The complex geometry of Islamic design - Eric Broug

3,350,359 views ใƒป 2015-05-14

TED-Ed


ืื ื ืœื—ืฅ ืคืขืžื™ื™ื ืขืœ ื”ื›ืชื•ื‘ื™ื•ืช ื‘ืื ื’ืœื™ืช ืœืžื˜ื” ื›ื“ื™ ืœื”ืคืขื™ืœ ืืช ื”ืกืจื˜ื•ืŸ.

ืชืจื’ื•ื: Ido Dekkers ืขืจื™ื›ื”: Tal Dekkers
00:06
In Islamic culture, geometry is everywhere.
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ื‘ืชืจื‘ื•ืช ื”ืื™ืกืœืžื™ืช, ื’ืื•ืžื˜ืจื™ื” ื ืžืฆืืช ื‘ื›ืœ ืžืงื•ื.
00:10
You can find it in mosques, madrasas, palaces and private homes.
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ืืชื ื™ื›ื•ืœื™ื ืœืžืฆื•ื ืื•ืชื” ื‘ืžืกื’ื“ื™ื, ืžื“ืจืกื•ืช, ืืจืžื•ื ื•ืช ื•ื‘ืชื™ื ืคืจื˜ื™ื™ื.
00:16
This tradition began in the 8th century CE during the early history of Islam,
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ื”ืžืกื•ืจืช ื”ื–ื• ื”ื—ืœื” ื‘ืžืื” ื” 8 ืœืกืคื™ืจื” ื‘ืžื”ืœืš ื”ื”ืกื˜ื•ืจื™ื” ื”ืžื•ืงื“ืžืช ืฉืœ ื”ืื™ืกืœืื,
00:22
when craftsmen took preexisting motifs from Roman and Persian cultures
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ื›ืฉืืžื ื™ื ืœืงื—ื• ืžื•ื˜ื™ื‘ื™ื ืงื™ื™ืžื™ื ืžืชืจื‘ื•ื™ื•ืช ืจื•ืžืื™ื•ืช ื•ืคืจืกื™ื•ืช,
00:26
and developed them into new forms of visual expression.
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ื•ืคื™ืชื—ื• ืื•ืชืŸ ืœืฆื•ืจื•ืช ื—ื“ืฉื•ืช ืฉืœ ื”ื‘ืขื” ื•ื™ื–ื•ืืœื™ืช.
00:31
This period of history was a golden age of Islamic culture,
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ื”ืชืงื•ืคื” ื”ื–ื• ื‘ื”ืกื˜ื•ืจื™ื” ื”ื™ืชื” ื“ื•ืจ ื”ื–ื”ื‘ ืฉืœ ื”ืชืจื‘ื•ืช ื”ืื™ืกืœืžื™ืช,
00:35
during which many achievements of previous civilizations
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ืฉื‘ืžื”ืœื›ื” ื”ืจื‘ื” ื”ืฉื’ื™ื ืฉืœ ืชืจื‘ื•ื™ื•ืช ืงื•ื“ืžื•ืช
00:38
were preserved and further developed,
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ื ืฉืžืจื• ื•ื”ืชืคืชื—ื• ื”ืœืื”,
00:40
resulting in fundamental advancements in scientific study and mathematics.
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ืžื” ืฉื”ื‘ื™ื ืœื”ืชืงื“ืžื•ื™ื•ืช ืžืฉืžืขื•ืชื™ื•ืช ื‘ืžื—ืงืจื™ื ืžื“ืขื™ื™ื ื•ืžืชืžื˜ื™ืงื”.
