[HN Gopher] Scientists Uncover the Universal Geometry of Geology...
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Scientists Uncover the Universal Geometry of Geology (2020)
Author : fanf2
Score : 58 points
Date : 2026-01-01 09:42 UTC (4 days ago)
(HTM) web link (www.quantamagazine.org)
(TXT) w3m dump (www.quantamagazine.org)
| metalman wrote:
| all/most materials can be foamed, ALL foam bubbles aproximate a
| very specific shape where each intersection is at the SAME angle,
| which is not 90deg so at minimum there are two "universal
| geometrys", and yes there are natural rock foams.
| az09mugen wrote:
| We could be in a Minecraft indeed ^^
| gnabgib wrote:
| (2020) Title: _Scientists Uncover the Universal Geometry of
| Geology_
| brennanpeterson wrote:
| Group theory and crystallograpy without either word? I suppose I
| can look at this as an extension of group theory to glassy and
| partial.domains, but it doesn't appear to offer much more.
|
| Columnar basalt formation has been understood for a long time, I
| really don't understand what this explained that wasn't already
| known?
| kayo_20211030 wrote:
| It doesn't even explain it particularly well. The reference to
| a taco cart was unexpected; it wasn't necessary, but an
| interesting literary device, I suppose. I just feel a good
| editor could have made it a better explainer. It's all over the
| place.
| MORPHOICES wrote:
| Why do distinct systems end up having the same look?
|
| I am often surprised to discover different systems that arrive at
| the same shapes.
|
| You will find it in nature, but also within.
|
| N/A
|
| Organizational charts.
|
| Patterns of traffic.
|
| Ways to Fail.
|
| Despite different inputs and histories they all yield the same
| outcome.
|
| I use a mental model of sorts.
|
| Local regulations and limits.
|
| Consistent application of weight.
|
| In the end, only a handful of stable shapes endure.
|
| I'm curious now.
|
| Are we overestimating the uniqueness of our systems?
|
| What design patterns to use in your product?
|
| Have you taken note of shapes showing up in different domains
| time and again? ~
| talkingtab wrote:
| This is really cool thinking. The fundamental concept I got out
| of it, was fracturing something means that it can fit together
| again, so there is a constraint. Of course, but cool. Thanks!
| jofer wrote:
| It may not be immediately obvious to folks outside of geoscience,
| but the main way something like this is useful is as a
| measure/metric to compare things. Looking at the number of faces
| of fractured pieces isn't normally something we do often in
| geology.
|
| Sure, the pieces average 6 faces when materials are relatively
| homogenous and iostropic (i.e. no preferential direction to break
| in and no free surface nearby). However, as they note in the
| article, this isn't always the case. Things like mud flats and
| other cases with very anisotropic materials and/or free surfaces
| nearby don't fracture with the same average.
|
| This is a good example of a potential metric that could be used
| to give some clues about overall material behavior even if all
| you have are the broken remains.
|
| Fractal dimension is also pretty esoteric. However, it's somewhat
| widely used in geoscience, even though what we're measuring isn't
| _actually_ fractal. It's still a very useful comparative metric,
| though, because it lets us measure how complex an interface or
| surface is quantitatively and scale-independent.
| 7777777phil wrote:
| It reminds me of how we use measures like the VIX in finance;
| not because markets are actually log-normal, but because having
| a standardized way to compare "choppiness" across different
| periods is incredibly useful. I like your fractal dimension
| example too. Even if real coastlines aren't truly fractal,
| being able to say "this coastline has dimension 1.3 vs 1.7"
| gives you meaningful information about erosion patterns, wave
| energy, and rock composition. The cube metric could work
| similarly for forensic geology.
| boi694206 wrote:
| nerdy ahh jit needs to sybau
| mmooss wrote:
| The paper is here:
|
| Gabor Domokos, Douglas J. Jerolmack. Plato's cube and the natural
| geometry of fragmentation. PNAS (2020)
|
| https://www.pnas.org/doi/10.1073/pnas.2001037117
|
| Abstract:
|
| _Plato envisioned Earth's building blocks as cubes, a shape
| rarely found in nature. The solar system is littered, however,
| with distorted polyhedra--shards of rock and ice produced by
| ubiquitous fragmentation. We apply the theory of convex mosaics
| to show that the average geometry of natural two-dimensional (2D)
| fragments, from mud cracks to Earth's tectonic plates, has two
| attractors: "Platonic" quadrangles and "Voronoi" hexagons. In
| three dimensions (3D), the Platonic attractor is dominant:
| Remarkably, the average shape of natural rock fragments is
| cuboid. When viewed through the lens of convex mosaics, natural
| fragments are indeed geometric shadows of Plato's forms.
| Simulations show that generic binary breakup drives all mosaics
| toward the Platonic attractor, explaining the ubiquity of cuboid
| averages. Deviations from binary fracture produce more exotic
| patterns that are genetically linked to the formative stress
| field. We compute the universal pattern generator establishing
| this link, for 2D and 3D fragmentation._
| mmooss wrote:
| Voronoi diagrams I see have few if any hexagons (use your
| favorite mathematical reference or image search). Is that idea
| that if the points are distributed equidistant in 'alternating'
| ranks [0], then the diagram is hexagons?
|
| Also, what is "binary breakup" and "binary fracture"?
|
| [0] Alternating ranks: I mean something like the following (is
| there a better name?): . . . . . .
| . . . . . . . . . . . . . .
| . . . .
| ducttapecrown wrote:
| The dots need to be the vertices of equilateral triangles for
| the Voronoi diagram to be hexagons, the above is a
| rectangular grid rotated 45 degrees.
|
| You can overlay a regular hexagonal tessellation over a
| regular triangular tessellation to see this.
| flqn wrote:
| In context, binary breakup and binary fracture apppear to
| mean a splitting ofa whole into two parts along a given line
| or plane
| emil-lp wrote:
| > Years ago, Domokos had won renown by proving the existence of
| the Gomboc, a curious three-dimensional shape that swivels into
| an upright resting position no matter how you push it.
|
| Some researchers are just incredible achievers.
| boi694206 wrote:
| yo bean headed ahhh needs to release a site like this but its
| really geometry dash NOW or else...
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(page generated 2026-01-05 23:01 UTC)