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What is "miraculous"?
20 years 1 month ago #11668
by makis
Replied by makis on topic Reply from
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
Of course. The experiment parallels the way we first detected air molecules, which we also cannot "see" visually. <hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I suspected all along that you equate unobservability with the inability to either detect visually or through experimenation. Unobservable means something else in physics. It is not a temporary quality assigned to something but a permanent quality that denotes the nature of that something to evade any observation at all, by any means, due to its postulated nature.
For example, absolute space is not observable, since it is not a well-founded phenomenon. This is because all measurements possible are relational in nature, like relative speed and position. There is no way to build an apparatus to detect absolute space.
By the same token, an infinite scale is undetectable. You will need an apparatus of infinite observation capability to detect the whole scale. As soon as you detect something, you will need to postulate something else to explain its presence which is not in the range of capabilities of the current apparatus. You have an infinite regression of causes to detect. Thus, infinite scale is not well-founded from an empirical perspective but is only a rationalization in the same way absolute space is.
But you example has other problems. You failed to describe an apparatus to detect gravitons but instead made a general reference to quantum effects. But before we go to the graviton, can you describe an experiment to detect your electron structure an =d render it necessary, not only sufficient. More importantly, caa you describe any logical deduction or experiment that renders a certain hypothesis about physical reality necessary, in addition to sufficient? Note that I refer to hypotheses.
Finally, I will ask you once more a question I have asked numerous times and you have never answered.
How do you explain the need to postulate ficticious forces in local non-inertial reference frames in your MM (like rotational motion for instance) in order to apply laws of motion of mechanics? Why is it that non-inertial observers need to have a different explanation of phenomena than inertial ones? What is the nature of centrifugal force in your MM? Since all your iniverse is "real", please explain your need to consider ficticious forces. Let's see what new hypothesis you will frame and if that hypothesis will glorify your model or will break it.
It is not what you have presented in MM that is the most questionable, but what you have avoided to deal with that is of more importance.
Makis
Of course. The experiment parallels the way we first detected air molecules, which we also cannot "see" visually. <hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I suspected all along that you equate unobservability with the inability to either detect visually or through experimenation. Unobservable means something else in physics. It is not a temporary quality assigned to something but a permanent quality that denotes the nature of that something to evade any observation at all, by any means, due to its postulated nature.
For example, absolute space is not observable, since it is not a well-founded phenomenon. This is because all measurements possible are relational in nature, like relative speed and position. There is no way to build an apparatus to detect absolute space.
By the same token, an infinite scale is undetectable. You will need an apparatus of infinite observation capability to detect the whole scale. As soon as you detect something, you will need to postulate something else to explain its presence which is not in the range of capabilities of the current apparatus. You have an infinite regression of causes to detect. Thus, infinite scale is not well-founded from an empirical perspective but is only a rationalization in the same way absolute space is.
But you example has other problems. You failed to describe an apparatus to detect gravitons but instead made a general reference to quantum effects. But before we go to the graviton, can you describe an experiment to detect your electron structure an =d render it necessary, not only sufficient. More importantly, caa you describe any logical deduction or experiment that renders a certain hypothesis about physical reality necessary, in addition to sufficient? Note that I refer to hypotheses.
Finally, I will ask you once more a question I have asked numerous times and you have never answered.
How do you explain the need to postulate ficticious forces in local non-inertial reference frames in your MM (like rotational motion for instance) in order to apply laws of motion of mechanics? Why is it that non-inertial observers need to have a different explanation of phenomena than inertial ones? What is the nature of centrifugal force in your MM? Since all your iniverse is "real", please explain your need to consider ficticious forces. Let's see what new hypothesis you will frame and if that hypothesis will glorify your model or will break it.
It is not what you have presented in MM that is the most questionable, but what you have avoided to deal with that is of more importance.
Makis
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20 years 1 month ago #11781
by tvanflandern
Replied by tvanflandern on topic Reply from Tom Van Flandern
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by makis</i>
<br />I suspected all along that you equate unobservability with the inability to either detect visually or through experimentation. Unobservable means something else in physics. It is not a temporary quality assigned to something but a permanent quality that denotes the nature of that something to evade any observation at all, by any means, due to its postulated nature.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">First, you earlier equated “unobservability” and “undetectability” when you said: “It's the typical realist approach in postulating unobservable/undetectable quantities in order to explain the phenomena.”