00:46
Accompanying this was an increasingly sophisticated use of abstraction
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ื™ื—ื“ ืขื ื–ื” ื”ื™ื” ืฉื™ืžื•ืฉ ื’ื•ื‘ืจ ื‘ืคื™ืฉื•ื˜
00:50
and complex geometry in Islamic art,
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ื•ื’ืื•ืžื˜ืจื™ื” ืžื•ืจื›ื‘ืช ื‘ืืžื ื•ืช ื”ืืกืœืžื™ืช,
00:53
from intricate floral motifs adorning carpets and textiles,
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ืžืžื•ื˜ื™ื‘ื™ื ืคืจื—ื•ื ื™ื™ื ืžื•ืจื›ื‘ื™ื ืฉืžืงืฉื˜ื™ื ืฉื˜ื™ื—ื™ื ื•ื‘ื“ื™ื,
00:57
to patterns of tilework that seemed to repeat infinitely,
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ืœื“ื•ื’ืžืื•ืช ืฉืœ ืืจื™ื—ื™ื ืฉื ืจืื•ืช ืฉื—ื•ื–ืจื•ืช ืื™ืŸ ืกื•ืคื™ืช,
01:01
inspiring wonder and contemplation of eternal order.
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ื ื•ืชื ื™ื ื”ืฉืจืื” ืœืคืœื™ืื” ื•ื”ืจื”ื•ืจ ืฉืœ ืกื“ืจ ืื™ืŸ ืกื•ืคื™.
01:06
Despite the remarkable complexity of these designs,
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ืœืžืจื•ืช ื”ืžื•ืจื›ื‘ื•ืช ื™ื•ืฆืืช ื”ื“ื•ืคืŸ ืฉืœ ื”ืขื™ืฆื•ื‘ื™ื ื”ืืœื”,
01:09
they can be created with just a compass to draw circles
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ื”ื ื™ื›ื•ืœื™ื ืœื”ื•ื•ืฆืจ ืจืง ืขื ืžื—ื•ื’ื” ื›ื“ื™ ืœืฆื™ื™ืจ ืžืขื’ืœื™ื
01:12
and a ruler to make lines within them.
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ื•ืกืจื’ืœ ื›ื“ื™ ืœื™ืฆื•ืจ ืงื•ื•ื™ื ื‘ืชื•ื›ื,
01:14
And from these simple tools emerges a kaleidoscope multiplicity of patterns.
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ื•ืžื”ื›ืœื™ื ื”ืคืฉื•ื˜ื™ื ื”ืืœื” ืขื•ืœื” ืงืœื™ื™ื“ื•ืกืงื•ืค ืฉืœ ืžื›ืคืœื•ืช ืฉืœ ื“ื•ื’ืžืื•ืช.
01:20
So how does that work?
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ืื– ืื™ืš ื–ื” ืขื•ื‘ื“?
01:22
Well, everything starts with a circle.
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ื•ื‘ื›ืŸ, ื”ื›ืœ ืžืชื—ื™ืœ ืขื ืขื™ื’ื•ืœ.
01:25
The first major decision is how will you divide it up?
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ื”ื”ื—ืœื˜ื” ื”ืขื™ืงืจื™ืช ื”ืจืืฉื•ื ื” ื”ื™ื ืื™ืš ืชื—ืœืงื• ืื•ืชื•?
01:28
Most patterns split the circle into four, five or six equal sections.
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ืจื•ื‘ ื”ื“ื•ื’ืžืื•ืช ืžื—ืœืงื•ืช ืืช ื”ืขื™ื’ื•ืœ ืœืืจื‘ืขื”, ื—ืžื™ืฉื” ืขื• ืฉื™ืฉื” ื—ืœืงื™ื ืฉื•ื•ื™ื.
01:34
And each division gives rise to distinctive patterns.
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ื•ื›ืœ ื—ืœื•ืงื” ืžืขืœื” ื“ื•ื’ืžืื•ืช ื™ื—ื•ื“ื™ื•ืช.
01:37
There's an easy way to determine whether any pattern is based on fourfold,
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ื™ืฉ ื“ืจืš ืคืฉื•ื˜ื” ืœืงื‘ื•ืข ืื ื›ืœ ื“ื•ื’ืžื” ืžื‘ื•ืกืกืช ืขืœ ืžื›ืคืœื” ื’ืื•ืžื˜ืจื™ืช ืฉืœ ืืจื‘ืข,
01:41
fivefold,
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ื—ืžืฉ,
01:43
or sixfold symmetry.
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ืื• ืฉืฉ.
