Fourier wrote: » If this refers to discussions with Morbert I think he took your "motion" to mean velocity. He was just trying to disambiguate the term and made a guess.
Fourier wrote: » They have absolute velocity not relative to anything.
Fourier wrote: » I'm just explaining Newtonian-Galilean physics to make it clear how it advanced over previous notions so you can see the progression of ideas. It's not meant to be a counterpoint to anything you said.
Fourier wrote: » No absolutely not.
Fourier wrote: » The issue was one of confusion since you weren't being precise.
Fourier wrote: » I said a few times the acceleration was absolute but the velocity wasn't. From your posts it was hard to tell if by motion you meant velocity or something more general. You then introduced further confusion (reference frames are artefacts, absolute velocity is a contradiction in terms).
Fourier wrote: » My taking of "motion" to mean velocity is exactly what happened with Morbert, since from our perspective if you meant motion in general it wouldn't even be worth pointing out. Since you were presenting it as contrary to usual physics the natural assumption is that by motion mean you mean velocity. Confusing two people because you try to discuss subjects without ever bothering to learn them and their terminology and then describing that as them confusingly "having an issue" is lazy.
Fourier wrote: » "I will constantly argue against scientific theories and never learn them. Please recognise my own imprecisions as quickly as possible while educating me for free. Any misunderstandings resulting from my odd stance are issues on your end"
OK, so this is contrary to discussions I have had previously on here
If there are theories that define absolute velocity in another way i.e. not relative to something else, then this would not be a contradiction in terms.
There is some confusion here because I never stated that it was.
In presentist interpretations of relativity, wouldn't simultaneity be absolute
I'm not sure why my example caused such an issue though
Fourier wrote: » Yes but physics divides motion into several different aspects and makes distinct claims about each aspect. Thus in just saying "motion" you are eliding all these differences and getting confused as to what physics is specifically saying. This is what's leading you down this rabbit hole as you seem to believe physics says there is no such thing as absolute motion, where as current physical theories say no such thing. They say there is no absolute velocity.
Fourier wrote: » Thus if we take the motion of some body described by some function x(t) then knowledge of each of the derivatives of this function determine the function. Each derivative has been given a name: First: Velocity Second: Acceleration Third: Jerk Fourth: Jounce etc Physics makes different claims about each. It says velocity has no absolute meaning. The rest do. It says fundamental Forces only directly couple to acceleration Recoil effects are proportional to Jerk Physical stress limits are related to Jerk and Jounce...etc
Fourier wrote: » Because we are dealing with a precise science, one has to deal with precise terms. You think you are being more "fundamental", you are actually just being more vague. No theory says motion in your vague sense is relative. Every derivative above velocity has an absolute sense. Relativity concerns velocity alone.
Fourier wrote: » For the fourth time now. It is not a contradiction in terms because you can construct models in which absolute velocity exists and is well defined. I have given you their name. They are bundle models of Aristotelian physics. Please stop constantly repeating this, I have dealt with it four times now
roosh wrote: » The contradiction in terms is in the definition of something absolute as being relative to something. To define absolute velocity as velocity relative to an absolute reference frame is to define absolute velocity as relative velocity.
Fourier wrote: » That's not what these models do though nor is it what I am discussing. They just have absolute motion.
roosh wrote: » Not absolute velocity then?
Fourier wrote: » "Motion" is a vague pre-physical term. The models have absolute velocity.
Fourier wrote: » The point of physical models is that we have ruled out this model experimentally. Absolute velocity is not a part of our world. This was one of the advances of Newtonian-Galilean physics over previous ideas.
Fourier wrote: » Newtonian-Galilean physics said velocity was relative but space and time were absolutely distinguished and simultaneity was absolute. This is where Relativity disagreed. Thus modern theories say velocity and simultaneity are relative. No theory however has said that motion in general is not absolute.
Fourier wrote: » No it's that you never take the time to actually learn the theories or the relevant terminology and thus have a massively incorrect notion of what is being said. I've counted at least eight physicists you've referenced in discussions I've seen where you've fundamentally misunderstood what they were saying since you don't the meaning of the precise words they use.
The idea that you or I can move our hands or our bodies doesn't seem that vague or pre-physical.
