy.

 

Again, realism says that the world exists as is independent of observation and measurement. You say that physics "is based on the premise of measurements being reality." ... No reality, no world without our measurements. We create the cosmos by observing it, and it has no reality apart from our observing it. All astute philosophers of science, hearing this will be laughing their asses off.

 

And your assertion here is based on your extensive expertise in physics? No. The math is the explanation of what time dilation means. The description — the words — is figurative.

 

My expertise is derived from a longtime interest in and study of the ontology of time. See thread title.

Do you still think that time travel is possible or not? You said you do, so you reify it. You think "it" changes (slows down) and makes clocks slow down, so you reify it.

 

There is an explanation, but you reject it. In physics there is a dimension of time. It has a nonlinear dependence on speed, so that intervals measured in two frames of reference will disagree. That's what the physics says.

 

How is time a "dimension?" Things move and we say time elapses as they do. The Sun is 8 light minutes away. That is a measure of its distance from Earth. So it takes sunlight 8 minutes to reach Earth. How is that elapsed time a "dimension?" That is what ontology demands of physics.

 

me:

Wow! "The actual physics!" No need for mere words to make sense and meaning of it. No need for ontology of time. (See above.) It is what clocks measure!

You:

Nope. No need for ontology. Glad you finally agree.

Cute! Tit for tat with the sarcasm. But seriously... answer my time questions/challenges above.

 

Yes, I deny realism.

Good for you!... A scientist who doesn't believe the world exists as is on its own or has properties of its own independent of measurements, which bestow reality upon the world.

Funny, I want to discuss less subtle examples — ones where actual experiments have been conducted.

 

If I have a physical object that likes to emit and absorb a particular color of light, let's say green. So when it emits light, it emits green light, and if I shine green light on it, it will absorb that light.

 

Now, let's say that object is moving toward me. The light I detect is blue. Or do I just think that it's blue? Is it really green? If I want to shine light on it and have it be absorbed, what light do I shine on it? If the object's "inherent color" is green, should I shine green light on it? What does realism say?

 

Well I am not an expert in spectronomy (whatever... with a spectrometer), but if you could set aside your belief that the world is as you see it for a moment...

A spectrometer at rest with the object will show what wavelength it is emitting, regardless of how the lightwaves are compressed or stretched from your perspective from frames not at rest with the object.

That would be realism.

Posted

You have said that atomic nuclei in an accelerator appear flattened. I have no expertise with which to evaluate that. You insist that the same principle applies to a flattened appearing Earth. I am aware of plenty of evidence that Earth does not become flattened in any circumstance, even though it might appear so if we flew by it fast enough. I have said that there is no evidence of transference from the micro scale of high speed nuclei to the macro scale observing Earth from a high speed frame.

(emphasis added)

 

No, you have evidence of the earth not being flattened in ONE reference frame.

 

 

My position contrasts appearances with the natural, intrinsic shapes involved.

Do you understand philosophy of science well enough to realize that the world/cosmos does not depend on our measurements for its reality? I think not....

 

I most decidedly did not claim that the cosmos required our measurements to exist; that's just another little straw man on your part. I said what we measure is reality (not measurement creates reality). That is, if I have a properly working device, what I measure is real. So if my light meter tells me I have a blue photon, I have a blue photon. I don't have a green photon that's fooling me somehow, because it was emitted from a moving source, and it's just an illusion. The photon really is blue.

 

"measurements being reality."

Can you even imagine the cosmos existing with no one around to measure it? Would there be no cosmos without us here to measure it and verify its existence and describe its properties from all these various perspectives? Would Earth have no shape without we variously measure it? Surely you can see how ridiculous this form of idealism is... like what you see ceases to exist every time you blink, not observing it.

 

Yes, straw man arguments are often ridiculous. It's called appeal to ridicule, which is a logical fallacy and as such a deprecated argument style.

 

You said, " We are not at rest with respect to it, but we are not moving with respect to it.”

That is clearly nonsense, but now you admit that one can not be both at rest and moving with respect to the same frame.... "so one doesn't exist" is more nonsense.

Admit? I've insisted on it. But how is it nonsense? It's proof by contradiction: I assume this special frame of reference exists. I measure my speed with respect to it. One set of measurements show that I cannot be at rest with respect to it, but another set shows that I am not moving with respect to it. So I have a contradiction. Thus I conclude that this special frame of reference does not exist. How, specifically, is that nonsense?

 

Again, realism says that the world exists as is independent of observation and measurement. You say that physics "is based on the premise of measurements being reality." ... No reality, no world without our measurements. We create the cosmos by observing it, and it has no reality apart from our observing it. All astute philosophers of science, hearing this will be laughing their asses off.

 

Again, (or, rather, still) a straw man.

 

My expertise is derived from a longtime interest in and study of the ontology of time. See thread title.

Do you still think that time travel is possible or not? You said you do, so you reify it. You think "it" changes (slows down) and makes clocks slow down, so you reify it.

 

A longtime interest in and study of the ontology of time gives you no physics chops. Show me the reification from the actual physics in its native language — the equation. Not the convenient misinterpretation of the descriptive language.

 

How is time a "dimension?" Things move and we say time elapses as they do. The Sun is 8 light minutes away. That is a measure of its distance from Earth. So it takes sunlight 8 minutes to reach Earth. How is that elapsed time a "dimension?" That is what ontology demands of physics.

 

I didn't say elapsed time was a dimension.

 

Let's say you are crossing the street. The road has a set of spatial coordinates: x, y and z, which specify where you are. There is a truck, barreling down the street at high speed. It will have those same spatial coordinates at some point on its travel. Does it hit you? You have the same spatial coordinates.

 

Well I am not an expert in spectronomy (whatever... with a spectrometer), but if you could set aside your belief that the world is as you see it for a moment...

A spectrometer at rest with the object will show what wavelength it is emitting, regardless of how the lightwaves are compressed or stretched from your perspective from frames not at rest with the object.

That would be realism.

 

I actually believe we're getting somewhere. You appear to agree that the wave can be changed by the motion, so even though the object emits a green photon, in the other frame this photon will actually be blue, even using this same spectrometer. What this means is that if I want to shoot a photon at the object and have it be absorbed, I have to shoot a red photon at it, because in the object's frame, that photon will be green.

 

Physics recognizes that there is no frame of absolute rest, aka a preferred frame. There is no physics test to show that you are at rest and something else is moving rather than the other way around — you have even recognized this by discussing the rest frame of the earth, despite the fact that the earth is in constant motion about the sun, and the entire solar system is in motion. But motion is always relative to something else. So from the perspective of physics models, i.e. the equations, all frames of reference are equally valid.

 

The only information we can gather about systems is from measurement, so we assume that what we measure is real. There is no cosmic deception going on. Physics is interested in models of how nature behaves. So, in the above example, the model tells me to shoot a red photon at the object, and it works. That model is useful. We keep it. Now, when asked what color light is involved, I can give an equally valid answer from any frame of reference. In my frame, the light really is red. In the object's frame, the light really is green. Both answers are true.

 

That's because physics is not based on realism. There is no compelling reason, from the perspective of model-building, to say that the properties have to be expressed in the rest frame of the object being studied. The physics works either way. Since physics is not based on realism, any objections to physics based on realism are pointless. Physics won't conform to realism, because physics is not based on realism, and you haven't presented any persuasive reason why physics should be overhauled.

Posted (edited)

Swansont;

I'll get back to some of your specific points as time permits, but first, right off the top, concerning:

 

You appear to agree that the wave can

be changed by the motion, so even though the object emits a green photon, in the

other frame this photon will actually be blue, even using this same spectrometer.

 

No. The wave does not change lengths. Realism. The appearence of the wavelength (color of the light) changes with relative movement toward (compacted, blue shift) or away from (stretched, red shifted) the observer’s frame. It “will actually” appear (not “be”) blue because of blue shift due to apparent wave compacting relative to the observer.

 

You have correctly adjusted for the difference by shooting the right color photon to be absorbed by the object, which has an intrinsic color (from spectrometry at rest with, i.e., not moving relative to) different than the shifted color you see.

