I was talking to a friend about the three dimensionality of a globe, and another friend chimes in to say that a globe is not as three dimensional as google earth. This seems ridiculous to me and I say so. He says that in google earth you can zoom in and look at things from different angles so it’s more 3d than a globe. I think he’s completely wrong and I’ve tried to explain it to him but I haven’t succeeded in convincing him.
I’m pretty sure he just has it wrong, but maybe I’m missing something? In order unequivocally locate any point on the globe you would have to have three coordinates, whereas with Google Earth you only need two for any one image. Perhaps taken as a whole the program is a representation of three dimensions, but it’s still just a two dimensional object.
I guess what I’m asking is two-fold. Am I right? And if I am, how do I convincingly explain why Google Earth is not 3d while a globe is?
First off, (unless I’m misunderstanding something) you only need two points to find something on a globe. Latitude and longitude. I’m not sure what the third point would be unless you’re working with a topographical globe, but that’s not usually the case. Remember, a globe is just a map wrapped around a sphere.
Secondly, I think you’re friend is confusing Google Earth/Maps with Google Street View. They used to be separate, but they’re more or less combined. So you go to Google Maps, click on satellite and you have Google Earth. Zoom in all the way and now you have Street View where you can see things (to a point) at different angles.
I think that’s the problem. We could, if we wanted, set the globe in some Cartesian coordinates and use (X,Y,Z) coordinates to find things, but we don’t have to since we have lat and long already on it.
I don’t think a globe is anymore 3D then a map.
A globe is a two-dimensional surface, curved in three dimensions - every point on it yields two co-ordinates in the local topology. Google Earth (NOT Google Maps or Street View) contains elevation data for every point, and also provides some visual information about height-above-ground for buildings and other structures. Even if you ignore the curvature of the Earth, the information can’t be presented with only two co-ordinates – it’s truly three-dimensional.
Your buddy is more right than you are. A globe is still laid out in 2D coordinates. You can put a fine pinpoint on Mount Everest or a large cliff but you can’t see how it rises and falls on a globe as a 4rd dimension. You can see altitude changes in Google Earth so that is the 3rd dimension a globe doesn’t have. You can do that with computer representations. That is still a 2D proxy when you see it on a screen but it better than any globe can do. Computer can also add a 4th dimension of time which globes cannot do either. You can take a digital photograph every second for example in a given place and represent change across time as well.
No, you need 3. It’s just that the 3rd one (height) usually defaults to surface level.
If you ask for coordinates to Van Cortlandt Park in New York City, 2 numbers will give you the latitude & longitude to locate it, assuming you want the surface of the park. If you want the Croton water reservoir underneath the park, you will need a 3rd number giving the depth you want underground.
You conveniently cut out the part where I said “unless you’re working with a topographical globe.” The default for most globes is that everything is flat. It’s pretty rare that you hand some a globe, give them lat and long and they look at you waiting for an elevation. Besides, if I wanted someone to find a water reservoir under a park, I don’t think I’d hand them a globe to find it on. In fact, I’d be surprised if there was a globe with the Crotan Water Reservoir on it to begin with.
A standard desk globe is a four dimensional object, like every other thing on the desk, three space dimensions, and a temporal dimension. Thing is, it also has a specific set of information stored on its surface, referencing another four dimensional object, The Earth. Some globes have color as a dimension referencing altitude above sea level or below sea level on the Earth. Globes on desks have no reference for temporal dimension, since they don’t change with changes on the Earth.
Google Earth is a virtual multi dimensional model of Earth, represented as two dimensional arrays of pixels on a computer screen. The pixels can add colors as an additional dimension, and can do so dynamically, overlaying multiple sets of information, some of which are virtually separate dimension of the virtual object. In addition, that virtual object has multiple hyper dimensions accessed from the two dimensional arrays. (street view, and hot links to other modes of investigation of the object.)
In fact, aside from it’s visual presentation, Google earth is a string of discrete elements of only two characteristics, on, or off. The rest of it is process. The virtual object has zero dimensions, since it is entirely imaginary. Or, it has many imaginary dimensions, if you prefer.
There is no way the friend is more right than the OP. Google Earth is presented on a 2D surface, and only pretends to be 3D. A globe actually exists in 3 dimensions.
You can argue that the friend has an equally valid view as described in posts above, but you cannot argue that his point of view is more accurate.
This is the bit that makes little sense. I suspect it’s nothing to do with dimensionality at all, but rather, navigability, accuracy, interactivity, usefulness, or something like that.
Google Earth does have a 3D option for viewing structures, etc (it’s one of the tick boxes in the menu), so I guess you could say it’s 3D in that sense. As for the globe, I think there’s confusion between the globe itself, which is 3D, and the map stretched around it, which plainly isn’t.
I dunno, I look at Google Earth on my computer, and it’s only got two dimensions for me. Maybe once I get one of those gee-whiz holographic projectors for my computer, it’ll be in 3D though.
The globe is obviously 3D. The lattitude/longitude system is also 3D, always has been, as any set of coordinates you find will give you a location in three dimensional space. The part folks are getting tripped up on is assuming that a line of Lattitude only has one dimension (ie: It’s a flat line). In fact, it actually has two dimensions, as it is in fact a circle (well, not quite a circle if I understand correctly, but that’s not the point here). The lines of Longitude similarly do not describe straight lines up and down, but rather describe half-rings (since a line of longitude doesn’t go all the way around north to south and back, unless I am misunderstanding my cartography).
Thus, a globe, and the lat/long coordinate system, by definition, is 3D.
Also, how can something be “More” or “Less” 3D? It’s not a spectrum, it’s a switch. It is or isn’t.
ETA: Oh, but I do use Google Maps for a lot more stuff than I use a Globe for. I’m trying to remember the last place I saw a globe…
All globes have street view, just not at the same resolution as Google Earth (for obvious reasons). Globes frequently have raised ridges for mountains, or colours representing altitude at ground level. Globes are also three-dimensional objects. Computer screens are not.
In short, the friend is an idiot who is confusing greater resolution for an extra dimension.
It has been a while since I looked at Google Earth, so I’m probably a couple of versions back, but the option that allowed to you tilt things around only gave the illusion of 3D. It did not actually allow you to see around all sides of a building, for example. It merely distorted the image proportions to give the illusion of “flying over” an area. It’s the same type of distortion used to correct keystoning in a projector.
I disagree - the lat/long system is two dimensional by definition, because it only requires two dimension measurements to describe any possible point on the map. It happens to be a 2D system mapped onto a sphere, instead of the plane surface we’re accustomed to thnking of when we talk about 2D, but that’s external, and entirely coincidental, to the space it describes.
The Lat/long system cannot describe points inside the Earth, or in the space surrounding it - you need a third dimension for that.
Latitude - longitude is a 2-dimensional system, as follows:
Latitude
Longitude
Any set of co-ordinates will give you a location on a 2-dimensional surface, namely the surface of the earth. To specify a location in 3-dimensional space would require a 3rd co-ordinate perpendicular to the surface.