It is the notion of absolute velocity which I'm suggesting is a contradiction in terms because it seeks to define absolute velocity as velocity relative to something - that would be relative velocity
It's just that the reasoning that's usually given doesn't seem to address certain very basic facts
Fourier wrote: » "Motion" is a vague pre-physical term.
Fourier wrote: » The models have absolute velocity. From now on I'd ask you to only use velocity and acceleration to clearly distinguish which you mean when you say "motion".
Fourier wrote: » Has to accelerate. Try phrasing all of this using only physical terms not everyday ones.
Fourier wrote: » One of us has to accelerate. And since acceleration is an absolute notion every frame would agree that there is some change in our relative velocities. However this is not absolute velocity, but absolute acceleration.
Fourier wrote: » My point is that all your ideas have the same format: (a) Never learn the actual theories (b) Never use precise language, but a vague mix of everyday and philosophical language (c) Try to conclude old intuitive notions that have not been part of physics for over 400 years are still true
Let's say that you and I are standing face to face, at rest relative to each other. What would be required for relative motion to occur between us? [inert joke here]. It would take for one of us to move. As soon as one of us moves, we are both moving relative to each other. But one of us has to move
I'm familiar with the idea that our current theories say there is no such thing as absolute motion but my reasoning makes me inclined to believe that there must be.
Fourier wrote: » But they're not mathematical artefacts. As I've said this thing of just repeating your own convictions endlessly is tiring. Get a basic book on college physics and you'll see how they are a mathematical model of a physical set up. This is something that's come up a few times and where your lack of knowledge of the mathematics means you don't really understand what the mathematics is doing in a physical theory. Saying "a reference frame is a mathematical artefact" is like reading a book about plants and saying that "ecosystem is a linguistic artefact". Mathematics is just the language in which you speak about physics.
Fourier wrote: » You've never shown how one does this though and we know from QFT that nothing will allow you to do this.
Fourier wrote: » But we already know this. We know what you are trying to establish doesn't exist. If you were simply interested in what we could conclude you'd just learn the current theories. Why try again and again to see if you are able to reintroduce 400 year old notions? There's no reason.
roosh wrote: » In both frames they are moving relative to each other, and in their respective frames each is at rest relative to themselves or their "frame". But without one of them moving, in an absolute sense, there would be no relative motion between them - they would remain static relative to each other.
This appears to go back to the initial issue of reference frames and their being mathematical artefacts
A point that might be worth reiterating is not that it can be demonstrated that one of the trains is absolutely in motion, it seems to be the case that it cannot, but rather we can deduce that one of them must be and thereby conclude that there is absolute motion.
On a basic level, I'm just interested in what conclusions we can draw about the world we live in.
Quantum Erasure wrote: » Maybe it's just a misunderstanding of the term 'absolute'. Is motion occurring? Absolutely. Is it absolute? No.
Fourier wrote: » It's not as there are well-defined theories with absolute velocity. They're experimentally wrong, but the notion isn't a contradiction in terms. I've said this a few times now, it's not necessarily a relational property. It turned out to be, but there are self-consistency models where it is not. If I'm taking the time to answer and explain can you please not repeat this habit of just constantly claiming something is true when I have described to you literal proofs that something is wrong. I said above that Aristotelian bundle models have absolute motion. It's a completely well defined notion since these models exist, thus it is just pointless to keep saying "absolute velocity is a contradiction in terms". What is "absolute motion" distinct from absolute velocity? To my mind absolute motion means you can absolutely, i.e. in all frames, determine they are in motion which means you can determine at least that they have non-zero absolute velocity. I don't understand what motion without velocity is here? Surely if you are undergoing absolute motion then you are moving with respect to the absolute time and absolute space and thus have a rate of change of absolute space with respect to absolute time and thus have an absolute velocity.
Fourier wrote: » Regardless nothing you have presented shows one train is absolutely in motion since there's a frame where train A is stopped and B is moving and another where B is stopped and A is moving. There doesn't seem to be any absolute motion here.
Fourier wrote: » I also don't really understand what this interest in absolute motion is. It's not been part of physics for over 400 years and it has no evidence. It's like constantly trying to find evidence for the primal elements of Greek theology.
roosh wrote: » I'm not suggesting the idea of absolute velocity though. To my mind, velocity must always be relative to something. That would, again to my mind, make the idea of absolute velocity a contradiction in terms.
