michel123456 Posted September 15, 2015 Posted September 15, 2015 (edited) There is a negative sign related with time and you don't address that. I mean, when transforming time into distance the sign is reversed. see discussion in the thread http://www.scienceforums.net/topic/53525-why-negative/ At the end of the thread it is even suggested that: Duration (timelike interval in spacetime) is imaginary, when squared is negative. which has as consequence That makes time perpendicular to space And that Distance for light (lightlike interval in spacetime) is null. Edited September 15, 2015 by michel123456 1
Daedalus Posted September 16, 2015 Author Posted September 16, 2015 Energy is not an object, it is a property of objects. An electron has energy, or an electron-nucleus system has energy. It is not a "thing" unto itself. You can talk about energy transfer, but energy motion. And until you can give an equation describing it, you can't infer motion in QM. (I mean, you can, and obviously do, but it's not rigorous) What's the equation of motion of an electron in an atom? Of its spin orientation? I realize that energy is a property of objects. They only reason why I decided to go ahead and state energy and its various forms was to differentiate between space and the "stuff" that occupies it. I'm perfectly fine with not being able to rigorously define motion in QM. You and I both know that trying to specify an equation for the motion of an electron in an atom is a fool's errand for a novice such as myself or for any other quantum number. Besides, demanding an equation for the motion of something to prove that it moves is no different than demanding the equation for the motion of a car in order to prove that the car can change position. We simply don't need an equation to infer that such things can move or that their structure can change position through space. Furthermore, the concept of the energy contained within electrons changing position through space is studied: http://newscenter.lbl.gov/2010/08/04/electrons-moving/ Through a process called attosecond absorption spectroscopy, researchers were able to time the oscillations between simultaneously produced quantum states of valence electrons with great precision. These oscillations drive electron motion. I might not be able to prove that electrons move by defining an equation that predicts their motion, but I could demonstrate that they are not stationary, which infers motion. With the development of quantum mechanics and experimental findings (such as the two slits diffraction of electrons), it was found that the orbiting electrons around a nucleus could not be fully described as particles, but needed to be explained by the wave-particle duality. In this sense, the electrons have the following properties: Wave-like properties: The electrons do not orbit the nucleus in the sense of a planet orbiting the sun, but instead exist as standing waves. The lowest possible energy an electron can take is therefore analogous to the fundamental frequency of a wave on a string. Higher energy states are then similar to harmonics of the fundamental frequency. The electrons are never in a single point location, although the probability of interacting with the electron at a single point can be found from the wave function of the electron. Particle-like properties: There is always an integer number of electrons orbiting the nucleus. Electrons jump between orbitals in a particle-like fashion. For example, if a single photon strikes the electrons, only a single electron changes states in response to the photon. The electrons retain particle like-properties such as: each wave state has the same electrical charge as the electron particle. Each wave state has a single discrete spin (spin up or spin down). Thus, despite the obvious analogy to planets revolving around the Sun, electrons cannot be described simply as solid particles. In addition, atomic orbitals do not closely resemble a planet's elliptical path in ordinary atoms. A more accurate analogy might be that of a large and often oddly shaped "atmosphere" (the electron), distributed around a relatively tiny planet (the atomic nucleus). Atomic orbitals exactly describe the shape of this "atmosphere" only when a single electron is present in an atom. When more electrons are added to a single atom, the additional electrons tend to more evenly fill in a volume of space around the nucleus so that the resulting collection (sometimes termed the atom’s “electron cloud”[6]) tends toward a generally spherical zone of probability describing where the atom’s electrons will be found. "The electrons do not orbit the nucleus in the sense of a planet orbiting the sun, but instead exist as standing waves." The structure of a standing wave actually changes position through space. "The electrons are never in a single point location". Sounds like they move around to me. I'm sorry about using Wikipedia, but I'm sure if I went down to the physics library at OU, I can get you better references and maybe even a quote from a professor. Of course, I realize this isn't a satisfactory answer to your question of motion in QM, but neither is the answer that there is no motion of any kind of structure at all. There is a negative sign related with time and you don't address that. I mean, when transforming time into distance the sign is reversed. see discussion in the thread http://www.scienceforums.net/topic/53525-why-negative/ Michel123456, when considering space-time, you get time-like, light-like, and space-like intervals. Spacetime intervals in flat space In a Euclidean space, the separation between two points is measured by the distance between the two points. The distance is purely spatial, and is always positive. In spacetime, the displacement four-vector ΔR is given by the space displacement vector Δr and the time difference Δt between the events. The spacetime interval, also called invariant interval, between the two events, s2,%5B15%5D is defined as: [math]s^2=\Delta\,r^2-c^2\Delta t^2[/math] (spacetime interval), where c is the speed of light. The choice of signs for [math]s^2[/math] above follows the space-like convention (−+++).%5B16%5D Spacetime intervals may be classified into three distinct types, based on whether the temporal separation ([math]c^2\Delta t^2[/math]) or the spatial separation ([math]\Delta r^2[/math]) of the two events is greater: time-like, light-like or space-like. Certain types of world lines are called geodesics of the spacetime – straight lines in the case of Minkowski space and their closest equivalent in the curved spacetime of general relativity. In the case of purely time-like paths, geodesics are (locally) the paths of greatest separation (spacetime interval) as measured along the path between two events, whereas in Euclidean space and Riemannian manifolds, geodesics are paths of shortest distance between two points.%5B17%5D%5B18%5D The concept of geodesics becomes central in general relativity, since geodesic motion may be thought of as "pure motion" (inertial motion) in spacetime, that is, free from any external influences. Time-like interval [math]c^2\Delta t^2 >\Delta r^2[/math] [math]s^2 >0[/math] For two events separated by a time-like interval, enough time passes between them that there could be a cause–effect relationship between the two events. For a particle traveling through space at less than the speed of light, any two events which occur to or by the particle must be separated by a time-like interval. Event pairs with time-like separation define a negative spacetime interval () and may be said to occur in each other's future or past. There exists a reference frame such that the two events are observed to occur in the same spatial location, but there is no reference frame in which the two events can occur at the same time. The measure of a time-like spacetime interval is described by the proper time interval, : (proper time interval). The proper time interval would be measured by an observer with a clock traveling between the two events in an inertial reference frame, when the observer's path intersects each event as that event occurs. (The proper time interval defines a real number, since the interior of the square root is positive.) Light-like interval In a light-like interval, the spatial distance between two events is exactly balanced by the time between the two events. The events define a spacetime interval of zero (). Light-like intervals are also known as "null" intervals. Events which occur to or are initiated by a photon along its path (i.e., while traveling at , the speed of light) all have light-like separation. Given one event, all those events which follow at light-like intervals define the propagation of a light cone, and all the events which preceded from a light-like interval define a second (graphically inverted, which is to say "pastward") light cone. Space-like interval When a space-like interval separates two events, not enough time passes between their occurrences for there to exist a causal relationship crossing the spatial distance between the two events at the speed of light or slower. Generally, the events are considered not to occur in each other's future or past. There exists a reference frame such that the two events are observed to occur at the same time, but there is no reference frame in which the two events can occur in the same spatial location. For these space-like event pairs with a positive spacetime interval (), the measurement of space-like separation is the proper distance, : (proper distance). Like the proper time of time-like intervals, the proper distance of space-like spacetime intervals is a real number value. However, the equation are the exact same when considering four-dimensional space. The only difference is the [math]c\,\Delta\,t[/math], which is a distance, is simply specified as the distance light has traveled [math]w_c[/math]. You just rewrite the equation as: [math]s^2 = \Delta\,r^2 - \Delta\,w_c^2[/math] Instead of negative time, you'd get negative spatial displacement in four-dimensional space.
