What are space and time?
in [Physics]
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From: Immortalist on 7 Jul 2010 22:40 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. Hamlyn http://www.amazon.com/exec/obidos/tg/detail/-/0521286905/
From: Sir Frederick Martin on 7 Jul 2010 23:23 On Wed, 7 Jul 2010 19:40:44 -0700 (PDT), Immortalist <reanimater_2000(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. Hamlyn >http://www.amazon.com/exec/obidos/tg/detail/-/0521286905/ There are probably 'higher' dimensional aspects to the situation. Whatever that means? The place is quite mysterious, and 'we' are quite 'stuck' 'herein'. Other than that 'we' have 'our' model stories, perhaps that's all 'we' can handle. What is anything in 'itself'? More mystery. BTW, I resent the shallow understanding with which 'we' seem to be stuck. In the meanwhile, 'higher' dimensional measurements and considerations are very interesting. Even negative results, such as the 'recent' studies of gravity over millimeter distances. Some of the 'space' studies are 'higher' dimension oriented. String theory, though surprisingly productive, remains very non intuitive.
From: Sam Wormley on 8 Jul 2010 00:10 On 7/7/10 9:40 PM, Immortalist wrote: > What sort of things are they if they are things? Some Background http://en.wikipedia.org/wiki/Spacetime "The concept of spacetime combines space and time to a single abstract "space", for which a unified coordinate system is chosen. Typically three spatial dimensions (length, width, height), and one temporal dimension (time) are required. Dimensions are independent components of a coordinate grid needed to locate a point in a certain defined "space".
From: Michael C on 8 Jul 2010 01:00 On Jul 7, 10:40 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/ Immortalist, I think a moment in time is a certain configuration of the universe. Now, it's not enough to just know where the atoms in the universe are located in that "moment in time". You'd have to include things like momentum and the directions they are "currently" moving. Now, does this definition still allow time to be the fourth dimension? Well, if a moment in time is a configuration of the universe, then it seems that knowing what moment in time the universe is currently at would be enough to describe everything, length, width and height and then some of all the objects in it. Is time an all inclusive dimension - does dimension simply mean piece of information about an object? If you know what time it is, would you know the length, width, height and locatons (and anything else) of all the universe's objects? Michael C
From: Michael C on 8 Jul 2010 01:26
On Jul 8, 1:00 am, Michael C <michaelcochr...(a)gmail.com> wrote: > On Jul 7, 10:40 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/ > > Immortalist, > > I think a moment in time is a certain configuration of the > universe. Now, it's not enough to just know where the atoms in the > universe are located in that "moment in time". You'd have to include > things like momentum and the directions they are "currently" moving. > Now, does this definition still allow time to be the fourth > dimension? Well, if a moment in time is a configuration of the > universe, then it seems that knowing what moment in time the universe > is currently at would be enough to describe everything, length, width > and height and then some of all the objects in it. Is time an all > inclusive dimension - does dimension simply mean piece of information > about an object? If you know what time it is, would you know the > length, width, height and locatons (and anything else) of all the > universe's objects? > > Michael C- Hide quoted text - > > - Show quoted text - Also, if a moment in time is a configuration of the universe, then it seems that traveling "back to" a certain moment in time is a little more possible in theory. To travel to a certain moment in time, you'd have to change the configuration of the universe to that "moment in time". Doing this seems quite difficult if the configuration you want to move to is quite different from the current one. You could focus on a very local area of the universe and change the configuration there. In doing so, you may be able to travel to (change to) a time (configuration) that is sufficient for your purposes. Michael C |