 

As for the larger picture... why all that matters, referencing your :

 

The physics works either way. Since

physics is not based on realism, any objections to physics based on realism are

pointless. Physics won't conform to realism, because physics is not based on

realism, and you haven't presented any persuasive reason why physics should be overhauled.

 

As my grandchildren begin to study science seriously, I want them to know that Earth has a very well measured and defined shape and distance from the Sun... that the cosmos and all of its parts exist as they are, objectively, with intrinsic properties which science seeks to know as accurately as possible.

They should not be “learning” that Earth’s shape and distance from the Sun depend on how we look at it. (idealism.) You can believe that if you think that length contraction actually makes physical bodies either change shape or have un-knowable shapes or that the distance to the Sun varies because of the “all frames equal” dictum.

 

And when they ask how gravity works, I hope they are taught that we don’t know yet... unless and until we do know. Inventing words without meaning, like “spacetime” does not help our understanding of how gravity works. It is just a visual aid, an imaginary scaffolding for the math, which has improved its use as a tool for prediction.

Same with all the varieties of geometric models which lead to different cosmologies. Ontology always seeks to know how these models actually apply to the “real world” even if non-Euclidean models don’t care anymore whether or not they describe the “real world”... or whether there is one, for that matter.

Anyway, I hope you get my drift. That’s where philosophy of science, epistemology, ontology, and all that "bullshit” (Feynman) comes in.

 

(emphasis added)

 

No, you have evidence of the earth not being flattened in ONE reference frame.

 

No, all the actual evidence is in favor of a nearly spherical Earth. There is no evidence at all for a flattened Earth. Even if we were able to fly by at near ‘c’ and the Earth *appeared* flattened, it would remain spherical, and the Lorentz transformation would be required to “correct the image.”

 

So I have a contradiction. Thus I conclude that this special frame of reference does not exist. How, specifically, is that nonsense?

 

How far back to go in review?....

I have often agreed that everything is moving on all scales.

But if we are talking about a certain colored object and ask, what color is it?, it behooves us to focus on who is asking from what perspective relative to the object. My last post installment covered that in detail. We are not interested in the object’s movement relative to galactic center or relative to the rate of cosmic expansion between galaxies.

 

So, if the object is moving toward you, the color will appear blue shifted, etc. The at rest frame with the object is not moving relative to the object, and that is the frame from which the color of the object, as it is, can be determined by the spectrometer.

Edited by owl
Posted

Philosophy is relevant to Science.

 

Philosophy contributes to the morals we control regardless of the scientific effects of chemical.

 

Philosophy contributes to the meaning of the discoveries made by scientists.

instance, the speed of light cannot be traced. Everything that is used to gage it is a resistor which, if being used to study the light cannot have a determined resistance to annul in the results.

Though true, that is considered philosophical.

 

Philosophy also contributes to un-determinable origin of all things, Because if you are religious, you know Heaven is beyond comprehension.

 

 

Philosophy is relevant to science, because it contributes the debates, which is what furthers research and determines its values.

Posted

No. The wave does not change lengths. Realism. The appearence of the wavelength (color of the light) changes with relative movement toward (compacted, blue shift) or away from (stretched, red shifted) the observer’s frame. It “will actually” appear (not “be”) blue because of blue shift due to apparent wave compacting relative to the observer.

 

How do I tell the difference between a green photon "pretending" to be blue, and an actual blue photon? My meter simply measures the energy/wavelength/frequency, and can't make the distinction you draw.

 

You have correctly adjusted for the difference by shooting the right color photon to be absorbed by the object, which has an intrinsic color (from spectrometry at rest with, i.e., not moving relative to) different than the shifted color you see.

 

How can the object absorb a red photon if it only "appears" green in its frame? Can the object tell the difference somehow?

 

As my grandchildren begin to study science seriously, I want them to know that Earth has a very well measured and defined shape and distance from the Sun... that the cosmos and all of its parts exist as they are, objectively, with intrinsic properties which science seeks to know as accurately as possible.

They should not be “learning” that Earth’s shape and distance from the Sun depend on how we look at it. (idealism.) You can believe that if you think that length contraction actually makes physical bodies either change shape or have un-knowable shapes or that the distance to the Sun varies because of the “all frames equal” dictum.

 

You have to choose between teaching them realism and teaching them science. Science is not based on realism.

 

And when they ask how gravity works, I hope they are taught that we don’t know yet... unless and until we do know.

 

But "how it works" is not the primary goal of science. You can always ask for one more layer of explanation, and eventually you reach "nobody knows". But that's not the same as saying we know nothing about gravity, nor does it mean that the model we have is wrong.

 

Inventing words without meaning, like “spacetime” does not help our understanding of how gravity works. It is just a visual aid, an imaginary scaffolding for the math, which has improved its use as a tool for prediction.

Same with all the varieties of geometric models which lead to different cosmologies. Ontology always seeks to know how these models actually apply to the “real world” even if non-Euclidean models don’t care anymore whether or not they describe the “real world”... or whether there is one, for that matter.

Anyway, I hope you get my drift. That’s where philosophy of science, epistemology, ontology, and all that "bullshit” (Feynman) comes in.

 

Even if you find the answer, there will always be another layer. Meanwhile, there is knowledge in knowing how nature behaves, which is what science does.

 

No, all the actual evidence is in favor of a nearly spherical Earth. There is no evidence at all for a flattened Earth. Even if we were able to fly by at near ‘c’ and the Earth *appeared* flattened, it would remain spherical, and the Lorentz transformation would be required to “correct the image.”

 

All of the actual data is from one frame of reference. Do you, or do you not agree that there is no data from a "near-c flyby" frame of reference? "Even if we were able" certainly implies that you agree. If there is no data, there is no evidence. It is not a rebuttal of my statement. If there are data, please provide them.

 

Or are you trying to turn this into a Zen thing, with some kind of "All of the zero data supports me" koan?

 

How far back to go in review?....

I have often agreed that everything is moving on all scales.

But if we are talking about a certain colored object and ask, what color is it?, it behooves us to focus on who is asking from what perspective relative to the object. My last post installment covered that in detail. We are not interested in the object’s movement relative to galactic center or relative to the rate of cosmic expansion between galaxies.

 

Why does it behoove us to focus on this? From the standpoint of doing science, that is.

 

So, if the object is moving toward you, the color will appear blue shifted, etc. The at rest frame with the object is not moving relative to the object, and that is the frame from which the color of the object, as it is, can be determined by the spectrometer.

 

I will refer you my previous question of how we distinguish between a photon that is blue and one that has been shifted to "appear" that color.

Posted (edited)

How do I tell the difference between a green photon "pretending" to be blue, and an actual blue photon? My meter simply measures the energy/wavelength/frequency, and can't make the distinction you draw.[/Quote]

 

I thought I already answered that in these two pieces:

 

No. The wave does not change lengths. Realism. The appearance of the wavelength (color of the light) changes with relative movement toward (compacted, blue shift) or away from (stretched, red shifted) the observer’s frame. It “will actually” appear (not “be”) blue because of blue shift due to apparent wave compacting relative to the observer.

 

You have correctly adjusted for the difference by shooting the right color photon to be absorbed by the object, which has an intrinsic color (from spectrometry at rest with, i.e., not moving relative to) different than the shifted color you see.

The answer is emphasized above. Movement of the object relative to the observer causes the apparent shift. At rest with the object tells you what color it is emitting (or reflecting.) The difference is the "shift."

 

How can the object absorb a red photon if it only "appears" green in its frame? Can the object tell the difference somehow?

 

You corrected for the shift, so you gave it what it can absorb, having known the shifted difference.

 

You have to choose between teaching them realism and teaching them science. Science is not based on realism.

With what part of this do you disagree (or all of it?):

 

They should not be “learning” that Earth’s shape and distance from the Sun depend on how we look at it. (idealism.) You can believe that if you think that length contraction actually makes physical bodies either change shape or have un-knowable shapes or that the distance to the Sun varies because of the “all frames equal” dictum.