01:45
Most contain stars surrounded by petal shapes.
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ืจื•ื‘ืŸ ืžื›ื™ืœื•ืช ื›ื•ื›ื‘ื™ื ืฉืžื•ืงืคื™ื ืขืœ ื™ื“ื™ ืฆื•ืจื•ืช ืฉืœ ืขืœื™ ื›ื•ืชืจืช.
01:48
Counting the number of rays on a starburst,
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ืกืคื™ืจืช ืžืกืคืจ ื”ืงืจื ื™ื™ื ืขืœ ืžืงื•ืจ ืื•ืจ,
01:51
or the number of petals around it,
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ืื• ืžืกืคืจ ืขืœื™ ื”ื›ื•ืชืจืช ืกื‘ื™ื‘ื•,
01:53
tells us what category the pattern falls into.
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ืžืกืคืจ ืœื ื• ืœืื™ื–ื” ืงื˜ื’ื•ืจื™ื” ื”ืฆื•ืจื” ืฉื™ื™ื›ืช.
01:56
A star with six rays, or surrounded by six petals,
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ื›ื•ื›ื‘ ืขื ืฉืฉ ืงืจื ื™ื™ื, ืื• ืžื•ืงืฃ ื‘ืฉื™ืฉื” ืขืœื™ ื›ื•ืชืจืช,
02:00
belongs in the sixfold category.
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ืฉื™ื™ืš ืœืžืฉืคื—ืช ื”ืžื›ืคืœื” ื”ืžืฉื•ืฉื”.
02:03
One with eight petals is part of the fourfold category, and so on.
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ืื—ื“ ืขื ืฉืžื•ื ื” ืขืœื™ ื›ื•ืชืจืช ื”ื•ื ื—ืœืง ืžื”ืงื˜ื’ื•ืจื™ื•ืช ืฉืœ ืžื›ืคืœืช ื”ืืจื‘ืข, ื•ื›ืš ื”ืœืื”.
02:08
There's another secret ingredient in these designs:
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ื™ืฉ ืžืจื›ื™ื‘ ืกื•ื“ื™ ื ื•ืกืฃ ื‘ืขื™ืฆื•ื‘ื™ื ื”ืืœื”:
02:11
an underlying grid.
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ื’ืจื™ื“ ื‘ื‘ืกื™ืกื•.
02:13
Invisible, but essential to every pattern,
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ื‘ืœืชื™ ื ืจืื”, ืื‘ืœ ื—ื™ื•ื ื™ ืœื›ืœ ื“ื•ื’ืžื”,
02:16
the grid helps determine the scale of the composition before work begins,
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ื”ื’ืจื™ื“ ืขื•ื–ืจ ืœืงื‘ื•ืข ืืช ืงื ื” ื”ืžื™ื“ื” ืฉืœ ื”ืงื•ืžืคื•ื–ื™ืฆื™ื” ืœืคื ื™ ืฉื”ืขื‘ื•ื“ื” ืžืชื—ื™ืœื”,
02:21
keeps the pattern accurate,
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ืฉื•ืžืจ ืขืœ ื”ื“ื•ื’ืžื” ืžื“ื•ื™ื™ืงืช,
02:22
and facilitates the invention of incredible new patterns.
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ื•ืžืืคืฉืจ ื”ืžืฆืื” ืฉืœ ื“ื•ื’ืžืื•ืช ื—ื“ืฉื•ืช ื•ื ืคืœืื•ืช.
02:26
Let's look at an example of how these elements come together.
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ื‘ื•ืื• ื ื‘ื™ื˜ ื‘ื“ื•ื’ืžื” ืฉืœ ืื™ืš ื”ืืœืžื ื˜ื™ื ื”ืืœื” ืžืชื—ื‘ืจื™ื.
02:30
We'll start with a circle within a square, and divide it into eight equal parts.
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ื ืชื—ื™ืœ ืขื ืขื™ื’ื•ืœ ื‘ืชื•ืš ืžืจื•ื‘ืข, ื•ื ื—ืœืง ืื•ืชื• ืœืฉืžื•ื ื” ื—ืœืงื™ื ืฉื•ื•ื™ื.
