A puzzle for the SRians
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From: artful on 27 Jul 2010 21:43 On Jul 28, 4:35 am, Hayek <haye...(a)nospam.xs4all.nl> wrote: > Daryl McCullough wrote: > > Hayek says... > > >> In the latest Now, every object has a velocity, > >> setting direction and speed. > > > What does "velocity" mean, if not the derivative of > > position with respect to time? > > It is like deprogramming a hare khrishna or something. :-) > > Imagine a three dimensional space. Just three dimensions. > > Now imagine an object in it. > > Now let this object move , and normalize its speed 1. > > When a second object covers twice the ground as the > first then say it has speed 2. > > The position of the objects is called the Now. > > There is no past, no future, just the two objects and > their changing positions. > > No need to define time or have a time dimension. How can an object move (or any change occur) if there is no time? ANSWER: It can't. Once philosophical definition of time is "that which allows things to change".
From: Hayek on 28 Jul 2010 04:40 Daryl McCullough wrote: > Hayek says... > >> Imagine a three dimensional space. Just three dimensions. >> >> Now imagine an object in it. >> >> Now let this object move , and normalize its speed 1. > > What does "move" mean, if you don't have a notion of > time? Just change in position. And the rate of change in position does not have to rely on time, it can exist on its own. > > I know what *I* mean by saying "the object has moved". > It means that the object at one time is at a different > location than it was at an earlier time. That is a convenience approach for you brain. You remember the object in a, and it is now in b. There is only one object, and it is no longer in a. Nature does not do time. It just does motion. It is quite hard deprogramming your brain on this. But if you try hard, you will see that all we observe does not need time. Julian Barbour has about the same idea, but he calls it change. Now change and motion are not semantically the same, I understand change as a molecule forming a bond for instance, anyway Barbour does not explain what he means by change. And then he even does away with motion, as he renames and joins the time dimension �nd the many worlds interpretation of qm into "Platonia". The problem is that he wants to keep Mutual Time Dilation, and that is impossible without time dimension or "platonia". The question you need to ask yourself is : is what we perceive possible in a world with just 3d + motion ? Try to stay at Newtonian views first, and if you succeed, I will tell you how to add the relativistic stuff to this view. >>>> Caused by inertia. I suppose you could say that >>>> "time is a function of change of position". >>> That doesn't make sense. You can't say that position >>> has *changed* unless you have two different times to >>> compare those positions. >> These are only in your memory. That is playing tricks on >> you. Move a ball from a to b. > > What does "move" mean? You are in a 3d world, there are many positions. Just changing from one position to the other. Try to grasp that first, you do NOT need time for this. Then you could add the way things move, by adding inertia to the model. > You are engaging in circular > reasoning. To talk about "moving" a ball from a to b > means that at one time, the object is at a, and at > a later time, the object is at b. The fact that the object was in a, remains only in your memory, not in nature. The object has moved, period. It does not sit there anymore at time "a", except in your memory. And you could describe time "a" as "the past now when the object was in a. See, we used a position to describe "time", which emerges from motion and positions. But the "old" positions are gone, lost, only a memory or pictures remain. And these memories and pictures were also made of motion that captured the position of particles, and then remained conserved. > But that presupposes > that we already understand what "time" means. You want to order events with time. You have been thought so. Nature does not do that : events are ordered by inertia. An object has the move in a Newtonian way, it if it moves inertially through abcd, it has to go through a first, then b, then c, then d. Inertia does not permit it to go to c then back to b. (In qm this is possible, that is one reason I claim that inertia is missing there) Uwe Hayek. -- We are fast approaching the stage of the ultimate inversion : the stage where the government is free to do anything it pleases, while the citizens may act only by permission; which is the stage of the darkest periods of human history. -- Ayn Rand I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them. -- Thomas Jefferson. Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery. -- Winston Churchill.
