>>17016986
Previous thread: >>16944314

>>17016986
I have one. If the double slit interference is an optical phenomenon where light waves pass through two closely spaced slits and overlap, creating an alternating pattern of bright and dark bands (fringes) on a screen. What would happen to the bands if you sent a single photon through, then waited some time (Like a day) before firing another one through. Would the inference band show signs of slight deformation to one area, if the proton restarts its first position?

If an electron's position is very well defined, why does this cause its kinetic energy to rise?

Are there any developments on the Riemann Hypothesis lately?

>>17017235
Why is it well defined in the first place? Is there perhaps something keeping it there...

Anons I got a Dover print of Emily Riehl's undergrad book to supplement another text. Is it worth digging into?

>>17018509
Nope

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conditional probability
https://onecompiler.com/commonlisp
[code]
;; Use defparameter to define global variables in the REPL
(defparameter *boxes* '((1 1) (1 0) (0 0)))

(defun run-bertrand-trial ()
(let* ((box (nth (random 3) *boxes*))
(first-coin (nth (random 2) box)))
(list box first-coin)))

(defun run-simulation (num-trials)
(let ((gold-observations 0)
(gold-box-count 0))
(loop repeat num-trials do
(let* ((trial (run-bertrand-trial))
(box (first trial))
(coin (second trial)))
(when (= coin 1)
(incf gold-observations)
(when (equal box '(1 1))
(incf gold-box-count)))))

(format t "Total trials with gold observation: ~d~%" gold-observations)
(format t "Trials where box was Two-Gold: ~d~%" gold-box-count)
(format t "Empirical Probability: ~f~%" (float (/ gold-box-count gold-observations)))))

;; Execute the simulation
(run-simulation 10000)[/code]
(there are dummies on /pol/ who need to see this)

If light is a wave, why can it be breaked down to smallest possible parts called the photons? A wave in the ocean cannot be breaked down to its smallest part unless you're talking about just one wave.

>>17016994
How long you wait before sending through each particle doesn't matter. Once you have a large enough sample size the interference patter will still appear.

>>17021631
What do you think water is made from anon??

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>>17016986
Scientifically, why am I me and not someone else?

>>17021669
>you're on the trolley tracks
I've never seen this version of the trolley problem before. Would you sacrifice your life to save other people on the other track?

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>>17021644
The reason why there is a wave on water is because water molecules are interacting with each other. The way how light is a wave is not like photons were interacting each other producing waves.

I am not knowledgable and am a beginner in all of this. Here is my question: People say the double slit, superposition, and entanglement are not weird, just that they are presented as weird.

How true is this? Are they just overhyped and not really 'breaking everday human logic'?

Does a knot have spooky action at a distance?
If I change the properties of the knot at one end, the nature of my string at the other end can be either knotted or unknotted.

Could particles be complex knots in some spacetimey fabric?

>>17022206
they are connected by the same rope, so it's neither spooky nor at a spooky distance.

>>17016986
>annas-archive.org
the OP needs to be updated.

>>17022250
https://4chan-science.fandom.com/wiki/Obtaining_textbooks has a good list for the OP, specifically https://open-slum.org/ which tracks library mirrors.

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>>17016986

>>17022203
They probably mean that the math that describes all those things (and QM in general) is not particularly complicated. It's mostly just basic linear algebra. However the physical effects are so outside of everyone's every day experiences is what leads to all the problems in their understanding.

>>17021631
>If light is a wave
Light is associated to a type of object in the universe we live in. A wave is a mathematical object. Saying "light is a wave" is the short way meant to imply that the behavior of light can be predicted by modeling said behavior with mathematical waves. Saying "light is a particle" is a short way meant to imply that the behavior of light can also be predicted by modeling said behavior from a mathematical "point particle". Light simply is what it is - you don't need a description of a dog with genetics or biology to have a dog exists. We're using math with waves and points to describe light; light doesn't "care" that it's surprising to humans that it can be described using both.

>why can it [be both wave and particle]
No one knows (no consensus in the community). Maybe pilot wave theory is right. Maybe wave funciton collapse is a real thing. Any attempt at explanation is just a theory

Smart people seem to like linguistics. Anyone know if there is a connection between the words
>wood (like wud)
>water (like watr or wudr)
I noticed how I was pronouncing it and realized the two sounded similar. Google didn't bring anything up.