02:35
We can then draw a pair of criss-crossing lines
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ืื ื—ื ื• ื™ื›ื•ืœื™ื ืื– ืœืฆื™ื™ืจ ื–ื•ื’ ืงื•ื™ื ืืœื›ืกื•ื ื™ื™ื
02:39
and overlay them with another two.
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ื•ืžืขืœื™ื”ื ืขื•ื“ ืฉื ื™ื™ื.
02:41
These lines are called construction lines,
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ื”ืงื•ื•ื™ื ื”ืœืื” ื ืงืจืื™ื ืงื•ื•ื™ ื‘ื ื™ื”,
02:44
and by choosing a set of their segments,
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ื•ืขืœ ื“ื™ ื‘ื—ื™ืจื” ืฉืœ ืกื˜ ืฉืœ ื”ืžืงื˜ืขื™ื ืฉืœื”ื,
02:46
we'll form the basis of our repeating pattern.
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ื ื™ืฆื•ืจ ืืช ื”ื‘ืกื™ืก ืฉืœ ื”ื“ื•ื’ืžื” ื”ื—ื•ื–ืจืช ืฉืœื ื•.
02:50
Many different designs are possible from the same construction lines
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ืขื™ืฆื•ื‘ื™ื ืฉื•ื ื™ื ืจื‘ื™ื ืืคืฉืจื™ื™ื ืžืื•ืชื ืงื•ื•ื™ ื‘ื ื™ื”
02:54
just by picking different segments.
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ืจืง ืขืœ ื™ื“ื™ ื‘ื—ื™ืจื” ืฉืœ ืžืงื˜ืขื™ื ืฉื•ื ื™ื.
02:57
And the full pattern finally emerges
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ื•ื”ื“ื•ื’ืžื” ื”ื›ืœืœื™ืช ืœื‘ืกื•ืฃ ืžื•ืคื™ืขื”
02:59
when we create a grid with many repetitions of this one tile
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ื›ืฉืื ื—ื ื• ื™ื•ืฆืจื™ื ื’ืจื™ื“ ืขื ื”ืจื‘ื” ื—ื–ืจื•ืช ืฉืœ ื”ืืจื™ื— ื”ื™ื—ื™ื“ ื”ื–ื”
03:04
in a process called tessellation.
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ื‘ืชื”ืœื™ืš ืฉื ืงืจื ืฉื™ื‘ื•ืฅ ื‘ืคืกื™ืคืก.
03:07
By choosing a different set of construction lines,
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ืขืœ ื™ื“ื™ ื‘ื—ื™ืจื” ืฉืœ ืกื˜ ืฉื•ื ื” ืฉืœ ืงื•ื™ ื‘ื ื™ื™ืŸ,
03:09
we might have created this pattern,
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ืื ื—ื ื• ืื•ืœื™ ื ื™ืฆื•ืจ ืืช ื”ื“ื•ื’ืžื” ื”ื–ื•,
03:12
or this one.
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ืื• ืืช ื–ื•.
03:14
The possibilities are virtually endless.
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ื”ืืคืฉืจื•ื™ื•ืช ื”ืŸ ืžืžืฉ ืื™ืŸ ืกื•ืคื™ื•ืช.
03:17
We can follow the same steps to create sixfold patterns
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ืื ื—ื ื• ื™ื›ื•ืœื™ื ืœืขืงื•ื‘ ืขื›ืฉื™ื• ืื—ืจื™ ืื•ืชื ืฉืœื‘ื™ื ื›ื“ื™ ืœื™ืฆื•ืจ ื“ื•ื’ืžื” ืฉืœ ืžื›ืคืœืช ืฉืฉ
03:21
by drawing construction lines over a circle divided into six parts,
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ืขืœ ื™ื“ื™ ืฆื™ื•ืจ ืฉืœ ืงื•ื™ ื‘ื ื™ื” ืขืœ ืžืขื’ืœ ืฉืžื—ื•ืœืง ืœืฉื™ืฉื” ื—ืœืงื™ื,
03:25
and then tessellating it, we can make something like this.
