Stargate address confusion

[razafishaha]

OK, so each stargate has 39 symbols, one of which is the "point of origin" (PoO). Normal dialling involves 6 non-PoO symbols followed by the PoO symbol.

In an early episode there was a picture on a whiteboard in the background which looked like this one: http://en.wikipedia.org/wiki/Image%3...oordinates.png

I think Sam was explaining that an address represents 6 different points in space - the endpoints of the three lines in the diagram above. The actual destination point is the intersection of those three lines.

Can anyone confirm this ? It seems a little wasteful, as the three lines would rarely intersect at the same point. And only two lines are really necessary (which may not intersect, either).

A couple of alternatives (which I am not suggesting are true, but could also work):

1. The 6 symbols could represent a single coordinate in space (using some absolute frame of reference), as XXYYZZ. This would allow for 38x38 = 1444 units for the X, Y and Z coordinates, which is about right for the size of the milky way (diameter = approx. 100000 light years, so stargates would need to be at least 70 light years apart from each other, assuming the startgate system spans the whole milky way galaxy).

2. A distance and a direction would also work (DDDXYZ), but this doesn't seem to fit with the idea that the same address works from different locations ... unless it is not the distance and direction from that gate itself, but a common point (such as the centre of the galaxy).

David Fisher (new poster)

[TechnoWraith]

to locate a point in 3-dimensional space, you need 3 coordinates: an X-axis, a Y-axis and a Z-axis. Each axis corresponds to a plane. There's 3 planes: height, width and depth. Space is three dimensional, so you need 3 coordinates to locate a defined point within that space.

The stargates map out a coordinate system based on the assumption that to obtain a coordinate on a single plane, it needs symbols. These symbols correspond to the start and end points of a line on any of the X,Y and Z-axis planes. Where those three lines intersect in space is the location of the point the stargate wants to find. The six points correspond to the first six chevrons of a gate address. The final chevron (number 7) is your point of origin. You can't plot a connection without a PoO, as the stargate network can't determine where the wormhole is beginning.

The stargate address in and of itself really doesn't point to "an exact point" in space. Rather it constructs the reference points that leads to the exact point in space that particular address corresponds to.

[Bragi]

to locate a point in 3-dimensional space, you need 3 coordinates: an X-axis, a Y-axis and a Z-axis. Each axis corresponds to a plane. There's 3 planes: height, width and depth. Space is three dimensional, so you need 3 coordinates to locate a defined point within that space.

The stargates map out a coordinate system based on the assumption that to obtain a coordinate on a single plane, it needs symbols. These symbols correspond to the start and end points of a line on any of the X,Y and Z-axis planes. Where those three lines intersect in space is the location of the point the stargate wants to find. The six points correspond to the first six chevrons of a gate address. The final chevron (number 7) is your point of origin. You can't plot a connection without a PoO, as the stargate network can't determine where the wormhole is beginning.

The stargate address in and of itself really doesn't point to "an exact point" in space. Rather it constructs the reference points that leads to the exact point in space that particular address corresponds to.

Sam would be so proud.

[Pasankoon]

But Razafishaha was asking if that is the case why six you only need 2 of the lines not 3 to locate a point even if the line system was used.

[TechnoWraith]

But Razafishaha was asking if that is the case why six you only need 2 of the lines not 3 to locate a point even if the line system was used.

You need three lines.

One line determines the location of the point on the X-axis.
One line determines the location of the point on the Y-axis.
One line determines the location of the point on the Z-axis.

Remember that space is three dimensional. You need three axes (the plural of axis) to determine a point. (One axis tells you "how high a point is" relative to your position; one axis tells you "whether the point is to the left or right of your relative position"; one axis tells "how far back" the point is from your relative position. If only two lines were used, you would not get an exact pinpoint on a point in space. You would always be missing one of the axes, therefore you would miss the point.

[section31]

so...can someone explain how this XYZ thing works with 8 cheverons? 6 to locate a point in space, 1 cheveron to specify the target galaxy, 8th as a point of origin?

[razafishaha]

You need three lines.

One line determines the location of the point on the X-axis.
One line determines the location of the point on the Y-axis.
One line determines the location of the point on the Z-axis.

Remember that space is three dimensional. You need three axes (the plural of axis) to determine a point.

Are you saying that the stargate uses an absolute coordinate system, ie. the X, Y and Z axes (which are planes in 3D) are already defined, before you enter any coordinates ? I thought you were saying in your last post that the first three symbols define the axes (which doesn't seem possible unless they are all at right angles to each other).

I think I am missing your point (no pun intended).

With respect to Pasankoon's post - yes, that is what I am asking about:
The intersection of three planes will always give you a single point, unless two of them are parallel ... but two (or three) lines in space don't necessarily intersect. And if they do, you only need two lines to define the intersection point, not three ...

Maybe a picture would help ?