 

You:

But "how it works" is not the primary goal of science. You can always ask for one more layer of explanation, and eventually you reach "nobody knows". But that's not the same as saying we know nothing about gravity, nor does it mean that the model we have is wrong.

 

Given a choice between GR’s curved spacetime and Quantum Theory’s gravitons, how do you know which is is right, if either, given that both spacetime and gravitons are words without real world referents, i.e., meaningless metaphysical concepts?

 

Even if you find the answer, there will always be another layer. Meanwhile, there is knowledge in knowing how nature behaves, which is what science does.

 

Planets "behave" by orbiting around the Sun. Do you have any interest, as a scientist, in how that force of attraction is conveyed? I do, but nobody knows... yet.

Is... “ mass curves space and curved space guides them”... a legitimate answer in your mind, even though the ontology of spacetime is far from settled?

 

All of the actual data is from one frame of reference. Do you, or do you not agree that there is no data from a "near-c flyby" frame of reference? "Even if we were able" certainly implies that you agree. If there is no data, there is no evidence. It is not a rebuttal of my statement. If there are data, please provide them.

 

Yes, that has always been my point. There is no data, no evidence for an actually flattened Earth, even though it may appear flattened from that very fast moving frame.

Again, there is no evidence for a flattened Earth, so teaching that its actual shape (yes, it has an actual, intrinsic shape of its own!) depends on frame of reference, including flattened if seen as above, is wrong. You've still got it backwards. If there are data that a flattened Earth is an equally valid description (and there aren't... grammar edit)... "please provide them."

 

Or are you trying to turn this into a Zen thing, with some kind of "All of the zero data supports me" koan?

 

No. It's very simple, as bolded above.

Why does it behoove us to focus on this? From the standpoint of doing science, that is.

 

Your example was about the color of an object. We both know about apparent shift of wavelength (and color) with movement of the object either toward or away from the observer. To find out what color the object itself is actually emitting, we must "control for" that movement. That means, in this case, to "look at it" from at rest with it... not moving relative to the object. There is nothing about that which is difficult to understand... yet you manage.

 

I will refer you my previous question of how we distinguish between a photon that is blue and one that has been shifted to "appear" that color.

 

By measuring wavelength from at rest with the object, eliminating the movement which causes the apparent shift. Basic experimental/observational design.

Edited by owl
Posted

I thought I already answered that in these two pieces:

 

No, you answered some other question.

 

The answer is emphasized above. Movement of the object relative to the observer causes the apparent shift. At rest with the object tells you what color it is emitting (or reflecting.) The difference is the "shift."

 

The use of "apparent" is what is causing trouble here. What is this "apparent" shift? Saying that the shift is "apparent" (as opposed to real) implies that there is some difference. If I detect a blue photon, is there a way of telling whether it is a blue photon from my reference frame or a green photon that has been blue-shifted?

 

You corrected for the shift, so you gave it what it can absorb, having known the shifted difference.

 

But that means the shift is real. Not apparent. The object only absorbs green, so it would seem that the shift was not merely "apparent".

 

With what part of this do you disagree (or all of it?):

 

You cannot teach realism and science simultaneously. They disagree, as science is not based on realism. Or idealism, for that matter.

 

Given a choice between GR’s curved spacetime and Quantum Theory’s gravitons, how do you know which is is right, if either, given that both spacetime and gravitons are words without real world referents, i.e., meaningless metaphysical concepts?

 

There is no confirmed quantum theory of gravitation. But, that aside, it will have to agree with GR in the realm where GR applies. You decide which is "right" ("right" is never an absolute, it is always the best explanation we have) by whatever is in best agreement with observation.

 

Planets "behave" by orbiting around the Sun. Do you have any interest, as a scientist, in how that force of attraction is conveyed? I do, but nobody knows... yet.

 

I do, too, but no knowing does not prevent us from sending spacecraft to orbit the earth or other bodies or from figuring out how tides work, etc. There's still a whole bunch of science that's been done over the years without having answered that question.

 

Is... “ mass curves space and curved space guides them”... a legitimate answer in your mind, even though the ontology of spacetime is far from settled?

 

Yes.

 

When all we had was Newtonian gravity, there was no mechanism there, either. Is "mass has some property such that it attracts mass and F=ma" somehow an acceptable answer, but "mass curves space and curved space guides them" is not?

 

Yes, that has always been my point. There is no data, no evidence for an actually flattened Earth, even though it may appear flattened from that very fast moving frame.

 

And you cannot make a claim without data. You can make a prediction, however. But the issue again is with "appear flattened". What does that mean? How do my instruments tell the difference between a signal that has certain properties and one that simply "appears" to have some properties?

 

Again, there is no evidence for a flattened Earth, so teaching that its actual shape (yes, it has an actual, intrinsic shape of its own!) depends on frame of reference, including flattened if seen as above, is wrong. You've still got it backwards. If there are data that a flattened Earth is an equally valid description (and there aren't... grammar edit)... "please provide them."

 

There are data that a flattened nucleus in a moving frame is an equally valid description, and that should be enough to reject realism. In a broader sense, the Lorentz symmetry of physics means that all of the equations will be equally valid in all reference frames. Again, that rejects realism.

 

And this is where wording like "actual intrinsic shape" causes problems. If I do my high-speed approach and get my readings, ""actual intrinsic shape" sounds like you want me to ignore the flattened shape I detect and use a sphere in my calculation (though how I should know that it's a sphere is another question), even though using a sphere gives me the wrong answer.

 

Then you agree that the flattened shape is a Lorentz transform of a sphere, so I can take the flattened shape, Lorentz transform it into a sphere to use the "correct" shape, then Lorentz transform the sphere back into the flattened shape so that I can use my physics equations to solve whatever problem I want to solve. That seems to be a pretty silly and useless exercise, which is one reason that science rejects realism. The Lorentz symmetry of physics means that I can solve the problem in my frame and get the answer I need. Occam's razor demands that science reject realism.

 

But there's an additional practical issue. What if I don't know the details about the source of a signal I am getting? I observe a particular shape, but don't know how fast the object is moving with respect to me — my data are limited. So I could not determine an "intrinsic shape" for it, but that does not prevent me from solving the physics problem. Same thing with detecting light — I detect a blue photon but do not know its source. A demand of realism places extra burdens on science. It has no practical value. Rejected.

 

No. It's very simple, as bolded above.

 

 

Your example was about the color of an object. We both know about apparent shift of wavelength (and color) with movement of the object either toward or away from the observer. To find out what color the object itself is actually emitting, we must "control for" that movement. That means, in this case, to "look at it" from at rest with it... not moving relative to the object. There is nothing about that which is difficult to understand... yet you manage.

 

By measuring wavelength from at rest with the object, eliminating the movement which causes the apparent shift. Basic experimental/observational design.

 

I'l give you a chance to explain the difference between an "apparent" and real shift in frequency. If I detect a blue photon, and that's all the information I have, how can I know whether it is "really blue" or it has been shifted to be "apparently blue"?

Posted

Swansont:

The only information we can gather about systems is from measurement, so we assume that what we measure is real.

We have an abundance of ways to know (ref: epistemology) the actual distance to the Sun. The better our instruments and techniques get, the more precise and exact the measurements. Same with size and shape of Earth.

 

So, along comes our favorite length contraction based thought experiment... the near ‘c’ fly by guy... and he measures the distance to the Sun to be, oh, say ten or fifteen million miles.

How “real” is that? Should we teach our children that the distance to the Sun is somewhere between 10 and 93 million miles, depending on how we measure it, and assume that all frames of reference yield equally accurate results?

 

This is not science. It is a contemporary version of idealism which claims that reality is however we see it, from whatever extreme velocity.

 

You can dance around this argument all you want and claim that apparently squeezed nuclei in an accelerator makes an apparently squeezed Earth or shortened distance to the Sun just as real as the well known facts.