From: Hayek on 28 Jul 2010 04:56 PD wrote: > On Jul 27, 1:35 pm, Hayek <haye...(a)nospam.xs4all.nl> wrote: >> Daryl McCullough wrote: >>> Hayek says... >>>> In the latest Now, every object has a velocity, >>>> setting direction and speed. >>> What does "velocity" mean, if not the derivative of >>> position with respect to time? >> It is like deprogramming a hare khrishna or something. :-) >> >> Imagine a three dimensional space. Just three dimensions. >> >> Now imagine an object in it. >> >> Now let this object move , and normalize its speed 1. >> >> When a second object covers twice the ground as the >> first then say it has speed 2. >> >> The position of the objects is called the Now. >> >> There is no past, no future, just the two objects and >> their changing positions. > > OK, let's parcel this out a little bit. > > What you are doing is establishing a change from one Now state to > another Now state. Call the latter Now'. > > At the moment, you do not have any notion of speed. All you have is a > DISPLACEMENT. > The DISPLACEMENT of the first object (call it O1) is 1. The > DISPLACEMENT of the second object (call it O2) is 2. > > Now and Now' must be distinguishable so that you can declare a unique > state of O1 to have a single position (at Now) as opposed to two. If > Now and Now' are not distinguishable, then you have no unique position > identifier for any object. Fine. Only the first Now ceases to exist, actually there never was a now, it was and still is "the current position of all the objects" . > The first thing to notice is that you have declared unilaterally that > you can describe these states unilaterally and unambiguously. That NOW > and NOW' are labels that can be applied to both O1 and O2. You haven't > said so, but it's worth asking whether those labels are independent of > reference frame. > > Where time comes in, is the observation that certain repeatable > processes can be reliably compared, and that they will always produces > a common ratio of countable progress. For example, one process might > be the swinging of a pendulum of a certain length. Another process > might be the emptying of a can of water through a hole in the bottom. > And it is noted that, initiating both processes with label Now and > terminating at another label Now', it is observed that the can of > water has emptied once and the pendulum has swung 187 times. If you > repeat this, you find the same ratio. This comparison of processes is > what we mean by, and how we declare a measurement of, time. Excellently said. But that confirms my view that time emerges from motion. And what you describe is inertia. And that is why I say that a clock is an inertiameter. If inertia were higher , then your pendulum would swing slower, and the water would empty slower. On the Earth's surface inertia is practically everywhere the same. That makes clocks useful for comparing motion. > In particular, what it means is that we will make a particular choice > of a process, say the swinging of that pendulum, and we will declare > that a Unit Process, or if you like, a Unit of Time. Then all > processes can be compared to this (with certain stipulations of > locality and relative rest). > > Speed, then, is simply marking a DISPLACEMENT between Now and Now', > and finding the ratio of that displacement to the number of those Unit > Processes. A long text for what I said in one sentence : >> Now let this object move , and normalize its speed 1. Uwe Hayek. -- We are fast approaching the stage of the ultimate inversion : the stage where the government is free to do anything it pleases, while the citizens may act only by permission; which is the stage of the darkest periods of human history. -- Ayn Rand I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them. -- Thomas Jefferson. Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery. -- Winston Churchill.
From: Hayek on 28 Jul 2010 05:02 artful wrote: > On Jul 28, 4:35 am, Hayek <haye...(a)nospam.xs4all.nl> wrote: >> Daryl McCullough wrote: >>> Hayek says... >>>> In the latest Now, every object has a velocity, >>>> setting direction and speed. >>> What does "velocity" mean, if not the derivative of >>> position with respect to time? >> It is like deprogramming a hare khrishna or something. :-) >> >> Imagine a three dimensional space. Just three dimensions. >> >> Now imagine an object in it. >> >> Now let this object move , and normalize its speed 1. >> >> When a second object covers twice the ground as the >> first then say it has speed 2. >> >> The position of the objects is called the Now. >> >> There is no past, no future, just the two objects and >> their changing positions. >> >> No need to define time or have a time dimension. > > How can an object move (or any change occur) if there is no time? > ANSWER: It can't. Everything moves around you, you yourself are just a bunch of moving molecules. Time is not pushing them, it is energy, and inertia keeps them moving. > Once philosophical definition of time is "that which allows things to > change". Nothing changes without motion. Motion does not need time. Time is just a "unit of motion", artificially defined for our convenience. If you deep-freeze something, the motion stops, and also the time stops. Time emerges from motion. Uwe Hayek. -- We are fast approaching the stage of the ultimate inversion : the stage where the government is free to do anything it pleases, while the citizens may act only by permission; which is the stage of the darkest periods of human history. -- Ayn Rand I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them. -- Thomas Jefferson. Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery. -- Winston Churchill.
