Preferred Frame Theory indistinguishable from SR
in [Relativity]
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From: Daryl McCullough on 22 Jul 2010 08:22 Edward Green says... > >On Jul 18, 1:08=A0pm, stevendaryl3...(a)yahoo.com (Daryl McCullough) >wrote: >> >"Think of waves on the surface of water. Here we can describe two >> >entirely different things. Either we may observe how the undulatory >> >surface forming the boundary between water and air alters in the >> >course of time; or else with the help of small floats, for instance we >> >can observe how the position of the separate particles of water alters >> >in the course of time. If the existence of such floats for tracking >> >the motion of the particles of a fluid were a fundamental >> >impossibility in physics if, in fact, nothing else whatever were >> >observable than the shape of the space occupied by the water as it >> >varies in time, we should have no ground for the assumption that water >> >consists of inovable particles. But all the same we could characterise >> >it as a medium." >> >> >I don't know what the translator intended by "inovable". >> >> I think that must be a typo. But I don't see how that passage is >> inconsistent with the geometric view of gravity. We observe gravity >> through the bends in the paths of particles, like we observe waves >> in water through the bobbing of floaters. > >Well, just to be picky, he is saying here that there _are_ no >floaters; whose purpose in this analogy, by the way, is to fix the >rest frame of the water, not to visualize the waves, which are >regarded as being visible anyway. He is saying we are aware of the >existence of the water via the waves in it, though we cannot assign a >rest frame to it. After re-reading the passage, I have to agree with your interpretation. >> But there is an entity >> that exists whether there are particles (or floaters), and it is >> waves in this entity that we are observing. Whether you call that >> entity the "spacetime manifold" or "aether" doesn't seem to make >> much difference. > >Except that the "spacetime manifold" in my view is the sort of God's >eye record of the activities of the 3d stuff that is doing the >undulating. Well, when you are constructing a *theory* of physics, you get to be God, and know everything there is to know. It is only when you try to apply it, to do experiments that compare theory and experiment, are you humbled into realizing that you aren't God. Your theory is about all of spacetime (or all of space, in the 3D-space-evolving-in-time view), but your experiment just tells you something about a tiny little section of space (or spacetime). That's the reality of the scientific method, it seems to me. I don't see how that implies that it is better to formulate your theories in terms of space, or in terms of spacetime. >> EXCEPT thinking of it as a material aether leaves open the possibility >> of further structure at more microscopic level. Maybe at fine enough >> scales, it isn't homogeneous, isotropic, etc. But then the aether would >> be described as matter moving in *something*---some prior geometry, or >> prior space. > >I like the word "prior". It is an old idea of mine that we could find >an explanation of SR (locally) in terms of something logically prior >to space and time (whatever precisely that means). Maybe it's >something like action -- the universe speaks "action". It does pop up >in the integrand of Feynman path integrals, does it not? And makes >some other appealing cameos, like the volume element in phase space >(do I have that right?). What think you? Space and time are after all >merely the observation of certain regularities in "stuff happening", >and SR tells us that there is a family of such regularities. I've >never quite been satisfied with that observation as a postulate, I >feel we can dig deeper, peel one more layer back on the onion. I definitely think that some future union of General Relativity and quantum theory is likely to dispose of, or drastically alter, our concept of spacetime as the arena on which events play themselves out. However, if people object, based on common sense or intuition or whatever, to SR's mingling of space and time, then it seems likely to me that whatever *replaces* spacetime will be even farther removed from our intuitions, and will be even harder to accept emotionally. Or maybe not--maybe SR and GR are only hard to take because they seem tantalizingly close to our intuitive notions of how the world works, but is just different enough to be irritating. -- Daryl McCullough Ithaca, NY