>>17022849
No, just a coincidence I'm afraid. The etymology of the two words is very different. In fact the word for "water" in all languages may be the only word that can be traced back to a single common root - apa / aqua.

>>17016986
How do I explain scrotumniggas cat to a class of 5th graders? Can't find anything on the Internet

>>17016986
I'm trying to turn sodium bicarbonate into sodium carbonate aka washing soda. I've seen differing instructions on the internet. Basically you're supposed to heat it but some say different temperatures and different cooking times.
Does anyone know the correct temperature and cooking time? Also I heard that aluminum reacts with washing soda which would neutralize its effectiveness. Should I avoid using my aluminum pan to cook it?

>>17022924
The dictionary of Indo-European roots on my shelf is one of my favorite possessions.

>>17022266
i don't get it

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Will ice cubes actually sink in warm enough water? Because according to this chart ice seems to have greater density than water at something like 80 degrees celcius

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>>17026947it
I'm not sure where that chart got it's data from, but the ice density looks wrong. In fact it shouldn't be a smooth graph, there's a discontinuity at the freezing point. The correct numbers should be much lower. All this means is that ice would still be less dense than hot/boiling water.

>>17026962
That's just one of the charts that popped in google image search. But they all looked similar and smooth curves.

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A neutrino detection device works by having a tank full of water and surrounding it with very sensitive cameras. When a neutrino messes with an electron of a water molecule, it creates Cherenkov light which is detected.

Does this mean that if you went to the bottom of Mariana trench with a submarine where sunlight could not reach at all, and you had a very sensitive camera, you would see tiny flashes of light as neutrinos interact with the water molecules?

>>17027329
Think about it. The phase change from water to ice means the graph can't be smooth.

>>17027746
That's what I thought. And that's why I thought the graph was strange

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I don't know if this question can be answered but how many streets loop vs how many end? Or, what percentage of streets loop vs end?

To expalain. Say a simple version: street A terminates at street B, street B terminates at street C, street C terminates at street D and street D terminates at street A. That street loops.

vs
Street A terminates at street B but street B terminates and forces the driver to turn around at its end. Even though A terminates at B because B terminates with no outlet, street A can be said to end.

This of course would be directional as many streets terminate at places where a left or right turn is possible. I would claim that most streets loop, but I don't know and I don't know how I would go about proving that. There's a lot of Cul-de-sacs and dead ends out there.

I am an undergraduate economics student, recommend me must-read scientific literature regarding economics /sci/.

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>>17028438

>>17028436
They invented graph theory for this, there are also sparse matrices you can populate with this info with a bunch of time, a machine learning algorithm, and google maps (they will cut off your API access before you actually get enough data to do the answer though -- you should probably stick to scanned images of old map atlases)

>>17028667
I didn't laugh

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how do i know if a textbook will be good or bad?
for example if i want to learn to learn about mathematical logic how do i find a good textbook for it? without wasting time trying loads of textbooks until you realise they suck

>>17028757
Most people don't laugh at things that aren't jokes. Good on your for having all your marbles together.

>>17025359
Not all ovens are the same. Honestly, if you're trying to determine yield percentage, you could try measuring the weight difference (iffy) or measure pH (also iffy if you don't have the tools). Try out a ceramic pan to avoid risk if you want.

>>17020775
hmm?

>>17022250
yes

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Pi to the power of square root of two. Is this an irrational number?

this is kind of outside of the scope of whats being asked for the thread but you guys ever see shit that you can't find any reasonable explanation for? weird personal experiences or even just spooky vids on the internet?
do those kinds of things just strike you as entirely fake despite how unsettling it may appear to be or whatever personal claims have been made about said videos? or are those sorts of things you just shrug and say maybe about?

>>17031543
Irrational, yes, but also transcendental

That's only true / proven for integer powers of [math]\pi[/math]. It's still an open question if numbers like [math]\pi^{\pi}, \pi^e, \pi^{\sqrt{n}}[/math] are irrational - though most believe them to be true.

>>17033985
My favorite one is the fact that nobody knows that pi^pi^pi^pi is not an integer.

If neutrons need to a stable nucleus with protonts to exist and can not exist by themselves and decay with a half life of 15 minutes, how do neutron stars exist?

