It depends on where you draw the line (heh) on “straightness” and “flatness”. Some planes on gems or geodes are pretty flat, but probably not perfectly flat. Another example is a spider’s web between two points. That’s a pretty straight line if it’s taut, but again, probably not exactly perfect.
Do straight lines and flat planes exist in nature?
Submitted 8 months ago by bloom_of_rakes@lemm.ee to nostupidquestions@lemmy.world
Comments
Thavron@lemmy.ca 8 months ago
DarkThoughts@fedia.io 8 months ago
Nothing is perfectly flat, neither in nature nor man made. It's purely a mathematical concept as every surface has some form of texture if you look close enough.
Thavron@lemmy.ca 8 months ago
Well, yes. My point exactly.
Steve@startrek.website 8 months ago
Right, atoms are not flat
neptune@dmv.social 8 months ago
A string with weight will be a pulled under gravity. Yes even a taut spider web.
tobogganablaze@lemmus.org 8 months ago
Lines and planes in the mathematical sense are 1 and 2 dimensional. They don’t have any height (and lines also no width). So they can’t exist as a physical object (made out of atoms) as they are already 3 dimensional.
They only exist as a concept.
bloom_of_rakes@lemm.ee 8 months ago
Then, o pedant, do straight or flat objects (thus linelike, planelike) exist?
gedaliyah@lemmy.world 8 months ago
Why ask a pedantic question and be upset by a pedantic answer?
pennomi@lemmy.world 8 months ago
Graphene is a great example of a planar molecule, within 1 atom of tolerance.
inlandempire@jlai.lu 8 months ago
Their manifestation in our world was limited, they have already gone to another plane of existence
angrystego@lemmy.world 8 months ago
The fact that something isn’t a 3d object doesn’t mean it doesn’t exist. Does a line of contrast between 2 colors exist? Does a movie projected at a wall exist?
tobogganablaze@lemmus.org 8 months ago
Does a line of contrast between 2 colors exist?
I’d say no. And even if it did, those colours are made out of atoms or light, both of which are “fuzzy” and 3D and can’t make a proper line.
Does a movie projected at a wall exist?
Sure. There is photons bouncing of a wall and the information they carry we call “the movie”. I guess that counts. But the relevant bit is the wall and again it’s made out of atoms and there is not a proper flat 2D surface.
Paragone@lemmy.world 8 months ago
maybe somebody else pointed this out:
Light ALWAYS travels in its idea of a straight-line.
Always.
It doesn’t matter whether it is bent by gravity or refraction, from its perspective, it kept going straight.
Only an “outside viewer” sees any non-straight-line-ness being done, but the outside-viewer isn’t seeing the curved-space or the curved-refractive-index that the photon saw.
Klear@lemmy.world 8 months ago
Well, kinda, but the line the photon is contracted in its POV into a point. Whatever destination is has, it’s already there as far as it’s concerned. It doesn’t experience time given that it’s moving at the speed of light.
MeanEYE@lemmy.world 8 months ago
Short answer, depends on perspective. For example surface of perfectly still lake could be considered flat, but on macro level it follows curvature of the earth. But we still use water to level our buildings, because radius of a planet is so big. On microscopic level it’s anything but flat.
Someone else mentioned spider silk danging. It’s also another great example, but the same perspective clause applies. But usually crystals and some geological features tend to have flat features.
neptune@dmv.social 8 months ago
You really have to declare to what degree you are asking. You could take a very carefully grown crystal and define a plane based on its lattice structure. But the atoms are not all perfectly placed on the lattice once you zoom in far enough. There’s even gaps between the atoms! A “plane” of carbon looks more like a net to an observer on the scale of those atoms.
Is an electron a perfect sphere? Scientists probably thought so in 1900 but now ask a physicist and they will say “No, probably not”.
And yes, as others have stated, our space time is not perfectly Euclidean so that’s another level of uncertainty. How do you measure the small imperfections in a Euclidean model when actual space time isn’t Euclidean?
As a professor used to tell my class, there are no 0s.
gedaliyah@lemmy.world 8 months ago
No, they are mathematical constructs. Everything in nature is composed of matter and the like, so there are no perfectly straight lines or flat planes.
Even a beam of light curves and refracts as it interacts with matter and space over a long enough distance.
Blue_Morpho@lemmy.world 8 months ago
Light is going straight from it’s point of view . It is following the shortest path between two points. The transform from different reference frames is why we see it as curved.
But if that’s your definition, then there are no straight lines in mathematics either because you could transform the straight line from one system into a curved line in another system.
gedaliyah@lemmy.world 8 months ago
Yes, nature is not objective - it is relative. Mathematics is a discipline that is based around an *objective *framework. Lines and planes are mathematical constructs. Mathematics gives us an objective framework that can be used to model a natural world, but they are just models.
Some things are “line-like” or “plane-like,” in that modeling them as lines or planes is helpful to describe them. You can measure a distance “as the bird flies” because birds fly in lines compared to how humans travel along roads and paths. You can describe a dense, heavy, falling object as traveling in a straight line, because air resistance may be negligible over short distances.
A model is only useful insofar as it accurately represents reality. Lines and planes are mathematical constructs, and they may be incorporated into models that describe real things. “A beam of light crossing a room travels in a straight line” is probably a useful construct because the effects of gravity and refraction of the air are probably negligible for nearly all purposes. “The surface of a pond is a plane” is probably an acceptable model for a cartographer, since the height of ripples and the curvature of the earth are negligible at that scale.
The initial question was not “Do straight lines and flat planes model anything in nature,” but whether they exist in nature. They do not. They only exist in mathematics.
vrek@programming.dev 8 months ago
Unless the light is in a vacuum like space
ada@lemmy.blahaj.zone 8 months ago
Gravitational lensing would like a work
june@lemmy.world 8 months ago
Light bends in space all the time. Our sun has enough gravity to bend light.
