3 ms·
Something like (from Wikipedia): > In the presence of gravity spacetime is described by a curved 4-dimensional manifold for which the tangent space to any poin
by blackbear_ 2y ago
Something like (from Wikipedia):
> In the presence of gravity spacetime is described by a curved 4-dimensional manifold for which the tangent space to any point is a 4-dimensional Minkowski space.
Perhaps? A good way to lose 99% of the readers before the end of the first sentence.
- mise_en_place 2y agoJust represent it in a 4x4 multidimensional array that corresponds to the metric tensor.
- hn_throwaway_99 2y agoYes, that will really pull in the laymen...
- nvader 2y agoReminds me of the mathematician who was asked how he mentally visualizes a 4 dimensional space. "I simply imagine an n-dimensional space, and then set n to 4"
- homebrewer 2y ago>>> After Hilbert was told that a student in his class had dropped mathematics in order to become a poet, he is reported to have said "Good--he did not have enough imagination to become a mathematician" https://scienceworld.wolfram.com/biography/Hilbert.html https://scienceworld.wolfram.com/biography/Hilbert.html
- golly_ned 2y agoReminds me of Geoffrey Hinton who, when asked how to imagine a 14-dimensional space, said: “imagine a 3-dimensional space, and say ‘fourteen’ very loudly”
- esperent 2y agoThis is great, can't believe I haven't heard it before.
- deleted 2y ago[deleted]
- zbobet2012 2y agoI'm a huge fan of providing laymen explanations. And at some point if you _actually_ want to understand you have to stop using those and pickup and understand the math. http://therisingsea.org/post/mast30026/ http://therisingsea.org/post/mast30026/ Has a good introduction to space, and the notion of a manifold, and what a Minkowski space is.
- verzali 2y agoOk, but almost nobody is going to read an article that requires you to work through 21 lectures, 9 tutorials, and 3 assignments first. It'd be great if they did, and it'd be nice to give the link for interested people, but otherwise it is just making the subject inaccessible to almost everyone.
- slashdave 2y agoThat's in the article on Minkowski space. It's actually a good summary, with a hyperlink to manifold. Here's the introduction to the "spacetime" page: > In physics, spacetime, also called the space-time continuum, is a mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams are useful in visualizing and understanding relativistic effects, such as how different observers perceive where and when events occur.