Chemistry student here, I came across a curiosity in a thought today that I'm wondering if any of you guys know about.
I've only really dealt with quantum mechanics with regards to electron density probabilities and the like, but I get the basis of it, with that space itself is quantized. But, given that space is quantized, and there's a minimal 'unit' of reality, is there then a minimum angle unit? I mean obviously a perfect sphere is impossible to materially produce, given that the units of material are discrete, but thinking about how in a crystal structure we represent atoms as spherical, I'm wondering if that's true or if there's a more accurate expression out there based on the planck to describe the closest thing you can get to a sphere.
I tried googling, but didn't find anything, as I'm not sure what to search for.
Pic semi-related
Mason Parker
Space is not quantized.
Lincoln Sanders
>is there then a minimum angle unit
1 Planck length / diameter of the visible universe / 2π
Samuel Martinez
>given that space is quantized It's not. I'm guessing that you're referring to the Planck length, but that doesn't imply that there's a "minimum distance", in fact the Planck length has no physical relevance.
Jason Rivera
I thought it's quantized based on the speed of light, given that light isn't necessarily the fastest thing in the universe, rather there's a maximum speed in the universe and light is at max?
Dylan Morris
We still consider space and time to be continuous.. Quantising space and time is some people have tried doing to unify GR and QM. You might be thinking of Planck length, but this is the minimum observable length, rather than the minimum possible length.
Austin Hall
man you have no idea what 'quantized' even means...
Julian Price
he's fucking asking, instead of trying to sound smart, come up with a proper response, idiot
Caleb Adams
>I thought it's quantized based on the speed of light, given that light isn't necessarily the fastest thing in the universe, rather there's a maximum speed in the universe and light is at max? You thought wrong.
Jaxon Powell
Space is not quantized, or split into definable "quantities". Imagine a 3D grid, imaginary lines every how many units you decide. Imagine over time, this grid gets larger, so any 2 points that were once close, are now farther apart. That's space. There's always smaller segments of space. Space is arbitrarily large in this universe, and getting arbitrarily larger to infinity.
Adrian Price
I still go by the notion that there's something traveling faster than light and we just haven't caught it yet.
Ethan Williams
...
Sebastian Morales
>but this is the minimum observable length, rather than the minimum possible length. It's not even that, it's within about a factor of 10 as the smallest measurable length but it's not related.
Josiah Hughes
So if there is no minimum length does this mean that we can continue to make computers smaller?
Adam Hill
Semi conductors begin to fail at being transistors at ~5nm
Zachary Sullivan
No, there's a minimum size things can be before they stop being reliable.
Space isn't quantised but matter sort of is.
Elijah Taylor
I'm hijacking this a bit:
How do we know space isn't quantized?
Christopher Davis
Well we don't *know* a lot of things but there hasn't been any evidence to suggest that it is.
Henry Walker
Space "could" be quantised but at the level of observation it isn't. A bit like why you don't worry about Debroglies wavelength when a Lorry goes through a tunnel
Josiah Brown
And there's no evidence to suggest it isn't.
I'm just saying, as a condensed matter theorist, quantized space makes a whole lot of sense to me - and naively it seems to solve some problems.
A lot of people being kinda confident in this thread if we don't really have evidence one way or the other.
David Baker
Yeah so it's kind of up to people who propose the idea to come up with good reasons for it since non quantised space is working pretty well at the moment. One might argue that the discussion is pointless at the current time because any minimum length scale is far smaller than what is currently workable in experiment.
What problems do you think it would solve?
Jonathan Murphy
WELL okay, first to answer OP's question:
When drawing crystal structures, we often draw the atoms as spherical, because it's a relatively useful way to draw the pictures. Mostly when you fist start learning about these things, you worry about crystal structures of simple metals, where the bonding isn't so direction dependent, and the lowest energy structures happen to be very similar to the way that spheres pack together. BUT, in reality the shapes of the electron clouds around the atoms can be distorted, so they don't look like spheres at all. And this happens very commonly. So there are already corrections to the picture even not considering that space might be quantized on a very very very small length scale.
Robert Sullivan
>How do we know space isn't quantized? We don't. But the most successful theory that says our spacetime is quantized is LQG. I think that speaks for itself.
Adrian Jenkins
Now, my naive understanding is that the problem of marrying GR and QM occurs due to divergences obtained at high energy (continuum limit). Having a discrete space would give a natural high energy cutoff, so you couldn't have real divergences.
Carter Evans
OP, space is not actually quantized. We assume that space and time are continuous for most maths. But there is a lower bound on the smallest /measurable/ distance, which is the Planck length, ~[math]1.6 * 10^{-35}[/math] m.
Logan Peterson
I think he means phase space Don't expect chemistry students to know the fundamentals of their own field
Jeremiah Diaz
1) phase spaces were left in the dust along with classical mechanics 2) no he's not
John Gutierrez
When the size of the structure is significantly larger than the size of atoms, you can treat the atoms as point like. In that respect, we have defined a criteria for needed accuracy.
If you're asking about how close we can physically get, then you can look at some mat Sci projects like the blackest object.
Andrew Butler
>what is the Heisenberg uncertainty principle? Also, quantum can be formulated in phase space Educate yourself
Carson Fisher
right, because OP knows all about Wigner functions
Andrew James
>but *order sort of is indeed
Ayden Gomez
>He bumped this thread almost 20 hours after the last bump to post this.
REEEEEEEEEE.
Jayden Sullivan
I am not OP. I closed my laptop with several tabs open.