<!--QuoteBegin--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> </td></tr><tr><td id='QUOTE'><!--QuoteEBegin-->Time = movement. Dimensions = stable. I don't really agree with time being a dimension.<!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd-->
I'm not well versed in this topic, but I think I have to disagree with you. ^^ This is really a beginners guide to explain what a Dimension is, but it works with movement so ... : <ul><li>We start with an 0D Objekt. It is a point in its mathematical meaning. (an entity in space with no extent) It has no length, nor height, nor depth. In a 0D Universe there could be nothing but this point, which we can hardly imagine.
</li><li>So how do get to a first Dimension ? Well we "just" have to endlessly move that dot in a direction. The space it has passed is a line. <i>This is very simplified. You would have to move it in one direction and in its oposite direction at the same time so that the line has no start nor end. But its hard to move a single point in 2 direction endlessly at the same time. To make it possible you would have to alternate the directions at each step. </i> However ... We can choose an interval from this line and can formulate a proporsion which we may call length.</li></ul>We can iterate this method, and gain the other Dimensions we know.<ul><li>Moving that line in an orthogonal angle to its direction leads to a infinite plane. You can describe an (simple) area in this plane by its length and a new proportion we may call height.</li><li>Moving this plane orthogonally ends up in an endless 3-Dimensional space. Our new propotion is depth.</li></ul> The great question is ... can we go on with that ? What happens if we move that "room" in a direction. ... which direction ? That is a good question, because our simple imagination ends here. Perhaps we can move it in time ?!
A little story could make this plausible. Imagine a 2-D World. Little squares and triangles living on a plane happily. They can not notice that their plane is part of 3-Dimensional World. They do not know what depth might be. But one day a sphere looks at this little 2-D world and wants to make its inhabitants understand what the third dimension is. But how can it explain this to them ? But the sphere is very wise and calm and reveals itself to a little square. The sphere moves itself through the plane. All the little square recognizes is a circle coming out of nowhere which grows to a maximum and then shrinks again until its gone. The little square already mazed is told by the sphere that it is all these circles at the same time. The little square is so excited that it "runs" to its friends an tells them about its experience.
This story has an open end. The little square might become a professor, but perhaps its friends will just hate it for telling weird stuff about a lifeform from the third dimension. (some might call it god :-b)
But I think this story can visualize what time is for us. We can just see a very small cut through time which is our presence. Everything else of time lies in front or behind of our presence in some way. ^^ This makes me think, that time is the fourth dimension ^^
<!--QuoteBegin-Trevelyan+Jul 30 2005, 01:16 PM--></div><table border='0' align='center' width='95%' cellpadding='3' cellspacing='1'><tr><td><b>QUOTE</b> (Trevelyan @ Jul 30 2005, 01:16 PM)</td></tr><tr><td id='QUOTE'><!--QuoteEBegin--> although it would make sense that god is/in another dimension... humans explodeded when they see him/her/t it. <!--QuoteEnd--></td></tr></table><div class='postcolor'><!--QuoteEEnd--> I think you might wanna rephrase that Trevelyan- look at my quote if you don't know what I mean
Yeah that is from a book called 'Flatland' I think, about a whole society of 'Flats' and suddenly a 'Lord Sphere' shows a 'square' the third dimension. Remember were talking about dimensions here, not the kind of dimensions in D&D where you meet aliens, and unicorns and all that ****...
You can imagine extra dimensions as points, then lines, then planes, then cubes, then...what? We can't imagine the 4th dimension, human brains weren't developed that way. Just like how a 'flat being' has no idea what 'up' and 'down' is, we don't know anything how to visualize the fourth dimension. There are some cool tricks to get an idea of what they might look like, but they are too complicated of illusions to explain here.
nah, its called a hypercube, just google image search it.
you can do it on paper as an optical illusion, just like drawing a cube is really just diagonal 2D lines, you can draw a hypercube with a bunch of diagonal 2d lines as well.
Time aint a dimension, as it is not traversable in two directions by common logic, too many paradoxes (see Back To The Future). We can alter our travel forward through general relativity (if you go too fast your progression in time will slow down and it will seem as if the rest of the universe is leaping ahead of you, you will think you have moved forward in time.)
the thing about dimensions is that they allow for SO much more information! imagine a bunch of little 2D squares, say thats 32 MB of information, now extend that into the third dimension, and how much information do you have? at every infenitesimal slice in 3d youve got a whole nother copy (slightly altered perhaps) as a frame. this means you would have 32MB times the number of frames! infinite if you wanted it to be.