Second, you argued that gravitons in particular were an example of unobservability when you said: “insisting that you are now sitting on your chair because unobservable particles moving at FTL speeds hit every particle of you body is a rather Tom Potterish scenario.” And you did not acknowledge when I gave a counter-example, showing a type of experiment that can and someday will observe gravitons.
So to continue your harangue against MM, you have had to change definitions and slide the meanings of your sentences, while introducing the occasional strawman along the way. For example:
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">absolute space is not observable, since it is not a well-founded phenomenon. This is because all measurements possible are relational in nature, like relative speed and position. There is no way to build an apparatus to detect absolute space.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">But there is no such concept in MM. You should have used an example from MM. But of course, you could not find one.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">By the same token, an infinite scale is undetectable.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Now you try to make an invalid analogy. All real, tangible entities are made of matter, and logically cannot become infinite. By contrast, concepts easily can become infinite. How many integers are there? What is the tangent of a right angle? How many points comprise a line segment? The concept of infinity helps us to understand reality. But there is nothing real or tangible about concepts. They exist in our minds.
Dimensions are examples of concepts that aid our understanding of reality by providing a way to measure it. But dimensions are necessarily infinite, which simply means “unbounded” or “unlimited”. Take time for example. If time were bounded, then someday all motion in the universe would have to cease, which is illogical; i.e., it leads to a contradiction. The same can be said of space. Either it has a boundary with nothing beyond (illogical), or it is infinite (unbounded). But it is only a concept, so that is okay.
Scale is another dimension, and must likewise be unbounded (infinite) for the same reason: postulating a limit to scale leads to logical paradoxes and contradictions.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Thus, infinite scale is not well-founded from an empirical perspective but is only a rationalization in the same way absolute space is.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">The necessarily unbounded (infinite) nature of scale arises from logic alone. Empiricism has nothing whatever to say about the matter.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">can you describe an experiment to detect your electron structure and render it necessary, not only sufficient. More importantly, can you describe any logical deduction or experiment that renders a certain hypothesis about physical reality necessary, in addition to sufficient? Note that I refer to hypotheses.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">This is a misunderstanding of the nature of physics. No physical hypothesis can ever be proved, only falsified. So sufficiency is the best we can ever attain in physics. There is no way to exclude the possibility that the whole visible universe is a holodeck illusion, and that the laws of physics will suddenly change tomorrow morning. But so far, there is also not a shred of credible evidence to support that notion either. So until something comes along that we cannot explain, it is not useful to think in terms of magic or miracles when doing physics because that way of thinking interferes with our quest to find real causes and effect so we can achieve predictability.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">How do you explain the need to postulate fictitious forces in local non-inertial reference frames in your MM (like rotational motion for instance) in order to apply laws of motion of mechanics? Why is it that non-inertial observers need to have a different explanation of phenomena than inertial ones? What is the nature of centrifugal force in your MM? Since your entire universe is "real", please explain your need to consider fictitious forces. Let's see what new hypothesis you will frame and if that hypothesis will glorify your model or will break it.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">This is a very vague question because pseudo-forces such as centrifugal force are not real forces by definition, They are illusions created by the choice of non-inertial reference frames. For example, if I swing water in a pail (held by the handle) around in a circle, there is no force pushing the water molecules into the pail. But each molecule continually tries to move in a straight line. So it is really the pail, forced to move in a circle, that pushes against the water molecules and forces them to change the direction they are otherwise inclined to move in. That is the real force -- a centripetal one imposed by the pail.
So there is never any “need” for pseudo-forces. But much like dimensions and other concepts that have no real existence outside the mind, they serve as a useful aid in making predictions.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">It is not what you have presented in MM that is the most questionable, but what you have avoided to deal with that is of more importance.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">If you can find something relevant in that category, don’t hesitate to mention bring it up. -|Tom|-
<br />I suspected all along that you equate unobservability with the inability to either detect visually or through experimentation. Unobservable means something else in physics. It is not a temporary quality assigned to something but a permanent quality that denotes the nature of that something to evade any observation at all, by any means, due to its postulated nature.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">First, you earlier equated “unobservability” and “undetectability” when you said: “It's the typical realist approach in postulating unobservable/undetectable quantities in order to explain the phenomena.”