Sensei Posted September 17, 2015 Posted September 17, 2015 (edited) I realize that energy is a property of objects. They only reason why I decided to go ahead and state energy and its various forms was to differentiate between space and the "stuff" that occupies it. It's way more complex than you may think. Say we have gamma photon with energy exceeding 1.022 MeV energy (f>=2fC), once it will collide with stationary atom (stationary in it's own FoR), there is created electron-positron pair. [math]\gamma \rightarrow e^+ + e^-[/math] But we have something like redshift and blueshift Relativistic Doppler effect. [math]f=f_0\sqrt{\frac{1+\frac{v}{c}}{1-\frac{v}{c}}}[/math], blueshift [math]f=f_0\sqrt{\frac{1-\frac{v}{c}}{1+\frac{v}{c}}}[/math], redshift So, if our atom prior collision with photon, is accelerated to significant speed of light, photon that had not enough energy, in "normal" circumstances, will be blueshifted, and in accelerated FoR will have enough energy for pair-production.. ps. It's all about definition of "what is mass", "what is energy", "what is length" and "what is time" (regardless of what swansont is saying it's not definable in numerous of threads). Unlike him, I think they're essential questions in quantum physics. Edited September 17, 2015 by Sensei
Daedalus Posted September 17, 2015 Author Posted September 17, 2015 It's way more complex than you may think. Say we have gamma photon with energy exceeding 1.022 MeV energy (f>=2fC), once it will collide with stationary atom (stationary in it's own FoR), there is created electron-positron pair. [math]\gamma \rightarrow e^+ + e^-[/math] But we have something like redshift and blueshift Relativistic Doppler effect. [math]f=f_0\sqrt{\frac{1+\frac{v}{c}}{1-\frac{v}{c}}}[/math], blueshift [math]f=f_0\sqrt{\frac{1-\frac{v}{c}}{1+\frac{v}{c}}}[/math], redshift So, if our atom prior collision with photon, is accelerated to significant speed of light, photon that had not enough energy, in "normal" circumstances, will be blueshifted, and in accelerated FoR will have enough energy for pair-production.. ps. It's all about definition of "what is mass", "what is energy", "what is length" and "what is time" (regardless of what swansont is saying it's not definable in numerous of threads). Unlike him, I think they're essential questions in quantum physics. I realize those things too. My point is that we don't need to define time as some physical dimension to formulate the laws of physics. Clocks use motion to measure time, and we can replace the time variable [math]t[/math] with measurements of distance no different than I showed in my post.
Mordred Posted September 17, 2015 Posted September 17, 2015 As promised I looked over your model proposal. Aside from the DE, extra dimensions, and dark matter conjectures which you will need to rethink. More on those points later on. There is one key detail that runs counter to observational evidence. " The Big Bang FoR has its origin located at the center of a four dimensional sphere that is expanding." The Cosmological principle states the universe homogeneous and isotropic. The model you presented defines a preferred location. (Big bang origin point ). To see why this is wrong read these two articles. http://www.phinds.com/balloonanalogy/: A thorough write up on the balloon analogy used to describe expansion http://tangentspace.info/docs/horizon.pdf:Inflation and the Cosmological Horizon by Brian Powell. Cosmological measurements agree that there is no center of expansion. A center has a preferred location and direction. Homogeneous means no preferred location, isotropy means no preferred direction. Together they define a uniform energy/mass distribution which is what the formulas of the FLRW metric also defines.
Daedalus Posted September 17, 2015 Author Posted September 17, 2015 As promised I looked over your model proposal. Aside from the DE, extra dimensions, and dark matter conjectures which you will need to rethink. More on those points later on. There is one key detail that runs counter to observational evidence. " The Big Bang FoR has its origin located at the center of a four dimensional sphere that is expanding." The Cosmological principle states the universe homogeneous and isotropic. The model you presented defines a preferred location. (Big bang origin point ). To see why this is wrong read these two articles. http://www.phinds.com/balloonanalogy/: A thorough write up on the balloon analogy used to describe expansion http://tangentspace.info/docs/horizon.pdf:Inflation and the Cosmological Horizon by Brian Powell. Cosmological measurements agree that there is no center of expansion. A center has a preferred location and direction. Homogeneous means no preferred location, isotropy means no preferred direction. Together they define a uniform energy/mass distribution which is what the formulas of the FLRW metric also defines. I'll definitely take a look at those links when I can Mordred. During the week, I don't have much time for fun stuff like this because of work, but I'll definitely check it out this weekend.