an animated GIF image is a composition of frames, it is a progression of 2d information, a motion-hologram would be a motion captured 3d space, and could conceptually be a rendition of 4-space. this doesnt make time the fourth dimension,as you saw with the GIF image example, time there was a third dimension. Time is simply an easy way to imagine an extra dimension.
now do Five.
if you try to imagine the possibilities of five dimensions of space, youll soon learn that that D&D fantasy dimension bullcarp is starting to sound pretty plausible.
er well, time does not necesserily need to be the fourth dimension. It is indeed more plausible that time is the first Dimension. And you can handle time like any other dimension in math. You can even define a hyperplane for time: presence. You can't say time isn't a dimension, just because we can't imagine things going backwards ~~
What I dislike about string theory, is that they have undescribable many variables to define a string universe. And they are trying to find the right values for our standart universe. But there are infinite possible stringuniverses, and they have a hard time to find the rightone ~~
I read something about "loop quantum gravity", which states that the universe at its lowest level is something like a foam, consisting of lines and nodes. This foam isn't placed in time and space, it IS time and space. This model is based on 3+1 dimensions, and includes time. Like string theorie it has smart and weak sides. I had a small essay about it, but i lost it somehow. You can visit wikipedia for further information. I read the german version, but there is one in english too.
I don't think we will reveal the nature of time in this thread. As the contradictory theories: Superstring and loop-quantum-gravity show ... scientists still disagree about this. ^^
EpidemicDark Force GorgeJoin Date: 2003-06-29Member: 17781Members
<!--quoteo(post=1549125:date=Jul 28 2005, 09:14 PM:name=Trevelyan)--><div class='quotetop'>QUOTE(Trevelyan @ Jul 28 2005, 09:14 PM) [snapback]1549125[/snapback]</div><div class='quotemain'><!--quotec--> Perhaps there is an after-life. Perhaps once we are free of these pointless mounds of flesh we call our bodies... we are able to understand/expirience something beyond any living creature could comprehend. <!--QuoteEnd--></div><!--QuoteEEnd--> OR not, hahahahahahhahahaha
Epidemic, you should know better. Thread necromancy, without a reasonable addition to the discussion, is what will bring about the end days!
But, as this topic is nice, light, above all politically neutral, and much needed for everyone's heads (including mine) to cool down, anyone want to get it going again?
tankefuglOne Script To Rule Them All...Trondheim, NorwayJoin Date: 2002-11-14Member: 8641Members, Retired Developer, NS1 Playtester, Constellation, NS2 Playtester, Squad Five Blue
edited November 2006
Alright.
Time can be, according to Einstein's theory of special relativity, the fourth dimension. Whether you believe it or not based on your <i>intuition</i> is irrelevant, as special relativity is strongly counter-intuitive anyway. (Although it has been experimentally proved to be more accurate than the more intuitive Newtonian counterpart.)
The simple version: We, as human beings, cannot concieve traveling along this time axis any other way than forward in a rather constant speed (1 second per .. eh, second?), but particles moving close to or at the speed of light move along the time axis at a very different speeds. The faster you move in the three spatial dimensions (width, length, depth), the slower you move in the time-dimension.
As an 2d-example, you can consider a car moving at 10mph in a straight line. It can move at full speed along the X-axis, and zero speed along the Y axis, or the other way around. It can also move diagonally, resulting in a 7mph speed along either axis. You can then replace the Y-axis with the label "time", and try to envision it.
As for superstring theory: It's just that, a theory. (Actually, it's 6 <u>different</u> theories last I checked.) The 11+ dimensions required for it to work is all an abstract piece of mathematics that only apply to some of these theories, other special cases require even more. What's common for all these extra dimensions is that they are curled and so small that we cannot percieve any movement along either of them. A particle can move as much as it wants along a 10th-dimension-axis, and still not be visibly changed for us.
Mathematically, dimensions are decided by the size of the basis of the spanned space (math lingo), so in that sense we can even consider electric charge and "quantum coloring" as a dimensions, although I am very unsure on how exactly this is incorporated into string theories.
In any case, it's a very exotic subject with a lot thought-gymastics, and very challenging for the imagination as it defies all common sense <img src="style_emoticons/<#EMO_DIR#>/wink-fix.gif" style="vertical-align:middle" emoid=";)" border="0" alt="wink-fix.gif" />
EpidemicDark Force GorgeJoin Date: 2003-06-29Member: 17781Members
edited November 2006
<!--quoteo(post=1579353:date=Nov 21 2006, 04:40 AM:name=Rob)--><div class='quotetop'>QUOTE(Rob @ Nov 21 2006, 04:40 AM) [snapback]1579353[/snapback]</div><div class='quotemain'><!--quotec--> Epidemic, you should know better. Thread necromancy, without a reasonable addition to the discussion, is what will bring about the end days!
