What are space and time?
in [Physics]
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From: PD on 16 Jul 2010 11:38 On Jul 7, 9:40 pm, Immortalist <reanimater_2...(a)yahoo.com> wrote: > What sort of things are they if they are things? > > One natural answer is that they comprise continua, three-dimensional > in the case of space, one-dimensional in the case of time; that is to > say that they consist of continuous manifolds, positions in which can > be occupied by substances and events respectively, and which have an > existence in their own right. > > It is in virtue of the occupancy of such positions that events and > processes are to be seen as taking place after each other and > substances are to be seen in certain spatial relations. > > Or do space and time have properties of their own independent of the > objects and events that they contain? > > Did Einstein show, through his theory of relativity, that since space > and time can change in shape and duration that space and time are more > complex than just sustained perceptual constants? > > Metaphysics - by D. W. Hamlynhttp://www.amazon.com/exec/obidos/tg/detail/-/0521286905/ From a physics perspective, "things" are identified by their properties, where said properties are regulated, described, or predictable according to certain systematic regularities called physical laws. It isn't really necessary to try to drop things into categories of things in order to do that. Categories usually end up being broken most easily in our deepening understanding of nature. Categories that we think are mutually exclusive and/or exhaustive frequently end up being neither. For example, it is tempting to call an electron a particle, or to call it a wave, where we take those two things to be mutually incompatible categories and into which the electron MUST fall somewhere. This turns out to be a bad idea. However, it is perfectly acceptable to describe an electron by its *properties*, especially properties like electric charge, spin, parity, momentum, and so on, which are of interest because of their role in physical laws. By this description, space and time are physical entities because they have properties in their own right, and those properties are of interest in physical laws. PD
From: Androcles on 16 Jul 2010 13:45 "Paul A. Suhler" <suhler(a)pollux.usc.edu> wrote in message news:i1prju$a95$1(a)pollux.usc.edu... | Where and when would you like the answer? | Here and now, please.
From: glird on 16 Jul 2010 15:32 On Jul 16, 11:38 am, PD <thedraperfam...(a)gmail.com> wrote: > From a physics perspective, "things" are identified by their > properties, where said properties are regulated, described, or > predictable according to certain systematic regularities called > physical laws. > It isn't really necessary to try to drop things into categories of > things in order to do that. Categories usually end up being broken > most easily in our deepening understanding of nature. Categories that > we think are mutually exclusive and/or exhaustive frequently end up > being neither. For example, it is tempting to call an electron a > particle, or to call it a wave, where we take those two things to be > mutually incompatible categories and into which the electron MUST fall > somewhere. This turns out to be a bad idea. Yeup. > However, it is perfectly > acceptable to describe an electron by its *properties*, especially > properties like electric charge, spin, parity, momentum, and so on, > which are of interest because of their role in physical laws. Regardless of their role in the mathematical equations that are called "physical laws", what IS an electric "charge"; the electron has no "spin"; in what way and with what does an electron have "parity"; and momentum (mv) requires an electron to have mass=weight in any g- field. > By this description, space and time are physical entities because they > have properties in their own right, and those properties are of > interest in physical laws. Independently of anything in it, what are the "properties" of space? Independently of the mathematical properties of clocks, what is "time" and what are its physical properties? glird
From: Huang on 17 Jul 2010 10:35 > > > > > What sort of things are they if they are things? > Space and time are indeed things. They are not abstractions or merely instruments neccessitated by physical laws, they are the substance of which everything consists. Space and time are indeed tangible substance, no different than any other substance. They are the most fundamental substance, everything is composed of space and time and all of chemistry and physics should be constructible based on the bending of these things. The strange thing about space and time is that it is very much like fundamental particles in the sense that a particle, say an electron may be regarded as being particle or wave. Space has some of these same properties and that is why it is poorly understood IMO. Some people argue it is continuous. Other argue it is discrete. It has properties of both, and yet continuous and discrete seem incompatible kind of like wave/particle aspects. The truth is that you can correctly model particles as being waves or particles. And you can correctly model space as being continuous or discrete. Both views are correct. The difficulty lies in resolving that and making it rigorous with the tools that you have been given, and unfortunately those tools are insufficient to model such a thing. If space is discretized - I ask - discretized BY WHAT ??? The only way to chop or demark a chunk of space which exists, is to place cuts into it which are nonexistent. That is the only way to chop up the existent. You chop it up into segments by inserting segments which are nonexistent - that is the only way. To do that you must be able to grasp triviality, order, disorder, and conservation......all in a very new way. No scientist today has been trained to think like that and most wold reject the approach. But it does not matter whether someone likes it or not. If you can produce accurate models which are consistent with observations in the lab then you have a useful model. It is very straightforward to model this way, yes you have tools which are not math, but are consistent with math, and equally as valid as mathematics though they be not math.
From: Huang on 17 Jul 2010 11:58
On Jul 17, 9:35 am, Huang <huangxienc...(a)yahoo.com> wrote: > > > > > What sort of things are they if they are things? > > Space and time are indeed things. They are not abstractions or merely > instruments neccessitated by physical laws, they are the substance of > which everything consists. > > Space and time are indeed tangible substance, no different than any > other substance. They are the most fundamental substance, everything > is composed of space and time and all of chemistry and physics should > be constructible based on the bending of these things. > > The strange thing about space and time is that it is very much like > fundamental particles in the sense that a particle, say an electron > may be regarded as being particle or wave. Space has some of these > same properties and that is why it is poorly understood IMO. Some > people argue it is continuous. Other argue it is discrete. It has > properties of both, and yet continuous and discrete seem incompatible > kind of like wave/particle aspects. > > The truth is that you can correctly model particles as being waves or > particles. And you can correctly model space as being continuous or > discrete. Both views are correct. The difficulty lies in resolving > that and making it rigorous with the tools that you have been given, > and unfortunately those tools are insufficient to model such a thing. > > If space is discretized - I ask - discretized BY WHAT ??? The only way > to chop or demark a chunk of space which exists, is to place cuts into > it which are nonexistent. That is the only way to chop up the > existent. You chop it up into segments by inserting segments which are > nonexistent - that is the only way. > > To do that you must be able to grasp triviality, order, disorder, and > conservation......all in a very new way. No scientist today has been > trained to think like that and most wold reject the approach. But it > does not matter whether someone likes it or not. If you can produce > accurate models which are consistent with observations in the lab then > you have a useful model. > > It is very straightforward to model this way, yes you have tools which > are not math, but are consistent with math, and equally as valid as > mathematics though they be not math. The fact that particles have this strange wave/particle duality is a direct result of the fact that such particles are composed of spacetime and spacetime alone. These strange wave/particle attributes are INHERITED from their mother material - spacetime. And that is why you have these strange effects in the first place. Modern physics and mathematics has FAILED to construct a spacetime which is possessing of such properties, and that is why any signifigant theoretical progress pretty much ends with Einstein who fathomed order, disorder and causality, but never quite conquered it. I dont blame him for keeping his mouth shut. After his death they confiscated his brain, and if he would have made such radical propositions they probably would have removed it from him while still alive. So - to math and physics I do hereby present you with your F, which I assign to you for failing mankind in this manner and preserving the ignorance. |