When a neutron decays it creates a proton, electron and electron antineutrino, so when a supernova creates the core that becomes a neutron star and the compression forces the electrons and protons together where does the supply of electron antineutrinos come from to create the neutron? Asking for a friend.

>>17034382
It's all to do with energy levels. The reason a free neutron decays is because it's slightly more massive than a proton so decaying results in a lower energy state (a proton). Inside atoms, nucleons have discrete energy levels (just like electrons do in their orbital shells). If a bound proton already occupies a particular quantum state that means a neutron can't decay into the same state due to the Pauli Exclusion Principle. That's why neutrons inside atoms are stable. They aren't allow to decay due to the laws of QM.

It's a similar reason why neutrons are stable in neutron stars. The particles are compressed so much all the lowest energy levels are occupied, there's nothing left to fill resulting in the completely opposite particle reaction of p + e -> n being more energetically favourable.

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Did humans always find animals to be cute or was it parallel evolution as a result of animal husbandry? I imagine there is little evidence on account of writing of sufficient quality appearing too late.

>>17034382
[math] n \rightarrow p + e + \overline{\nu}_e [/math]
[math] n + \nu_e \rightarrow p + e [/math]
[math] p + e \rightarrow n + \nu_e [/math]

mathwise, a particle going forward in time == antiparticle going backwards in time
reorganize your particles, ensure 4-momentum conservation, and voila
(observe the lepton number conservation)

If gravity is not a force but only the distortion of space-time due to mass, then why does there need to be a Higgs particle or field?

>>17034817
Idk

Humans find human babies to be cute and the babies are evolved to be cute to promote the baby's survival. We're evolved to like cute things. Lots of animals like elephants and dolphins probably find other species to be cute too. Cute girls are also advantageous, cause eye candy makes boys happy.

>>17035280
Physicists want to force a concept called local gauge invariance into Lagrangians that they care about cause it leads to the right equations like Maxewell's Eq, and it also works for the strong force too. Using it forces one to tack on a massless gauge field to the Lagrangian. For electrodynamics (E&M)and chromodynamics (strong), this is fine and the photon and gluons are massless. But the Z and two W bosons for the weak interaction are not massless. One could ask, is there any way or case to incorporate a massive gauge field with local gauge invariance?

The Lagrangian T-U for a Higgs particle has symmetry to it (like an even function), and the Higgs potential U has continuous symmetry including about the ground states, so like if the two parameters are x and y where (x_min)^2 + (y_min)^2 = constant. You can "break" the equation symmetry by doing a variable change or transforming about any one of the infinite ground state solutions of the aforementioned equation. After expanding, you'll find the Higgs particle pops out (also something called a Goldstone boson but wtv)
When you try to enforce local gauge invariance before all of this - meaning you have to also add that massless gauge vector field like the others - performing the variable change to break the equation symmetry will not only create the Higgs, but the terms associated with the added gauge field now have a non-zero mass associated with it. The end result is a Lagrangian with local gauge invariance and a massive gauge field instead of massless. So if the Higgs particle exists, then there exists a way for massive gauge fields to have local gauge invariance, the weak in particular.

The Higgs also interacts with fermion fields - which start out as massless - via some Yukawa potential, and again by rewriting it/breaking the symmetry, you can give them mass.
Gravity doesn't endow mass to anything, it just describes what happens when you do. Interaction with the Higgs endows mass

Going back to finish my EE degree and want to use my old credits to save on money. What's the best way I can study and refresh myself on the material? I've basically forgotten almost all of calculus, physics, and electronics and have struggled a bit trying to re-learn it all.

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someone tell me how true pic is I dont understand why briefly looking at 10% coverage would be more dangerous than briefly looking at a normal sun. There is a eclipse tonight and I usually see the sun from my window at the correct time of the eclipse.

>>17035484
A solar eclipse means you are not looking at the sun, you're looking at the moon

>>17035484
>briefly looking at 10% coverage would be more dangerous than briefly looking at a normal sun
Dude, that image in no way implies that. It says to take the same precaution in either case, nothing more.

How do I stop being a retarded ADHD chud? I'm trying to learn calculus but my retard brain can't help getting stuck on trig.
And every time I've tried to learn programming I can't stick to it for more than a week.
I've tried every amphetamine and Ritalin type drug, all useless.
Straterra works a bit, but I still can't stay focused.
I've blocked every doomscroller on my pc and limited the browser on my phone to 30 mins and it still isn't fucking working.
How the fuck do I condition myself to be an actually useful human being instead of a worthless wastrel?

