Is Einstein's 1905 light postulate true? An equivalent question: Can a sentient being "jump, within a minute (of his experienced time) arbitrarily far in the future, say sixty million years ahead, and see, and be part of, what (will) happen then on Earth"?
Thibault Damour: "The paradigm of the special relativistic upheaval of the usual concept of time is the twin paradox. Let us emphasize that this striking example of time dilation proves that time travel (towards the future) is possible. As a gedanken experiment (if we neglect practicalities such as the technology needed for reaching velocities comparable to the velocity of light, the cost of the fuel and the capacity of the traveller to sustain high accelerations), it shows that a sentient being can jump, "within a minute" (of his experienced time) arbitrarily far in the future, say sixty million years ahead, and see, and be part of, what (will) happen then on Earth. This is a clear way of realizing that the future "already exists" (as we can experience it "in a minute"). No wonder that many people, attached to the usual idea of an external flow of time, refused to believe that the travelling twin will come back younger than his sedentary brother."
Pentcho Valev pvalev@yahoo.com
Paul Reed replied on Oct. 25, 2011 @ 08:43 GMT
Pentcho
I do not understand how this post makes my question “more concrete”. It just avoids addressing the question (though I do recognise the fact that you have responded).
What you are describing is a simple Doppler effect. I have posted these two paragraphs several times, mainly in connection with the so-called Twin Paradox, but will do so again. Here is an explanation of this particular optical illusion:
“Light is the information medium in an experience based on sight. As light travels, there is a delay between the existence of a state and its perception. That delay will vary as a function of the individual spaces involved, and the speed with which the light travelled in each experience. Whilst the perceived order of sequence will never vary, assuming that light has a reasonable degree of constancy of movement (ie is not fundamentally erratic).
The perceived rate of change of a sequence will remain the same, so long as the on-going relative spatial position remains constant amongst everything involved. Because, while the value of the delay is different depending on each individual space, it remains constant. However, when relative individual space is altering, then the perceived rate of change alters, because the delay is ever increasing (or decreasing) at a rate which depends on the rate at which individual spaces are altering. It is a perceptual illusion. The intrinsic rate of change (duration, in reality) in the sequence being experienced does not alter, either in order to create this effect, or as a consequence of this effect being realised”.
[Note: the possible effect of length contraction is not accounted for in the above statement].
This has nothing to do with what I am talking about (which was in Neutrino your thread 10/10 10.17). Which is the concept that light always travels at c wrt observer.
Paul
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John Merryman replied on Oct. 25, 2011 @ 16:06 GMT
Paul,
The point is that as the observer accelerates, their clock slows proportionally, because their internal atomic function slows. Since electrons move internally at c, the combination of velocity and internal motion cannot exceed c, so the theoretical observer will exist in a slower clock frame and thus the light will still appear to move at c, relative to their frame.
The problem is this assumes spacetime is a fundamentally real geometry that actually governs what is happening, rather than simply modeling what is happening. This introduces all sorts of theoretical issues, from blocktime, to wormholes to even the conceptual basis for an expanding universe.
Logically a simpler solution would be that space amounts to an inertial state that sets limits on how fast energy can propagate, rather than simply being entirely relativistic. A simple thought experiment to show this might be possible is to ask yourself if something spinning in a complete vacuum would have centrifugal force? How would we know, without some outside reference, if it was spinning? Yet to argue that space is entirely relativistic would mean that simply detecting an outside reference would be the only proof it is spinning, so that would have to be the cause of centrifugal force. Obviously this is wrong, so the logical conclusion is that space has some inertial effect.
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T H Ray replied on Oct. 25, 2011 @ 16:37 GMT
John Merryman replied on Oct. 25, 2011 @ 16:56 GMT
Tom,
I get a DNS lookup error on that link.
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John Merryman replied on Oct. 25, 2011 @ 17:01 GMT
John Merryman replied on Oct. 25, 2011 @ 17:52 GMT
Tom,
That is a very interesting and concise description, especially since it is by the Man himself, but I don't see how it addresses the question of centrifugal force that I raised. Now I might well have missed how it could be extracted from it and would be interested to have it clarified.
This description encapsulates my point about spacetime:
"In the first place we must guard against the opinion that the four-dimensionality of reality has been newly introduced for the first time by this theory. Even in classical physics the event is localised by four numbers, three spatial co-ordinates and a time co-ordinate; the totality of physical "events" is thus thought of as being embedded in a four-dimensional continuous manifold. But on the basis of classical mechanics this four-dimensional continuum breaks up objectively into the one-dimensional time and into three-dimensional spatial sections, only the latter of which contain simultaneous events. This resolution is the same for all inertial systems. The simultaneity of two definite events with reference to one inertial system involves the simultaneity of these events in reference to all inertial systems. This is what is meant when we say that the time of classical mechanics is absolute. According to the special theory of relativity it is otherwise.
The sum total of events which are simultaneous with a selected event exist, it is true, in relation to a particular inertial system, but no longer independently of the choice of the inertial system. The four-dimensional continuum is now no longer resolvable objectively into sections, all of which contain simultaneous events; "now" loses for the spatiaIly extended world its objective meaning. It is because of this that space and time must be regarded as a four-dimensional continuum that is objectively unresolvable, if it is desired to express the purport of objective relations without unnecessary conventional arbitrariness."
