Arrow of Causality
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From: Robert L. Oldershaw on 1 Jul 2010 19:17 On Jun 28, 6:08 am, Tom Roberts <tjroberts...(a)sbcglobal.net> wrote: See sci.physics.research : "Arrow of Time" -------------------------------------------------------- I have 3 comments on your last post. (1) In the Rube Goldberg set-up there is what we might call a linear causality. But this is a cartoon, and this is not the causality model I espouse. Take any spacetime point. It has a past light cone that distinguishes the set of events that are causally relatable to the specific spacetime point, and those that are not. There are an infinite number of causal events that can and do influence what happens at the specific spacetime point, many having infinitessimal effects and some having significant effects. As you get closer in time to the specific spacetime event the direct causal influences decrease in number and increase in relative significance. Causality in nature is not linear. It is more like an incredibly rich tapestry with an infinite number of causal threads, which can intimately interact. This is nicely discussed in the fine book by Ivars Ekeland titled "The Best Of All Possible Worlds". (2) So we have established that: Unlit match ---> Lit match, is a fully causal process. A separate issue is our ability to provide an exact model of that causal process. We could say that there is an "arrow of time" that dictates the motion-friction-heat-chemical reaction-fire ordering of events. Or we could say that the sequence of events is physically ordered by physical processes, e.g., initial heat triggers chemical reactions, which are exothermal and release additional heat, which raises the match head to the combustion temperature, and voila! Then I would ask whether time in some metaphysical way time orders the causal sequence or whether the sequence of causality orders what we calll relational "time". I see causality as more fundamental, and time as a less fundamental ordering relation. Perhaps that is a "naive" interpretation, or perhaps simplex signilum veri. (3) Some physics books say that electric charges are the direct and fully causal sources and sinks of the electric field. Are these physics texts wrong? RLO http://www3.amherst.edu/~rloldershaw/
From: Huang on 1 Jul 2010 20:46 Lets say that you have a dynamical system in nature, lets say it's a galaxy. The galaxy is composed of lots of self similar structures like atoms and whatnot, and its a big scalar fractal on multiple scales and maybe you can even model it somehow. Well, explain me this : What happens when you have a big chunk of it that decays due to radiodecay, or if your galaxy collides with another galaxy. Are two colliding galaxies to be regarded as a fractal somehow ? Maybe they are. Well, I need to see some math. Just saying it is a hand wave. I need to see a mathematical model, whether stochastic, nonstochastic, mixed, whatever, something that produces a universe on my computer screen when you hit the "enter" button.
From: Sam Wormley on 1 Jul 2010 23:53 On 7/1/10 6:17 PM, Robert L. Oldershaw wrote: > On Jun 28, 6:08 am, Tom Roberts<tjroberts...(a)sbcglobal.net> wrote: > See sci.physics.research : "Arrow of Time" > -------------------------------------------------------- > I have 3 comments on your last post. > > (1) In the Rube Goldberg set-up there is what we might call a > linear causality. But this is a cartoon, and this is not the > causality model I espouse. > > Take any spacetime point. It has a past light cone that > distinguishes the set of events that are causally relatable > to the specific spacetime point, and those that are not. > There are an infinite number of causal events that can > and do influence what happens at the specific spacetime > point, many having infinitessimal effects and some having > significant effects. As you get closer in time to the specific > spacetime event the direct causal influences decrease in > number and increase in relative significance. > > Causality in nature is not linear. It is more like an incredibly > rich tapestry with an infinite number of causal threads, which > can intimately interact. This is nicely discussed in the fine > book by Ivars Ekeland titled "The Best Of All Possible Worlds". > > (2) So we have established that: > > Unlit match ---> Lit match, > > is a fully causal process. > > A separate issue is our ability to provide an exact model of > that causal process. > > We could say that there is an "arrow of time" that dictates > the motion-friction-heat-chemical reaction-fire ordering of > events. Or we could say that the sequence of events is physically > ordered by physical processes, e.g., initial heat triggers > chemical reactions, which are exothermal and release additional > heat, which raises the match head to the combustion temperature, > and voila! > > Then I would ask whether time in some metaphysical way time > orders the causal sequence or whether the sequence of causality > orders what we calll relational "time". I see causality as more > fundamental, and time as a less fundamental ordering relation. > Perhaps that is a "naive" interpretation, or perhaps simplex signilum > veri. > > (3) Some physics books say that electric charges are the > direct and fully causal sources and sinks of the electric field. > Are these physics texts wrong? > > RLO > http://www3.amherst.edu/~rloldershaw/ You certainly did NOT address the fact that observation contradicts an infinitely infinite discrete hierarchy of self-similar systems making up the universe.
From: Robert L. Oldershaw on 2 Jul 2010 00:09 On Jul 1, 8:46 pm, Huang <huangxienc...(a)yahoo.com> wrote: > > Are two colliding galaxies to be regarded as a fractal somehow ? > > Well, I need to see some math. Just saying it is a hand wave. ------------------------------------------------------- Forget the math for now. Study nature, not Platonic symbols. Consider subatomic nuclei and galaxies. Their radii and spin periods and oscillation periods are related by the discrete self-similar scaling laws [which are mathematical, by the way] of Discrete Scale Relativity [which is mathematical; it's General Relativity with a new discrete self-similar symmetry included]. Ask yourself: do subatomic nuclei and galaxies do the same things. Most definitely! They are ultracompact objects that can collide and merge. They can become unstable and eject ultracompact objects from their interiors [think beta decay]. Can you identify any physical behavior that is not the same for these analogues on such vastly different size scales? Think about it. RLO www.amherst.edu/~rloldershaw
From: Sam Wormley on 2 Jul 2010 00:17
On 7/1/10 11:09 PM, Robert L. Oldershaw wrote: > Consider subatomic nuclei and galaxies. > > Their radii and spin periods and oscillation periods are related by > the discrete self-similar scaling laws [which are mathematical, by the > way] of Discrete Scale Relativity [which is mathematical; it's General > Relativity with a new discrete self-similar symmetry included]. > Actually they are not! |