 

That also means that all well known astronomical distances between cosmic objects are not well known at all, because they drastically change with whatever our velocity is relative to them. This is bs at its worst, and it does in fact deny that the world is real all by itself, and asserts that our observations/measurements, as variable as they are, determine “reality.”

 

This is a philosophical perspective repeated quite often against the philosophy that there is no intrinsic cosmos with its own reality, but rather that reality is defined by how we measure it. The at rest frame is the way to observe and measure whatever part of that cosmos, because very high speed apparently distorts “appearances.” Probably quite obvious to everyone but length contraction fanatics.

 

No, you answered some other question.[/Quote]

 

"Some other question?" What other question? Are you trying to be evasive by intentionally avoiding being specific? It only adds to piss poor communication here, like clarity might be an embarrassment to your argument.

 

The use of "apparent" is what is causing trouble here. What is this "apparent" shift? Saying that the shift is "apparent" (as opposed to real) implies that there is some difference. If I detect a blue photon, is there a way of telling whether it is a blue photon from my reference frame or a green photon that has been blue-shifted?

 

What appears to the eye of the observer here (wavelength/color of light) has been compacted by movement after it was emitted as its original wavelength/color.

 

..."is there a way of telling...?" Yes, and I've already "told" quite a few times. The apparent shift is due to movement, so to see it as it is emitted means we must see it from at rest to eliminate the reason for the shift and get back to the intrinsic color emitted by the object. Would it help if i repeated that a few more times?

But that means the shift is real. Not apparent. The object only absorbs green, so it would seem that the shift was not merely "apparent".

 

You seem very confused to me. What part of my above reiterated explanation did you not understand? Yes, you could say that that the shift is real. The observer sees the color differently than the object itself is emitting, and the difference is a shift due to movement... blah, blah, blah.

 

You cannot teach realism and science simultaneously. They disagree, as science is not based on realism. Or idealism, for that matter.

 

You deny that that the world is real independent of measurement. That is not science. Science accepts that the world is real ('all by itself') and devises the best ways to observe and measure it to accurately describe that reality.

If, like you, they say Earth appears flattened (from the usual extreme frame), and appearance/measurement determines reality, therefore Earth is flattened... not just appears flattened... from that frame of reference... then frame of reference determines reality. This claims that there is no reality besides appearances and their measurements. If you are not philosopher enough to see how bogus this is, I am ready to quit with you.

 

I'm tired of explaining that measurements can distort reality, especially in my favorite and often repeated instances.

 

No, swansont, Earth is not flattened and will never be flattened, even if we ever get to see it from that super fast fly by frame. It will stay nearly spherical and you and your lenght contraction fanatic colleagues will stay wrong about its "true shape." Yes, it has a true shape which doesn't depend on how we look at it. But up close and at rest with it will always be the best way to look at it for an accurate description.

 

I may or may not finish the point by point reply to your post. It's obviously useless.

One more:

 

I'l give you a chance to explain the difference between an "apparent" and real shift in frequency. If I detect a blue photon, and that's all the information I have, how can I know whether it is "really blue" or it has been shifted to be "apparently blue"?

 

You can not know unless you know its velocity relative to you. But that does not mean that it has no actual color/wavelength until you get that info. Of course it will be very clear from the at rest frame, if you could get close or at least not be moving relative to it.

Posted

Swansont:

 

We have an abundance of ways to know (ref: epistemology) the actual distance to the Sun. The better our instruments and techniques get, the more precise and exact the measurements. Same with size and shape of Earth.

 

And that is a measurement. That measurement is valid for that frame.

 

So, along comes our favorite length contraction based thought experiment... the near ‘c’ fly by guy... and he measures the distance to the Sun to be, oh, say ten or fifteen million miles.

How “real” is that? Should we teach our children that the distance to the Sun is somewhere between 10 and 93 million miles, depending on how we measure it, and assume that all frames of reference yield equally accurate results?

 

Yes, we should.

 

This is not science. It is a contemporary version of idealism which claims that reality is however we see it, from whatever extreme velocity.

 

It is science, and someone who has taught about the philosophy of science should know this. Science is not based on realism.

 

You can dance around this argument all you want and claim that apparently squeezed nuclei in an accelerator makes an apparently squeezed Earth or shortened distance to the Sun just as real as the well known facts.

 

Again, you need to define what you mean by "apparently". From some of what you have written, it would seem you agree that it is what our instruments would measure.

 

If I want to calculate the answer to some physics problem, I can do all of the calculations from my own frame of reference and get the right answer. There no reason to apply realism and do the calculation in the rest frame. Indeed, in problems such as collisions, there is no single rest frame. How does realism deal with collision problems? In physics, the center-of mass frame is often the easiest one to use.

 

That also means that all well known astronomical distances between cosmic objects are not well known at all, because they drastically change with whatever our velocity is relative to them. This is bs at its worst, and it does in fact deny that the world is real all by itself, and asserts that our observations/measurements, as variable as they are, determine “reality.”

 

This is a philosophical perspective repeated quite often against the philosophy that there is no intrinsic cosmos with its own reality, but rather that reality is defined by how we measure it. The at rest frame is the way to observe and measure whatever part of that cosmos, because very high speed apparently distorts “appearances.” Probably quite obvious to everyone but length contraction fanatics.

 

If you want to go measure the attributes of the planets, distant stars or the black hole at the center of the galaxy, go ahead and do it. But it seems to me that we are stuck pretty close to earth, and that we have to make measurements from our frame of reference. Are our measurements invalid because we are not in the rest frame of the objects we are observing?

 

As with my previous example, it is a useless exercise to get information, transform it to the rest frame to get the so-called "real" information, and then transform it back, meaning you can ignore all that because you want to do the calculations in your own frame of reference. If I want to do a particle physics experiment and I find it useful to use the rest frame of the particle, then I had damned well better account for length contraction if I want the experiment to work.

 

If I choose a philosophy that dictates a particular frame of reference, then what happens is that the physics I use is now dependent on my frame of reference. In other words, I have an infinite set of laws of physics, each one being like an epicycle within an epicycle, mandated because someone demanded that the earth be the center of the universe and all orbits be circles. It can be made to work in some instances (and you're missing out, because the math involved is quite interesting), but it's cumbersome and is discarded because there is a simpler solution at hand.

 

"Some other question?" What other question? Are you trying to be evasive by intentionally avoiding being specific? It only adds to piss poor communication here, like clarity might be an embarrassment to your argument.

 

I have no idea what question you thought you were answering, nor could I possibly know what question you thought you were answering. So I don;t see how I am to blame. What I do know is that you did not provide an answer to the question I asked.

 

What appears to the eye of the observer here (wavelength/color of light) has been compacted by movement after it was emitted as its original wavelength/color.

 

..."is there a way of telling...?" Yes, and I've already "told" quite a few times. The apparent shift is due to movement, so to see it as it is emitted means we must see it from at rest to eliminate the reason for the shift and get back to the intrinsic color emitted by the object. Would it help if i repeated that a few more times?

 

No, repeating will not help. Clarifying will.

 

You seem very confused to me. What part of my above reiterated explanation did you not understand? Yes, you could say that that the shift is real. The observer sees the color differently than the object itself is emitting, and the difference is a shift due to movement... blah, blah, blah.

 

Yes, I am confused, because you have been using "apparent" and "real" interchangeably, and they don't mean the same thing.

 

You deny that that the world is real independent of measurement. That is not science. Science accepts that the world is real ('all by itself') and devises the best ways to observe and measure it to accurately describe that reality.

 

No, I have not denied that. In fact I specifically pointed out science's position on this just yesterday.

 

If, like you, they say Earth appears flattened (from the usual extreme frame), and appearance/measurement determines reality, therefore Earth is flattened... not just appears flattened... from that frame of reference... then frame of reference determines reality. This claims that there is no reality besides appearances and their measurements. If you are not philosopher enough to see how bogus this is, I am ready to quit with you.

 

If measurement does not determine what reality is, what does? What avenue do we have to determine reality, other than measurement?

 

I'm tired of explaining that measurements can distort reality, especially in my favorite and often repeated instances.