>>17035911
Study English or law or paramedic or something? Why are you forcing calculus? To get a career using it that you'll also feel anxiety in? Not being an ass, I'm just old. I wish, back then, I knew the advice I just gave.

>>17035913
The problem is I don't like law, don't really care about English (plus it's about as jobless as you can hope to be) and I don't like people very much, and hate high pressure, so medical fields are unappealing.
But I really like machines and electronics and all of those fields need math.
I've been a mechanic, and it's OK, but I'm sick of being constantly covered in grease, oil, and various other filth, while destroying my body and getting paid shit.

>>17035917
>English (plus it's about as jobless as you can hope to be)
I meant "teaching English," but I should've specified that. Sorry. They make a great living, and you can choose a small town school, or a virtual school, or a private school, or a religious school, or etc. Likewise grade-level. Small kids. Adolescents. Community college. University. I suggested this because you're a coherent writer.

The same applies to math. If you know algebra well, you can take an algebra Praxis tomorrow and be qualified. Or geometry. Or elementary math.

"Hating people" is a complex thing. I'm an introvert but I like teaching to students who are well-behaved and are at school to learn, not just to be babysat. You seem similar. Again, your writing is well-thought-out. All teaching consists of is step by step explaining large concepts. Like why you need to learn calculus. You'd be surprised how many people can't. They're like "I just need to. Jobs and stuff."

>>17035919
My main problem with people is I don't like them depending on me.
I'm very absent minded, so I often make stupid mistakes, and then I struggle to get past even the smallest fuck-up.

I do quite like talking to people as well as explaining or teaching things. But I don't try much anymore because most people refuse to accept or understand anything they even slightly disagree with, either completely ignoring it, or worse, intentionally finding an extreme edge case that contradicts the norm.
I think if I had to teach people who were even close the modern, online, level of intellectual laziness and reticence I would hate my life.

Really all I want is a job where I can work 40 hours a week and have enough to buy a small house in an affordable area, some land to grow some tomatoes and chickens, and have some energy at the end of the day to actually do that.
Of course I have dreams of becoming some great big guy, but I would like it to not be a hail Mary with all my eggs in an imaginary basket.

Out of curiosity, are you a teacher?
I assume you are based on what you've been saying.
If so, what do you teach? And how is it working out for you as a career?

>>17016986
I thought the measurement problem in quantum mechanics means that any measure of a particle collapses Schrodinger's wave equation. Is this binary like on/off or can a wave function be partially resolved to limit its location more but not fully? And I thought measurement/observation meant any interaction with the particle at all. But I've been watching Sean Carroll and he says measurement is not fully defined in our current understanding or something. Can someone explain measurement/observation and whether it's a discrete binary thing or what exactly?

Standing still on the Earth's surface it is claimed that I am accelerating at 9.834 m/s2. yet as time continues I am still standing still and my velocity is still 0, so how can I be accelerating?

>>17036360
>I am accelerating
no you're not (in this context). Nobody says that

>>17036273
he is correct. There is no recognized well defined definition of a measurement or a collapse. If a particle collides with another, is there a collapse? Is it dependent on the number of particles? Is it a statistical thing, like how hot moves to cold because entropy is far to likely to increase? No good answers are given.

>>17036360
You are being pulled down by a force which would accelerate you at that rate if not countered by the normal force of the ground pushing you back up.

Alternatively, in the non-rotational reference frame, you have a velocity vector with direction parallel to the Earth's surface and magnitude equal to the sidereal velocity which is having its direction changed by that acceleration so that you move in a circle with the Earth instead of in a straight tangent line departing from it.

>>17036273
You can treat a measurement as if it causes the wavefunction to collapse because everyone agrees that the math of doing so works. No one can agree what it means and if that is what is actually happening. There is no such thing as a partial measurement, it's all or nothing.

what would happen to the world if we magically had infinite free energy? let's say perpetual motion is discovered, a perpetual motion machine is constructed, and it generates unlimited free energy.
what happens then? what happens to the sciences after that, how are the sciences affected? how are jobs affected? how is society affected?

