Skua
If it was a spatial dimension we wouldn’t have to call it space-time because all of the dimensions would be space. 4D space is extremely difficult to imagine because our brains are built for a 3D world.
Think about a cube for a moment. That’s a 3D object. You could take a 2D slice out of it and imagine that, right? The slice you take out of it might be a square, or a triangle, or a trapezium. It depends on the angle and position of the slice.
Now let’s scale that up to taking a 3D “slice” out of a 4D object. You’re still doing the same thing, taking a lower-dimensional piece of a higher-dimensional object. So we know that a cube is an object in which every side is parallel to another side, all internal angles are 90 degrees, and all sides are the same length. It’s like the 3D equivalent to a 2D square, right? We can generalise that up to 4D even if we can’t picture it. This shape is called a hypercube or a tesseract. Taking a slice out of a tesseract that’s one dimension lower, like we did with taking a 2D slice out of a 3D cube, would give us a 3D object.
As it is, we have no direct evidence of spatial dimensions beyond the third existing. Some theories do propose the existence of them in order to find answers to very difficult problems in physics - string theory, for example - but as far as I know none of them are generally accepted to be likely to be true. It’s a case of “the maths works out if we assume this” but we do not have evidence upon which to assume it.
Temporal dimensions - time, that is - work quite differently to spatial ones. Things don’t seem to be able to move freely in time like they do in space. In fact they can seemingly only go in one direction in time. It’s sometimes useful to consider time as a 4th dimension in the overall space-time because it allows us to do useful maths with it that seems to line up wth real life (particularly with regard to relativity and how moving close to the speed of light in spatial dimensions affects things), but that doesn’t mean that time is space.
The volume of 4D is duration
Duration is only a measure of the scale of something in time. It’s like length, it’s a measure in one dimension. Say you have a 3D shape. You know that all of the internal angles are 90 degrees and all of the sides are parallel to another side. In other words, it’s a cuboid box, right? If you know the volume of this box and you also know two lengths (say, height and width), you can calculate the third length, right? And if your box is 4D and you know the 4D volume and three lengths, you can work out the fourth length. However, if you know the duration and two lengths you have no idea about what the third length is. It could be anything.
“Four-dimensional space” and “tesseract” are probably good wikipedia articles to start with. Not Tessearct the prog metal band though.
Bunch of dickheads apparently feeling attacked in these comments
Wait, people actually avoid Australia because of it? I mean, I do think of Australian wildlife as dangerous, but to me that means “don’t fuck about” rather than “don’t go at all”. And I live in the UK, where we killed everything that was even slightly dangerous to humans long ago
Most of my brewing is for beer, so I have heaps of 500ml bottles that I use to make cuts, thankfully. I don’t actually own any tools to properly measure the content of spirits, though. I’m currently going on “is it flammable” and “what does it taste/smell like”. If I can actually get into it a bit more I’ll invest in the gear, but I feel like I need to get over the mental block first
I appreciate the advice though. It’s good to have some reassurance, because man it just fucking sucks to wait weeks to brew something and then totally fuck up the distillation. What’s the thinking behind covering the jars with a paper towel rather than just the lid of the jar (or the stopper of the bottle, in my case)?