It still assumes time to be a fundamental vector along which events exist and simply dispenses with the non-simultaneity of perception by describing this vector as part of a four dimensional spacetime geometry. My point is that we shouldn't treat that timeline as fundamental, but as an effect of the changing configuration of what materially exists and it is the events which are the ephemeral quality, transitioning from future to past. Thus we can have variable clock rates, relative perception of events and all the other measurable quantities of relativity, without having the discard the present as a physical reality, or all the wormhole type speculation arising from a theoretically malleable spacetime.
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Georgina Parry replied on Oct. 25, 2011 @ 20:15 GMT
Tom,
your link was flagged as a known malicious web site.
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T H Ray replied on Oct. 25, 2011 @ 20:47 GMT
Well, that's strange. I got no warning from my very well filtered work computer. But I can't access the page from the server I'm on now. Hopefully, Brandon will remove the post. The material is public domain Einstein publications.
Tom
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Georgina Parry replied on Oct. 25, 2011 @ 21:02 GMT
Sorry Tom, maybe something has happened to it recently. I was given a number of security threat warnings.
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John Merryman replied on Oct. 26, 2011 @ 03:10 GMT
Other than the extra http://, the link worked for me.
Interesting to see the basis of spacetime, in Einstein's own words, is just the three spatial coordinates and the narrative timeline. No, it certainly wasn't new, since it's the conceptual foundation of history.
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Paul Reed replied on Oct. 26, 2011 @ 06:02 GMT
John
Your post 25/10 16.06
The point is that, according to Einstein, et al, under acceleration (or de-deceleration), the force that caused that changing momentum, also causes the length of matter to alter. But only when it is changing, ie it is always the same dimension when travelling at a constant speed, irrespective of that speed. Now, how that compression (or whatever one wants to call it) affects the actual functioning of the matter, whether it be a timing device or whatever, is another matter. The point is that, if length dimension has altered, then it will not arrive at a point in space at the time expected, if one fails to realise this effect is occurring. One inadvertently ends up comparing apple with squashed apple, ie not like for like.
The next point is that, why is it that electrons (or anything else allegedly doing so) travel at c, and why does nothing travel faster than c? Is it because the theory says so, and/or because we observe with light? Remember, we do not see reality, we receive a light based representation of it. The two are different. [I did get a dialogue going on why c in several equations, but that was another one that died out before it really got going].
Which brings me back to my question. Either:
a) light travels at the same speed in all circumstances
b) light travels at different speeds due to circumstances
If a), then why all this discussion? Light always takes the same amount of time to travel the same distance, irrespective of circumstances.
If b), then how does a variance result from the influence of an observer? Light is independent of observer, indeed it ceases to exist at the point in time when it makes contact with eyeball.
Paul
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Paul Reed replied on Oct. 26, 2011 @ 06:13 GMT
John
The reason for inertial system is because that is the one that is not undergoing (supposedly) length contraction (or expansion). So before one can compare (relativity)either the matter has to be 'at rest/in equilibrium', or one applies a compensation factor (transformation) to establish what it would be, if it was not being so affected. It is all about timing.
Paul
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John Merryman replied on Oct. 26, 2011 @ 11:28 GMT
Paul,
The ways in which relativity describes the many optical and physical effects and their various permutations are many. My only real observation is that spacetime amounts to a very clever modeling of these effects, rather than existing as some underlaying reality determining them. I base this on the observation that it tries to include the normal intuitive understanding of time as a progression from past to future, when the logical physical explanation is that it's the changing configuration of energy that coalesces particular events and then replaces them, such that it is the future becoming the past.
Because this would mean time is not part of that underlaying geometry, but rather an effect of motion, rate of change, it is similar to temperature, level of activity, rather than space.
Since the time dynamic is no longer on a level with space, this means space has no physically dynamic properties. Since it has no physical definition, it has no physical limitation and therefore is infinite. Since it has no physical dynamic, it is inert.
Such properties as distance, volume, velocity,expansion, contraction, etc, emerge from the interactions of energy and limitations imposed by the definitions of energy and mass, in space.
There is this fluctuating vacuum. It is meaningless to suppose a beginning or end, because such concepts/limits emerge from this process and any attempt to so define the process only raises questions about what is outside those imposed limitations.
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T H Ray replied on Oct. 26, 2011 @ 13:15 GMT
John,
You wrote " ... to argue that space is entirely relativistic would mean that simply detecting an outside reference would be the only proof it is spinning, so that would have to be the cause of centrifugal force. Obviously this is wrong, so the logical conclusion is that space has some inertial effect."
If that were true, Newton would have been right about the spinning bucket experiment. He wasn't.
Tom
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T H Ray replied on Oct. 26, 2011 @ 13:20 GMT
Paul,
Light does travel at different speeds according to circumstances (i.e., physical conditions). That's why a stick submerged in water appears bent -- it takes longer for light to travel through water than through air, so the rays from the submerged part reach the eye later than those from the unsubmerged part.
The invariance of the speed of light is a vacuum measurment.
Tom
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Paul Reed replied on Oct. 26, 2011 @ 17:02 GMT
John
Your post 26/10 11.28
The ways in which ‘relativity’ describes this, that, or the other, may be many (I am not sure that is so), but it does describe the effects very specifically, ie it gives them mathematical factors. In other words one cannot just have a ‘pick and mix’ approach and sweep ‘awkward’ bits under the carpet. I would have to have another look at Minkowski to remind myself, but I believe my initial view was that this was OK, IF time was not reified as a ‘dimension’, ie the model presumes spatial dimensions changing (timing).