From: Hayek on 28 Jul 2010 05:11
artful wrote: > On Jul 28, 12:04 am, Hayek <haye...(a)nospam.xs4all.nl> wrote: >> whoever wrote: >>> "Hayek" wrote in messagenews:4c4ebce5$0$22935$e4fe514c(a)news.xs4all.nl... >>>> Inertial wrote: >>>>> Anyway .. none of that has much to do with the answer >>>>> to Ken's re-statement of the same old train gedanken >>>>> that has been dealt with by SR for almost a century. >>>> I find a lot of flaws in these "gedanken". For instance, >>>> Einstein assumes that the event only takes place if you >>>> see the lightflash of the event in your frame of reference. >>> Wrong >>>> Light to me, is only an imperfect carrier of >>>> information, just as sound is. >>> Yes it is. Among other things >>>> With instantaneous communication, >>> No need. And by SR not possible >>>> and a correct >>>> definition of time, >>> We have one >> Ok, time is what you read on a clock. > > I didn't say that > >> Then, what is a clock ? > > A device for measuring time > >>>> and there is no such thing anymore >>>> as relativity of simultaneity. >>> So if you make up a different theory, then you don't get it >> It is not about "getting" it, it is abput expaining "it". > > Its neither that I was saying .. I was saying that if you make up a > different theory, then you don't end up getting relativity of > simultaneity. But that doesn't mean that such theory is valid .. it > would have to predict the time dilation that we DO observe > experimentally for a start. I get time dilation, but this is due to restrained motion by higher inertia. Time emerges from motion, then slower time emerges from slower motion. Relativity is ok. But then RoS, if time does not exist, and simultaneity means : "at the same time", things no longer at up. And I have defined time as an illusion emerging form motion. SR-ians do not define time. So, define time, before you talk about simultaneity. > >>> .. but does >>> that theory actually work in reality? >> Of course, it just explains things differently. > > Not all theory explain things correctly. They may be different, but > also wrong. You need a theory that gives you the time dilataion that > we see experimentally. > >> In the expectation to make further progress, to enlarge >> the understanding. > > Irrelevant if the theory isn't correct (ie doesn't predict/explain > what experiment shows us). SR *does* predict/explain experiment You get Ros with ANY speed limited information carrier. You do not need SR for that. >>>> Then again, I do not agree with the block universe, and >>>> accept the fact that the Now is the same everywhere in >>>> the universe. Just the clocks, just measuring inertia, >>>> measure higher or lower inertia, as an inertiameter >>>> should do. >>> Clocks don't measure inertial .. they measure (or mark) time. >> Then, what is time ? > > A dimension like (but not the same) as space. What is space? > >> To me, time emerges from motion. > > Motion requires time for it to occur .. you have things backward. Not at all. > > Anyway , your personal philosophy of what time means doesn't really > make a scrap of difference to physics It does. It certainly means for you have to start thinking again, instead of parroting. Uwe Hayek. -- We are fast approaching the stage of the ultimate inversion : the stage where the government is free to do anything it pleases, while the citizens may act only by permission; which is the stage of the darkest periods of human history. -- Ayn Rand I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them. -- Thomas Jefferson. Socialism is a philosophy of failure, the creed of ignorance, and the gospel of envy, its inherent virtue is the equal sharing of misery. -- Winston Churchill. |