But, as this topic is nice, light, above all politically neutral, and much needed for everyone's heads (including mine) to cool down, anyone want to get it going again?
Anyone? <!--QuoteEnd--></div><!--QuoteEEnd--> I did not necro it though, check the post above mine. But right on, shame on me for posting something useless. The reason it might seem light and political neutral, is probably because it appears this thread started out in the off-topic forum and later got moved to the discussion. See #1 reply in this thead and the fact that a large number of individual who wouldn't have posted on this discussion forum, have replied to this thread.
Feel free to delete my replies once you have read em.
<!--quoteo(post=1579353:date=Nov 21 2006, 04:40 PM:name=Rob)--><div class='quotetop'>QUOTE(Rob @ Nov 21 2006, 04:40 PM) [snapback]1579353[/snapback]</div><div class='quotemain'><!--quotec--> Epidemic, you should know better. Thread necromancy, without a reasonable addition to the discussion, is what will bring about the end days!
But, as this topic is nice, light, above all politically neutral, and much needed for everyone's heads (including mine) to cool down, anyone want to get it going again?
Anyone? <!--QuoteEnd--></div><!--QuoteEEnd--> Actually, NoArms_NoCookies is responsible, not Epidemic.
Oh, wow, yeah. Sorry, Epidemic! I just saw the new post, saw it was you, and immediately assumed you were the culprit. My mistake, again apologies. Guess I'm having a rough day all around (been biting off people's heads at work, too)
Anyway, I'll stop now. The necromancy was justified. Let me not fill the thread with anymore useless garbage.
My interest in physics has somewhat waned over the years (the fact I haven't taken a science class in 3 years and a physics-based class in 4 proves my point), but in the discussions of a dimension here I've just got to wonder how you'd exactly want to define a dimension.
Now, time might be arguable, since we don't really have any sort of means of going backwards through it...
But what about magnetism? Forgive me if my knoweldge of megnetism is somewhat simplfied, but every atom has (at least to a certain degree) a volume and some form of charge. Since magnetic fields essentially go out until infinitey, growing weaker with distance, couldn't it be conceivable to consider them a dimension? In a similar vein I'd also like to call attention to gravity, but as far as I know there's not a negative or positive form of gravity...it just is...but it to stretches to infinity, weakening with distance. Gravity might be pushing it (requires mass, but there's not really negative mass...unless you count antimatter as negative mass...but I don't think the gravity from matter and antimatter cancels out)...maybe my thinking is just too reliant on physically measurable data.
Then again, I don't know if all those exotic particle types have a particular charge, but whatever. I'm also not sure if electron and proton charges are absolute or just tend to be very similar (of course, if they're all of exactly the same structure you'd expect them to have the same charge anyway).
Thinking too much about time, and time dilation events, makes your head hurt.
As near as I can tell, objects moving at the speed of light do not experience the passage of time. At all. Now, this is mostly a moot point, as its impossible to actually accelerate an object to the speed of light, unless it is completely massless. But does this mean that light itself does not experience the passage of time?
I havent quite thought through whether this means anything or not. But its a fun thought experiment. =)
a_civilianLikes seeing numbersJoin Date: 2003-01-08Member: 12041Members, NS1 Playtester, Playtest Lead
edited November 2006
Some thoughts on time-
It is somewhat deceptive to consider "movement through time" in the same way one would consider movement through space. There are very important differences.
Consider first an object moving through space from some spatial point P1 to another point P2. When the object is at P1, it is not at P2. After the object moves to P2, it is no longer at P1.
Now consider an object moving through spacetime from some spacetime point Q1 to another point Q2. Immediately we can see that there is no longer the notion that the object ceased to exist at Q1 when it moved to Q2. For the object continues to exist at Q1, Q2, and all other points along its world line (or hypercylinder). (If you don't see this, consider that even after the object moves to Q2, it is still true that the object existed at Q1; the history of its spatial position does not cease to exist.)
So how, then, do we define movement through time? We could try to preserve as much of the previous notion as we can and consider it as some sort of passage through the infinite sequence of the object's spacetime positions. But passage of what? It cannot be the object that is moving here; the object <i>is</i> this sequence of spacetime points.
Now it should be apparent why movement through time is not analogous to movement through space. Indeed, our movement through time is somewhat of a mystery to physics. At the microscopic level, all interactions are time-reversible* - they look the same whichever time direction we consider as forward. It is only at the macroscopic level that we get a clear direction for time, provided by entropy. Perhaps the only reason we experience passage of time, then, is that the entropy of our brains increases in the "positive" time direction. But that is only speculation.