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ื•ืื– ืขื•ืฉื™ื ืคืกื™ืคืก ืฉืœื•, ืื ื—ื ื• ื™ื›ื•ืœื™ื ืœื™ืฆืจ ืžืฉื”ื• ื›ืžื• ื–ื”.
03:29
Here's another sixfold pattern that has appeared across the centuries
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ื”ื ื” ื“ื•ื’ืžื” ืžืฉื•ืฉื” ื ื•ืกืคืช ืฉื”ื•ืคื™ืขื” ืœืื•ืจืš ืžืื•ืช ื”ืฉื ื™ื
03:33
and all over the Islamic world,
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ื•ื‘ื›ืœ ืจื—ื‘ื™ ื”ืขื•ืœื ื”ืื™ืกืœืžื™,
03:35
including Marrakesh, Agra, Konya and the Alhambra.
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ื›ื•ืœืœ ืžืจืงืฉ, ืื’ืจื”, ืงื•ื ื™ื” ื•ื”ืืœื”ืžื‘ืจื”.
03:41
Fourfold patterns fit in a square grid, and sixfold patterns in a hexagonal grid.
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ื“ื•ื’ืžืื•ืช ืžืจื•ื‘ืขื•ืช ืžืชืื™ืžื•ืช ืœื’ืจื™ื“ ืžืจื•ื‘ืข, ื•ื“ื•ื’ืžืื•ืช ืžืฉื•ืฉื•ืช ื‘ื’ืจื™ื“ ืžืฉื•ืฉื”.
03:49
Fivefold patterns, however, are more challenging to tessellate
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ื“ื•ื’ืžืื•ืช ืžื—ื•ืžืฉื•ืช ืขื ื–ืืช, ื”ืŸ ื™ื•ืชืจ ืžื•ืจื›ื‘ื•ืช ืœืคืกื™ืคืก
03:53
because pentagons don't neatly fill a surface,
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ืžืคื ื™ ืฉืžื—ื•ืžืฉื™ื ืœื ืžืžืœืื™ื ืืช ื”ืฉื˜ื— ื‘ืฆื•ืจื” ืฉืœืžื”,
03:57
so instead of just creating a pattern in a pentagon,
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ืื– ื‘ืžืงื•ื ืœื™ืฆื•ืจ ื“ื•ื’ืžื” ื‘ืžื—ื•ืžืฉ,
04:00
other shapes have to be added to make something that is repeatable,
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ืฆื•ืจื•ืช ืื—ืจื•ืช ื—ื™ื™ื‘ื•ืช ืœื”ื™ื•ืช ืžื•ืกืคื•ืช ื›ื“ื™ ืœื™ืฆื•ืจ ืžืฉื”ื• ืฉื—ื•ื–ืจ ืขืœ ืขืฆืžื•,
04:04
resulting in patterns that may seem confoundingly complex,
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ื•ื”ืชื•ืฆืื” ื”ื™ื ื“ื•ื’ืžืื•ืช ืฉืื•ืœื™ ื ืจืื•ืช ืžื•ืจื›ื‘ื•ืช ื‘ื™ื•ืชืจ,
04:08
but are still relatively simple to create.
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ืื‘ืœ ืขื“ื™ื™ืŸ ื™ื—ืกื™ืช ืคืฉื•ื˜ื•ืช ืœื™ืฆื™ืจื”.
04:11
Also, tessellation is not constrained to simple geometric shapes,
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ื›ืžื• ื›ืŸ, ืคืกื™ืคืก ืœื ืžื•ื’ื‘ืœ ืœืฆื•ืจื•ืช ื’ืื•ืžื˜ืจื™ื•ืช ืคืฉื•ื˜ื•ืช,
04:16
as M.C. Escher's work demonstrates.
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ื›ืžื• ืฉื”ืขื‘ื•ื“ื•ืช ืฉืœ MC ืืฉืจ ืžื“ื’ื™ืžื•ืช.
