Chemistry student here, I came across a curiosity in a thought

>>8079123
Space is not quantized.

>>8079123
>is there then a minimum angle unit

1 Planck length / diameter of the visible universe / 2π

>>8079123
>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.

>>8079133
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?

>>8079146
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.

>>8079146
man you have no idea what 'quantized' even means...

>>8080978
he's fucking asking, instead of trying to sound smart, come up with a proper response, idiot

>>8079146
>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.

>>8079146
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.

>>8079146
I still go by the notion that there's something traveling faster than light and we just haven't caught it yet.

File: dw-shade-queen-5-1440586596.jpg (51KB, 500x388px) Image search: [Google]

51KB, 500x388px

>>8081547

>>8080975
>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.

>>8080975
So if there is no minimum length does this mean that we can continue to make computers smaller?

>>8081595
Semi conductors begin to fail at being transistors at ~5nm

>>8081595
No, there's a minimum size things can be before they stop being reliable.

Space isn't quantised but matter sort of is.

I'm hijacking this a bit:

How do we know space isn't quantized?

>>8081608
Well we don't *know* a lot of things but there hasn't been any evidence to suggest that it is.

>>8081608
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

>>8081612
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.

>>8081618
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?

>>8081625
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.

>>8081608
>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.

>>8081625
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.

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.

>>8079133
>>8079133
I think he means phase space
Don't expect chemistry students to know the fundamentals of their own field

>>8081696
1) phase spaces were left in the dust along with classical mechanics
2) no he's not

>>8079123
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.

>>8081723
>what is the Heisenberg uncertainty principle?
Also, quantum can be formulated in phase space
Educate yourself

>>8081748
right, because OP knows all about Wigner functions

>>8081606
>but *order sort of is
indeed

>>8083792
>He bumped this thread almost 20 hours after the last bump to post this.

REEEEEEEEEE.

>>8083802
I am not OP. I closed my laptop with several tabs open.