Sensei Posted September 17, 2015 Posted September 17, 2015 (edited) Mordred, you think your links are absolute truth, undeniable dogmas. There is needed more humble opinion. Don't reject experimental evidence prior you know it first.. (whatever it is).. f.e. Dark flow https://en.wikipedia.org/wiki/Dark_flow ps. You don't know, what you don't know.. Edited September 17, 2015 by Sensei
Daedalus Posted September 17, 2015 Author Posted September 17, 2015 Mordred, you think your links are absolute truth, undeniable dogmas. There is needed more humble opinion. Well, I haven't retracted my statements. However, I'm willing to look at the evidence Mordred presented. I think that's just as important, if not more so, than trying to come up with some idea. 1
Mordred Posted September 17, 2015 Posted September 17, 2015 (edited) Mordred, you think your links are absolute truth, undeniable dogmas. There is needed more humble opinion. Don't reject experimental evidence prior you know it first.. (whatever it is).. f.e. Dark flow https://en.wikipedia.org/wiki/Dark_flow ps. You don't know, what you don't know.. Sure there may or may not be a CMB dipole dark flow. This is a subject still under considerable debate. Dark flow does not imply a center of the universe. Perhaps you should read up on dark flow. http://arxiv.org/pdf/1411.4180 Keep in mind there is numerous models that use dark flow as evidence of a multi universe evidence. Until the results are conclusive I will continue to answer questions and post what textbooks describe. If one gets too distracted by all the counter models to every theory, well lets just say you can easily be led astray. I've always felt its better to answer questions according to the concordance models. The links I choose to post reflect the textbooks. Currently in Cosmology the concordance models is the FLRW metric. Though LQC is a good competitor. That model also follows the cosmological principle. I've long ago lost track of how many models that never competed significantly to LCDM due to not following the cosmological principle. Are those models still around? In many cases yes. Are they largely considered by the majority of cosmologists as being good models of our universe to observational evidence. No. (Side note, our own peculiar velocity causes a large portion of the CMB dipole.) How much of The detected signal is due to calibration errors to compensate for redshift effects due to our peculiar velocity? The second set of Planck underwent considerable calibration refinements and does not support dark flow according to Planck. Yes I posted a counter argument paper. ( most forums follow the policy, of all answers to posts must be in accordance to the mainstream). Ie textbooks. Here is a quote from Matt Roose "Introduction to Cosmology" on the CMB dipole. "The interpretation today is that not only does the Earth move around the Sun, and the Solar System participates in the rotation of the Galaxy, but also the Galaxy moves relative to our Local Galaxy Group, which in turn is falling towards a centre behind the HydraCentaurus supercluster in the constellation Virgo. From the observation that our motion relative to the CMB is about 365 km s−1, these velocity vectors add up to a peculiar motion of the Galaxy of about 550 km s−1, and a peculiar motion of the Local Group of about 630 km s−1 [5]. Thus the dipole anisotropy seen by the Earth-based observer A in Figure 8.2 tells us that we and the Local Group are part of a larger, gravitationally bound system." Page 216 In further defense of the links I post. "Please note that all posts that are baseless in scientific fact or that are outside of mainstream physics can and will be moved to the Speculations forum. " So I ask you why would I incur infractions, by posting non mainstream answers and articles? Just a side note the above paper discusses Sunyaev-Zeldovich effect which involves the Kompaneets equation http://www.weizmann.ac.il/home/kblum/IPC/tutorial%20notes/TutKfirSZ.pdf Edited September 17, 2015 by Mordred 1
swansont Posted September 17, 2015 Posted September 17, 2015 Furthermore, the concept of the energy contained within electrons changing position through space is studied: http://newscenter.lbl.gov/2010/08/04/electrons-moving/ That's a dynamic system in which they've just ionized an atom, so it's not the same conditions, and you're relying on the press-release wording. I might not be able to prove that electrons move by defining an equation that predicts their motion, but I could demonstrate that they are not stationary, which infers motion. The part that says the electron does not exist at a single point can be written as the electron exists everywhere. If something exists everywhere, how can it move? The larger issue is you can't rely on pop-sci descriptions of QM to understand QM, especially when you interpret it in terms of classical physics. That way is doomed to failure.
Vivec Posted September 17, 2015 Posted September 17, 2015 So let me get this strait. You are implying the impossibility of time travel? Is there any way to simplify the point that you're making? I read through the thread and, while I find myself intrigued, I find it a little difficult to follow. I kind of understand, but what I got (ADHD) was a visual of someone trying to go back to yesterday only to find that yesterday is not the same day as it was then and the instances in space-time have changed. Kind of like what happened to Trunks in Dragon Ball Z. He tried to go back in time to prepare the Z warriors for the arrival of deadly androids and stop the death of Son Goku. What he found was that the timeline he had reached was dramatically different than his own. Goku didn't get sick the same way, there were five unheard of androids and the Z warriors were considerably stronger on top of the fact that the androids weren't evil in the new timeline. It's as if he had only traveled through space, not time, to a universe greatly similar to his own. Now that, along with what I think you're saying, makes sense. But that's what went through MY mind. If you don't care, please restate your point in a different way. It doesn't have to be too much simpler, just different.