 

Measurements can distort reality? Remind me of what you are talking about here.

 

No, swansont, Earth is not flattened and will never be flattened, even if we ever get to see it from that super fast fly by frame. It will stay nearly spherical and you and your lenght contraction fanatic colleagues will stay wrong about its "true shape." Yes, it has a true shape which doesn't depend on how we look at it. But up close and at rest with it will always be the best way to look at it for an accurate description.

 

I may or may not finish the point by point reply to your post. It's obviously useless.

 

"Accurate description" implies, once again, that this is a measurement error issue, and yet you have previously acknowledged that it is not. This seems inconsistent.

 

You can not know unless you know its velocity relative to you. But that does not mean that it has no actual color/wavelength until you get that info. Of course it will be very clear from the at rest frame, if you could get close or at least not be moving relative to it.

 

Well, if you have to have this additional information, then it makes doing science harder. Which is a reason to discard the philosophy. Scientists do not generally control the kind of information they are able to get in an experiment.

Posted (edited)

And that is a measurement. That measurement is valid for that frame.

(Ref; my):

We have an abundance of ways to know (ref: epistemology) the actual distance to the Sun. The better our instruments and techniques get, the more precise and exact the measurements. Same with size and shape of Earth.

It is also the accurate "realistic" info on the Au and Earth science. Earth is not, in fact, flattened, nor is the real/actual distance to the Sun 10 million miles.

 

me:

Should we teach our children that the distance to the Sun is somewhere between 10 and 93 million miles, depending on how we measure it, and assume that all frames of reference yield equally accurate results?

 

Yes, we should.

 

I'm glad you are not their astronomy teacher!

It might sound something like this:

"In my class you will learn that there is no real cosmos independent of our measurements, so all astronomy and Earth science taught here will depend on how we look at it, i.e., from all varieties of frames of reference, yielding a vast variety of answers to all your questions about Earth's size and shape and the distances between bodies in our solar system.

I repeat, reality depends on our measurements, which vary drastically with frames of reference."

No, thanks. Not science.

 

It is science, and someone who has taught about the philosophy of science should know this. Science is not based on realism.

 

No, it's not science. Earth's shape does not depend on how you look at it. To claim that it does is idealism. Study some philosophy before you teach the kind of crap in the hypothetical situation 'quoted' above.

Again, you need to define what you mean by "apparently". From some of what you have written, it would seem you agree that it is what our instruments would measure.

 

I 'defined' "apparently" in detail with your colored object. The color the object is emitting is its actual color. The color you see is distorted by compacting waves due to its movement toward you. This distortion from what it is emitting to what you see is the well known shifted effect... shifted from what it is emitting to how you see it, how it appears to you. That is as clear as I can make the distinction.

 

If I want to calculate the answer to some physics problem, I can do all of the calculations from my own frame of reference and get the right answer. There no reason to apply realism and do the calculation in the rest frame. Indeed, in problems such as collisions, there is no single rest frame. How does realism deal with collision problems? In physics, the center-of mass frame is often the easiest one to use.

 

My argument is not with your use of calculations. It is with your philosophical assumption that measurement determines reality, that the actual shape of earth IS flattened when/if you measure it to be so. What it's shape IS is different than what its shape might APPEAR TO BE from an extreme frame.

That applies also to your galactic scale example:

If you want to go measure the attributes of the planets, distant stars or the black hole at the center of the galaxy, go ahead and do it.

... (etc.)

 

The point is they have actual, real, intrinsic "attributes," so when we see squished spheres and ridiculously short distances between bodies, we must have enough sense to 'translate' appearances into accurate descriptions.

 

I have no idea what question you thought you were answering, nor could I possibly know what question you thought you were answering. So I don;t see how I am to blame. What I do know is that you did not provide an answer to the question I asked.

 

Well, that is all very unclear at this point. If you repeat the question referenced above, at least I would know which one to address in this case. I have asked you so many questions, left un-answered, that I've lost track. "Is time travel possible?" was one you avoided. Does "time slows down" mean something different than "clocks slow down"... is another, the latter being a de-reification of time.

 

No, repeating will not help. Clarifying will.

 

True. I was being sarcastic again. I am doing my best to clarify.

 

Yes, I am confused, because you have been using "apparent" and "real" interchangeably, and they don't mean the same thing.

The "real Earth" is nearly spherical. One possible "apparent Earth" could be squished nearly flat. I've used this example until we all must be tired of hearing it, but still you are "confused" about the above distinction.

 

I hope all of the above has "clarified" that.

Ref; me:

You deny that that the world is real independent of measurement. That is not science. Science accepts that the world is real ('all by itself') and devises the best ways to observe and measure it to accurately describe that reality.

you:

 

No, I have not denied that. In fact I specifically pointed out science's position on this just yesterday.

 

I'll get back to this. (I may lose my post if I chase around reviewing.)

 

If measurement does not determine what reality is, what does? What avenue do we have to determine reality, other than measurement?

...

Measurements can distort reality? Remind me of what you are talking about here.

 

Reality: Everybody knows the shape of Earth, its exact dimensions and all... from, you know... at rest with it, and living on it as we do and applying our best science of observation.

Yes, measurements can distort reality. If you find a way (go very fast past it) to "measure it" as having a 1000 mile equatorial diameter, that measurement would "distort" its reality.

So science must be intelligent enough to observe and measure from the best possible frame of reference (or translate the differences intelligently.) Of course this flies in the face of the dictum that "there are no preferred frames of reference."

"Accurate description" implies, once again, that this is a measurement error issue, and yet you have previously acknowledged that it is not. This seems inconsistent.

Whenever possible, choose an at rest frame, not moving with reference to the object of measurement. When not possible, use the appropriate tools, like the Lorentz transformation, to "translate" from silly flattened bodies to the near-spheres they "actually" are, in "reality." But first you have to get over denial of reality, i.e., realism.

 

Well, if you have to have this additional information, then it makes doing science harder. Which is a reason to discard the philosophy. Scientists do not generally control the kind of information they are able to get in an experiment.

I understand. Use your tools, as just stated. Just don't throw out the knowledge that cosmos does not depend on measurements for its "reality." The latter is realism.

 

To the exchange I postponed above:

me:

I have said that there is no evidence of transference from the micro scale of high speed nuclei to the macro scale observing Earth from a high speed frame
.

You:

No, you have evidence of the earth not being flattened in ONE reference frame.

 

EARTH IS NOT FLATTENED. An extreme frame of observation can not not make it flattened!

me:

My position contrasts appearances with the natural, intrinsic shapes involved.

Do you understand philosophy of science well enough to realize that the world/cosmos does not depend on our measurements for its reality? I think not....

You:

I most decidedly did not claim that the cosmos required our measurements to exist; that's just another little straw man on your part. I said what we measure is reality (not measurement creates reality). That is, if I have a properly working device, what I measure is real.

 

You claim here that a flattened Earth is real if you measure it to be flattened. You also claimed that the distance to the Sun varies between 10 and 93 million miles, because our measurements of that distance can vary that much."What we measure is reality."

Edited by owl
Posted

I'm glad you are not their astronomy teacher!

It might sound something like this:

"In my class you will learn that there is no real cosmos independent of our measurements, so all astronomy and Earth science taught here will depend on how we look at it, i.e., from all varieties of frames of reference, yielding a vast variety of answers to all your questions about Earth's size and shape and the distances between bodies in our solar system.

I repeat, reality depends on our measurements, which vary drastically with frames of reference."

No, thanks. Not science.

 

To say "not science" is disingenuous, because if they were to take a sufficiently advanced science class, they would most certainly learn about relativity. While your disdain is evident, to assert that science is based on realism is folly.

 

No, it's not science. Earth's shape does not depend on how you look at it. To claim that it does is idealism. Study some philosophy before you teach the kind of crap in the hypothetical situation 'quoted' above.

 

"Not science" and "study some philosophy" — pick one. You can't demand both realism and science. They are incompatible. Science is not based on realism.