From: PD on 22 Jul 2010 10:35 On Jul 22, 7:09 am, kenseto <kens...(a)erinet.com> wrote: > On Jul 21, 6:49 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Jul 21, 5:32 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Jul 20, 10:38 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Jul 19, 11:07 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > On Jul 19, 6:34 pm, colp <c...(a)solder.ath.cx> wrote: > > > > > > > On Jul 20, 4:40 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Jul 18, 12:49 am, colp <c...(a)solder.ath.cx> wrote: > > > > > > > > > On Jul 18, 3:53 pm, Paul Stowe <theaether...(a)gmail.com> wrote: > > > > > > > > > > On Jul 17, 5:54 pm, colp <c...(a)solder.ath.cx> wrote: > > > > > > > > > > > On Jul 18, 4:29 am, PaulStowe<theaether...(a)gmail.com> wrote: > > > > > > > > > > > > On Jul 16, 11:39 pm, colp <c...(a)solder.ath.cx> wrote: > > > > > > > > > > > > > On Jul 17, 2:07 pm, PaulStowe<theaether...(a)gmail.com> wrote: > > > > > > > > > > > > > > Just look at the aspects of kinetic theory which underpins ALL! fluid > > > > > > > > > > > > > theory. There is no concept of absolutes there.. > > > > > > > > > > > > > Nope. For example, take two molecules, each with mass m, and separated > > > > > > > > > > > > by distance d. Give the molecules velocities such that they will > > > > > > > > > > > > approach each others center of mass and collide at time t. The > > > > > > > > > > > > calculated energy of the collision will depend on how you measure your > > > > > > > > > > > > velocities. > > > > > > > > > > > > > For either molecule, the relative velocity of the other molecule will > > > > > > > > > > > > be d/t or -d/t. > > > > > > > > > > > > The calculated energy of collision is 1/2 mv^2 = 1/2 m.d^2/t^2, since > > > > > > > > > > > > one molecule is deemed to be stationary. > > > > > > > > > > > > > If, instead, we say that each molecule is moving toward a stationary > > > > > > > > > > > > collision point, then v = d/2t or -d/2t > > > > > > > > > > > > The calculated energy of collision is now 2 * 1/2 mv^2 = m.d^2/4t^2 = > > > > > > > > > > > > 1/2 m.d^2/2t^2 > > > > > > > > > > > > > The two calculations disagree by a factor of two. > > > > > > > > > > > > So? What's your point. > > > > > > > > > > > That the concept of absolute motion is inherent to kinetic theory. > > > > > > > > > > > > Instead of two molecules use you and the > > > > > > > > > > > Earth... From your perspective it's the Earth is hurling towards you > > > > > > > > > > > with a momentum of Mv and you're motionless. OTOH, from the Earth > > > > > > > > > > > perspective it is motionless and you are hurling towards it at mv... > > > > > > > > > > > You have addressed the issue of momentum, not kinetic energy. > > > > > > > > > > You have GOT to be kidding? > > > > > > > > > Not at all. You said: > > > > > > > > > "Just look at the aspects of kinetic theory which underpins ALL! fluid > > > > > > > > theory. There is no concept of absolutes there." > > > > > > > > > The gas laws are part of fluid theory, and one of the gas laws > > > > > > > > describes pressure in terms of average kinetic energy. The calculation > > > > > > > > of kinetic energy depends on how you measure velocity; i.e. the > > > > > > > > velocity relative to a co-ordinate system which is deemed to be > > > > > > > > absolute. > > > > > > > > Nonsense. It is velocity relative to the center of mass of the fluid. > > > > > > > You are contracting Paul, who said: "Just look at the aspects of > > > > > > kinetic theory which underpins ALL! fluid theory. There is no concept > > > > > > of absolutes there." > > > > > > If everything were truly relative two synchronized clocks would always > > > > > be synchronized when in the same state. > > > > > What? What on earth makes you say that? > > > > If everything were truly relative whenever and where ever the two > > > previously synchronized clocks were placed together they would be > > > synchronized. > > > I've already asked you what on earth makes you say that. I didn't ask > > you to repeat it, as though the statement is its own reason. > > > > Everything is with respect to the dark matter. Atomic clocks tick > > > based on the dark matter pressure in which they exist. If the twin in > > > the space ship is moving fast enough the pressure exerted by the > > > displaced dark matter towards and throughout the spaceship, including > > > throughout the atomic clock, will cause the atomic clock on the > > > spaceship to tick slower than the clock on the Earth. If on the return > > > journey the twin in the space ship once again moves fast enough > > > through the dark matter as to have greater dark matter