Daedalus Posted September 17, 2015 Author Posted September 17, 2015 (edited) That's a dynamic system in which they've just ionized an atom, so it's not the same conditions, and you're relying on the press-release wording. You're right. I should've put more thought into my reply. When I get home from work, I'll try to come up with a better argument relating back to electron clouds. The part that says the electron does not exist at a single point can be written as the electron exists everywhere. If something exists everywhere, how can it move? The larger issue is you can't rely on pop-sci descriptions of QM to understand QM, especially when you interpret it in terms of classical physics. That way is doomed to failure. In your reply, you are still assuming that I'm viewing motion in a classical sense. I could be wrong, but it seems to me that you are cherry picking parts of my argument that falls short or is lacking while ignoring other points that I believe are valid. For instance, I have defined motion as the act of changing position through space. I haven't specified how the change in position occurs. Only that a change in position through space is motion. Given atomic orbitals, we know there is a defined shape for each orbital that represents the probability of detecting an electron at a specific point in space. Furthermore, we know that when electrons become excited, they will jump to different orbitals and then back to their original orbital releasing radiation when they do. Because they change orbitals, regardless of how they do this, the electron is changing position through space, which is motion as I have defined it. With the development of quantum mechanics and experimental findings (such as the two slits diffraction of electrons), it was found that the orbiting electrons around a nucleus could not be fully described as particles, but needed to be explained by the wave-particle duality. In this sense, the electrons have the following properties: Wave-like properties: The electrons do not orbit the nucleus in the sense of a planet orbiting the sun, but instead exist as standing waves. The lowest possible energy an electron can take is therefore analogous to the fundamental frequency of a wave on a string. Higher energy states are then similar to harmonics of the fundamental frequency. The electrons are never in a single point location, although the probability of interacting with the electron at a single point can be found from the wave function of the electron. Particle-like properties:There is always an integer number of electrons orbiting the nucleus. Electrons jump between orbitals in a particle-like fashion. For example, if a single photon strikes the electrons, only a single electron changes states in response to the photon. The electrons retain particle like-properties such as: each wave state has the same electrical charge as the electron particle. Each wave state has a single discrete spin (spin up or spin down). Thus, despite the obvious analogy to planets revolving around the Sun, electrons cannot be described simply as solid particles. In addition, atomic orbitals do not closely resemble a planet's elliptical path in ordinary atoms. A more accurate analogy might be that of a large and often oddly shaped "atmosphere" (the electron), distributed around a relatively tiny planet (the atomic nucleus). Atomic orbitals exactly describe the shape of this "atmosphere" only when a single electron is present in an atom. When more electrons are added to a single atom, the additional electrons tend to more evenly fill in a volume of space around the nucleus so that the resulting collection (sometimes termed the atom’s “electron cloud”%5B6%5D) tends toward a generally spherical zone of probability describing where the atom’s electrons will be found. Even if you say the electron exists everywhere within this region of space, we know that when "stuff" interacts with it, the shape of this electron cloud changes. Again, I've never stated how this motion occurs, but a change in position in space is still required for the "structure" of the electron cloud to change shape. This is motion, and I have clearly stated this. However, like I said, you seem to ignore this and cherry pick only parts of the argument that you know you can dismiss, which I find surprising of you. If you haven't cherry picked things that I have stated, then why not address everything including the standing wave description or how I've stated that something doesn't have to move like a baseball because its structure, e.g. the shape of the atomic orbital, can change position through space. Lunch is over but, when I get home tonight, I will include other references that demonstrate this "motion" of the electron, which is what I intended by referencing the pop-sci article. Edited September 17, 2015 by Daedalus
swansont Posted September 17, 2015 Posted September 17, 2015 In your reply, you are still assuming that I'm viewing motion in a classical sense. I could be wrong, but it seems to me that you are cherry picking parts of my argument that falls short or is lacking while ignoring other points that I believe are valid. For instance, I have defined motion as the act of changing position through space. I haven't specified how the change in position occurs. Only that a change in position through space is motion. Given atomic orbitals, we know there is a defined shape for each orbital that represents the probability of detecting an electron at a specific point in space. Furthermore, we know that when electrons become excited, they will jump to different orbitals and then back to their original orbital releasing radiation when they do. Because they change orbitals, regardless of how they do this, the electron is changing position through space, which is motion as I have defined it. The thing about science is that we try and have precise definitions that everyone uses, so how you define it means a lot less if you are trying to make a physics argument. You don't have a trajectory, and you don't have a momentum for the electron. And it gets worse... Even if you say the electron exists everywhere within this region of space, we know that when "stuff" interacts with it, the shape of this electron cloud changes. Again, I've never stated how this motion occurs, but a change in position in space is still required for the "structure" of the electron cloud to change shape. This is motion, and I have clearly stated this. If that's motion, then you should be able to ascribe a momentum to the electron; it moved from one point to another in a certain interval, meaning there would also be an angular momentum associated with this motion about the nucleus. How does that work, given that they have quantized angular momentum and we know that some states have zero angular momentum? That demands linear motion, and yet the probability distribution of an S-state is a sphere. Doesn't work. However, like I said, you seem to ignore this and cherry pick only parts of the argument that you know you can dismiss, which I find surprising of you. If you haven't cherry picked things that I have stated, then why not address everything including the standing wave description or how I've stated that something doesn't have to move like a baseball because its structure, e.g. the shape of the atomic orbital, can change position through space. As above, I'm not ignoring it, I'm disagreeing with it, and how is it cherry-picking? And why are you surprised at my focusing on one part of an argument? I don't need to dismantle the whole model to show that it's wrong, just one crucial linchpin. Further, parts of a model can be correct, but the whole can be wrong, because of some fundamental error or omission (e.g. the Bohr model. It gets some things right, but the model as a whole is wrong)