<!--sizeo:1--><span style="font-size:8pt;line-height:100%"><!--/sizeo-->*Actually there are some weak (as in weak force) interactions that are time-irreversible, but they bear no relation to everyday experience.<!--sizec--></span><!--/sizec-->
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->As near as I can tell, objects moving at the speed of light do not experience the passage of time. At all. Now, this is mostly a moot point, as its impossible to actually accelerate an object to the speed of light, unless it is completely massless. But does this mean that light itself does not experience the passage of time?<!--QuoteEnd--></div><!--QuoteEEnd--> In the reference frame of any observer moving at less than the speed of light, a photon does not experience passage of time. However, it is meaningless to consider whether the photon experiences passage of time in its own frame, for in its own frame, space along its axis of movement is contracted to zero length. Thence it takes zero time, in its own frame, for the photon to travel any distance whatsoever.
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->unless you count antimatter as negative mass...but I don't think the gravity from matter and antimatter cancels out<!--QuoteEnd--></div><!--QuoteEEnd--> Antimatter is identical to "normal" matter except that any given antiparticle carries the opposite electric charge as its "ordinary" counterpart. They have the same mass.
tankefuglOne Script To Rule Them All...Trondheim, NorwayJoin Date: 2002-11-14Member: 8641Members, Retired Developer, NS1 Playtester, Constellation, NS2 Playtester, Squad Five Blue
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->Now consider an object moving through spacetime from some spacetime point Q1 to another point Q2. Immediately we can see that there is no longer the notion that the object ceased to exist at Q1 when it moved to Q2. For the object continues to exist at Q1, Q2, and all other points along its world line (or hypercylinder). (If you don't see this, consider that even after the object moves to Q2, it is still true that the object existed at Q1; the history of its spatial position does not cease to exist.)<!--QuoteEnd--></div><!--QuoteEEnd-->
I'm not sure I follow you completely on that one.
If you consider spacetime to be four-dimensional, then you cannot talk about "cease to exist at point Q1" because the existance of the object is now a time-dependant notion. It'd be better to consider the object at the coordinates Q1 = [X, Y, Z, T], where it would cease to exist (at that particular position) if any of the four components change, for example T (for time).
(Movement is most commonly regarded as a change in the three spatial coordinates as a function of time, but we could possibly regard movement as change along any three dimensions with respect to any axis. I have not yet explored this subject myself though, so just consider it a somewhat crazy idea.)
I do agree with you that an object is the set of its spacetime points; that is a very nice definition of existence.
As for the subject of entropy and time-reversible processes; exciting subject, but I have very little to contribute to this.
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->But what about magnetism? Forgive me if my knoweldge of megnetism is somewhat simplfied, but every atom has (at least to a certain degree) a volume and some form of charge. Since magnetic fields essentially go out until infinitey, growing weaker with distance, couldn't it be conceivable to consider them a dimension?<!--QuoteEnd--></div><!--QuoteEEnd-->
A part of the superstring theories is connecting these forces (magnetism is a part of electromagnetism, which is one of the four forces of the universe) to the very geometry of the dimensions in the universe, both large (the three big spatial), time and "exotic" (in lack of a better word).
So yeah, the idea itself is good, and it's being explored.
a_civilianLikes seeing numbersJoin Date: 2003-01-08Member: 12041Members, NS1 Playtester, Playtest Lead
edited November 2006
<!--quoteo(post=1579632:date=Nov 22 2006, 08:09 AM:name=tankefugl)--><div class='quotetop'>QUOTE(tankefugl @ Nov 22 2006, 08:09 AM) [snapback]1579632[/snapback]</div><div class='quotemain'><!--quotec-->If you consider spacetime to be four-dimensional, then you cannot talk about "cease to exist at point Q1" because the existance of the object is now a time-dependant notion. It'd be better to consider the object at the coordinates Q1 = [X, Y, Z, T], where it would cease to exist (at that particular position) if any of the four components change, for example T (for time).<!--QuoteEnd--></div><!--QuoteEEnd--> I am somewhat lost with your first sentence, but I will try to explain further.
Consider again this object moving from Q1(P1, t1) to Q2(P2, t2). At t2, the object is at P2. But at t2, <i>it is also true that the object was at P1 at time t1</i>. In other words, it still exists at Q1.
Or think of it this way. Spacetime must be a static world, for there is no exterior notion of time by which objects can move in this world.