 

I 'defined' "apparently" in detail with your colored object. The color the object is emitting is its actual color. The color you see is distorted by compacting waves due to its movement toward you. This distortion from what it is emitting to what you see is the well known shifted effect... shifted from what it is emitting to how you see it, how it appears to you. That is as clear as I can make the distinction.

 

Not sufficient detail. You seem to keep hedging. This time you say the color is "distorted" and talk about "how it appears to you".

 

If I measure the wavelength of a photon to be 450 nm (i.e. blue), is there any way — from that measurement — to tell the difference between a photon that was emitted at 450 nm, or one that was emitted at 550 nm (green) and shifted to 450 nm because the source was moving. Any difference in those photons?

 

 

My argument is not with your use of calculations. It is with your philosophical assumption that measurement determines reality, that the actual shape of earth IS flattened when/if you measure it to be so. What it's shape IS is different than what its shape might APPEAR TO BE from an extreme frame.

Reality: Everybody knows the shape of Earth, its exact dimensions and all... from, you know... at rest with it, and living on it as we do and applying our best science of observation.

Yes, measurements can distort reality. If you find a way (go very fast past it) to "measure it" as having a 1000 mile equatorial diameter, that measurement would "distort" its reality.

So science must be intelligent enough to observe and measure from the best possible frame of reference (or translate the differences intelligently.) Of course this flies in the face of the dictum that "there are no preferred frames of reference."

 

If measurements cannot necessarily be trusted, because they can be distorted, how do you know you can trust the measurement made in the rest frame of the object?

 

 

Whenever possible, choose an at rest frame, not moving with reference to the object of measurement. When not possible, use the appropriate tools, like the Lorentz transformation, to "translate" from silly flattened bodies to the near-spheres they "actually" are, in "reality." But first you have to get over denial of reality, i.e., realism.

 

As I have already stated, you have that option of applying the "correction" to the "distortion", but then you would also have to apply an identical correction to the laws of physics, which currently display Lorentz symmetry. Since the correction cancels, why bother? You end up with a more cumbersome construct. Occam says no, don't do it that way.

 

IOW, to adopt realism would mean that the laws of physics would depend on your frame of reference, which isn't very elegant. Pick your poison. Physics chose the elegance of the laws being the same in all frames.

 

I understand. Use your tools, as just stated. Just don't throw out the knowledge that cosmos does not depend on measurements for its "reality." The latter is realism.

 

The "tools" form the basis of physics. They are held as higher than the details we discern. Science rejected realism. If you claim otherwise ("that isn't science") you are in serious denial about the path science chose more than 100 years ago.

Posted (edited)

To say "not science" is disingenuous, because if they were to take a sufficiently advanced science class, they would most certainly learn about relativity. While your disdain is evident, to assert that science is based on realism is folly.[/Quote]

 

To say that I have a disdain for relativity in general is disingenuous. I’ve explained the parts of relativity I criticize many times, yet you persist in misrepresenting my position. That is disingenuous.

Hopefully, as they learn about relativity, they will learn the difference between IS and APPEARS as I have persistently argued. In that process they will learn that the only change in distance between Earth and Sun is due to its elliptical orbit... not a circle with a given (edit from 'diameter') radius. Likewise, its shape is not up for debate.

 

"Not science" and "study some philosophy" — pick one. You can't demand both realism and science. They are incompatible. Science is not based on realism.

 

Science is based on the study of the world as it IS, (“really”.) How it might APPEAR from high speed frames of reference is another question, properly the subject of study for how the appearance of length contraction might apply on macro scale. In any case, the results would not change the shape of Earth, or make that frame's description "equally valid" with its well known shape.

 

Not sufficient detail. You seem to keep hedging. This time you say the color is "distorted" and talk about "how it appears to you".

 

The wavelength of light has different colors in different parts of the spectrum.Surely you know that. As light is emitted (or reflected) from an object, that is the color of the object. How you see it will be different than how it is emitted (intrinsic color of the object) if there is movement between observer and object observed. The difference is between the wavelength (color) it has as emitted and the wavelength (color) you see after it is compressed by movement, thus “distorted” from its emitted/intrinsic color/wavelength. Is that enough detail?

 

I’ll get back to the rest soon.

 

Just an add on here.

Reviewing, I saw this again from ydoaPs (no tag, sorry) which helps clarify my version of “Not Invarient.”

ydoaPs:

"Not invariant" is a very specific kind of varying. If something is "constant", it

doesn't change within a frame of reference. If something is "invariant", it doesn't

change when reference frames are changed.

 

I would apply this to the Earth-Sun distance (length.) "Realistically" it stays the same (is “invariant”) “when reference frames are changed.”... Even when the 'fly-by-guy' sees it differently.

 

This could resolve the debate here.... If the distance to the Sun is not categorized as “length” (a semantics debate) and fit into the “Length is Not Invarient” belief.

So then the Au can be, as it is, a constant... regardless of frame of observation... the ellipse being trivial.

Edited by owl
Posted

To say that I have a disdain for relativity in general is disingenuous. I’ve explained the parts of relativity I criticize many times, yet you persist in misrepresenting my position. That is disingenuous.

 

You misrepresent relativity all too often (and yes, I get to be the judge of that). What you show disdain for is relativity.

 

Hopefully, as they learn about relativity, they will learn the difference between IS and APPEARS as I have persistently argued.

 

Case in point. The position of relativity is that length in not an invariant quantity, time is a nonlinear dimension and that there is no preferred frame. You don't agree with these basic elements of relativity (or you've disguised your agreement well)

 

In that process they will learn that the only change in distance between Earth and Sun is due to its elliptical orbit... not a circle with a given (edit from 'diameter') radius. Likewise, its shape is not up for debate.

 

Not if they want to pass the course.

 

The wavelength of light has different colors in different parts of the spectrum.Surely you know that. As light is emitted (or reflected) from an object, that is the color of the object. How you see it will be different than how it is emitted (intrinsic color of the object) if there is movement between observer and object observed. The difference is between the wavelength (color) it has as emitted and the wavelength (color) you see after it is compressed by movement, thus “distorted” from its emitted/intrinsic color/wavelength. Is that enough detail?

 

No. You didn't get around to answering the question I asked. Is there any difference between the two photons I described?

Posted (edited)

You misrepresent relativity all too often (and yes, I get to be the judge of that). What you show disdain for is relativity.

 

Case in point. The position of relativity is that length in not an invariant quantity, time is a nonlinear dimension and that there is no preferred frame. You don't agree with these basic elements of relativity (or you've disguised your agreement well)[/Quote]

 

If "length is not invariant" means that the shape of Earth and distance to the Sun vary with observation, it is wrong and should not be taught as valid science.

If "time is a nonlinear dimension" means that "it exists" in a way that can slow down (change rates of elapsing) or be "traveled through" it is wrong. (Still no reply to my last "time" challenges.)

And if "there is no preferred frame" means that how we might see things from a near 'c' frame is as valid a description of them as from at rest with them, in the same frame, then that is wrong.

 

Not if they want to pass the course.

 

If they see how all three are wrong, they will pass, (ace the course) even though they disagree with these mainstream relativity misconceptions. Saying, 'relativity says so' doesn't make it right. There is a "real world" out there (realism), whether you believe it or not, and it does not depend on how we see it for its reality. Science's job is to see it as accurately as possible.

 

No. You didn't get around to answering the question I asked. Is there any difference between the two photons I described?

 

Your original example of how you see it vs what color it is:

If I have a physical object that likes to emit and absorb a particular color of light, let's say green. So when it emits light, it emits green light, and if I shine green light on it, it will absorb that light.

 

Now, let's say that object is moving toward me. The light I detect is blue. Or do I just think that it's blue? Is it really green? If I want to shine light on it and have it be absorbed, what light do I shine on it? If the object's "inherent color"

is green, should I shine green light on it? What does realism say?

 

I addressed it in detail already but now it’s about what color is a photon. The original color as emitted changes as movement causes shift. (Yet again)

Then I agreed that you shot the right color of photon to be absorbed by the object, knowing that the wavelength you see had shifted.

me:

... but if you

could set aside your belief that the world is as you see it for a moment...