Daedalus Posted September 17, 2015 Author Posted September 17, 2015 (edited) The thing about science is that we try and have precise definitions that everyone uses, so how you define it means a lot less if you are trying to make a physics argument. You don't have a trajectory, and you don't have a momentum for the electron. And it gets worse... Granted, I can't describe the motion of an electron, nor can I define a trajectory, or the momentum in a classical sense, but you really can't either. QM doesn't deal with such things. It's mainly concerned with probabilities associated with other physical characteristics that describe the behavior of matter. If that's motion, then you should be able to ascribe a momentum to the electron; it moved from one point to another in a certain interval, meaning there would also be an angular momentum associated with this motion about the nucleus. How does that work, given that they have quantized angular momentum and we know that some states have zero angular momentum? That demands linear motion, and yet the probability distribution of an S-state is a sphere. Doesn't work. Given how we measure properties of electrons, none of that makes any sense. How can one ascribe momentum to the probability of detecting an electron at a point in space? How could we use equations that are derived from observations that rely on such probabilities to even determine motion in a classical sense? As above, I'm not ignoring it, I'm disagreeing with it, and how is it cherry-picking? And why are you surprised at my focusing on one part of an argument? I don't need to dismantle the whole model to show that it's wrong, just one crucial linchpin. Further, parts of a model can be correct, but the whole can be wrong, because of some fundamental error or omission (e.g. the Bohr model. It gets some things right, but the model as a whole is wrong) You haven't really been paying much attention to anything I've said, or at least you are playing devil's advocate. QM came about in this discussion because I made a claim that all clocks use motion to measure the time. You can't make a mechanical clock that doesn't use motion to measure time. However, you and Klaynos introduced QM as it applies to atomic clocks because you state that QM properties of matter can't be described as motion. Of course, you are correct because measurements in QM such as those for atomic orbitals are based on probabilities. However, my argument towards clocks doesn't care about how things move. The only statement I have to defend is that change in a system can only be propagated if "stuff" is allowed to change position through space. If change can occur without "stuff" changing position through space, then my statements about measuring time with motion would be false. So, you keep hounding me to take equations that are based on probabilities to demonstrate that motion in the classical sense occurs in QM because if I can't then you have proven your point, but that's simply not true in relation to my argument at all. The fact that we have to assign a probability to a point in space where an electron might be is all I need to infer motion in QM system such as atomic orbitals. Either you find the electron at the point in space, or you don't. Surely, you can see how this infers motion? Something changed position, and really that is all that matters regarding my claim. Arguing that I have to be able to define classical motion for a set of probabilities is ludicrous, but you continue to assert your argument that if I can't define motion in QM in such way that I must be wrong. I guess we'll have to agree to disagree. It simply doesn't make sense to take billions of measurements of how many times you detected an electron at a point in space and then expect someone to define an equation using those measurements that will describe the motion of an electron in a classical way when all that is needed to support the claim is the fact that "stuff" is changing position through space. Given nothing but space and the stuff that occupies it, the only thing this stuff can do with respect to space is change position through it. So, it should be a logical conclusion that change is propagated by "stuff" changing position through it. Otherwise, how could anything interact with anything else? Edited September 18, 2015 by Daedalus
Sensei Posted September 17, 2015 Posted September 17, 2015 (edited) I can't describe the motion of an electron, nor can I define a trajectory, or the momentum in a classical sense, but you really can't either. Correction: you can't do it for bound-to-atom electrons. But you can do it for free electrons, traveling through vacuum, or through cloud chamber or other particle detector and leaving trace (and slowing down while traveling through medium). The more kinetic energy had particle, the longer trace. Long thin traces are from electrons. Short thick traces are from alpha particles (Helium-4 nucleus) But can you describe where is each atom in every molecule.. ? Either no. For polar molecule it's to some level of precision possible, because they have one region of molecule more positive and opposite more negative. So after flying though external electric field they rotate accordingly to electric field (other electrons or protons gathered on metal electrodes). But for perfect non-polar, it's pointless, as protons and electrons in molecule cancels each other nicely. Edited September 17, 2015 by Sensei
Daedalus Posted September 18, 2015 Author Posted September 18, 2015 (edited) As promised I looked over your model proposal. Aside from the DE, extra dimensions, and dark matter conjectures which you will need to rethink. More on those points later on. There is one key detail that runs counter to observational evidence. " The Big Bang FoR has its origin located at the center of a four dimensional sphere that is expanding." The Cosmological principle states the universe homogeneous and isotropic. The model you presented defines a preferred location. (Big bang origin point ). To see why this is wrong read these two articles. http://www.phinds.com/balloonanalogy/: A thorough write up on the balloon analogy used to describe expansion http://tangentspace.info/docs/horizon.pdf:Inflation and the Cosmological Horizon by Brian Powell. Cosmological measurements agree that there is no center of expansion. A center has a preferred location and direction. Homogeneous means no preferred location, isotropy means no preferred direction. Together they define a uniform energy/mass distribution which is what the formulas of the FLRW metric also defines. Mordred, thank you for the material you provided. I've been reading "Infationary Misconceptions and the Cosmological Horizon" by Brian Powell, and I find it all very intriguing. Of course, I haven't read through all of the papers and links you've provided, but I do want to point out that I have stated previously that my four-dimensional spherical model is at best speculation. After reading back on what I posted in my break down that got this thread going again, I noticed that I didn't put the "speculation" disclaimer in the section, "Temporal Uniformity". Because I don't quite yet know how to use tensors to play with the mathematics of general relativity, it's easier for me to use the "balloon" model to describe how four-dimensional space accounts for our observations but, like I mentioned earlier, I fully realize that it's flawed. Once I can play with Einstein's field equations, I plan on having some fun So, I do apologize to you and everyone else for not clarifying that the 3-sphere shape of the universe in temporal uniformity is just speculation used more like an analogy to describe what we observe. The main goal of temporal uniformity is to define the nature of time in order resolve problems associated with time when dealing with "time travel". The more I began to develop the ideas regarding how we measure time using motion, the more fun it became to speculate about how four-dimensional space can be used to describe thing such as dark matter and the multiverse. However, it's mainly my statements about how we measure time and how change