You are right, as I have said before, to talk ultimately about motion/energy, so long as this is at the lowest level, because reality is elementary particles in motion. But I think, and taking into account your other posts, you are not really agreeing with my point about there being no such thing as time. There is just change (which at the lowest level boils down to motion), which happens at different rates, and we can time it.
This is substantiated by your next sentence: “Since the time dynamic is no longer on a level with space, this means space has no physically dynamic properties”. At any given point, space still has a dynamic, it can have three values. All that has happened at any point is that movement has ceased (obviously, because you need more than one point). So in that circumstance, one is not able to appreciate space through movement. But it still has three possibilities, whereas time has one, which indicates that what we refer to as time is in fact, change. And that does not happen if you consider reality, point by point.
Paul
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John Merryman replied on Oct. 26, 2011 @ 17:15 GMT
Tom,
That's why I said in a vacuum. The spinning bucket exists in multiple frames, most especially that of the earth's gravity. The other example would be the
rotating spheres. Where it is isolated from all the various potential centripedal effects etc.
Here is Mach's argument for relative motion:
"For me, only relative motions exist…When a body rotates relatively to the fixed stars, centrifugal forces are produced; when it rotates relatively to some different body and not relative to the fixed stars, no centrifugal forces are produced."
— Ernst Mach; as quoted by Ciufolini and Wheeler: Gravitation and Inertia, p. 387
So what defines the "fixed stars?" It seems he is describing inertial space. What if those stars are so far away as to have minimal gravitational effect, is inertia reduced?
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Paul Reed replied on Oct. 26, 2011 @ 17:17 GMT
Ray
Your post 26/10 13.20
I know light travels at different speeds, that is why I keep flogging this question!!
This has its genesis in various threads, but mainly Neutrino Black Magic: Pentcho 10/10. 10.17. Having established what Einstein actually said, as opposed to what is assumed, I then went on to address this notion of ‘always c wrt observer’. My latest attempt was somewhat side-tracked by Pentcho making my enquiry “more concrete” by a) not answering the question, b) telling me about a Doppler effect in light, which I know all about-then we drift to Twin Paradox.
SO!!!! The question is:
Either:
a) light travels at the same speed in all circumstances
b) light travels at different speeds due to circumstances
If a), then why all this discussion? Light always takes the same amount of time to travel the same distance, irrespective of circumstances.
If b), then how does a variance result from the influence of an observer? Light is independent of observer, indeed it ceases to exist at the point in time when it makes contact with eyeball.
Answers on a postcard, anyone?
Paul
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John Merryman replied on Oct. 26, 2011 @ 17:34 GMT
Paul,
I am in agreement that time is change and measuring time is measuring rate of change. My point is that activity does have another primary method of detection and that would be level of activity, ie, temperature.
Not that either of these effects could be in any way isolated from motion, even if measuring them is subjective. Much as it would be equally difficult to have space without distance or volume, even if any measure is subjective.
In fact, I would describe the left hemisphere of the brain, the linear, rational side, as a form of clock, in that it processes sequence, while the right hemisphere, the non-linear, intuitive side, as a thermostat, in that it responds to energy and activity levels within the environment. The combination is a biological gyroscope that balances context and course of action.
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Paul Reed replied on Oct. 26, 2011 @ 17:45 GMT
John
I did mean to put the word 'semantics' in my last post, cos I was not altogether sure whether you agreed or not. I mean, I have to say that it took me ages to try and express this, as opposed to think it. From the point that language is itself embodies these false concepts.
Paul
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T H Ray replied on Oct. 26, 2011 @ 17:55 GMT
John,
In Mach's mechanics, space is a fiction. Mach was a "true" relativist, while Einstein's relativity actually depends on an absolute (the invariance of the speed of light). Einstein wasn't happy, in fact, that his theory bore the name, "relativity," but common usage and history overruled him.
In any case, though, Mach assigned no physical reality to space at all.
Tom
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T H Ray replied on Oct. 26, 2011 @ 18:00 GMT
". . . then how does a variance result from the influence of an observer?"
It doesn't.
"Light is independent of observer, indeed it ceases to exist at the point in time when it makes contact with eyeball."
When a photon is absorbed, by an eyeball or anything else, it exists or doesn't exist to the same extent that it did in flight. The particle is massless.
Tom
(reposted to correct thread)
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Paul Reed replied on Oct. 26, 2011 @ 18:15 GMT
Ray
Your post 26/10 17.47 (in another thread):
“". . . then how does a variance result from the influence of an observer?"
It doesn't.
"Light is independent of observer, indeed it ceases to exist at the point in time when it makes contact with eyeball."
When a photon is absorbed, by an eyeball or anything else, it exists or doesn't exist to the same extent that it did in flight. The particle is massless”.
My reference to ‘light’ was to the ‘image’ being conveyed by the photons, not the reality of photons as such
Paul
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John Merryman replied on Oct. 27, 2011 @ 03:17 GMT
Tom,
I recall your point about Einstein's opinion of the principle of relativity applied to his theory. If, as I contend, time is an effect of motion and not the dimensional basis for it, that only leaves space as the absolute frame.
I understand Mach only considered space, as well as time, a function of measurement, but in the above quote, it is difficult not to see he cannot help but assume space. To what are the stars "fixed?" If he had understood about galaxies, it seems he would have used them, not the stars, as the fixed points of reference.