Second, you argued that gravitons in particular were an example of unobservability when you said: “insisting that you are now sitting on your chair because unobservable particles moving at FTL speeds hit every particle of you body is a rather Tom Potterish scenario.” And you did not acknowledge when I gave a counter-example, showing a type of experiment that can and someday will observe gravitons.
So to continue your harangue against MM, you have had to change definitions and slide the meanings of your sentences, while introducing the occasional strawman along the way. For example:
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">absolute space is not observable, since it is not a well-founded phenomenon. This is because all measurements possible are relational in nature, like relative speed and position. There is no way to build an apparatus to detect absolute space.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">But there is no such concept in MM. You should have used an example from MM. But of course, you could not find one.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">By the same token, an infinite scale is undetectable.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Now you try to make an invalid analogy. All real, tangible entities are made of matter, and logically cannot become infinite. By contrast, concepts easily can become infinite. How many integers are there? What is the tangent of a right angle? How many points comprise a line segment? The concept of infinity helps us to understand reality. But there is nothing real or tangible about concepts. They exist in our minds.
Dimensions are examples of concepts that aid our understanding of reality by providing a way to measure it. But dimensions are necessarily infinite, which simply means “unbounded” or “unlimited”. Take time for example. If time were bounded, then someday all motion in the universe would have to cease, which is illogical; i.e., it leads to a contradiction. The same can be said of space. Either it has a boundary with nothing beyond (illogical), or it is infinite (unbounded). But it is only a concept, so that is okay.
Scale is another dimension, and must likewise be unbounded (infinite) for the same reason: postulating a limit to scale leads to logical paradoxes and contradictions.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Thus, infinite scale is not well-founded from an empirical perspective but is only a rationalization in the same way absolute space is.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">The necessarily unbounded (infinite) nature of scale arises from logic alone. Empiricism has nothing whatever to say about the matter.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">can you describe an experiment to detect your electron structure and render it necessary, not only sufficient. More importantly, can you describe any logical deduction or experiment that renders a certain hypothesis about physical reality necessary, in addition to sufficient? Note that I refer to hypotheses.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">This is a misunderstanding of the nature of physics. No physical hypothesis can ever be proved, only falsified. So sufficiency is the best we can ever attain in physics. There is no way to exclude the possibility that the whole visible universe is a holodeck illusion, and that the laws of physics will suddenly change tomorrow morning. But so far, there is also not a shred of credible evidence to support that notion either. So until something comes along that we cannot explain, it is not useful to think in terms of magic or miracles when doing physics because that way of thinking interferes with our quest to find real causes and effect so we can achieve predictability.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">How do you explain the need to postulate fictitious forces in local non-inertial reference frames in your MM (like rotational motion for instance) in order to apply laws of motion of mechanics? Why is it that non-inertial observers need to have a different explanation of phenomena than inertial ones? What is the nature of centrifugal force in your MM? Since your entire universe is "real", please explain your need to consider fictitious forces. Let's see what new hypothesis you will frame and if that hypothesis will glorify your model or will break it.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">This is a very vague question because pseudo-forces such as centrifugal force are not real forces by definition, They are illusions created by the choice of non-inertial reference frames. For example, if I swing water in a pail (held by the handle) around in a circle, there is no force pushing the water molecules into the pail. But each molecule continually tries to move in a straight line. So it is really the pail, forced to move in a circle, that pushes against the water molecules and forces them to change the direction they are otherwise inclined to move in. That is the real force -- a centripetal one imposed by the pail.
So there is never any “need” for pseudo-forces. But much like dimensions and other concepts that have no real existence outside the mind, they serve as a useful aid in making predictions.
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">It is not what you have presented in MM that is the most questionable, but what you have avoided to deal with that is of more importance.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">If you can find something relevant in that category, don’t hesitate to mention bring it up. -|Tom|-
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20 years 1 month ago #11670
by makis
Replied by makis on topic Reply from
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
This is a very vague question because pseudo-forces such as centrifugal force are not real forces by definition, They are illusions created by the choice of non-inertial reference frames. For example, if I swing water in a pail (held by the handle) around in a circle, there is no force pushing the water molecules into the pail. But each molecule continually tries to move in a straight line. So it is really the pail, forced to move in a circle, that pushes against the water molecules and forces them to change the direction they are otherwise inclined to move in. That is the real force -- a centripetal one imposed by the pail.