propagates is what I consider to be my argument. So let me get this strait. You are implying the impossibility of time travel? Is there any way to simplify the point that you're making? I read through the thread and, while I find myself intrigued, I find it a little difficult to follow. I kind of understand, but what I got (ADHD) was a visual of someone trying to go back to yesterday only to find that yesterday is not the same day as it was then and the instances in space-time have changed. Kind of like what happened to Trunks in Dragon Ball Z. He tried to go back in time to prepare the Z warriors for the arrival of deadly androids and stop the death of Son Goku. What he found was that the timeline he had reached was dramatically different than his own. Goku didn't get sick the same way, there were five unheard of androids and the Z warriors were considerably stronger on top of the fact that the androids weren't evil in the new timeline. It's as if he had only traveled through space, not time, to a universe greatly similar to his own. Now that, along with what I think you're saying, makes sense. But that's what went through MY mind. If you don't care, please restate your point in a different way. It doesn't have to be too much simpler, just different. Vivec, basically what this all boils down to is how we measure things. In order to measure distance we have to use predefined distances. The same is true for anything else. We use unit masses to measure mass, and we use properties of electromagnetism to measure electric and magnetic properties. So, in order to take a measurement, we have to use the thing we are measuring. When measuring time, we find that we use motion to take the measurement. Of course, all mechanical clocks do this. However, the current discussion is whether or not we can infer motion in atomic clocks. The point is if we measure time using motion and motion is nothing more than a change in position through space, then time doesn't exist as some separate temporal dimension that's intertwined with space. So, "time travel" would be impossible because instead of three-dimensions of space and one of time, there would only by four-dimensions of space where time is a mathematical consequence of "stuff" changing position through space at finite speeds.The evidence I provide for this is based on being able to replace the time variable [math]t[/math] in every equation of physics that uses time with measurements of distance. The reason why we can replace the time variable [math]t[/math] with distance is because change only occurs when "stuff" changes position through space. Figure 2 - The light clock to the left is at rest and the clock to the right is moving relative to the observer's coordinate system. The light clock to the left is stationary in the coordinate system or frame of reference (FoR) of the observer, and the clock to the right is in motion relative to the observer's FoR. For now, let's examine the light clock to the left that is stationary. There are only two ways to use the clock. We can either count the number of times photons have traversed the distance between the two reflective plates and define that measurement as a unit of time, or we can measure the distance the photons traversed between the plates. Both measurements are equally valid and allows us to quantify motion and order events. [math]t = d_c[/math] where [math]t[/math] equals a unit of time and [math]d_c[/math] is the distance traversed by the clock mechanism. Therefore, a unit of time is nothing more than a normalization of a unit of distance. If we choose to use measurements of distance, then we can define speed as the change in distance traversed by energy divided by the change in distance traversed by the clock mechanism. [math]\text{speed} = \frac{\Delta\,d_e}{\Delta\,t} \ \ \text{or} \ \ \frac{\Delta\,d_e}{\Delta\,d_c}[/math] where [math]\Delta\,d_e[/math] is the change in distance traversed by energy when the change in distance traversed by the clock mechanism equals [math]\Delta\,d_c[/math]. If the speed is constant, we could multiply the total distance our clock mechanism has traversed by our newly defined speed, and we can derive the distance the energy traversed through space without having to use units of time. [math]d = \frac{\Delta\,d_e}{\Delta\,d_c} \times d_c[/math] where [math]d[/math] is the calculated distance. Again, this is no different than measuring distance with a ruler. We are simply quantifying the distance traversed by energy in multiples of the unit distance traversed by the clock mechanism. So instead of measuring motion in units of distance per units of time, we are comparing distance to distance, which adheres to the rule that we have to use the phenomena itself to take measurements. The standard equation for motion using only measurements of distance is defined no differently than when we use values of time. So, we can completely rewrite every equation in physics that uses measurements of time to use measurements of distance instead. [math]d = \frac{1}{2} \left(\frac{\Delta\,d_e}{\Delta\,t^2}\right) t^2+\left(\frac{\Delta\,d_e}{\Delta\,t}\right) t + d_0[/math] [math]d = \frac{1}{2} \left(\frac{\Delta\,d_e}{\Delta\,d_c^2}\right) d_c^2+\left(\frac{\Delta\,d_e}{\Delta\,d_c}\right) d_c + d_0[/math] As a result, measurements of time are the only units in physics that can be replaced by units of distance. Such a contradiction is a violation of dimensional analysis, which provides further evidence that when we use time to measure rates of change in physical properties, we are actually using motion to measure the motion of energy changing position. Again, let's recap. There are only two measurements a clock can make; a measure of the number of times the clock mechanism has completed a cycle, or the distance the clock mechanism traversed throughout the cycle. What we experience as the passage of time is the mathematical result of energy being restricted to finite speeds. Since it is mathematically impossible for energy to traverse space with an infinite speed, the passage of time must occur. For any equation in physics, we can replace the time variable [math]t[/math] using measurements of distance. Units of time become normalizations for units of distance and are interchangeable. Edited September 18, 2015 by Daedalus
Mordred Posted September 18, 2015 Posted September 18, 2015 (edited) No problem, I understood that you didn't have the background details in Cosmology applications and I treated your model as a "toy universe". While providing you the tools to increase your knowledge on Cosmology. Little hint, you will find the FLRW metric surprisingly easy to understand compared to GR. Even though The FLRW metric can be derived via the field equations. Out of the numerous textbooks in terms of the FLRW metric, that I've read. Probably the best one specifically covering the FLRW is Barbera Rydens "Introductory to Cosmology" In terms of GR, I like General relativity by Wald. Good intro texts into QM and particle physics are the Introductory books by Griffith. Physical Foundations of Cosmology by Muchanov does one of the better jobs covering nucleosynthesis. Modern Cosmology by Scott Dodelson does a good job on inflation. Introductory to Cosmology by Matt Roose I found good in taking each aspect and simplifying it. I mention the above as outside of formal training the best way to learn is to invest in the right textbooks. If you can't afford textbooks, I always liked dissertations and pedagonal review papers ( lol I'm a bit of a physics textbook collector. I never have enough) Forgot to add Quarks and Leptons is also excellent for modern day particle physics intro, including the Higgs field. As far as inflation goes I've learned a ton in discussions with Brian Powell. Edited September 18, 2015 by Mordred 1