I don't see space as any form of physicality, aether, quantum fluctuations, etc. Simply as the infinite frame. While theorists might not like this lack of definition, the alternative, space emerging as a measurement from the singularity, has way too many conceptual holes in it. As I've pointed out before, among the many other issues, this ignores the fact that lightspeed is constant to a stable spaceframe, not an expanding one.
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Paul Reed replied on Oct. 27, 2011 @ 06:00 GMT
All
Anyway!! I know John had a go at this, and Tom has said points I agree with (which underpin my reason for asking in the first place). The question is:
When considering the notion that light (as in what is realisable as an optical image of reality) always travels (as in something is conveyed, somehow) at c with respect to observer. Can someone unravel the logic of this, given that either:
a) light travels at the same speed in all circumstances, or
b) light travels at different speeds due to circumstances
If a), then why all this discussion? Light always takes the same amount of time to travel the same distance, irrespective of circumstances. Simple.[Which of course in the vast majority of practical circumstances, it does, but that is not the point].
If b), then how does that variance result from the influence of an observer? Light is independent of the observer. It travels to the observer. Indeed it ceases to exist at the point in time when it makes contact with eyeball.
[The alternative from unravelling the logic being to accept that the notion that light is always c wrt observer, is a fallacy. And to pre-empt a comment which has already been covered-Einstein did not actually stipulate this, but I would rather stick with what is correct, rather than who said what]
Paul
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T H Ray replied on Oct. 27, 2011 @ 10:39 GMT
John,
Space plays no role at all in Mach's physics. To understand how true he was to his mechanics, consider that Mach rejected atomic theory, even though we know now -- and experiments were confirming in his day -- that atoms are made of mostly empty space.
Tom
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T H Ray replied on Oct. 27, 2011 @ 10:48 GMT
Paul,
You wrote: "If a), then why all this discussion? Light always takes the same amount of time to travel the same distance, irrespective of circumstances. Simple.[Which of course in the vast majority of practical circumstances, it does, but that is not the point]."
This claim is as false now as it was the first several times you made it.
"If b), then how does that variance result from the influence of an observer?"
It doesn't.
"Light is independent of the observer. It travels to the observer. Indeed it ceases to exist at the point in time when it makes contact with eyeball."
Don't you realize that this statement is self contradictory? If light is independent of the observer, then it is also independent of the observer's eyeballs. Eyeballs don't change the behavior of light.
Tom
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John Merryman replied on Oct. 27, 2011 @ 10:58 GMT
Tom,
Which just goes to show how hard it is to reject space as fundamental. Whereas with time, when it is eliminated as fundamental, it just comes back as a property of action. It is a measure of change, not the basis for change.
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T H Ray replied on Oct. 27, 2011 @ 11:03 GMT
Paul,
Trying to understand the source of your confusion -- it may be helpful to see that physics never had a problem with light speeds less than the universal constant c, or the speed of light in a vacuum. In fact, experimenters can chemically trap photons. So matter itself is quite well, though not rigorously, characterized as "slow light."
Tom
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T H Ray replied on Oct. 27, 2011 @ 11:17 GMT
John,
It's actually very easy to reject space as fundamental. It's not so easy to reject a continuum of spacetime, that which allows space its curvature, and so introduces the action principle of which you speak. This is all explained by the principles of relativity.
Think of uniform motion as a straight line (special relativity); a curve in that line causes acceleration (change of velocity in the direction of motion). This is how Einstein conceptually arrives at the equivalence of gravity and acceleration.
John, if you would please just study classical mechanics and relativity, all of those exotic consequences with which you take issue would be less mysterious and unthinkable.
Tom
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John Merryman replied on Oct. 27, 2011 @ 15:34 GMT
Tom,
It's quite easy to reject anything as fundamental. the issue is what do you replace it with as an original premise. Basically the discipline of physics has come to the conclusion that only measurements are real. What does that require? Something to measure. So we have points of reference and motions to measure. Relativity takes this one step further and argues motion is built up from points of reference along the fourth dimension. The uniform motion is reduced to a straight line.
So basically time is another dimension of space.
So what is space? Do our measurements create it, or simply define it? We have points(locations, singularities, etc.), lines(one dimension, distances, direction, etc.), planes(two dimensions, area, surface, membranes, etc.) and volume(three dimensions, vacuum, void, etc.).
Does space arise from these concepts, or are these concepts aspects of space?
The argument is that all of reality and space arose from a singularity, a dimensionless point. The original reference. The point from which all measurement and thus reality arises. Yet we can't really say that, because motion has been dismissed as an illusion of the fourth dimension, along which everything that could/can/will ever happen already exists.
So the argument is that our measurements of reality are reality and even one of the primary components being measured, motion, is an illusion because it cannot be measured with deterministic precision, as measurements are static and motion is dynamic and since our theory of time is deterministic, then motion must not be fundamental.
Does it occur to you that maybe sometime in the future, that physics will reject spacetime as not fundamental?
I suppose that in a world where debt is the basis of our common currency and that the more debt we incur, the richer we are, would also be a world where spacetime, with all its wormholes, blocktime, expanding universes, dark energy, inflation, etc, is considered real, but that the dynamic present, motion and space are considered illusions.
Alice in Wonderland has nothing on us.
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T H Ray replied on Oct. 27, 2011 @ 17:42 GMT
John,
It's beyond me why you insist on not reading relativity, and continue to hold forth on what you merely opine about it. I would find that embarrassing.