<!--quoteo(post=1579632:date=Nov 22 2006, 08:09 AM:name=tankefugl)--><div class='quotetop'>QUOTE(tankefugl @ Nov 22 2006, 08:09 AM) [snapback]1579632[/snapback]</div><div class='quotemain'><!--quotec-->(Movement is most commonly regarded as a change in the three spatial coordinates as a function of time, but we could possibly regard movement as change along any three dimensions with respect to any axis. I have not yet explored this subject myself though, so just consider it a somewhat crazy idea.<!--QuoteEnd--></div><!--QuoteEEnd--> That is fully plausible, but doesn't really help us. We could consider movement through time as the velocity along the time axis with respect to some spatial axis, say the x-axis. However, this only gives us the reciprocal of the velocity along the x-axis with respect to time, and thus only really tells us about our velocity through space.
tankefuglOne Script To Rule Them All...Trondheim, NorwayJoin Date: 2002-11-14Member: 8641Members, Retired Developer, NS1 Playtester, Constellation, NS2 Playtester, Squad Five Blue
<!--quoteo(post=1579715:date=Nov 22 2006, 07:01 PM:name=a_civilian)--><div class='quotetop'>QUOTE(a_civilian @ Nov 22 2006, 07:01 PM) [snapback]1579715[/snapback]</div><div class='quotemain'><!--quotec--> Consider again this object moving from Q1(P1, t1) to Q2(P2, t2). At t2, the object is at P2. But at t2, <i>it is also true that the object was at P1 at time t1</i>. In other words, it still exists at Q1.
Or think of it this way. Spacetime must be a static world, for there is no exterior notion of time by which objects can move in this world. <!--QuoteEnd--></div><!--QuoteEEnd-->
I think we're trying to say the same thing, I was only reacting to the way you used terms such as "still exists" or "cease to exist", as those depend on time as a reference. Or they do in day-to-day use of the words.
Anyway, it doesn't matter. I basically agree with you.
tankefuglOne Script To Rule Them All...Trondheim, NorwayJoin Date: 2002-11-14Member: 8641Members, Retired Developer, NS1 Playtester, Constellation, NS2 Playtester, Squad Five Blue
Edit: (Seem's we're working on this as a live document atm. <img src="style_emoticons/<#EMO_DIR#>/tounge.gif" style="vertical-align:middle" emoid=":p" border="0" alt="tounge.gif" />)
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->That is fully plausible, but doesn't really help us. We could consider movement through time as the velocity along the time axis with respect to some spatial axis, say the x-axis. However, this only gives us the reciprocal of the velocity along the x-axis with respect to time, and thus only really tells us about our velocity through space.<!--QuoteEnd--></div><!--QuoteEEnd-->
Yes, but it helps the visualisation on the subject of time vs. the three commonly accepted spatial dimensions.
It might be that using the approach when accounting for curvature through space can yield some interesting results, but I haven't tried it myself nor seen it done, so it's purely speculation on my part.
Perhaps this is enjoyable viewing: <a href="http://www.tenthdimension.com/flash.php" target="_blank">http://www.tenthdimension.com/flash.php</a>
I'm thinking time paradoxes can be seen as reactions caused by you doing something - comparatively, if you push the edge of an object, the whole object changes, not just the edge. The problem with that is how you can't do anything at a later point to change what happened at an earlier point.
Comments
I'm not well versed in this topic, but I think I have to disagree with you. ^^ This is really a beginners guide to explain what a Dimension is, but it works with movement so ... :
<ul><li>We start with an 0D Objekt. It is a point in its mathematical meaning. (an entity in space with no extent) It has no length, nor height, nor depth. In a 0D Universe there could be nothing but this point, which we can hardly imagine.
</li><li>So how do get to a first Dimension ? Well we "just" have to endlessly move that dot in a direction. The space it has passed is a line. <i>This is very simplified. You would have to move it in one direction and in its oposite direction at the same time so that the line has no start nor end. But its hard to move a single point in 2 direction endlessly at the same time. To make it possible you would have to alternate the directions at each step. </i> However ... We can choose an interval from this line and can formulate a proporsion which we may call length.</li></ul>We can iterate this method, and gain the other Dimensions we know.<ul><li>Moving that line in an orthogonal angle to its direction leads to a infinite plane. You can describe an (simple) area in this plane by its length and a new proportion we may call height.</li><li>Moving this plane orthogonally ends up in an endless 3-Dimensional space. Our new propotion is depth.</li></ul>
The great question is ... can we go on with that ? What happens if we move that "room" in a direction. ... which direction ? That is a good question, because our simple imagination ends here. Perhaps we can move it in time ?!
A little story could make this plausible. Imagine a 2-D World. Little squares and triangles living on a plane happily. They can not notice that their plane is part of 3-Dimensional World. They do not know what depth might be. But one day a sphere looks at this little 2-D world and wants to make its inhabitants understand what the third dimension is. But how can it explain this to them ? But the sphere is very wise and calm and reveals itself to a little square. The sphere moves itself through the plane. All the little square recognizes is a circle coming out of nowhere which grows to a maximum and then shrinks again until its gone. The little square already mazed is told by the sphere that it is all these circles at the same time. The little square is so excited that it "runs" to its friends an tells them about its experience.