Daedalus Posted September 18, 2015 Author Posted September 18, 2015 (edited) No problem, I understood that you didn't have the background details in Cosmology applications and I treated your model as a "toy universe". While providing you the tools to increase your knowledge on Cosmology. Little hint, you will find the FLRW metric surprisingly easy to understand compared to GR. Even though The FLRW metric can be derived via the field equations. Out of the numerous textbooks in terms of the FLRW metric, that I've read. Probably the best one specifically covering the FLRW is Barbera Rydens "Introductory to Cosmology" In terms of GR, I like General relativity by Wald. Good intro texts into QM and particle physics are the Introductory books by Griffith. Physical Foundations of Cosmology by Muchanov does one of the better jobs covering nucleosynthesis. Modern Cosmology by Scott Dodelson does a good job on inflation. Introductory to Cosmology by Matt Roose I found good in taking each aspect and simplifying it. I mention the above as outside of formal training the best way to learn is to invest in the right textbooks. If you can't afford textbooks, I always liked dissertations and pedagonal review papers Hehehe. I'm the Sr. Software Engineer for an oil and gas company in OKC, OK. So, I can definitely afford text books. Actually, I prefer them, and I have several regarding mathematics and software engineering. I have a few engineering physics books, but I really don't know which advanced books on physics I should get. So, I do appreciate the links and references. I plan on getting as many of those books as I can. I bought a book on tensors, but it's not easy to understand and there aren't many problems to work through. So, I'm still looking for better books on the subject. Edited September 18, 2015 by Daedalus 1
Mordred Posted September 18, 2015 Posted September 18, 2015 (edited) I don't have too many tensor books however one I enjoyed is Bishop, R. L. and Goldberg Tensor Analysis on Manifolds Sean Carroll has a decent article on GR. " Lecture Notes on General Relativity" http://arxiv.org/abs/gr-qc/9712019 I found it well written, Another online resource being the Feyman lectures. http://www.feynmanlectures.caltech.edu/ You May find "Elements on Astrophysics" handy. It's not a textbook, however it has a huge coverage of numerous metrics used in Cosmology and astrophysics. I use this as a handy look up resource. http://www.ifa.hawaii.edu/~kaiser/lectures/elements.pdf (Lol that should give you a few months of study at least) With your software background, you might want to study N Body codes. I bought the tools and algorithm book sometime back, however never got around to actually developing N Body codes. ( note,The book is rather tricky to follow through) http://www.amazon.in/gp/aw/s//ref=mw_dp_a_s?ie=UTF8&i=stripbooks&k=Sverre+J.+Aarseth Refers primarily to Fortran. Though doesn't have any complete codes Off topic but I highly interesting. Here is a brief simulation of our universe. ( an excellent test of current models.) http://www.cfa.harvard.edu/news/2014-10 http://www.illustris-project.org/ Here is the peer review on the simulation. http://arxiv.org/ftp...5/1405.1418.pdf So this begs the question? Although you admit your model has flaws... does the dark matter distribution reflect on your model compared to the simulation you just saw? The video does an excellent job of approximating observational evidence. This is something any good model eventually needs to do. PS numerous models were tested in that simulation. You might want to Google the Navarro Frenk White profile. https://en.m.wikipedia.org/wiki/Navarro%E2%80%93Frenk%E2%80%93White_profile PS.. it's covered in Elements of astrophysics and no I don't expect your practice model to cover the details in the simulation. However it does show an example of needing to expand upon and incorporate various aspects outside of SR. ( on the textbooks I mentioned, Matt Roose does a good job on filament and large structure formation) "The main goal of temporal uniformity is to define the nature of time in order resolve problems associated with time when dealing with "time travel". The more I began to develop the ideas regarding how we measure time using motion, the more fun it became to speculate about how four-dimensional space can be used to describe thing such as dark matter and the multiverse."It is fun, but you need more than SR for dark matter lol.Up to a challenge, write a FAQ on time. Don't include DM or DE Start it as a new topic, this forum could use a good SR descriptive on time. Some of your descriptives are to the point and accurate. I would be curious to see what you come up with. If your up to it you might want to read. Particularly if you want to cover multiverses in regards to time. "Time before time" http://arxiv.org/pdf/physics/0408111 ( PS overall, albeit a few side points your time descriptives are reasonably accurate. Hence I would like to see you help us out with a FAQ.) Hint... define time as a measure of rate of change or duration Not all change involves momentum. Edited September 18, 2015 by Mordred 1
swansont Posted September 18, 2015 Posted September 18, 2015 Granted, I can't describe the motion of an electron, nor can I define a trajectory, or the momentum in a classical sense, but you really can't either. QM doesn't deal with such things. It's mainly concerned with probabilities associated with other physical characteristics that describe the behavior of matter. Given how we measure properties of electrons, none of that makes any sense. How can one ascribe momentum to the probability of detecting an electron at a point in space? How could we use equations that are derived from observations that rely on such probabilities to even determine motion in a classical sense? IOW, motion within these systems is an ill-formed concept. So you can't say anything about motion. You haven't really been paying much attention to anything I've said, or at least you are playing devil's advocate. If that's what you call pointing out a claim that's wrong, then OK. QM came about in this discussion because I made a claim that all clocks use motion to measure the time. You can't make a mechanical clock that doesn't use motion to measure time. However, you and Klaynos introduced QM as it applies to atomic clocks because you state that QM properties of matter can't be described as motion. Of course, you are correct because measurements in QM such as those for atomic orbitals are based on probabilities. However, my argument towards clocks doesn't care about how things move. The only statement I have to defend is that change in a system can only be propagated if "stuff" is allowed to change position through space. If change can occur without "stuff" changing position through space, then my statements about measuring time with motion would be false. So, you keep hounding me to take equations that are based on probabilities to demonstrate that motion in the classical sense occurs in QM because if I can't then you have proven your point, but that's simply not true in relation to my argument at all. The fact that we have to assign a probability to a point in space where an electron might be is all I need to infer motion in QM system such as atomic orbitals. Either you find the electron at the point in space, or you don't. Surely, you can see how this infers motion? I can see how that implies motion to someone who is interpreting effects from the perspective of classical physics. However, the lesson of QM is that these classical concepts don't apply. 1
michel123456 Posted September 18, 2015 Posted September 18, 2015 +1 to everybody for the interesting discussion.
michel123456 Posted September 19, 2015 Posted September 19, 2015 Maybe the disagreement between the OP & Swansont is about the use of the word "motion". If I understand clearly for Swansont "motion" is a phenomenon described by the laws of Newton. Could be called "Newtonian Motion". While the OP describes "motion" as any change of position in space. Maybe should the OP use the word "displacement", or any other better suited instead of "motion".