As mentioned above, I'm not suggesting the idea of an absolute velocity. I think such a concept would be a contradiction in terms bcos velocity is necessarily a relational property.
roosh wrote: » Even if we cannot determine which train is absolutely in motion, to my mind, we can deduce that [at least] one of them must be. It's not a question of velocity because it would be true for any relative velocity. It is more a question of which train is actually moving or which one is doing the moving.
Goosius wrote: » Ok no problem. Since the relevant wiki page ("Objective Collapse") today contains no reference to them being "ruled out", since the page actually states that the number of experiments is growing, and since I have seen a few recent interviews of scientists who support this line of investigation, then we will disagree. I won't be posting any more replies on that topic.
Fourier wrote: » Objective Collapse theories have been ruled out experimentally. Even for non-rel QM their parameters have been pushed into fine tuned regions and we have no-go theorems showing they won't work for relativistic theories like quantum field theory.
Fourier wrote: » You can't. Relativity has no notion of absolute velocity, it's a concept that doesn't even make sense in its model of spacetime.
Fourier wrote: » Yes but the "moving" here is acceleration. Somebody has to accelerate for them to go from relative rest to relative motion. And acceleration is absolute. The velocities however are not. You're analysing a change in velocities, i.e. an acceleration. This is never going to suggest absolute velocities in any sense. This just seems to be a confusion about how relativity works combined with not properly separating the intuitive "move" into the more precise and separate concepts of "velocity" and "acceleration".
we could potentially deduce it from relativity theory
roosh wrote: » Essentially, my reasoning is that if X and Y are at rest relative to each other. For relative motion to occur between them, [at least] one of them has to move. If neither of them moves then there would be no relative motion. Note that, when one of them moves, both move relative to each other.
Fourier wrote: » Of course, I never said otherwise. The point is that there are theories where absolute motion is physically different from relative motion and this difference can be measured. The Free Choice aspect of QM doesn't convert QM into one of these theories thus there is no physical absolute motion.
There would still be relative motion in a world where absolute motion exists
Fourier wrote: » Not really. There are physical theories were there is absolute motion that can easily be measured. Our world isn't described by them though. However the notion of measuring absolute motion isn't a contradiction in terms due to such models, e.g. Aristotelian spacetime modelled using fiber bundles.
roosh wrote: » Measurement by its very nature is a relative process, so the idea that we might measure absolute motion would represent a contradiction in terms
Fourier wrote: » We could conclude that the ship had changed velocity from x to y, but what those velocities were would depend on the reference frame. Thus the acceleration is absolute but not the velocities.
roosh wrote: » If the two bodies are at rest relative to each other, then they suddenly start moving relative to each other, because one of the captains freely chooses to start their engine, would this not lead us to conclude that [at least] one of the ships must have absolutely moved? We can't determine which one it is, but would we not conclude that one of them must have?
Fourier wrote: » The point would be that if the motion was absolute there would be some measurable physical effect distinguishing true absolute "at rest" from mere coordinate "at rest".
Fourier wrote: » Reference frames can be modelled mathematically, but there not just mathematical constructs. You've made this point a few times as if certain things are just mathematics. The magnetic field for example is both a physical entity and is modelled mathematically with a two-form. Same with reference frames they have a physical nature which we then model with mathematics. The mathematics isn't just hanging free with no physical relevance.
Fourier wrote: » Have you read a proper account of what a reference frame is operationally?
roosh wrote: » Wouldn't the same would be true though, if absolute motion did exist; there would always be a co-ordinate "rest frame" for a body in absolute motion?
roosh wrote: » In nature though, objects don't move relative to reference frames bcos reference frames are mathematical artefacts. If absolute motion exists it wouldn't be motion relative to a mathematical reference frame. Wouldn't the same would be true though, if absolute motion did exist; there would always be a co-ordinate "rest frame" for a body in absolute motion?
Fourier wrote: » Relative to that frame.
Goosius wrote: » Maybe I wasn't clear enough. I'm talking about a breakdown of the wave function as caused by the interaction of one particle with the large mass of the measurement device. (i.e. the disturbance of the particle by the device). This interpretation is described in wiki "/wiki/Objective-collapse_theory", and it is certainly not outdated. The wiki is explicit is noting that it is a growing area of research. QUOTE: "there is a growing number of experiments searching for spontaneous collapse effects."
Thus the assertion that quantum particles do not possess pre-existing properties prior to measurement, is most certainly not something that we "know"