pressure > > > exerted on the atomic clock in the spaceship than on the clock on the > > > Earth the twin in the space ship's clock will have ticked slower than > > > the clock which remained on the Earth. > > > > If the twin travels away from the Earth at such a great speed as to > > > have their clock tick slower than the clock on the Earth but on the > > > return trip slow down enough that the pressure exerted by the > > > displaced dark matter on the clock on the spaceship is less than the > > > pressure exerted on the clock on the Earth the atomic clock on the > > > spaceship will tick faster than the clock on the Earth. > > > > The rate at which the atomic clocks tick is determined by the dark > > > matter pressure in which they exist. > > > The motion with respect to the aether has nothing to do with the > > desynchronization of the clocks. > > Sure it has....absolute motion determines the rate of a clock. Clocks > in relative motion are in different states of absolute > motion....that's why they are desynchronized when they reunited. Well, that's what YOU say. But as I told Mike Cavedon, this is in conflict with experiment. > > Ken Seto > > You may want to look at the > > > > > experimental tests that have been done, which would rule that out > > completely. Nice babble, though.- Hide quoted text - > > > - Show quoted text -- Hide quoted text - > > > - Show quoted text -- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text -
From: Paul Stowe on 22 Jul 2010 20:49 On Jul 21, 8:46 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Jul 21, 9:32 pm, Paul Stowe <theaether...(a)gmail.com> wrote: > > > On Jul 21, 6:40 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Jul 20, 7:21 pm, PaulStowe<theaether...(a)gmail.com> wrote: > > > {Snip...} > > > > > > > You are contracting Paul, who said: "Just look at the aspects of > > > > > > kinetic theory which underpins ALL! fluid theory. There is no concept > > > > > > of absolutes there." > > > > > > Read what I just said. The center of mass of the fluid is in no way an > > > > > absolute frame. > > > > > Where is the 'center of mass' for the pacific ocean??? > > > > This is relatively straightforward to calculate. Why would you think > > > it's difficult? > > > In general R_cms = int[R*rho*dv]/int[rho*dv], where R_cms and R are > > > vectors, R is the location of a volume element dv weighted by mass > > > density rho (rho(R)). > > > The momentum of any of the elements doesn't enter into it. Can you see > > > why? > > > > > I think what > > > > you really wanted to say is the frame where the local sum of the > > > > population vector momenta is zero. > > > > I think that's equivalent. > > > > > But, note what I said kinetic > > > > theory 'which underpins' fluid mechanics. At the scales small enough > > > > where kinetic theory is necessary... But, either way, there is no > > > > physical preference for any imagined coordinate system, aka, reference > > > > frame. > > > > That's not quite right. There's the presumption that (1/2)m(v_rms)_x^2 > > > = 1/2)m(v_rms)_y^2 = 1/2)m(v_rms)_z^2. This won't be true where there > > > is a general drift from left to right of the molecules. > > > Then Grad V != 0... With Grad V you have a non-inertial situation, > > but even then, one can 'localized' their volume of interest to a small > > enough region such that the Gradient asymptotically vanishes. > > No, it does not imply that. Consider the asymptotic case where all the > particles are moving in the +x direction, so that v_x = c, v_y = 0, > v_z = 0. Here grad V = 0. But then we're not talking about kinetic theory or standard fluid mechanics. That's totally coherent flow. IFAIKT that's a forced, artifical situation never found in nature. > > Paul Stowe >
From: mathematician on 23 Jul 2010 04:55 On Jun 26, 7:41 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: > Daryl McCullough wrote: > > There is a preferred frame, F, and there is an associated > > coordinate system such that > > > 1. Light travels in straight lines at speed c, as measured in F's > > coordinate system. > > 2. An ideal clocks in motion relative to F has an elapsed time > > given by dT/dt = square-root(1-(v/c)^2), where t is the time > > coordinate of F's coordinate system, and v is the velocity of > > the clock, as measured in F's coordinate system, and T is the > > elapsed time on the clock. > > 3. An ideal meterstick in motion, with the stick aligned in the > > direction of its motion, will have a length given by > > L = square-root(1-(v/c)^2). > > > I would think that anybody could see that rules 1-3 are consistent. > > You cannot deduce a contradiction