Steve@startrek.website 8 months ago
Space is not empty
AlDente@sh.itjust.works 8 months ago
There is no perfect vacuum, even in deep space. In the space of our Solar System, there is on average 5 atoms in every cubic centimeter. In interstellar space, there is on average 1 atom every cubic centimeter. In intergalactic space, there is on average 1 atom every 100 cubic centimeters. It’s a gradient, but much like the perfectly straight lines and flat planes in the original question, perfect vacuum is a theoretical construct that is impossible to achieve in our reality.
yarr@feddit.nl 8 months ago
Depending on scale. Is the surface of the lake flat?
Once you experience true level you will never go back.
bloom_of_rakes@lemm.ee 8 months ago
True level must be like true symbols (like, in the idea that there are true names and words. Like a divine language).
If you have a true level or symbol then you have something, just as good as reality, but manipulable like language. The best of both worlds.
And even better, you need never leave the confines of the inside of your mind ever again. You can live, within your construct of perfect god-language, and interact with the world from there. Safe and powerful.
Spitzspot@lemmings.world 8 months ago
Neutrinos travel in a straight line.
Ranvier@sopuli.xyz 8 months ago
Unfortunately (fortunately?) the space they’re traveling through is curved. It was a good attempt though neutrinos.
jbrains@sh.itjust.works 8 months ago
Edwin A. Abbott has entered the chat…
Blue_Morpho@lemmy.world 8 months ago
It appears curved to us because we mathematically transformed the reference frame.
If you are allowed to transform your geometric space to say “no straight lines” then there are no straight lines in math either. Because you could perform a transform on the straight line into a curved geometry.
bloom_of_rakes@lemm.ee 8 months ago
Not to mention quantum fuzzing
NeoNachtwaechter@lemmy.world 8 months ago
The neutrino neither knows that nor does it care about it.
In it’s reality, the line remains perfectly straight.
Krudler@lemmy.world 8 months ago
They don’t, although they do not interact with other particles, they obey move as waves, like all other energy in the universe.
Blue_Morpho@lemmy.world 8 months ago
“I want to emphasize that light comes in this form-particles. It is very important to know that light behaves like particles, especially for those of you who have gone to school, where you were probably told something about light behaving like waves. I’m telling you the way it does behave- like particles.”
Richard Feynman, “QED The Strange Theory of Light and Matter.” Introduction, Page 15.
SPRUNT@lemmy.world 8 months ago
Cubed pyrite is one of my favorite examples of this.
AnarchistArtificer@slrpnk.net 8 months ago
That’s very cool, I see why you like it
sarchar@programming.dev 8 months ago
I think we’ve got enough evidence (proof?) that the universe is flat, and straight lines will continue straight forever and never intersect.
Whether there’s an actual thing that exists that does this? Dunno. Two parallel particles I guess?
MinusPi@yiffit.net 8 months ago
Wut? Spacetime is anything but flat.
webghost0101@sopuli.xyz 8 months ago
I am pretty sure we have no such evidence of the sort. Last i checked the universe being torus/donut shaped was still in the cards.
sarchar@programming.dev 8 months ago
Wikipedia, en.m.wikipedia.org/wiki/Shape_of_the_universe
“As of 2023 current observational evidence suggests that the observable universe is spatially flat with an unknown global structure.”
I don’t fully understand this stuff, so I dunno.
BleatingZombie@lemmy.world 8 months ago
Sorry. Straight parallel like never intersect
sarchar@programming.dev 8 months ago
Right, my bad.
NeoNachtwaechter@lemmy.world 8 months ago
A frozen lake.
A spider’s thread when it’s climbing downwards.
snf@lemmy.world 8 months ago
Aaaaactchhhually a frozen lake would follow the local curvature of the earth
NeoNachtwaechter@lemmy.world 8 months ago
Still it took >12h before someone started to discuss that :)
Sizzler@slrpnk.net 8 months ago
I’ll going to call you on that one. Surely gravity defines the surface of the lake, not local curvature.
Audalin@lemmy.world 8 months ago
According to mathematical platonism, yes.
Otherwise we have no idea. We have some models of physics, none perfectly describing our universe. We don’t know the structure of space, or the structure of time.
Even if we did: what would it mean for a line or a plane to exist? There could be equivalent descriptions of our universe, some including those as objects and some only as emergent properties.
LouNeko@lemmy.world 8 months ago
A lot of people talk about straightness and flatness as mathematical concepts. But I think OP means it in a technical sense, as in flat like your phone screen or straight as the edges of the screen but in nature. In this sense, flatness or straightness is defined as a finite number of measured points on a surface of which the coordinates all lie between 2 mathematicaly flat/straight parallel tolerance planes/lines. By that definition, depending on what a person would consider flat, say 0.002 mm between the planes/lines, there are definetly naturally occurring crystals that would pass that test.
Krudler@lemmy.world 8 months ago
Simple answer: no
adespoton@lemmy.ca 8 months ago
Is the Higgs Field a flat plane?
bloom_of_rakes@lemm.ee 8 months ago
Right after they mow, otherwise it’s rather fluffy.
finickydesert@lemmy.ml 8 months ago
Yes they do
addmen@lemm.ee 8 months ago
Yes.
nutsack@lemmy.world 8 months ago
Damn that was fast I was just going to link a picture of my ass
Cornucopiaofplenty@lemmy.world 8 months ago
Your mom’s what??
bloom_of_rakes@lemm.ee 8 months ago
When you zoom in on those pristine facets it looks like a gravel driveway
meekah@lemmy.world 8 months ago
I mean, if you zoom far enough, its just a few atoms floating around in mostly nothing.
Define “flat” and “straight”