The Planck units are a choice of natural units relevant to cosmology. They aren't the smallest or largest of anything. The Planck mass is roughly the same as that of a fruit fly.
In our current established theoretical framework, there is no reason to presume that either time or space are discrete, nor is there experimental evidence for it.
The Planck constant [Js] was introduced to find a way around the UV catastrophe. The Planck length [m] is defined as \sqrt{\frac{\hbar G}{c^3}}, where G is the gravitational constant and c the speed of light in vacuum.
The Planck length is the shortest measurable length, not the shortest possible length. We have no idea how we'd even go about measuring anything smaller, because we don't understand physics smaller than that. There could be stuff that's smaller, like even more elementary particles that build everything and determine the rules of the physics and particles that we do understand. Or maybe not. Maybe that's the smallest anything can be and there isn't further sub-Planck physics, or maybe it's just turtles all the way down.
uhm, so, this is just my uneducated ass talking, but i'm pretty sure that there's no particles that make up ordinary matter below the planck length
and i'm saying this because as you split stuff up, you kinda expect the mass of the constituent elements be smaller than the mass of the total. so if you have smaller mass, you have larger uncertainty. and i think when we talk about the "diameter" of subatomic particles, what we really mean, is the uncertainty of its wave function. and that ironically gets larger when you look at smaller particles.
Anything moving has an associated wavelength. If that wavelength is long enough, you can do the young's double slip experiment on it.
It was a few years ago, so the details are hazy. A scientific team accelerated a particularly small and sturdy bacteria fast enough that their speed produced a viable wavelength. They then sent the stream through 2 slits. They then captured the bacteria in aerogel (I think) to slow them back down.
Most didn't survive, but some both survived, and ended up somewhere they couldn't without interfering with themselves. They successfully reproduced afterwards. The debris also followed the classic ripple pattern of the experiment.
Basically, there is nothing special about "life" when it comes to quantum mechanical effects, other than it's on the big side.
Only 1 bacteria ever arrives. It's the probability wave that interferes with itself.
With the Young's double slit experiment, if you fire a single photon, you get a single photon arriving. It looks just like how a cannon ball flies. It's only when you let hundreds go (either collectively or individually) that the interference pattern appears.
The end pattern is the probability that the photon (or bacteria) arrives at any given point on the receiver screen.
But the interference pattern only turns up after multiple detections. Each detection is just a single point on a board.
This means that the bacteria are identical down to the atom. Feels bigger than bacteria can be pushed through the double slit experiment?
It's the smallest length that our current understanding of the universe will allow. Any distance smaller is immeasurable to us. To measure small things you need to be able to hit them with a photon and get a signal back; and the smaller you want to measure the higher energy that photon has to be. The planck length is the distance where the photon you are using to measure has so much energy comparable to the size that the energy density instantly creates a black hole, that swallows whatever you are trying to observe. Thus it is impossible for us to measure smaller than that distance. Things might absolutely exist at scales smaller than that, but the universe seems to lock them away from us.
33 Comments
IAmNorRealTakeYourMeds@lemmy.world · 59 pts · 72d
it's also the measurement for the shortest possible time span
but also the hottest possible temperature.
deranger@sh.itjust.works · 35 pts · 72d
Min-Max Planck
ItsMyVault101@piefed.social · 22 pts · 72d
aka Planckmaxing
Hadriscus@jlai.lu · 5 pts · 72d
so, carpentry
nullspace@lemmy.world · 3 pts · 71d
What do you get when you put a plankmaxxer on a plank?
anomnom@sh.itjust.works · 4 pts · 71d
Bored.
ItsMyVault101@piefed.social · 0 pts · 70d
you nailed that one
deranger@sh.itjust.works · 1 pts · 72d
JoeBigelow@lemmy.ca · 1 pts · 72d
Mad Max Plank
Hapankaali@lemmy.world · 6 pts · 72d
The Planck units are a choice of natural units relevant to cosmology. They aren't the smallest or largest of anything. The Planck mass is roughly the same as that of a fruit fly.
In our current established theoretical framework, there is no reason to presume that either time or space are discrete, nor is there experimental evidence for it.
IAmNorRealTakeYourMeds@lemmy.world · -3 pts · 72d
Planck distance is a fundamental unit, otherwise we get the ultraviolet catastrophe
Hapankaali@lemmy.world · 4 pts · 71d
The Planck constant [Js] was introduced to find a way around the UV catastrophe. The Planck length [m] is defined as \sqrt{\frac{\hbar G}{c^3}}, where G is the gravitational constant and c the speed of light in vacuum.
gandalf_der_12te@feddit.org · 1 pts · 71d
is there any proof for this? that there's nothing outside it
IAmNorRealTakeYourMeds@lemmy.world · 2 pts · 71d
planck time is just the time it takes for light to travel a Planck distance, and Planck temperature is just a planck distance wavelength.
not really proof, and more like derivate units.
treesquid@lemmy.world · 46 pts · 72d
The Planck length is the shortest measurable length, not the shortest possible length. We have no idea how we'd even go about measuring anything smaller, because we don't understand physics smaller than that. There could be stuff that's smaller, like even more elementary particles that build everything and determine the rules of the physics and particles that we do understand. Or maybe not. Maybe that's the smallest anything can be and there isn't further sub-Planck physics, or maybe it's just turtles all the way down.