Trying not to be too frustrating, but genuinely wanting to sort this out,

David Fisher

[TechnoWraith]

Are you saying that the stargate uses an absolute coordinate system, ie. the X, Y and Z axes (which are planes in 3D) are already defined, before you enter any coordinates ? I thought you were saying in your last post that the first three symbols define the axes (which doesn't seem possible unless they are all at right angles to each other).

I think I am missing your point (no pun intended).

With respect to Pasankoon's post - yes, that is what I am asking about:
The intersection of three planes will always give you a single point, unless two of them are parallel ... but two (or three) lines in space don't necessarily intersect. And if they do, you only need two lines to define the intersection point, not three ...

Maybe a picture would help ?

Trying not to be too frustrating, but genuinely wanting to sort this out,

David Fisher

I'm going on the assumption that the gates use an absolute coordinate system. Somebody had a pic somewhere in a thread relating to this issue. i'll see if i can dig it up. The way i explained it is how i think and understand about how the gates work with locating points in space. It may not be 100% accurate, but it's the way i see how it works. If there are other ways to make the system work, i'm all ears. What i'm saying is not canon, or written in stone anywhere. I'm open for suggestions.

Edit: For a picture relating to my explanation, see the link in the very first post of this thread.

[Pazuzu]

O, man....this kind of thread again....It was another thread identical to this one and it was perfectly explained in that one.
The idea of the 3 axes is that, using 4 stargate coordinates(2 lines instead of 3) you might not find 2 lines that actually intersect in a desired destination in space, so you need 3 lines.
Remember that the stargate does not know where you want to go, you have to tell it. I, a thinking being, I can find only 2 lines that intersect in that point, because I know where that point is.

[Pazuzu]

Somebody had a pic somewhere in a thread relating to this issue. i'll see if i can dig it up.

It's not a very clear image but it's enough to understand it.
The point is that when I look from above, line 1 and 2, appear to intersect at the destination point, but they don't. That point is somwhere along that imaginary line of intersection(the dotted one). One needs the exact coordinates(where on that line) of the desired destination. For that you need a 3'rd line that intersects the imaginary line.

[razafishaha]

O, man....this kind of thread again....It was another thread identical to this one and it was perfectly explained in that one.

Could you give a reference to that thread ? I have been looking, but I haven't found one with a clear explanation yet (or one with a direct quote from the series).

The idea of the 3 axes is that, using 4 stargate coordinates(2 lines instead of 3) you might not find 2 lines that actually intersect in a desired destination in space, so you need 3 lines.

Three lines makes the situation even worse than with two ... with two lines, you can find a point on each line that is "closest" to the other line, and then I suppose take the midpoint of that line as the destination point. But with three lines, which point do you choose ?

Maybe you could find the closest point to the third line lying on the previously mentioned line, and that would give you a definite point in space ... but I am just making this up.

There are plenty of ways to take six coordinates and get a position in space, but I am more interested in what the show actually says about it (and whether the description in the first is correct).

Thanks,

David Fisher

[Pazuzu]

[IMG]In stargate, the first 2 lines that are determined by the position of constellations 1,2,3,4 may not actually intersect each other. They appear to intersect only if you are looking from above, being perpendicular on the XoY plane(in my drawing it's the Y axis).
If you are parallel to the XoY plane, then you can see that they're not intersecting and you need a 3'rd line to determine the virtual point of intersection. Only after you know that point can you make the translation of the first to lines in order for them to actually intersect each other.

In SGUniverse, you actually know where in space you want to go, but you must tell the stargate where is that point in space. For that you must use the constellations on the stargate and it might be very possible that you will not be able to determine 2 lines (formed from any of those constellations) that actually are intersecting each other. If you do find them, well, that's a particular case.
You might find a multitude of virtual intersection points, that are forming a 3'rd line. The position of the receiving stargate is somwhere along that 3'rd line, but you must know at what height that point is to know for sure where the second gate is. For that you need another 2 constellations to determine a new line that is intersecting the virtual line made by the virtual points of intersections.

Am I making any sense here?

This is from the previous thread, http://forum.gateworld.net/showthrea...t=26361&page=3

[razafishaha]

This is from the previous thread, http://forum.gateworld.net/showthrea...t=26361&page=3

Thanks for that reference - I'll go and have a good read and come back when I'm done ...

David Fisher

[Pazuzu]

Thanks for that reference - I'll go and have a good read and come back when I'm done ...

David Fisher

No problemo. You're welcome

[razafishaha]

Originally Posted by razafishaha

Thanks for that reference - I'll go and have a good read and come back when I'm done ...

OK, back again ...

Interesting stuff, but I would still like to know what they say in the actual episodes of Stargate.

(... unending faith in the writers to get things right ...)

It still makes more sense to me not to have an absolute coordinate system, but for everything to be relative to the positions of the constellations shown on the stargate (which change over time, but never mind).

David Fisher