*

 

Not.

In review, another detail... You said:

 

Physics recognizes that there is no frame of absolute rest, aka a preferred frame.

 

“Absolute?” Of course we are not talking about your object as the one thing in the cosmos not moving. (Absurd.) Is this a change of goal posts on your part? How about relatively at rest, like in the same frame, not moving relative to an object observed. Science would “prefer” that frame to see what color/wavelength the object is “actually” emitting.

 

You go on... “so we assume that what we measure is real.”

 

I addressed the real vs the apparent in your example already.

 

You say:

In my frame, the light really is red. In

the object's frame, the light really is green.... Both answers are true.

 

See * above. “Really?” “In your frame” is how you see it, for sure. But that is not its actual color. As it is emitted is its actual color, “really.”

And the Earth stays spherical too even if it were seen as very squished. Really! Squished and spherical are NOT “both true.”

Edited by owl
Posted

A brief review of points and challenges from the last page which you have avoided addressing:

Swansont:

The shape you measure depends on the frame of reference you are in.

me:

That is your idealism. Earth's shape does not change even if your measurement of it from the well worn extreme frame varies.

 

You:

This is not about measurement error, a surprising mistake for someone who has taught these concepts — an expert — to make.

Me:

No it's not. I have acknowledged many times that the Lorentz transformation formula 'transforms' the possibility of a silly looking squished Earth back to its well known shape. You and others insist that it has no true shape, all shapes as seen from extreme frames being equally valid. Funny you have missed that point after so many repetitions.

 

You deny realism and contend that reality, including Earth's shape, depends on the frame of reference from which it is seen. This proves that your science is based on idealism in denial that cosmos exists and has properties independent of observation and measurement.

Clocks slow down. "Time" is not a process that slows down. Clocks' rates of oscillation vary.

 

 

I've challenged you several times to critique Ross' piece which examines the ontology of your 4D space in depth.

...there is no fourth dimension of space. If you think there is, explain it. Asserting it as a given does not cut it... not an argument for it.

 

You:

“Physics... is based on the premise of measurements being reality. Which you obviously reject.”

Yes. When/if measurement yielded a 1000 mile diameter earth it would be wrong, not "reality."

me

The elapsed time for my dropped ball does not vary, just because two clocks in different frames will have "clocked" the event duration differently. Address that.

 

you:

No, I will not. I gave an scenario and you changed it. I will not defend your straw man.

 

My position contrasts appearances with the natural, intrinsic shapes involved.

Do you understand philosophy of science well enough to realize that the world/cosmos does not depend on our measurements for its reality? I think not.... "measurements being reality."

 

You said, "

We are not at rest with respect to it, but we are not moving with respect to it.”

me:

"That is clearly nonsense."

 

Still is. How did your ‘argument by contradiction’ go again?

Ah, here it is:

“One set of measurements show that I cannot be at rest with respect to it, but another set shows that I am not moving with respect to it.”

 

Well, that sure clears things up! Are you even trying to make sense or just practicing double talk? You are very good at it already.

me:

Do you still think that time travel is possible or not? You said you do, so you reify it. You think "it" changes (slows down) and makes clocks slow down, so you reify it.

 

 

How is time a "dimension?" Things move and we say time elapses as they do.

 

you:

Yes, I deny realism.

me:

Good for you!... A scientist who doesn't believe the world exists as is on its own or has properties of its own independent of measurements, which bestow reality upon the world.

 

you:

No, you have evidence of the earth not being flattened in ONE reference frame.

 

me:

No, all the actual evidence is in favor of a nearly spherical Earth. There is no evidence at all for a flattened Earth. Even if we were able to fly by at near ‘c’ and the Earth *appeared* flattened, it would remain spherical, and the Lorentz transformation would be required to “correct the image.”

 

No, swansont, Earth is not flattened and will never be flattened, even if we ever get to see it from that super fast fly by frame. It will stay nearly spherical and you and your length contraction fanatic colleagues will stay wrong about its "true shape." Yes, it has a true shape which doesn't depend on how we look at it. But up close and at rest with it will always be the best way to look at it for an accurate description.

 

me:

Should we teach our children that the distance to the Sun is somewhere between 10 and 93 million miles, depending on how we measure it, and assume that all frames of reference yield equally accurate results?

You:

Yes, we should.

 

I will leave it to the school boards to decide, and if they teach that crap, I'll get my kids to put my grandkids in a different school. The above is just as ridiculous as ‘creationism’, insisting on a six day period for god to create the world... “and on the seventh day, he rested.”

or...

"Yes, children, earth moves closer to and further away from the sun, depending on how we look at it. The relativity bible tells us so."

 

you:

Yes, I am confused, because you have been using "apparent" and "real" interchangeably, and they don't mean the same thing.

me:

The "real Earth" is nearly spherical. One possible "apparent Earth" could be squished nearly flat. I've used this example until we all must be tired of hearing it, but still you are "confused" about the above distinction.

you:

Measurements can distort reality? Remind me of what you are talking about here.

me:

Reality: Everybody knows the shape of Earth, its exact dimensions and all... from, you know... at rest with it, and living on it as we do and applying our best science of observation.

Yes, measurements can distort reality. If you find a way (go very fast past it) to "measure it" as having a 1000 mile equatorial diameter, that measurement would "distort" its reality.

So science must be intelligent enough to observe and measure from the best possible frame of reference (or translate the differences intelligently.) Of course this flies in the face of the dictum that "there are no preferred frames of reference."

(again)

EARTH IS NOT FLATTENED. An extreme frame of observation can not not make it flattened!

 

You claim here that a flattened Earth is real if you measure it to be flattened. You also claimed that the distance to the Sun varies between 10 and 93 million miles, because our measurements of that distance can vary that much."What we measure is reality."

That is just wrong.

Posted

Perhaps you should brush up on how owl defines "sphere". Personally, I define sphere as "a perfectly round three dimensional thingy including the middle part".

 

You'll notice that in your link, it says that "In mathematics, a careful distinction is made between the sphere [...] and the ball". We were talking about geometry here, not mathematics. It's common sense that a sphere has to have a middle part. You seem to be forgetting that we're in the philosophy forum. We're not "in" mathematics. owl was clearly talking about the Philosophy of Geometry.

 

While you were busy failing Philosophy of Geometry, owl was probably teaching it.

 

 

 

 

 

Geometry IS mathematics.

Posted

If "length is not invariant" means that the shape of Earth and distance to the Sun vary with observation, it is wrong and should not be taught as valid science.

If "time is a nonlinear dimension" means that "it exists" in a way that can slow down (change rates of elapsing) or be "traveled through" it is wrong. (Still no reply to my last "time" challenges.)

And if "there is no preferred frame" means that how we might see things from a near 'c' frame is as valid a description of them as from at rest with them, in the same frame, then that is wrong.

 

 

 

If they see how all three are wrong, they will pass, (ace the course) even though they disagree with these mainstream relativity misconceptions. Saying, 'relativity says so' doesn't make it right. There is a "real world" out there (realism), whether you believe it or not, and it does not depend on how we see it for its reality. Science's job is to see it as accurately as possible.

 

I suppose you don't have to actually believe science is true to pass the class. e.g. a creationist can hypothetically pass a class on evolution as long as s/he can answer the questions. But a smart student would begin to notice that the math they have to do to get the "real" information about particles is undone by the math that has been tacked on to all the physics equations. They might start to question why this is so.

 

For example, they might wonder why the have to declare the kinetic energy of an abject to be zero, because realism teaches that you have to measure properties in the rest frame, but notice that the correction they apply is 1/2mv^2 and envy the students in the "illegal" science class that simply learn that kinetic energy is 1/2mv^2.

 

They might, and I will, ask what philosophy's comment is to the observation that under realism, the laws of physics vary with your frame of reference.