So there is never any “need” for pseudo-forces. But much like dimensions and other concepts that have no real existence outside the mind, they serve as a useful aid in making predictions.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
"The existence of non-inertial frames comes down to saying that there is motion with no apparent cause. F=ma can be made to apply in all frames if certain "ficticious" forces are allowed to operate..."
Ref: Peacock John, "Cosmological Physics".
Maybe another example will convince you:
There is a man sitting on a chair that has a horizontal table top attached to it and can rotate with the char about an axis perpendicular to the table top. The man is holding a dynamometer attached to a mass m and the system rests on the table top. If we set the chair in rotation, the man observes a force on the dynamometer which is equal to F = m x omega^2 x r, where omega is the angular speed and r the distance to the mass.
A. For an inertial observer: The mass is on a uniform circular motion, therefore accelerates and that requires a force equal to F = m x a = m x v^2/r = m x omega^2 x r, this force is what the dynamometer reads exactly and imposed by the man on the mass.
B. For a rotating observer on the table top: The mass is at rest, therefore it does not accelerate. For that to happen, the resultant force on the mass must be zero, But there is a force already observed on the mass and measured by the dynamometer. Therefore, there must be another force F' on the mass, equal and opposite to the masured force, thus F' = - m x omega^2 x r. This force, which does not exist in reality, must be assumed by the rotating observer in order to apply the second law of motion. This ficticious force is called centrifugal.
Therefore, as Peacock says in the reference above, it seems there is motion with no apparent cause for observers in non-inertial reference frames.
You make the old, really outdated, argument that these ficticious forces arise from an incorrect choice of reference frame. This is the same statement used by Newton and it becomes obvious that you operate in the Newtonian mechanics domain. Still, according to all and numerous Newton opponents, those ficticious forces must have a direct explanation. Not the explanation you try to give and arises when one assumes already the existence of absolute inertial space.
Thus, without wasting time here, it is obvious that your attempt to move in the borders of absolutism and relationism, are met with some failures. This is because, although you have postulated a cosmology, you have failed to ground the physics of your model to some notion of a cause that is invariant wrt to the choice of refernce frame. This the the same type of failure Leibniz faced when he defined mv^2 as the cause of motion. You are stuck with Newtonian mechanics and Lorentz Relativity but that fails to satisfy your causality principle that:
"every effect must have a proximate antecedant cause".
I just gave you an example in which the motion of a mass is either explained by a ficticious, non-existent, cause or seems to occur without a cause depending on the perspective of an observer.
Therefore, your model must be abandoned since experimental observation invalidates one of its principles, i.e. the causality principle.
Or, change the principle to read:
"every effect has a proximate antecedant cause or no cause at all".
That comes better to agree with experimental evidence in non-inertial reference frames and quantum mechanics experiments involving particle entaglement and action-at-a-distance.
But for now, principles and observations contradict each other in your model. Save the unobservables postulated.
Conclusion: your common sensical approach to physics and cosmology is trivially problematic in its foundation. Hint:
a. either there is an absolute space and external to the universe forces (or hidden variables) or
b. three dimensions are not enough to describe the world.
Modern physics goes for b. GR postulates a 4-D spacetime and M-Theory 26 or so dimensions ( I lost count it seems).
To surprise you, for the first time in these boards, I will state my own opinion about this. I go for choice a. In that respect, I agree with you that GR is a non-sensical approach, although covariance solves the observational problems by making inertial motion acausal. I justify my rejection of GR on the basis that its spacetime structure is unobservable. But your approach is as problematic, it turns out even more than GR is. If someone must reject GR, she must reject MM twice.
All the best.
Makis
This is a very vague question because pseudo-forces such as centrifugal force are not real forces by definition, They are illusions created by the choice of non-inertial reference frames. For example, if I swing water in a pail (held by the handle) around in a circle, there is no force pushing the water molecules into the pail. But each molecule continually tries to move in a straight line. So it is really the pail, forced to move in a circle, that pushes against the water molecules and forces them to change the direction they are otherwise inclined to move in. That is the real force -- a centripetal one imposed by the pail.
So there is never any “need” for pseudo-forces. But much like dimensions and other concepts that have no real existence outside the mind, they serve as a useful aid in making predictions.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
"The existence of non-inertial frames comes down to saying that there is motion with no apparent cause. F=ma can be made to apply in all frames if certain "ficticious" forces are allowed to operate..."
