Can I Lick It?

At some point in human history, someone licked every element in #periodic table

Not the same person, obviously—that would require an impressive tolerance for radiation & poor decision-making

But collectively, across centuries of #scientific #inquiry, accidental exposure, & sheer #human stubbornness, tongues touched all 118 known elements

Some of those encounters went fine. Others ended careers, relationships & vital organ function.

https://fazzler.com/can-i-lick-it-a-periodic-table-for-the-curious-and-the-doomed/

#science #humour

@infobeautiful
The #older amongst us remember the figures you the when you feed different #periodic signals in the x- and y-deflection of an #Oscilloscope

Often seen in these #pictures from 1966

https://www.imdb.com/de/title/tt0061289/

A quick drawing of Kalium!
It's hard to think of ideas of what else to draw while I make my comic but the consistency helps 🌐
#originalcharacter #alkali #kalium #metal #oc #periodic #periodictable #scifi #simple #woman #yellow #yellowhair #elementeon #alkalimetal
On Periodic Tilings with Regular Polygons

I'm wondering: #physics makes a lot of use of #periodic functions, in particular it is very useful to solve space-dependent equations in representative volumes with #periodicBoundaryConditions.

However I've only seen it done with periodicity along orthogonal directions, aligned with a Cartesian frame.

Do you know of work, e.g. #PDE resolution, in nonrectangular #periodicDomains? E.g., in a #tiled hexagon? (but with a sufficiently generic setting, not exploiting regular hexagon symmetries) Even better if the periodicity parameters themselves are among the unknowns.

(Maybe I'm completely missing something obvious there, I'm in my first steps towards defining what I want - any random thought on the topic highly welcome!)

#tiling people?

The periodic table for spatial analysis, where each element of the table contains a set of explained spatial analysis tools, grouped by color and vector on the left and raster on the right #periodic

https://gisgeography.com/spatial-analysis-periodic-table/

The Periodic Table for Spatial Analysis - GIS Geography

The Periodic Table for Spatial Analysis lists 90 tools for quantifying, finding patterns, and predicting outcomes in a geographic context.

GIS Geography
#3StrandBraids

As I mentioned in https://pixelfed.social/p/Splines/797555432624206626, the geometry of braid strands is not at all obvious despite how familiar they look.

The geometry is defined in a series of steps starting with two coil-shaped #helix curves that we project on two perpendicular flat surfaces to create two flat #sinusoidal curves. Then, we transform the two flat sinusoids back into a composite 3D curve that acts as the rail for each strand. Then, we arrange three strands to form a braid. If you have never seen the geometry of a braid strand, you might be surprised at how it looks.

A braid strand is #periodic just like the #sinusoid curves it is based on. That means the pattern repeats at a fixed period and the motif can go on forever. For our purposes, a braid that is µ = 144 units long is sufficient, but to get that, we have to start with a helix that is longer than µ.

In the front view, start at the origin and draw a helix of length µ*4/3 = 192 units. This is shown in blue in the top-left portion of the figure. Directly underneath that is the view as seen from the top, which looks very similar to the one in the front view, but is distinct. Since a helix is like a round coil, it looks like a circle if viewed from a side as shown in bottom left. Only in the perspective view seen on the right is the coil shape readily apparent.

The blue helix has a fixed distance equal to 1/2 part (4 units) from the axis and it makes 8 full turns along the entire length of the axis, meaning it repeats with a period (or wavelength) of 192/8 = 24 units or 3 parts. This is crucial: For a 3 strand braid, the period must be a multiple of 3.

Duplicate the blue helix and double it in size while centered on the origin. Then, shift the larger helix by 1/4 of period (6 units) to the left. This larger helix is shown in magenta.

These helices are still in 3D. Make sure that the front, top, and right views look like what's shown here. Otherwise, the next step won't work.
Splines (@[email protected])

#3StrandBraids #Braids are the last of the #decorative elements on the #IonicScroll, but like #EggsAndDarts, they are not specific to the #IonicOrder. Braids are a popular design motif that find wide currency in modern #hairstyles, #fashion, and fashion accessories like #belts and #bracelets. Braids come in infinite varieties with varying number of strands, thickness of strands, roundness or flatness of strands, and how tightly or loosely they are wound together. Here, I focus on the 3-strand variant mentioned in #Vignola's book and previewed in https://pixelfed.social/p/Splines/792015485979791089. The image here is brightly colored to draw attention to the 3 strands. The geometry of braid strands is not at all obvious despite how familiar they look. Also, a braid strand is the only feature in the entire iconic order whose geometry cannot be captured with straight lines and circular arcs. Instead, a strand geometry must be defined in a series of steps starting with a basic #sinusoidal curve. A sinusoidal curve or #sinusoid is a wave form whose function belongs to a family of functions known as #transcendentalFunctions that also include #logarithmic and #exponential functions. I mentioned #logarithmicSpirals in https://pixelfed.social/p/Splines/792499765146596723, and in a future post I will show how to construct one and compare it with the #spiral used in our implementation of #IonicVolute. They are called transcendental functions because they transcend the math of finite algebraic polynomials and go beyond geometry into trigonometry. Fortunately, we don't have to go there. Few #CAD tools have a direct primitive for a sinusoid, but almost all have a primitive for a 3-dimensional round coil shape called a #helix which we can use to create the sinusoids we need for a braid strand. To create a sinusoid, all we need to do is #project a helix on a flat surface to convert it into a 2D waveform.

Pixelfed