"Basically the discipline of physics has come to the conclusion that only measurements are real. What does that require? Something to measure. So we have points of reference and motions to measure."
We NEVER measure...
view entire post
John,
It's beyond me why you insist on not reading relativity, and continue to hold forth on what you merely opine about it. I would find that embarrassing.
"Basically the discipline of physics has come to the conclusion that only measurements are real. What does that require? Something to measure. So we have points of reference and motions to measure."
We NEVER measure motion, and neither do we measure relations among points of space. We measure changes in relative position of mass points, and calculate motion from that relation.
"Relativity takes this one step further and argues motion is built up from points of reference along the fourth dimension. The uniform motion is reduced to a straight line."
NO. Motion is measured as changes in the relative position of mass points. Relativity has no privileged rest frame, so your "points of reference" is just more nonsense born of either miscomprehension or incomprehension.
"So basically time is another dimension of space."
NO. Time is physically real only in the continuum of spacetime.
"So what is space?"
Geometry. Coordinates conveniently chosen.
"Do our measurements create it, or simply define it?"
Who cares? It makes no difference to the physics.
"We have points(locations, singularities, etc.), lines(one dimension, distances, direction, etc.), planes(two dimensions, area, surface, membranes, etc.) and volume(three dimensions, vacuum, void, etc.).
Does space arise from these concepts, or are these concepts aspects of space?"
Who cares? It makes no difference to the physics.
"The argument is that all of reality and space arose from a singularity, a dimensionless point."
NO. The argument is that classical physics ends at the singularity. General relativity is known to be (physically) incomplete. Einstein did not claim it to be complete in any way but mathematically.
"The original reference. The point from which all measurement and thus reality arises. Yet we can't really say that, because motion has been dismissed as an illusion of the fourth dimension, along which everything that could/can/will ever happen already exists."
NO. All motion is relative, and no reference frame is privileged.
"So the argument is that our measurements of reality are reality and even one of the primary components being measured, motion, is an illusion because it cannot be measured with deterministic precision, as measurements are static and motion is dynamic and since our theory of time is deterministic, then motion must not be fundamental."
NO. We do not measure "reality" and we do not measure "motion." We measure changes in relative position among mass points.
"Does it occur to you that maybe sometime in the future, that physics will reject spacetime as not fundamental?"
It occurs to me that the universe may be made of cotton candy. What occurs to me is of no consequence to objective physics or rationalist science.
"I suppose that in a world where debt is the basis of our common currency and that the more debt we incur, the richer we are, would also be a world where spacetime, with all its wormholes, blocktime, expanding universes, dark energy, inflation, etc, is considered real, but that the dynamic present, motion and space are considered illusions."
Actually, it is quite possible that the cost of increased energy is increased debt. This is certainly true at the level of quantum vaccum (the more massive the particle, the higher the debt). Which has nothing to do with your confused rhetoric about things you haven't bothered to study.
"Alice in Wonderland has nothing on us."
Speak for yourself.
Tom
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John Merryman replied on Oct. 27, 2011 @ 18:04 GMT
Tom,
I suppose I could offer a detailed rebuttal, but it wouldn't be nearly as effective as your "clarification."
"We NEVER measure motion, and neither do we measure relations among points of space. We measure changes in relative position of mass points, and calculate motion from that relation."
By "calculating that motion," are you saying the motion emerges from the calculation, or that there actually exists a physically real motion which your measurements are approximating?
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T H Ray replied on Oct. 27, 2011 @ 20:02 GMT
John,
"Physically real" implies measurability. Motion is not independent of measured relations, and so does not possess independent, physically real properties. No controversy there.
Tom
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James Putnam replied on Oct. 27, 2011 @ 21:05 GMT
Tom,
Controversy alert!
"Physically real" implies measurability. Motion is not independent of measured relations, and so does not possess independent, physically real properties. No controversy there."
Of course motion is independent of measured relations. It is independent until measurements add their motion to it. Motion is the only reality we know directly. Motion is the only information we receive. Take your measurements in any fashion you wish, but, your result will be information about motion. You will receive a combined form of information about motion that results from the original independently existing motion corrupted by the addition of motion added to by your measurement process. Perhaps I have misunderstood your meaning. Please let me know.
Also, as a side note, Joy has posted his response to Florin. He was probably correct to wait and post it at arxive. I guess that will be determined by discussions that may follow from it. However, I sure would appreciate your reaction being posted here. Thanks.
James
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John Merryman replied on Oct. 28, 2011 @ 01:52 GMT
Tom,
"Motion is not independent of measured relations, and so does not possess independent, physically real properties."
Beliefs cannot be falsified, only patched.
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John Merryman replied on Oct. 28, 2011 @ 02:36 GMT
Tom,
"Einstein did not claim it to be complete in any way but mathematically."
Since it seems necessary to keep repeating arguments that are pushed into the memory hole, epicycles were also mathematically accurate and could have been made extremely accurate, because they are a measure of cosmic observations from our planet. That does not mean there are physically real cosmic gearwheels spinning around the heavens.
It may not matter to the math whether measurements create or define reality, but that is why math is not physics.
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Paul Reed replied on Oct. 28, 2011 @ 06:29 GMT
Tom
Your post 27/10 10.48
You have missed the point I am making. I am not making a “claim”, I am stating a possible outcome, either this or that. In respect of the point about light ceases, I have already explained in another post, and the words in the repeated question in my post of 27/10 06.00 cover this, that I am referring to the ‘conveyed image’.