Ref: Peacock John, "Cosmological Physics".
Maybe another example will convince you:
There is a man sitting on a chair that has a horizontal table top attached to it and can rotate with the char about an axis perpendicular to the table top. The man is holding a dynamometer attached to a mass m and the system rests on the table top. If we set the chair in rotation, the man observes a force on the dynamometer which is equal to F = m x omega^2 x r, where omega is the angular speed and r the distance to the mass.
A. For an inertial observer: The mass is on a uniform circular motion, therefore accelerates and that requires a force equal to F = m x a = m x v^2/r = m x omega^2 x r, this force is what the dynamometer reads exactly and imposed by the man on the mass.
B. For a rotating observer on the table top: The mass is at rest, therefore it does not accelerate. For that to happen, the resultant force on the mass must be zero, But there is a force already observed on the mass and measured by the dynamometer. Therefore, there must be another force F' on the mass, equal and opposite to the masured force, thus F' = - m x omega^2 x r. This force, which does not exist in reality, must be assumed by the rotating observer in order to apply the second law of motion. This ficticious force is called centrifugal.
Therefore, as Peacock says in the reference above, it seems there is motion with no apparent cause for observers in non-inertial reference frames.
You make the old, really outdated, argument that these ficticious forces arise from an incorrect choice of reference frame. This is the same statement used by Newton and it becomes obvious that you operate in the Newtonian mechanics domain. Still, according to all and numerous Newton opponents, those ficticious forces must have a direct explanation. Not the explanation you try to give and arises when one assumes already the existence of absolute inertial space.
Thus, without wasting time here, it is obvious that your attempt to move in the borders of absolutism and relationism, are met with some failures. This is because, although you have postulated a cosmology, you have failed to ground the physics of your model to some notion of a cause that is invariant wrt to the choice of refernce frame. This the the same type of failure Leibniz faced when he defined mv^2 as the cause of motion. You are stuck with Newtonian mechanics and Lorentz Relativity but that fails to satisfy your causality principle that:
"every effect must have a proximate antecedant cause".
I just gave you an example in which the motion of a mass is either explained by a ficticious, non-existent, cause or seems to occur without a cause depending on the perspective of an observer.
Therefore, your model must be abandoned since experimental observation invalidates one of its principles, i.e. the causality principle.
Or, change the principle to read:
"every effect has a proximate antecedant cause or no cause at all".
That comes better to agree with experimental evidence in non-inertial reference frames and quantum mechanics experiments involving particle entaglement and action-at-a-distance.
But for now, principles and observations contradict each other in your model. Save the unobservables postulated.
Conclusion: your common sensical approach to physics and cosmology is trivially problematic in its foundation. Hint:
a. either there is an absolute space and external to the universe forces (or hidden variables) or
b. three dimensions are not enough to describe the world.
Modern physics goes for b. GR postulates a 4-D spacetime and M-Theory 26 or so dimensions ( I lost count it seems).
To surprise you, for the first time in these boards, I will state my own opinion about this. I go for choice a. In that respect, I agree with you that GR is a non-sensical approach, although covariance solves the observational problems by making inertial motion acausal. I justify my rejection of GR on the basis that its spacetime structure is unobservable. But your approach is as problematic, it turns out even more than GR is. If someone must reject GR, she must reject MM twice.
All the best.
Makis
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20 years 1 month ago #11681
by Jim
Replied by Jim on topic Reply from
Makis, Why make a case for or against a model when there are real issues being buried in the process? This seems a bit pointless and what good does it do? After all it is just a model.
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20 years 2 weeks ago #11786
by makis
Replied by makis on topic Reply from
<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by makis</i>
<br /><blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
This is a very vague question because pseudo-forces such as centrifugal force are not real forces by definition, They are illusions created by the choice of non-inertial reference frames. For example, if I swing water in a pail (held by the handle) around in a circle, there is no force pushing the water molecules into the pail. But each molecule continually tries to move in a straight line. So it is really the pail, forced to move in a circle, that pushes against the water molecules and forces them to change the direction they are otherwise inclined to move in. That is the real force -- a centripetal one imposed by the pail.