 

 

“Absolute?” Of course we are not talking about your object as the one thing in the cosmos not moving. (Absurd.) Is this a change of goal posts on your part? How about relatively at rest, like in the same frame, not moving relative to an object observed. Science would “prefer” that frame to see what color/wavelength the object is “actually” emitting.

 

You're the one who had claimed to have studied relativity. I merely assumed you were using terminology consistent with that claim.

 

As for what scientists prefer, that depends on the situation. Scientists prefer a system that gets them data.

 

See * above. “Really?” “In your frame” is how you see it, for sure. But that is not its actual color. As it is emitted is its actual color, “really.”

And the Earth stays spherical too even if it were seen as very squished. Really! Squished and spherical are NOT “both true.”

 

Still haven't told me how I can tell the difference between the two photons, by measuring the photons.

 

But shouldn't the "intrinsic" color pf the photon be measured in its rest frame? Of course, physics recognizes (via relativity) that there is no rest frame of a photon.

 

A brief review of points and challenges from the last page which you have avoided addressing:

Virtually all of these have been addressed numerous times.

 

 

"That is clearly nonsense."

 

Still is. How did your ‘argument by contradiction’ go again?

Ah, here it is:

 

 

Well, that sure clears things up! Are you even trying to make sense or just practicing double talk? You are very good at it already.

 

What part is confusing you?

 

 

That is just wrong.

 

That pretty much sums up your argument. You are free to live in your world of realism, convinced that big, bad science doesn't know what the hell it is doing.

 

Meanwhile, GPS works (and not by magic or luck).

Posted

I've followed this discussion for a while but I struggle to understand what the disgareement is actually about.

 

The use of the terms 'realism' and 'idealism' seem to be non-standard, and I cannot see how either in its general philosophical form would be inconsistent with SR. Why does idealism or realism have to say that objects either do or do not have an 'absolute' or fixed shape, mass, velocity etc.? Hell, if one of these 'isms' were found to be inconsistent with SR then we would have a scientific way to decide a philosophical problem.

 

Swansont notes that under realism the laws of physics vary with frame of reference. But surely the laws are invariant. And if they vary, why should they not vary under idealism in the same way as under realism? Is it that 'realsim' here is shorthand for 'naive realism', by which we live in a wysiwyg universe, and then being contrasted with 'naive idealism'?

 

Maybe we're talking 'scientific realism' here. on which I'm a bit vague, and by 'idealism' mean something other than mind-dependent.

 

I'll catch up eventually.

Posted

Geometry IS mathematics.

It is also the study of dimensions, forms, and models, including how/if these models apply to the world/cosmos.

One need not use math to understand the progression of dimensions from point (none) to line (one) to plane (two) to volume (three.) Then, if a fourth spatial dimension is proposed, ontology asks what that describes (how it applies) in the real world, since 3-D covers the three axes of volume or space.

If even more dimensions are proposed, the same inquiry applies with each one. If you call them “ degrees of freedom” then what does this freedom mean as regarding dimensions, as above.

 

 

They might, and I will, ask what philosophy's comment is to the observation that under realism, the laws of physics vary with your frame of reference.

 

You're the one who had claimed to have studied relativity. I merely assumed you were using terminology consistent with that claim.

 

You don't understand realism. You hide behind the phrase "the laws of physics", assuming that length contraction is one of them. So therefore, earth either changes shape, or we can't know its 'true shape', since there is no such thing as 'true shape' according to the above "laws of physics." No doubt the appearance of things changes with frame of reference. Philosophy (realism in this case) distinguishes between an apparently squished earth (or shortened Au) and an actually, in the real world squished earth or shortened Au. You are not, so far, capable of understanding this fundamental difference.

 

As for what scientists prefer, that depends on the situation. Scientists prefer a system that gets them data.

 

I see you omitted "accurate" from "getting data." I taught experimental design, and my "bs detector" just went off. The accurate description of earth comes from an at rest frame with it, not from the near 'c' fly by frame.

 

Still haven't told me how I can tell the difference between the two photons, by measuring the photons.

 

But shouldn't the "intrinsic" color pf the photon be measured in its rest frame? Of course, physics recognizes (via relativity) that there is no rest frame of a photon.

 

Of course we can speak of light (photons) as either waves or particles. So far my replies have focused on light, specifically color, as wavelength. It compresses with object/observer relative movement toward each other. The wavelength as emitted is its intrinsic color.

All of that was a variation of the theme “appears vs is” at your insistence... something we can measure... as relief from earth not changing form even if it were to appear changed (squished.)

Nice bait and switch maneuver.

 

Virtually all of these have been addressed numerous times.

Not so. I could go with one at a time for simplicity. Do you or do you not think that time travel is possible? Do you or do you not think that "time slows down" as in "dilates?" (That sounds like two, but it is one test of your reification of time.)

 

What part is confusing you?

 

I'll pass on bogging this thread down in sorting out your double talk if you refuse to explain it, as I've already challenged.

 

That pretty much sums up your argument. You are free to live in your world of realism, convinced that big, bad science doesn't know what the hell it is doing.

 

Meanwhile, GPS works (and not by magic or luck).

 

Yup. I live the real world where the shape of cosmic bodies does not morph* with observational frame, and distances between them do not shorten even if they look that way to the high speed fly by guy.

*Oh, btw, if they don’t actually morph, since no force is applied by “length contraction” do they (shapes and distances) just remain unknowable since we rate the accuracy of all possible frames the same?

What was your stance on that again? Last I heard you thought that the distance to the sun did vary between 10 and 93 million miles, and you thought that should be taught in school.

 

You continue to intentionally ignore (misrepresenting my position) that I have often agreed on GPS accuracy as adjustment of rate of clocks ticking at different speeds, not ‘proof of time dilation’. But yet you drag it out yet again.

 

I've followed this discussion for a while but I struggle to understand what the disgareement is actually about.

 

The use of the terms 'realism' and 'idealism' seem to be non-standard,...

 

Swansont notes that under realism the laws of physics vary with frame of reference. But surely the laws are invariant. And if they vary, why should they not vary under idealism in the same way as under realism? Is it that 'realsim' here is shorthand for 'naive realism', by which we live in a wysiwyg universe, and then being contrasted with 'naive idealism'?

 

Maybe we're talking 'scientific realism' here. on which I'm a bit vague, and by 'idealism' mean something other than mind-dependent.

 

I'll catch up eventually.

 

Wikipedia (my emphasis):

Realism, Realist or Realistic are terms that describe any manifestation of philosophical realism, the belief that reality exists independently of observers, whether in philosophy itself or in the applied arts and sciences. In this broad sense it is frequently contrasted with Idealism.

...

Scientific realism is, at the most general level, the view that the world described by science (perhaps ideal science) is the real world, as it is, independent of what we might take it to be.

Swansont insists that our measurements are reality.

 

I can see where confusion might arise here. The phrase “perhaps ideal science” above refers, I think, to how close “the world described by science” matches the “reality existing independently of observers” or frames of reference.

 

I say that insisting that measurement (observation)* is* reality... is a contemporary form of idealism, with ‘frame of reference' substituting for “subjective” in classical subjective idealism. This does not deny that frame of reference can be an abstract point of view with no actual ‘subject’ present.

 

I hope this clarifies. Thanks for your comments.

Posted

Just scanned the column on the right and found “time Traveler’s” “update” under Recent Status Updates.

Not a fan of his... I will withhold professional diagnosis... but I really liked one of his statements:

 

“a red car is a red car no matter where it is its still a red car “

Posted

Two quick things:

 

"reality exists independently of observers" is a very different statement from "the shape of the earth is intrinsic, and independent of the frame of the observer". I have never advocated that the existence of anything depends on an observer. What I have said is that what we observe is reality — not an illusion.

 

and

 

"Scientific realism is, at the most general level, the view that the world described by science (perhaps ideal science) is the real world, as it is, independent of what we might take it to be" agrees with me. Science describes the real world. Science as it is, rather than how owl wants it to be.

Posted

...I will withhold professional diagnosis...

You have none to withhold. Get over it and we can be done with this stultifying thread.

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