HOWEVER, and you have given this answer before, I can derive your answer to my question:
-‘light’ does not travel at the same speed in all circumstances
-that speed is not affected by the observer
SO, and of course this is not just asked of you, what is going on? Particularly, how does the concept of ‘always c wrt observer’ work?
Paul
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Paul Reed replied on Oct. 28, 2011 @ 06:48 GMT
James
Your post 27/10 21.05
Correct. Measurement is just our quantification of reality, it is not reality, and cannot affect it. Furthermore, we can only know differences, by comparison, but these are real (absolute) for us, because we live in a limited reality. Within a closed system, what is relative becomes absolute.
Anyway, perhaps when my question has finally been considered, we can use the proper conceptualisation of motion to illuminate my underlying point. Which is: Light (as in what we can realise as an optical image) cannot always travel at c wrt observer.
And in case you are wondering, this goes back through other threads, but trying to maintain a dialogue in this forum can be akin to treading in treacle!!
Paul
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Paul Reed replied on Oct. 28, 2011 @ 07:00 GMT
Tom
Your post 27/10 11.03
Just to add, and clarify. I know this, I agree with you. The point is, once one has said ‘yes/no’ to my questions, then there is a problem for those that maintain a certain stance. [They also attribute this stance to The Theory of Relativity in order to explain it, but it was never the overt position of those that wrote that theory].
However, what usually happens is the thread goes dead, and the same points then resurrect elsewhere.
Paul
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Paul Reed replied on Oct. 28, 2011 @ 08:04 GMT
Pentcho
Your post 28/10 07.34, copied below into the correct thread:
"Paul Reed wrote: "... my underlying point. Which is: Light (as in what we can realise as an optical image) cannot always travel at c wrt observer."
Paul,
This is an epitaph (on the tombstone of modern physics). Do you realise that?
Pentcho Valev pvalev@yahoo.com "
Can you please:
a) explain it
b) explain its relevance to what I am asking
c) address the original question. After all, unlike James and Tom (though anybody is welcome)it was you and Eckard who were incolced in the last exchange which went dead (Tpoic: Neitrino Blacl Magic-Thread Pentcho 10/10 10.17)
Paul
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T H Ray replied on Oct. 28, 2011 @ 10:23 GMT
James,
You wrote: "Motion is the only reality we know directly."
If fact, we do not know motion directly. What we know directly (by objective measurement) are discrete changes in position among mass points. We EXPERIENCE motion directly; however, personal experience is easily shown to be a poor arbiter of fundamental physics.
Tom
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T H Ray replied on Oct. 28, 2011 @ 10:48 GMT
John,
You wrote:
"Tom,
'Motion is not independent of measured relations, and so does not possess independent, physically real properties.'
Beliefs cannot be falsified, only patched."
How ironic of you. You believe that some abstract idea you call "motion" is independent of matter, and then claim science is being obtuse for making motion dependent on physical measure.
You also wrote, "Since it seems necessary to keep repeating arguments that are pushed into the memory hole, epicycles were also mathematically accurate and could have been made extremely accurate, because they are a measure of cosmic observations from our planet. That does not mean there are physically real cosmic gearwheels spinning around the heavens."
And the Ptolemaic astronomers were not so stupid as to believe such a thing. I don't know how many times I have to say it, but the geocentric model is based on the quite reasonable assumption that planetary orbits are circular (they very nearly are). It would have been much harder for Copernicus, et al, to simplify the model if the knowledge accumulated by centuries of observation and mathematical correction were unavailable. Yet you have the hubris to claim that the ancients were "patching" their theory with cosmic gear wheels, just as you claim that modern research is "patching" theory with your straw man imaginings. The basis for your claims is nothing more than personal incredulity, not from any seriouos study of the models and not from a scientific perspective.
"It may not matter to the math whether measurements create or define reality, but that is why math is not physics."
It damn well does matter whether measurements create or define reality. The probabilistic measure of quantum mechanics is observer-created. The continuous measure functions of classical physics are observer entangled. What doesn't matter to physics, is the question of whether mathematics creates or defines reality.
Tom
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John Merryman replied on Oct. 28, 2011 @ 11:22 GMT
Tom,
I didn't say motion is independent of matter. I said it is independent of measure. Which isn't to say that when we measure it, we are not also introducing another factor into the equation and thus are entangled with it.
Copernicus simplified cosmology by correcting a conceptual flaw built into the system, when the conventional solution was to keep adding more epicycles, ie. patches to the Ptolemaic model.
Doesn't it occur to you that when we have a model that keeps getting fixed with ever more fantastical patches, from multiworlds to multiverses, that the problem might be some significant conceptual flaw built into the model?
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T H Ray replied on Oct. 28, 2011 @ 11:34 GMT
"I didn't say motion is independent of matter. I said it is independent of measure. Which isn't to say that when we measure it, we are not also introducing another factor into the equation and thus are entangled with it."
There's no physical meaning in this whatsoever, John. Motion independent of measure HAS to be independent of matter and thus unphysical, because we ONLY measure changes in position among mass points.
Tom
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John Merryman replied on Oct. 28, 2011 @ 16:38 GMT
Tom,
"we ONLY measure changes in position among mass points."
So there is no motion below the scale we can measure? Those mass points don't actually move, they just disappear from one position and reappear in another?