So there is never any “need” for pseudo-forces. But much like dimensions and other concepts that have no real existence outside the mind, they serve as a useful aid in making predictions.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
"The existence of non-inertial frames comes down to saying that there is motion with no apparent cause. F=ma can be made to apply in all frames if certain "ficticious" forces are allowed to operate..."
Ref: Peacock John, "Cosmological Physics".
Maybe another example will convince you:
There is a man sitting on a chair that has a horizontal table top attached to it and can rotate with the char about an axis perpendicular to the table top. The man is holding a dynamometer attached to a mass m and the system rests on the table top. If we set the chair in rotation, the man observes a force on the dynamometer which is equal to F = m x omega^2 x r, where omega is the angular speed and r the distance to the mass.
A. For an inertial observer: The mass is on a uniform circular motion, therefore accelerates and that requires a force equal to F = m x a = m x v^2/r = m x omega^2 x r, this force is what the dynamometer reads exactly and imposed by the man on the mass.
B. For a rotating observer on the table top: The mass is at rest, therefore it does not accelerate. For that to happen, the resultant force on the mass must be zero, But there is a force already observed on the mass and measured by the dynamometer. Therefore, there must be another force F' on the mass, equal and opposite to the masured force, thus F' = - m x omega^2 x r. This force, which does not exist in reality, must be assumed by the rotating observer in order to apply the second law of motion. This ficticious force is called centrifugal.
Therefore, as Peacock says in the reference above, it seems there is motion with no apparent cause for observers in non-inertial reference frames.
You make the old, really outdated, argument that these ficticious forces arise from an incorrect choice of reference frame. This is the same statement used by Newton and it becomes obvious that you operate in the Newtonian mechanics domain. Still, according to all and numerous Newton opponents, those ficticious forces must have a direct explanation. Not the explanation you try to give and arises when one assumes already the existence of absolute inertial space.
Thus, without wasting time here, it is obvious that your attempt to move in the borders of absolutism and relationism, are met with some failures. This is because, although you have postulated a cosmology, you have failed to ground the physics of your model to some notion of a cause that is invariant wrt to the choice of refernce frame. This the the same type of failure Leibniz faced when he defined mv^2 as the cause of motion. You are stuck with Newtonian mechanics and Lorentz Relativity but that fails to satisfy your causality principle that:
"every effect must have a proximate antecedant cause".
I just gave you an example in which the motion of a mass is either explained by a ficticious, non-existent, cause or seems to occur without a cause depending on the perspective of an observer.
Therefore, your model must be abandoned since experimental observation invalidates one of its principles, i.e. the causality principle.
Or, change the principle to read:
"every effect has a proximate antecedant cause or no cause at all".
That comes better to agree with experimental evidence in non-inertial reference frames and quantum mechanics experiments involving particle entaglement and action-at-a-distance.
But for now, principles and observations contradict each other in your model. Save the unobservables postulated.
Conclusion: your common sensical approach to physics and cosmology is trivially problematic in its foundation. Hint:
a. either there is an absolute space and external to the universe forces (or hidden variables) or
b. three dimensions are not enough to describe the world.
Modern physics goes for b. GR postulates a 4-D spacetime and M-Theory 26 or so dimensions ( I lost count it seems).
To surprise you, for the first time in these boards, I will state my own opinion about this. I go for choice a. In that respect, I agree with you that GR is a non-sensical approach, although covariance solves the observational problems by making inertial motion acausal. I justify my rejection of GR on the basis that its spacetime structure is unobservable. But your approach is as problematic, it turns out even more than GR is. If someone must reject GR, she must reject MM twice.
All the best.
Makis
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Should I suppose that maybe TVF is still sitting on a rotating table spinning around trying to find the answer to the above questions?
Makis
<br /><blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by tvanflandern</i>
This is a very vague question because pseudo-forces such as centrifugal force are not real forces by definition, They are illusions created by the choice of non-inertial reference frames. For example, if I swing water in a pail (held by the handle) around in a circle, there is no force pushing the water molecules into the pail. But each molecule continually tries to move in a straight line. So it is really the pail, forced to move in a circle, that pushes against the water molecules and forces them to change the direction they are otherwise inclined to move in. That is the real force -- a centripetal one imposed by the pail.
So there is never any “need” for pseudo-forces. But much like dimensions and other concepts that have no real existence outside the mind, they serve as a useful aid in making predictions.