from these rules. Note that the > > contradiction that so many anti-relativists think that they have > > found in SR, namely, mutual time dilation, is not present in these > > rules, because these rules only mention time dilation with respect > > to a specific, preferred frame. So there is no possibility of deriving > > a "twin paradox" that is a logical contradiction. Right? > > > Well, all the weirdness of SR, including mutual time dilation and > > the relativity of simultaneity *follows* logically from principles > > 1-3! You can prove that if 1-3 are true in the preferred coordinate > > system, then they are *also* true as measured in any coordinate system > > that is related to the preferred coordinate system through the > > Lorentz transforms. > > Yes. This is just one of the theories that are equivalent to SR (i.e. they are > experimentally indistinguishable from SR). This is one way of deriving the > equations of LET (Lorentz Ether Theory). Lorentz used a completely different > method in his 1904 paper. > > There is a much larger class of theories equivalent to SR, consisting of all > theories in which these two criteria apply: > a) the round-trip speed of light is isotropically c in any inertial > frame > and > b) the one-way speed of light is isotropically c in one frame > > Note that (a) is solidly established experimentally, and (b) is basically what > it means to have an aether frame, or any sort of "preferred" frame. > > If you work out the details, you find that all of these theories > have transforms between inertial frames that differ from the > Lorentz transform only in the way coordinate clocks are > synchronized in inertial frames. Note that except for SR and > LET, the synchronization method is ad hoc and artificial. > > In all of these theories except SR and LET, slow clock transport relative to a > moving inertial frame CANNOT be used to synchronize the coordinate clocks of the > frame. And the difference is PRECISELY what it takes to make experiments and > observations be identical to those of SR and LET. > > In all of these theories other than SR (which is the only member of this class > without a preferred frame), there is no possible experiment that can determine > which frame is the preferred frame. That is, no matter which frame you > arbitrarily select to be the "ether frame", the predictions for any experiments > or observations are unchanged. IOW: (b) can be applied to any inertial frame. > Only in SR does (b) apply to all inertial frames simultaneously. > > NOTE: the modern interpretation of this is that it is all > irrelevant. That's because these different "theories" merely > apply different coordinates to the underlying space-time > manifold, and use different transforms among them. Yes, except > for SR and LET those coordinates are pretty unusual.... The > uniqueness of SR is precisely that (b) applies to all frames. > SR is also the only theory that includes the PoR. > > I posted a much longer series of three articles on this 'way back in 1999 --http://groups.google.com/group/sci.physics.relativity/msg/15ceaad17be... > > Tom Roberts You said above that there is no possible experiment that can determine which frame is the preferred frame. Could you Tom answer the following question: Q1. If we use finite long pseudosphere as 2+1 dim. model of the Universe (one space dimension is shrunken away from the full 3+1 dim. model, picture of this pseudosphere is in my profile page). Time dimension is the symmetry axis of the pseudosphere and it starts from the bottom of the finite long pseudosphere("bottom of the bag"). Would this structure form the preferred frame which is unobservable? Hannu
From: Androcles on 23 Jul 2010 05:10
"mathematician" <haporopu(a)luukku.com> wrote in message news:829e903d-1810-4feb-842c-b071551fb6a3(a)u26g2000yqu.googlegroups.com... You said above that there is no possible experiment that can determine which frame is the preferred frame. Could you Tom answer the following question: Q1. If we use finite long pseudosphere as 2+1 dim. model of the Universe (one space dimension is shrunken away from the full 3+1 dim. model, picture of this pseudosphere is in my profile page). Time dimension is the symmetry axis of the pseudosphere and it starts from the bottom of the finite long pseudosphere("bottom of the bag"). Would this structure form the preferred frame which is unobservable? Hannu =========================================== The quasi-avatar of the pseudostructure would be a virtual form of the prophecy commonly applied to the hole at the top of the infinite bag under the rope and lasso theory of finite nooses. |