Why no comment on my point about the nature of the Copernican revolution?
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John Merryman replied on Oct. 30, 2011 @ 03:14 GMT
tom,
Yes, quantum mechanics is about the statistical nature of sub-atomic particles, but since they travel at the speed of light, wouldn't it required information traveling faster than light to be able to accurately predict where they strike?
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Paul Reed replied on Oct. 30, 2011 @ 06:54 GMT
John
Not sure I follow that one. Sub-atomic particles 'travel' somehow(ie there is evidence of being at A and then at B, and a duration elapsed). Light is another entity which 'travels' somehow. That also enables us to see (literally)these events. That is, we are comparing frequencies of change. Are these proven to be all the same, ie 'travel' at the same speed? Even so, I do not understand why we would need "information travelling faster". Surely, if one knows their speed and conditions, if any, that influence direction of travel, then one can predict their ETA at a specific spatial point. Albeit within tolerances. Logically, that could include the conclusion we can never know, because their direction of travel is completely random.
Paul
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Paul Reed replied on Oct. 30, 2011 @ 07:05 GMT
All
There is a common view that light (as in what is realisable as an optical image of reality) always travels (as in something is conveyed, somehow) at c with respect to observer. I am concerned about this, because either:
a) light travels at the same speed in all circumstances, or
b) light travels at different speeds due to circumstances
If a), then why all this discussion? Light always takes the same amount of time to travel the same distance, irrespective of circumstances. Simple.[Which of course in the vast majority of practical circumstances, it does, but that is not the point].
If b), then how does that variance result from the influence of an observer? Light is independent of the observer. It travels to the observer. Indeed it ceases to exist at the point in time when it makes contact with eyeball.
Anybody got a view on this apparent conundrum?
Paul
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John Merryman replied on Oct. 30, 2011 @ 11:01 GMT
Paul,
Your question goes to the nature of space and energy and how it relates to the four dimensional math of spacetime, the discussion of which raises lots of other issues, than my specific question to Tom, which is in the context of our long running arguments. Since he is of the shut up and calculate school, my above question as to whether points of measurement disappear and reappear is nonsense. Of course they do. So I'm trying to peel away the layers of measurement to show there is actually something of a physically continuous nature that is only being measured discretely.
A interview you might find interesting,
http://freespace.virgin.net/ch.thompson1/People/CarverMead.h
tm
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Paul Reed replied on Oct. 30, 2011 @ 11:15 GMT
John
Actually, it goes to the fundamental logic of the reality we are a part of. Which is why I keep asking it. As a secondary consideration, it is often put forward as what Einstein said.
And yes I find myself in a somewhat similar dialogue with Georgina elsewhere in the Topic, because, apparently, it is all to do with observation and measurement. Nobody is interested in the actuality. Physics is mathematical sociology.
Paul
I'll have a look at that ref.
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John Merryman replied on Oct. 31, 2011 @ 00:37 GMT
Paul,
Asking physicists to read between the measurements is a lot like asking a computer to read between the digital bits. It does not compute at a very fundamental level.
When this view was first being propagated, it made a good deal of sense, given the natural human tendency to extrapolate on very little information. So insisting on sticking to just the information was a way of enforcing discipline. I suspect though, that were Einstein and company to slip through a wormhole into the present, they would be going through their own church with a big stick, considering the extent to which the fantasizing has slipped through the cracks in the information.
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T H Ray replied on Oct. 31, 2011 @ 10:59 GMT
John,
You wrote, "Yes, quantum mechanics is about the statistical nature of sub-atomic particles, but since they travel at the speed of light, wouldn't it required information traveling faster than light to be able to accurately predict where they strike?"
If a particle (a fermion) has mass, it theoretically moves slower than light speed. Only massless particles (bosons) travel at the speed of light. No two fermions, by the Pauli exclusion principle, can simultaneously occupy the same point, while any number of bosons can occupy the same point.
So your question is meaningless. "Where" a particle is located is independent of "when" it is observed in a nonlocal, i.e., quantum theory. E.g., an electron fouund to be in some particular location could have been anywhere in the universe before observation. That doesn't mean it traveled faster than light -- it means that one couldn't know its location before making a measurement, and further, since making a measurement interferes with the particle's trajectory, we can only determine to arbitrary accuracy either its positon OR its momentum at the time and place that it "strikes," as you put it.
In a fully relativistic theory, however, "where" and "when" are not independent, because spacetime is continuous. That's why there are so many of what you call "patches" (which those who study the subject call "research") in physical theory, as theorists attempt to reconcile the statistics of where (space) to the statistics of when (time) to answer the ultimate question of whether reality is deterministic (classical and continuous) or statistical (quantum and discrete) -- i.e., whether God rolls the dice every time a measurement is made.
Tom
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John Merryman replied on Oct. 31, 2011 @ 11:25 GMT
Tom,
Doesn't that go to the question of whether bosons really are waves when they are traveling and particles, as in specific quanta of energy, when they are absorbed into mass? Such that when they pass through the slits, they really are waves and that the atomic structure of the photon detectors necessarily consists of atomic structure and it's this atomic structure that breaks this energy into quanta.
Possibly, if there were not even slits, there might not even be ripples/waves to the flow of light. The point being that what we observe is very much a function of how the observations are carried out.
"Patches" are what develop when research, ie. observations, don't match theory. What you called "anomalies." Much like more epicycles being added to correct each new perturbation of cosmic action.