TypFaffke@feddit.org · 9 pts · 71d
We'll have to wait for the sub-Planck DLC to drop
gandalf_der_12te@feddit.org · 5 pts · 71d
uhm, so, this is just my uneducated ass talking, but i'm pretty sure that there's no particles that make up ordinary matter below the planck length
and i'm saying this because as you split stuff up, you kinda expect the mass of the constituent elements be smaller than the mass of the total. so if you have smaller mass, you have larger uncertainty. and i think when we talk about the "diameter" of subatomic particles, what we really mean, is the uncertainty of its wave function. and that ironically gets larger when you look at smaller particles.
LovableSidekick@lemmy.world · 31 pts · 71d
Max length would have been hella confusing.
troglodytis@lemmy.world · 16 pts · 72d
Dude set out to show it was all bullshit and figured out one of the most important pieces of the pie. Mission failed successfully
bjoern_tantau@swg-empire.de · 10 pts · 71d
Kind of like Schrödinger who wanted to ridicule quantum mechanics interpretations with his cat in a box. And now it's a famous analogy.
cynar@lemmy.world · 5 pts · 71d
They have also experimentally tested an equivalent experiment with bacteria. They survived a trip through the double slit experiment.
There doesn't seem to be an issue with it, other than it's difficult and impractical.
wibble@reddthat.com · 5 pts · 71d
Wait. What?
cynar@lemmy.world · 7 pts · 71d
Anything moving has an associated wavelength. If that wavelength is long enough, you can do the young's double slip experiment on it.
It was a few years ago, so the details are hazy. A scientific team accelerated a particularly small and sturdy bacteria fast enough that their speed produced a viable wavelength. They then sent the stream through 2 slits. They then captured the bacteria in aerogel (I think) to slow them back down.
Most didn't survive, but some both survived, and ended up somewhere they couldn't without interfering with themselves. They successfully reproduced afterwards. The debris also followed the classic ripple pattern of the experiment.
Basically, there is nothing special about "life" when it comes to quantum mechanical effects, other than it's on the big side.
wibble@reddthat.com · 4 pts · 71d
So. Something something duplicate an existing life form like a quantum photocopier? Or, what does the interference pattern of a bacteria looks like?
cynar@lemmy.world · 2 pts · 71d
Only 1 bacteria ever arrives. It's the probability wave that interferes with itself.
With the Young's double slit experiment, if you fire a single photon, you get a single photon arriving. It looks just like how a cannon ball flies. It's only when you let hundreds go (either collectively or individually) that the interference pattern appears.
The end pattern is the probability that the photon (or bacteria) arrives at any given point on the receiver screen.
wibble@reddthat.com · 1 pts · 71d
But the interference pattern only turns up after multiple detections. Each detection is just a single point on a board. This means that the bacteria are identical down to the atom. Feels bigger than bacteria can be pushed through the double slit experiment?
blarghly@lemmy.world · 5 pts · 71d
#science
Sylence@lemmy.dbzer0.com · 7 pts · 72d
Get Mercked idiot
gandalf_der_12te@feddit.org · 4 pts · 71d
is there any proof of it being the smallest length? i see that thrown around a lot but no proof for it. why wouldn't there be smaller lengths?
SpacetimeMachine@lemmy.world · 6 pts · 70d
It's the smallest length that our current understanding of the universe will allow. Any distance smaller is immeasurable to us. To measure small things you need to be able to hit them with a photon and get a signal back; and the smaller you want to measure the higher energy that photon has to be. The planck length is the distance where the photon you are using to measure has so much energy comparable to the size that the energy density instantly creates a black hole, that swallows whatever you are trying to observe. Thus it is impossible for us to measure smaller than that distance. Things might absolutely exist at scales smaller than that, but the universe seems to lock them away from us.
gandalf_der_12te@feddit.org · 1 pts · 70d
https://en.wikipedia.org/wiki/Planck_units#Planck_length
seems correct, as far as i can tell.
NerdyTimesOrWhatever@lemmy.today · 1 pts · 71d
iatenine@piefed.social · 3 pts · 71d
Explains how both of their surnames entered the lexicon
SubArcticTundra@lemmy.ml · 2 pts · 72d
Should have called it the Marie length to have it for herself