04:19
And while the Islamic geometric design tradition
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ื•ื‘ืขื•ื“ ื”ืขื™ืฆื•ื‘ ื”ื’ืื•ืžื˜ืจื™ ื”ืžืกื•ืจืชื™ ื”ืื™ืกืœืžื™
04:22
doesn't tend to employ elements like fish and faces,
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ืœื ื ื•ื˜ื” ืœื”ืฉืชืžืฉ ื‘ืืœืžื ื˜ื™ื ื›ืžื• ื“ื’ื™ื ื•ืคืจืฆื•ืคื™ื,
04:25
it does sometimes make use of multiple shapes to craft complex patterns.
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ื”ื•ื ื›ืŸ ืœืขื™ืชื™ื ืžืฉืชืžืฉ ื‘ืžืกืคืจ ืฆื•ืจื•ืช ื›ื“ื™ ืœื™ืฆื•ืจ ื“ื•ื’ืžืื•ืช ืžื•ืจื›ื‘ื•ืช.
04:31
This more than 1,000-year-old tradition has wielded basic geometry
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ื”ืžืกื•ืจืช ื”ื–ื• ื‘ืช ื™ื•ืชืจ ืž 1,000 ืฉื ื” ื”ืฉืชืžืฉื” ื‘ื’ืื•ืžื˜ืจื™ื” ื‘ืกื™ืกื™ืช
04:36
to produce works that are intricate, decorative and pleasing to the eye.
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ื›ื“ื™ ืœื™ื™ืฆืจ ืขื‘ื•ื“ื•ืช ืžื•ืจื›ื‘ื•ืช, ื“ืงื•ืจื˜ื™ื‘ื™ื•ืช, ื•ื ืขื™ืžื•ืช ืœืขื™ืŸ.
04:41
And these craftsmen prove just how much is possible
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ื•ื”ืืžื ื™ื ื”ืืœื” ื”ื•ื›ื™ื—ื• ื›ืžื” ืืคืฉืจื™
04:44
with some artistic intuition, creativity, dedication and a great compass and ruler.
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ืขื ืื™ื˜ื•ืื™ืฆื™ื” ืืžื ื•ืชื™ืช, ื™ืฆื™ืจืชื™ื•ืช, ืžืกื™ืจื•ืช ื•ืžื—ื•ื’ื” ื•ืกืจื’ืœ ื˜ื•ื‘ื™ื.
ืขืœ ืืชืจ ื–ื”

ืืชืจ ื–ื” ื™ืฆื™ื’ ื‘ืคื ื™ื›ื ืกืจื˜ื•ื ื™ YouTube ื”ืžื•ืขื™ืœื™ื ืœืœื™ืžื•ื“ ืื ื’ืœื™ืช. ืชื•ื›ืœื• ืœืจืื•ืช ืฉื™ืขื•ืจื™ ืื ื’ืœื™ืช ื”ืžื•ืขื‘ืจื™ื ืขืœ ื™ื“ื™ ืžื•ืจื™ื ืžื”ืฉื•ืจื” ื”ืจืืฉื•ื ื” ืžืจื—ื‘ื™ ื”ืขื•ืœื. ืœื—ืฅ ืคืขืžื™ื™ื ืขืœ ื”ื›ืชื•ื‘ื™ื•ืช ื‘ืื ื’ืœื™ืช ื”ืžื•ืฆื’ื•ืช ื‘ื›ืœ ื“ืฃ ื•ื™ื“ืื• ื›ื“ื™ ืœื”ืคืขื™ืœ ืืช ื”ืกืจื˜ื•ืŸ ืžืฉื. ื”ื›ืชื•ื‘ื™ื•ืช ื’ื•ืœืœื•ืช ื‘ืกื ื›ืจื•ืŸ ืขื ื”ืคืขืœืช ื”ื•ื•ื™ื“ืื•. ืื ื™ืฉ ืœืš ื”ืขืจื•ืช ืื• ื‘ืงืฉื•ืช, ืื ื ืฆื•ืจ ืื™ืชื ื• ืงืฉืจ ื‘ืืžืฆืขื•ืช ื˜ื•ืคืก ื™ืฆื™ืจืช ืงืฉืจ ื–ื”.

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