This story has an open end. The little square might become a professor, but perhaps its friends will just hate it for telling weird stuff about a lifeform from the third dimension. (some might call it god :-b)
But I think this story can visualize what time is for us. We can just see a very small cut through time which is our presence. Everything else of time lies in front or behind of our presence in some way. ^^ This makes me think, that time is the fourth dimension ^^
I think you might wanna rephrase that Trevelyan- look at my quote if you don't know what I mean
You can imagine extra dimensions as points, then lines, then planes, then cubes, then...what? We can't imagine the 4th dimension, human brains weren't developed that way. Just like how a 'flat being' has no idea what 'up' and 'down' is, we don't know anything how to visualize the fourth dimension. There are some cool tricks to get an idea of what they might look like, but they are too complicated of illusions to explain here.
you can do it on paper as an optical illusion, just like drawing a cube is really just diagonal 2D lines, you can draw a hypercube with a bunch of diagonal 2d lines as well.
Time aint a dimension, as it is not traversable in two directions by common logic, too many paradoxes (see Back To The Future). We can alter our travel forward through general relativity (if you go too fast your progression in time will slow down and it will seem as if the rest of the universe is leaping ahead of you, you will think you have moved forward in time.)
the thing about dimensions is that they allow for SO much more information! imagine a bunch of little 2D squares, say thats 32 MB of information, now extend that into the third dimension, and how much information do you have? at every infenitesimal slice in 3d youve got a whole nother copy (slightly altered perhaps) as a frame. this means you would have 32MB times the number of frames! infinite if you wanted it to be.
an animated GIF image is a composition of frames, it is a progression of 2d information, a motion-hologram would be a motion captured 3d space, and could conceptually be a rendition of 4-space. this doesnt make time the fourth dimension,as you saw with the GIF image example, time there was a third dimension. Time is simply an easy way to imagine an extra dimension.
now do Five.
if you try to imagine the possibilities of five dimensions of space, youll soon learn that that D&D fantasy dimension bullcarp is starting to sound pretty plausible.
What I dislike about string theory, is that they have undescribable many variables to define a string universe. And they are trying to find the right values for our standart universe. But there are infinite possible stringuniverses, and they have a hard time to find the rightone ~~
I read something about "loop quantum gravity", which states that the universe at its lowest level is something like a foam, consisting of lines and nodes. This foam isn't placed in time and space, it IS time and space. This model is based on 3+1 dimensions, and includes time. Like string theorie it has smart and weak sides. I had a small essay about it, but i lost it somehow. You can visit wikipedia for further information. I read the german version, but there is one in english too.
I don't think we will reveal the nature of time in this thread. As the contradictory theories: Superstring and loop-quantum-gravity show ... scientists still disagree about this. ^^
Perhaps there is an after-life. Perhaps once we are free of these pointless mounds of flesh we call our bodies... we are able to understand/expirience something beyond any living creature could comprehend.
<!--QuoteEnd--></div><!--QuoteEEnd-->
OR not, hahahahahahhahahaha
But, as this topic is nice, light, above all politically neutral, and much needed for everyone's heads (including mine) to cool down, anyone want to get it going again?
Anyone?
Time can be, according to Einstein's theory of special relativity, the fourth dimension. Whether you believe it or not based on your <i>intuition</i> is irrelevant, as special relativity is strongly counter-intuitive anyway. (Although it has been experimentally proved to be more accurate than the more intuitive Newtonian counterpart.)
The simple version: We, as human beings, cannot concieve traveling along this time axis any other way than forward in a rather constant speed (1 second per .. eh, second?), but particles moving close to or at the speed of light move along the time axis at a very different speeds. The faster you move in the three spatial dimensions (width, length, depth), the slower you move in the time-dimension.
As an 2d-example, you can consider a car moving at 10mph in a straight line. It can move at full speed along the X-axis, and zero speed along the Y axis, or the other way around. It can also move diagonally, resulting in a 7mph speed along either axis. You can then replace the Y-axis with the label "time", and try to envision it.
As for superstring theory: It's just that, a theory. (Actually, it's 6 <u>different</u> theories last I checked.) The 11+ dimensions required for it to work is all an abstract piece of mathematics that only apply to some of these theories, other special cases require even more. What's common for all these extra dimensions is that they are curled and so small that we cannot percieve any movement along either of them. A particle can move as much as it wants along a 10th-dimension-axis, and still not be visibly changed for us.