"whether God rolls the dice every time a measurement is made."
Making a measurement is a physical process in which input determines output. Since there is no way to fully quantify input prior to the experiment, since that is the point of the experiment, there is no way to fully calculate output, prior to the experiment. Future potential becomes past circumstance.
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John Merryman replied on Oct. 31, 2011 @ 11:32 GMT
Tom,
Not to denigrate the efforts involved, but epicycles did lay the groundwork for many aspects of math, technology and cosmology and required quite a bit of research and study. Copernicus didn't solve the problem by adding more patches, but correcting the problem that created the need for quite so many patches.
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T H Ray replied on Oct. 31, 2011 @ 13:14 GMT
John,
You wrote "Possibly, if there were not even slits, there might not even be ripples/waves to the flow of light. The point being that what we observe is very much a function of how the observations are carried out."
Yes of course. The quantum wave function exists in a superposition of states until measured.
"'Patches' are what develop when research, ie. observations, don't match theory. What you called "anomalies." Much like more epicycles being added to correct each new perturbation of cosmic action."
This obsession of yours, with epicycle corrections, is an exact analog to what we do even today to correct errors in all perturbative phenomena, i.e., continuous functions. What you take to be something wrong with physics, is in actuality how we reconcile measurement and theory. That's what physics IS.
You wrote "Making a measurement is a physical process in which input determines output."
No it isn't. In a classical measurement, space and time intervals are simply coordinate points, not physically real. In a quantum measurement, time is unity and spatial events are nonlocal, not physically real. The idea that quantum mechanics is an observer-created reality hangs on assigning meaning to "the experiment not performed," i.e., an assumed probabilistic reality.
"Since there is no way to fully quantify input prior to the experiment, since that is the point of the experiment, there is no way to fully calculate output, prior to the experiment."
We do it all the time. Just by the simple example of your communicating through your keyboard -- the initial condition is fully defined and the output fully calculated.
"Future potential becomes past circumstance."
Or just as trivially, past circumstance becomes future potential. It doesn't matter.
Tom
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John Merryman replied on Oct. 31, 2011 @ 17:26 GMT
Tom,
I could use more everyday examples that might clarify the process a little better than epicycles. Consider writing computer programs, or frankly any sort of design process. You start out with an idea of what you want, then start building models that might fulfill it. Eventually consensus settles on one over the others. Usually because it is best, but often there is some degree of...
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Tom,
I could use more everyday examples that might clarify the process a little better than epicycles. Consider writing computer programs, or frankly any sort of design process. You start out with an idea of what you want, then start building models that might fulfill it. Eventually consensus settles on one over the others. Usually because it is best, but often there is some degree of circumstance and politics involved. Generally science likes to think it is free of these influences and is usually more free of them than some other areas. Over time though, problems arise with how this model works, so it is constantly being adjusted to new circumstances. This is what you would call, "correct(ing) errors in all perturbative phenomena." This is not always a very neat process though, as sometimes the problems to correct for require adjustments to the model which would disturb other aspects of it, or simply cannot be made to fit. This is what is known as an existential crisis. Does the old model and all it has accomplished, get dropped or broken up, or do the new issues just get papered over as best as possible. Usually there are adherents to both courses of action and a schism forms. Sometimes there is room for both views to co-exist and the situation just reflects increasing complexity. Often these differences will generate conflict until one or the other position prevails. If the conflicts are not fundamental, generally the older model prevails, due to institutional advantages. Occasionally though, the problems with the older model are fundamental and it gets dismissed and then the new models have to compete and grow to fill the space. Nature deals with both sides of this process by having organisms grow to fill their space, then die off, to be replaced by new models, that while they are less informed, are consequently more flexible. Energy expands, while form consolidates.
Since current physics involves some reasonably incompatible ideas, such as relativity, vs. Quantum mechanics, not to mention quite a few patches, from inflation to multiworlds, even string theory, along with its inability to explain quite a few physical constants, the issue does arise as to whether this is just a slow stage in the development of a coherent model, or are there fundamental issues which will require a serious reset, in which there has to be a serious consideration of what we actually know, vs. what we think we know and is there another way to explain that which cannot be dismissed.
" the initial condition is fully defined and the output fully calculated."
On the other hand, if I were to point a telescope toward the sky, there is no way to predict whether I might see a supernova occur, prior to observing it, because the information of its occurrence would have to travel faster than light. There simply is no objective perspective from which all initial conditions can be known. Possibly one might argue the singularity would be this objective position, but since all distinctions are cancelled out, it doesn't seem logical to assume all subsequent form can be deduced within this formlessness. Even inflationary cosmology requires the inflation stage to create differences in a vastly expanded space. So it is only by the occurrence of the event that all input can be fully accounted for.
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John Merryman replied on Nov. 1, 2011 @ 00:48 GMT
Tom,
Presumably the singularity would be a whole lot of bosons, since they would all occupy the same point. So fermions couldn't even come into existence until there is enough space for them to occupy. Now since time and space presumably don't exist at the singularity, since there are no points to measure between, how would we describe this situation of lots of energy, with no projection? Wouldn't the first real measure be temperature, as this energy is starting to move/expand? Considering the background radiation, at 3.7k, is considered residue of this event, it would seem so.
Wouldn't that mean temperature is as, if not more fundamental a measure as either time or space? Why don't we talk about spacetemperature, since the temperature falls in proportion to the extent space expands?
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