Daedalus Posted September 20, 2015 Author Posted September 20, 2015 (edited) Maybe the disagreement between the OP & Swansont is about the use of the word "motion". If I understand clearly for Swansont "motion" is a phenomenon described by the laws of Newton. Could be called "Newtonian Motion". While the OP describes "motion" as any change of position in space. Maybe should the OP use the word "displacement", or any other better suited instead of "motion". I don't think displacement is the correct term either because displacement is just a vector with the head at your current location and the tail at the origin. IOW, motion within these systems is an ill-formed concept. So you can't say anything about motion. ... If that's what you call pointing out a claim that's wrong, then OK. ... I can see how that implies motion to someone who is interpreting effects from the perspective of classical physics. However, the lesson of QM is that these classical concepts don't apply. Although we can't define equations for motion dealing with atomic clocks and QM, we can still infer motion even if it is an "ill-formed concept". I agree with swansont that QM doesn't need to define motion in the classical sense. However, given space and "stuff" that fills it, the only thing matter and energy can do with respect to space is change position through it. Without that, then the equations of QM can't even be defined. You still need a metric space and, by defining such space, then matter and energy can only change position through it regardless of how this occurs. So, if such a concept is "ill-formed" when dealing with QM, then I can accept such a statement because logically and mathematically with respect to space the only thing this "stuff" can do is change position through it. Although I do not have a complete understanding of QM as Swansont does, our argument is pretty close to one that Schrodinger and Bohr had in Copenhagen. I absolutely love this passage from Walter Moore's book, Schrodinger Life and Thought. The discussion between Bohr and Schrodinger began at the railway station in Copenhagen and was carried on every day from early morning till late at night. Schrodinger lived at Bohr's house so that even external circumstances allowed scarcely any interruptions of the talks. And although Bohr as a rule was especially kind and considerate in relation with people, he appeared to me now like a relentless fanatic, who was not prepared to concede a single point in his interlocutor or to allow him the slightest lack of precision. It will scarcely be possible to reproduce how passionately the discussion was carried on from both sides. Schrodinger: You surely must understand, Bohr, that the whole idea of quantum jumps leads to nonsense. It is claimed that the electron in a stationary state of an atom first revolves periodically in some sort of an orbit without radiating. There's no explanation given of why it should not radiate; according to Maxwell theory, it must radiate. The electron jumps from this orbit to another one and thereby radiates. Does this transition occur gradually or suddenly? If it occurs gradually, then the electron must gradually change its rotation frequency and its energy. It's not comprehensible how this can give sharp frequencies for spectral lines. If the transition occurs suddenly, in a jump so to speak, then indeed one can get from Einstein's formulation of light quanta the correct vibration frequency of the light, but then one must ask how the electron moves in the jump. Why doesn't it emit a continuous spectrum, as electromagnetic theory would require? And what laws determine its motion in the jump? Well, the whole idea of quantum jumps must simply be nonsense. Bohr: Yes, in what you say, you are completely right. But that doesn't prove that there are no quantum jumps. It only proves that we can't visualize them, that means, that the pictorial concepts we use to describe the events of everyday life and the experiments of the old physics do not suffice to represent the process of a quantum jump. The is not so surprising when one considers that the processes with which we are concerned here cannot be the subject of direct experience... and our concepts do not apply to them. Schrodinger: I don't want to get into a philosophical discussion with you about the formation of concepts... but I should simply like to know what happens in an atom. It's all the same to me in what language you talk about it. If there are electrons in atoms, which are particles, as we have so far supposed, the must also move about in some way. At the moment, it's not important to me to describe this motion exactly; but it must at least be possible to bring out how they behave in a stationary state or in a transition from one state to another. But one sees from the mathematical formalism of wave or quantum mechanics that it gives no rational answer to these questions. As soon, however, as we are ready to change the picture, so as to say that there are no electrons as particles but rather electron waves or matter waves, everything looks different. We no longer wonder about sharp frequencies. The radiation of light becomes as easy to understand as the emission of radio waves by an antenna, and the former unsolvable contradictions disappear. Bohr: No, unfortunately that is not true. The contradictions do not disappear, they are simply shifted to another place... Think of the Plank radiation law. For the derivation of this law, it is essential that the energy of the atom have discrete values and change discontinuously... You can't seriously wish to question the entire foundations of quantum theory. Schrodinger: Naturally I do maintain that all these relations are already completely understood... but I think the application of thermodynamics to the theory of matter waves may eventually lead to a good explanation of Planck's formula... Bohr: No, one cannot hope for that. For we have known for 25 years what the Plank formula means. And also we see the discontinuities, the jumps, quite directly in atomic phenomena, perhaps on a scintillation screen or in a cloud chamber... You can't simple wave away these discontinuous phenomena as though they didn't exist. Schrodinger: If we are still going to have to put up with these damn quantum jumps, I am sorry that I ever had anything to do with quantum theory. Bohr: But the rest of us are very thankful for it - that you have - and your wave mechanics in its mathematical clarity and simplicity is a gigantic progress over the previous form of quantum mechanics. Like Schrodinger, I am arguing that atomic phenomena must change position through space and, although I can't describe how this would work, I also realize that we can't describe QM in the classical sense. However, my argument is not based on how this motion occurs. QM works completely different than the "old physics" because "we see the discontinuities, the jumps, quite directly in atomic phenomena". All I need to defend motion as the act of changing position through space as far as atomic clocks are concerned is the notion that given a metric space, matter and energy can only change position through space. I agree that this idea is "ill defined" with regard to how the equations of QM are derived. However, we do not need to define such classical motion to study the QM affects that arise from it. QM ignores this because we only care how the QM system behaves. This is because we simply cannot observe or derive equations of motion in the classical sense to describe quantum phenomena. However, my argument is not how motion is carried out but, given space, the only thing matter and energy can do with respect to such space is move through it. We don't need to define a trajectory; only recognize that change in a system can only occur when matter and energy changes position through space. Even though a change in position through space is "ill defined" for QM, without it, QM system would not arise. As for swansont, he approaches the argument much like Bohr. We simply can't describe such motions in a classical sense, but the equations derived by Schrodinger means that we don't have to define it in such a way. So, swansont, realizing this, defends his argument that we can't describe QM affects using motion. However, I feel like he is being as adamant as Bohr and ignores that the energy of the atom must change position through space even though the equations of QM do not define such behaviour using this classical concept but, if we redefine motion as simply the act of changing position through space, then such a definition encapsulates both classical and QM. Granted, defining how particles and energy changes position through space is "ill formed" with regard to QM, I feel that we can't dismiss it completely because, if these particles and waves do not change position through space in some way, then change in the QM will not occur. I realize that my argument will still not be satisfactory for swansont but, much like Schrodinger who never reached an agreement with Bohr, I am content with not reaching an agreement with him. Although I cannot describe such motions in regard to QM, I believe I have provided enough evidence to infer motion within QM even though it cannot be described with an equation and is therefore "ill defined". Edited September 20, 2015 by Daedalus
swansont Posted September 21, 2015 Posted September 21, 2015 I can only lead the horse to water. If you want to insist on how things work while admittedly not understanding QM, there's a limit to how much I can do.
OptimisticCynic Posted September 25, 2015 Posted September 25, 2015 O.K. well understood. But NEVER make honest statements about your lack of knowledge. It is intellectual suicide in this Forum. No need to lie, just don't say anything. That is my humble advice. This reminds me of the adage, "Better to remain silent and appear a fool, than to speak and remove all doubt." " There are many more mechanisms that clocks use to measure time, such as oscillations as provided by crystals, but the point is that they are all based on mechanisms that oscillate. Oscillation in itself is motion and, more specifically, it is motion that repeats with a specified frequency. It is because time can only be measured with motion that motion must be inherent in time. " Yes, time is measured with motion. However, it may be more accurate to say that all clocks measure distance traveled. The distinction being that distance is a characteristic of all dimensions and thus no fourth dimension is needed to explain it.
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