Mathematically, dimensions are decided by the size of the basis of the spanned space (math lingo), so in that sense we can even consider electric charge and "quantum coloring" as a dimensions, although I am very unsure on how exactly this is incorporated into string theories.
In any case, it's a very exotic subject with a lot thought-gymastics, and very challenging for the imagination as it defies all common sense <img src="style_emoticons/<#EMO_DIR#>/wink-fix.gif" style="vertical-align:middle" emoid=";)" border="0" alt="wink-fix.gif" />
Epidemic, you should know better. Thread necromancy, without a reasonable addition to the discussion, is what will bring about the end days!
But, as this topic is nice, light, above all politically neutral, and much needed for everyone's heads (including mine) to cool down, anyone want to get it going again?
Anyone?
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I did not necro it though, check the post above mine. But right on, shame on me for posting something useless. The reason it might seem light and political neutral, is probably because it appears this thread started out in the off-topic forum and later got moved to the discussion. See #1 reply in this thead and the fact that a large number of individual who wouldn't have posted on this discussion forum, have replied to this thread.
Feel free to delete my replies once you have read em.
Epidemic, you should know better. Thread necromancy, without a reasonable addition to the discussion, is what will bring about the end days!
But, as this topic is nice, light, above all politically neutral, and much needed for everyone's heads (including mine) to cool down, anyone want to get it going again?
Anyone?
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Actually, NoArms_NoCookies is responsible, not Epidemic.
Anyway, I'll stop now. The necromancy was justified. Let me not fill the thread with anymore useless garbage.
Now, time might be arguable, since we don't really have any sort of means of going backwards through it...
But what about magnetism? Forgive me if my knoweldge of megnetism is somewhat simplfied, but every atom has (at least to a certain degree) a volume and some form of charge. Since magnetic fields essentially go out until infinitey, growing weaker with distance, couldn't it be conceivable to consider them a dimension? In a similar vein I'd also like to call attention to gravity, but as far as I know there's not a negative or positive form of gravity...it just is...but it to stretches to infinity, weakening with distance. Gravity might be pushing it (requires mass, but there's not really negative mass...unless you count antimatter as negative mass...but I don't think the gravity from matter and antimatter cancels out)...maybe my thinking is just too reliant on physically measurable data.
Then again, I don't know if all those exotic particle types have a particular charge, but whatever. I'm also not sure if electron and proton charges are absolute or just tend to be very similar (of course, if they're all of exactly the same structure you'd expect them to have the same charge anyway).
Hopefully this post isn't too crazy.
As near as I can tell, objects moving at the speed of light do not experience the passage of time. At all. Now, this is mostly a moot point, as its impossible to actually accelerate an object to the speed of light, unless it is completely massless. But does this mean that light itself does not experience the passage of time?
I havent quite thought through whether this means anything or not. But its a fun thought experiment. =)
It is somewhat deceptive to consider "movement through time" in the same way one would consider movement through space. There are very important differences.
Consider first an object moving through space from some spatial point P1 to another point P2. When the object is at P1, it is not at P2. After the object moves to P2, it is no longer at P1.
Now consider an object moving through spacetime from some spacetime point Q1 to another point Q2. Immediately we can see that there is no longer the notion that the object ceased to exist at Q1 when it moved to Q2. For the object continues to exist at Q1, Q2, and all other points along its world line (or hypercylinder). (If you don't see this, consider that even after the object moves to Q2, it is still true that the object existed at Q1; the history of its spatial position does not cease to exist.)
So how, then, do we define movement through time? We could try to preserve as much of the previous notion as we can and consider it as some sort of passage through the infinite sequence of the object's spacetime positions. But passage of what? It cannot be the object that is moving here; the object <i>is</i> this sequence of spacetime points.
Now it should be apparent why movement through time is not analogous to movement through space. Indeed, our movement through time is somewhat of a mystery to physics. At the microscopic level, all interactions are time-reversible* - they look the same whichever time direction we consider as forward. It is only at the macroscopic level that we get a clear direction for time, provided by entropy. Perhaps the only reason we experience passage of time, then, is that the entropy of our brains increases in the "positive" time direction. But that is only speculation.
<!--sizeo:1--><span style="font-size:8pt;line-height:100%"><!--/sizeo-->*Actually there are some weak (as in weak force) interactions that are time-irreversible, but they bear no relation to everyday experience.<!--sizec--></span><!--/sizec-->
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->As near as I can tell, objects moving at the speed of light do not experience the passage of time. At all. Now, this is mostly a moot point, as its impossible to actually accelerate an object to the speed of light, unless it is completely massless. But does this mean that light itself does not experience the passage of time?<!--QuoteEnd--></div><!--QuoteEEnd-->
In the reference frame of any observer moving at less than the speed of light, a photon does not experience passage of time. However, it is meaningless to consider whether the photon experiences passage of time in its own frame, for in its own frame, space along its axis of movement is contracted to zero length. Thence it takes zero time, in its own frame, for the photon to travel any distance whatsoever.