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"The existence of non-inertial frames comes down to saying that there is motion with no apparent cause. F=ma can be made to apply in all frames if certain "ficticious" forces are allowed to operate..."
Ref: Peacock John, "Cosmological Physics".
Maybe another example will convince you:
There is a man sitting on a chair that has a horizontal table top attached to it and can rotate with the char about an axis perpendicular to the table top. The man is holding a dynamometer attached to a mass m and the system rests on the table top. If we set the chair in rotation, the man observes a force on the dynamometer which is equal to F = m x omega^2 x r, where omega is the angular speed and r the distance to the mass.
A. For an inertial observer: The mass is on a uniform circular motion, therefore accelerates and that requires a force equal to F = m x a = m x v^2/r = m x omega^2 x r, this force is what the dynamometer reads exactly and imposed by the man on the mass.
B. For a rotating observer on the table top: The mass is at rest, therefore it does not accelerate. For that to happen, the resultant force on the mass must be zero, But there is a force already observed on the mass and measured by the dynamometer. Therefore, there must be another force F' on the mass, equal and opposite to the masured force, thus F' = - m x omega^2 x r. This force, which does not exist in reality, must be assumed by the rotating observer in order to apply the second law of motion. This ficticious force is called centrifugal.
Therefore, as Peacock says in the reference above, it seems there is motion with no apparent cause for observers in non-inertial reference frames.
You make the old, really outdated, argument that these ficticious forces arise from an incorrect choice of reference frame. This is the same statement used by Newton and it becomes obvious that you operate in the Newtonian mechanics domain. Still, according to all and numerous Newton opponents, those ficticious forces must have a direct explanation. Not the explanation you try to give and arises when one assumes already the existence of absolute inertial space.
Thus, without wasting time here, it is obvious that your attempt to move in the borders of absolutism and relationism, are met with some failures. This is because, although you have postulated a cosmology, you have failed to ground the physics of your model to some notion of a cause that is invariant wrt to the choice of refernce frame. This the the same type of failure Leibniz faced when he defined mv^2 as the cause of motion. You are stuck with Newtonian mechanics and Lorentz Relativity but that fails to satisfy your causality principle that:
"every effect must have a proximate antecedant cause".
I just gave you an example in which the motion of a mass is either explained by a ficticious, non-existent, cause or seems to occur without a cause depending on the perspective of an observer.
Therefore, your model must be abandoned since experimental observation invalidates one of its principles, i.e. the causality principle.
Or, change the principle to read:
"every effect has a proximate antecedant cause or no cause at all".
That comes better to agree with experimental evidence in non-inertial reference frames and quantum mechanics experiments involving particle entaglement and action-at-a-distance.
But for now, principles and observations contradict each other in your model. Save the unobservables postulated.
Conclusion: your common sensical approach to physics and cosmology is trivially problematic in its foundation. Hint:
a. either there is an absolute space and external to the universe forces (or hidden variables) or
b. three dimensions are not enough to describe the world.
Modern physics goes for b. GR postulates a 4-D spacetime and M-Theory 26 or so dimensions ( I lost count it seems).
To surprise you, for the first time in these boards, I will state my own opinion about this. I go for choice a. In that respect, I agree with you that GR is a non-sensical approach, although covariance solves the observational problems by making inertial motion acausal. I justify my rejection of GR on the basis that its spacetime structure is unobservable. But your approach is as problematic, it turns out even more than GR is. If someone must reject GR, she must reject MM twice.
All the best.
Makis
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Should I suppose that maybe TVF is still sitting on a rotating table spinning around trying to find the answer to the above questions?
Makis
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20 years 2 weeks ago #11736
by north
Replied by north on topic Reply from
makis
but it seems to me that this is a matter of perspective. now what if this observer on the table could compare his perspective to his outer surroundings. he would only not know that he is spinning if he could not turn around and compare his position to an outside enviroment. looking within perhaps he wouldn't but looking without he would notice. much like to me in our position on earth we don't relise that we are spining until looking out to the night sky.
but it seems to me that this is a matter of perspective. now what if this observer on the table could compare his perspective to his outer surroundings. he would only not know that he is spinning if he could not turn around and compare his position to an outside enviroment. looking within perhaps he wouldn't but looking without he would notice. much like to me in our position on earth we don't relise that we are spining until looking out to the night sky.
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