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Geography is four-dimensional

sive.rs

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Re: Geography is four-dimensional

#11

Post by ySteeK »

deweller wrote: post #4
soco wrote: post #3

I get the latitude, longitude, and they added time. But what was the fourth dimension? Or third rather, because the post assumption is that time was the fourth added.

Altitude is the third dimension, but I presume you knew that. "Geography is three dimensional" doesn't correctly communicate the time dimension.

Even with altitude, you still need time. The Earth moves around the Sun, the Sun around the galactic center, all at hundreds of km/s. Without a timestamp, lat/long/alt just tells you where something was, not where it is. Time was never optional.

Re: Geography is four-dimensional

#13

Post by finghin »

incognito124 wrote: post #9
soco wrote: post #3

I get the latitude, longitude, and they added time. But what was the fourth dimension? Or third rather, because the post assumption is that time was the fourth added.

The lat and lon are actually 3d since we live, up to a first approximation, on the surface of a sphere. The correct way to think about it is xyz in a reference frame anchored in the center of the Earth

If you accepted that nothing exists at the north pole, that’s enough to obtain meaningful 2d coordinates for a location:)

Not workable in practice, though!

Re: Geography is four-dimensional

#14

Post by zimpenfish »

notachatbot123 wrote: post #10
soco wrote: post #5

Earlier quoted context omitted.

Hmm I thought that, but we don't really live in a 3D world (or use the altitude parameter in a very meaningful way in life) so I wondered whether there's something else I was missing.

I wonder what makes you belittle the altitude dimension? Buildings have storys, humans can sit and stand, birds can fly, your eyes can move up and down your monitor.

Also the altitude of a given lat/long can change due to geological processes, climate processes, war, etc.

Re: Geography is four-dimensional

#15

Post by marginalia_nu »

deweller wrote: post #4
soco wrote: post #3

I get the latitude, longitude, and they added time. But what was the fourth dimension? Or third rather, because the post assumption is that time was the fourth added.

Altitude is the third dimension, but I presume you knew that. "Geography is three dimensional" doesn't correctly communicate the time dimension.

You can model geography as a 2D heightmap to a pretty good approximation tbh.

Re: Geography is four-dimensional

#16

Post by JNORLIN »

soco wrote: post #3

I get the latitude, longitude, and they added time. But what was the fourth dimension? Or third rather, because the post assumption is that time was the fourth added.

The fourth is altitude. I asked a colleague how he found Vietnam. I was surprised to hear him say it said it was windy, desolate, and cold as hell. It did not match my experience at all. Turns out he had been hanging out at 30 000 feet the whole time!

Re: Geography is four-dimensional

#18

Post by dibujaron »

marginalia_nu wrote: post #15
deweller wrote: post #4

Earlier quoted context omitted.

Altitude is the third dimension, but I presume you knew that. "Geography is three dimensional" doesn't correctly communicate the time dimension.

You can model geography as a 2D heightmap to a pretty good approximation tbh.

a heightmap is three-dimensional, where the third dimension is usually represented with color or contour lines.

Re: Geography is four-dimensional

#19

Post by marginalia_nu »

dibujaron wrote: post #18
marginalia_nu wrote: post #15

Earlier quoted context omitted.

You can model geography as a 2D heightmap to a pretty good approximation tbh.

a heightmap is three-dimensional, where the third dimension is usually represented with color or contour lines.

A mathematically ideal sheet of paper in a 3d-dimensional space can be addressed with both 2D coordinates, within the reference frame of the paper, and 3D coordinates, within the 3D space, but given that the paper has a location in space, 2D coordinates are sufficient to specify a point in 3D space.

You can do the same with geography. It's why generally only specify geographical coordinates with latitude and longitude, altitude is a given from those two, since you're as unlikely to be hovering in the air as you are to be immersed in bedrock.

Re: Geography is four-dimensional

#20

Post by wenc »

soco wrote: post #5
deweller wrote: post #4

Earlier quoted context omitted.

Altitude is the third dimension, but I presume you knew that. "Geography is three dimensional" doesn't correctly communicate the time dimension.

Hmm I thought that, but we don't really live in a 3D world (or use the altitude parameter in a very meaningful way in life) so I wondered whether there's something else I was missing.

If you lived in a high place (Denver), you will find it different from a flat lowland (Chicago).

Also in Rio, how high you live can be a marker depending on which part of town you are. Favelas are on hills, whereas wealthy people in Zona Sul live down the hill closer to the beaches.

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