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->unless you count antimatter as negative mass...but I don't think the gravity from matter and antimatter cancels out<!--QuoteEnd--></div><!--QuoteEEnd-->
Antimatter is identical to "normal" matter except that any given antiparticle carries the opposite electric charge as its "ordinary" counterpart. They have the same mass.
I'm not sure I follow you completely on that one.
If you consider spacetime to be four-dimensional, then you cannot talk about "cease to exist at point Q1" because the existance of the object is now a time-dependant notion. It'd be better to consider the object at the coordinates Q1 = [X, Y, Z, T], where it would cease to exist (at that particular position) if any of the four components change, for example T (for time).
(Movement is most commonly regarded as a change in the three spatial coordinates as a function of time, but we could possibly regard movement as change along any three dimensions with respect to any axis. I have not yet explored this subject myself though, so just consider it a somewhat crazy idea.)
I do agree with you that an object is the set of its spacetime points; that is a very nice definition of existence.
As for the subject of entropy and time-reversible processes; exciting subject, but I have very little to contribute to this.
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->But what about magnetism? Forgive me if my knoweldge of megnetism is somewhat simplfied, but every atom has (at least to a certain degree) a volume and some form of charge. Since magnetic fields essentially go out until infinitey, growing weaker with distance, couldn't it be conceivable to consider them a dimension?<!--QuoteEnd--></div><!--QuoteEEnd-->
A part of the superstring theories is connecting these forces (magnetism is a part of electromagnetism, which is one of the four forces of the universe) to the very geometry of the dimensions in the universe, both large (the three big spatial), time and "exotic" (in lack of a better word).
So yeah, the idea itself is good, and it's being explored.
I am somewhat lost with your first sentence, but I will try to explain further.
Consider again this object moving from Q1(P1, t1) to Q2(P2, t2). At t2, the object is at P2. But at t2, <i>it is also true that the object was at P1 at time t1</i>. In other words, it still exists at Q1.
Or think of it this way. Spacetime must be a static world, for there is no exterior notion of time by which objects can move in this world.
<!--quoteo(post=1579632:date=Nov 22 2006, 08:09 AM:name=tankefugl)--><div class='quotetop'>QUOTE(tankefugl @ Nov 22 2006, 08:09 AM) [snapback]1579632[/snapback]</div><div class='quotemain'><!--quotec-->(Movement is most commonly regarded as a change in the three spatial coordinates as a function of time, but we could possibly regard movement as change along any three dimensions with respect to any axis. I have not yet explored this subject myself though, so just consider it a somewhat crazy idea.<!--QuoteEnd--></div><!--QuoteEEnd-->
That is fully plausible, but doesn't really help us. We could consider movement through time as the velocity along the time axis with respect to some spatial axis, say the x-axis. However, this only gives us the reciprocal of the velocity along the x-axis with respect to time, and thus only really tells us about our velocity through space.
Consider again this object moving from Q1(P1, t1) to Q2(P2, t2). At t2, the object is at P2. But at t2, <i>it is also true that the object was at P1 at time t1</i>. In other words, it still exists at Q1.
Or think of it this way. Spacetime must be a static world, for there is no exterior notion of time by which objects can move in this world.
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I think we're trying to say the same thing, I was only reacting to the way you used terms such as "still exists" or "cease to exist", as those depend on time as a reference. Or they do in day-to-day use of the words.
Anyway, it doesn't matter. I basically agree with you.
<!--quoteo--><div class='quotetop'>QUOTE</div><div class='quotemain'><!--quotec-->That is fully plausible, but doesn't really help us. We could consider movement through time as the velocity along the time axis with respect to some spatial axis, say the x-axis. However, this only gives us the reciprocal of the velocity along the x-axis with respect to time, and thus only really tells us about our velocity through space.<!--QuoteEnd--></div><!--QuoteEEnd-->
Yes, but it helps the visualisation on the subject of time vs. the three commonly accepted spatial dimensions.
It might be that using the approach when accounting for curvature through space can yield some interesting results, but I haven't tried it myself nor seen it done, so it's purely speculation on my part.
<a href="http://www.tenthdimension.com/flash.php" target="_blank">http://www.tenthdimension.com/flash.php</a>
I'm thinking time paradoxes can be seen as reactions caused by you doing something - comparatively, if you push the edge of an object, the whole object changes, not just the edge.
The problem with that is how you can't do anything at a later point to change what happened at an earlier point.