eli5: what is 4D space?

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I just dont know what Is 4D space and i can’t imagine it…

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Anonymous 0 Comments

Say I invite you over for lunch and I give you my address like this: “I live at the corner of 6th street and 37th avenue, on the ninth floor, four units from the elevator.” So you write down (6, 37, 9, 4). These four numbers describe my location in space. This is technically still three-dimensional space, so I could give you this information with three numbers- my latitude, my longitude, and my altitude, but street numbers are quantized so we need the extra dimension to be more specific.

Four-dimensional space is a mathematical abstraction for people to do math in. It’s not important to be able to visualize all four dimensions. In 4D space, if you want to describe the location of a point you need to make a list of four numbers, like you did up there.

But dimensions don’t have to be spatial; they can be symbolic. Imagine a society where the only things you can eat for lunch are gyros, ice cream sandwiches, and Diet Pepsi™. Any possible lunch can be described with the number of gyros, ice cream sandwiches, and Diet Pepsi™ you ate, so every point in “lunch space” describes a unique lunch. Then, if lunch scientists figure out that you can also have an apple for lunch, then you would need an extra fourth dimension to describe every unique lunch.

Anonymous 0 Comments

While its a simplification – it might be easier to think about this using the time dimension.

This morning, I had a cookie on a plate on my desk. We can think about this being in 4D space. The cookie wasn’t on my desk in the afternoon but it was there in the morning. In 3D, we could only describe whether there the cookie is or isn’t on the desk but by adding another dimension – the cookie can be on the version of the desk in the morning & not on the one in the afternoon.

Anonymous 0 Comments

While its a simplification – it might be easier to think about this using the time dimension.

This morning, I had a cookie on a plate on my desk. We can think about this being in 4D space. The cookie wasn’t on my desk in the afternoon but it was there in the morning. In 3D, we could only describe whether there the cookie is or isn’t on the desk but by adding another dimension – the cookie can be on the version of the desk in the morning & not on the one in the afternoon.

Anonymous 0 Comments

While its a simplification – it might be easier to think about this using the time dimension.

This morning, I had a cookie on a plate on my desk. We can think about this being in 4D space. The cookie wasn’t on my desk in the afternoon but it was there in the morning. In 3D, we could only describe whether there the cookie is or isn’t on the desk but by adding another dimension – the cookie can be on the version of the desk in the morning & not on the one in the afternoon.

Anonymous 0 Comments

As far as we can tell, we live in a universe with 3 spatial dimensions. Anything that *exists* requires 3 distinct properties to describe it. Usually we assign these dimensions like “x,y,z” coordinates for a location, or “width, depth, height” for size.

4D space is a thought experiment where the universe – and the stuff within it – has a 4th spatial dimension.

There are different ways to try and imagine or visualize such objects, but the concept is difficult to grasp (our brains aren’t built for it) and ultimately they are artistic expressions not realistic simulations because there isn’t any tangible evidence that such a dimension exists or how it might work if it did.

Anonymous 0 Comments

As far as we can tell, we live in a universe with 3 spatial dimensions. Anything that *exists* requires 3 distinct properties to describe it. Usually we assign these dimensions like “x,y,z” coordinates for a location, or “width, depth, height” for size.

4D space is a thought experiment where the universe – and the stuff within it – has a 4th spatial dimension.

There are different ways to try and imagine or visualize such objects, but the concept is difficult to grasp (our brains aren’t built for it) and ultimately they are artistic expressions not realistic simulations because there isn’t any tangible evidence that such a dimension exists or how it might work if it did.

Anonymous 0 Comments

As far as we can tell, we live in a universe with 3 spatial dimensions. Anything that *exists* requires 3 distinct properties to describe it. Usually we assign these dimensions like “x,y,z” coordinates for a location, or “width, depth, height” for size.

4D space is a thought experiment where the universe – and the stuff within it – has a 4th spatial dimension.

There are different ways to try and imagine or visualize such objects, but the concept is difficult to grasp (our brains aren’t built for it) and ultimately they are artistic expressions not realistic simulations because there isn’t any tangible evidence that such a dimension exists or how it might work if it did.