I imagine electric companies would still charge people out the ass for it just because capitalism is the autoerotic asphyxiation of economic frameworks

>>17016994
https://youtu.be/lZ3bPUKo5zc?t=41m

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If the tectonic plates are moving at a certain level of pressure against each other, because of expected flows of magma, in such a way that we can predict how the continents are going to move for millions of years in the future, wouldn't it be possible to eventually correct for that movement and build ratchets or some form of expected notches for the plates to click along, so as to make the plates move like gears in a clock and nearly nullify massive unpredictable earthquakes in the future? You know, by spreading out the movement such that it's just a low buzz of movement people can barely feel, or even lower.

Obviously, we don't have the technology right now, but is there a pathway to that that's contemplatable? Could we turn our land plates into ratcheting plates that minimized quakes at safe regular releases of pressure?

>>17037018
Even the deepest human made holes don't reach past the earth's crust afaik. Their movement is prob equivalent to a large number of nuclear bombs, if I were to guess (iiwtg).

Humans are very small, and the mass of continents are very large. This is like asking if humans can just make large water fans in the ocean so when we predict some tsunami is gonna happen we can turn on the underwater fans to push the water away; we aren't talking about a swimming pool here, it's the damn coast of the ocean. We're small, and they're big. If a meteor was headed towards earth, the goal would be to nudge it slightly so it misses, not to drastically change it's momentum.

>>17037018
The 'plates' are blobs are different types of rocks and the stress regimes are always changing in geologic time, so the plate motions relative to each other change direction and velocity and are not predictable in geologic time and move too slowly for anything useful in human time. Look at the Hawaiin islands are now, and follow the line of islands up to the northwest and see how the line of island and subsea mountains bends due to the change in place motion over geologic time. No one knows how or why that changed. Also the current thesis is the San Andreas Fault is locked north of the Salton Sea up past Fort Tejon and a new plate boundary is forming east of it that will likely extent through the Walker Lane and eastern california shear zone. The plates are jumbles of different rocks and different depths and the plate boundaries change due to changes in rock strength and stress regimes. It may seem solid and predictable but it would be like trying to make gears out of poorly developed pie crust.

Why /sci/ is full of boring threads?

>>17037515
All the smart people left /sci/ and 4chan years ago.

>>17037609
There was never a time when smart people were in /sci/, newfag.

>>17037685
4chan and /sci/ had a higher average than most of the internet as the site self-selected for it. It was after word about it and the pastime of being a le ebin troll phoneposter got out to the normie retards that the quality took a nosedive and smart people stopped putting in effort.

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I plan on taking a neuro-psych exam to see if I have ADHD/anxiety vs being insomnic, thing is I've taken a bunch of bullshit IQ tests when I was younger and especially on the RPM, last one I did was the Riot IQ test August of last year and the evaluation is scheduled in November. Should I bring it up to them that I'm an autist obssesed with my IQ so they can (hopefully) give me a test that's more valid?

is math better done on a chalkboard rather than a whiteboard?

>>17037922
Writing things down physically tends to produce good effects in memory and comprehension. Whether this be pen, pencil, marker, chalk, or dry erase -- it's dependent on preference honestly.

I personally tend to cycle through all five options naturally, but I do like the tactile experience of chalk a lot. Make sure you erase with wet rags though as to avoid breathing in the dust if you employ chalkboards in enclosed spaces.

>>17036481
If we had infinite free energy, we would fuck everything up even faster

>>17038273
Would overheat Earth, because it's not easy to get rid of heat in space.

If electricity and magnetism are essentially the same thing, then the electron should be the magnetic monopole?

>>17038638
electricity and magnetism are the same *field*, that doesn't mean they have the same *charge*.

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Looking for the sauce of picrel.
Tried all of the typical reverse image search engines already, and the only thing that came up was a Russian blog post that didn't state a source.
The usage of a Likert scale suggests that it was at least a real study and not just something a random guy on Twitter mocked up, but who knows.
"QI (Média = 100)" might indicate that it was a Portuguese study? But then the rest of the labels are in English.

is Sleep On Physics a good yootoob channel for lengthy detailed explanations about physics?

In Naive Set Theory by Halmos, he states:
"The explicit definition of an ordered pair ((a, b) = { {a}, {a, b} }) is frequently relegated to pathological set theory." What does he mean by this? Or rather, what sorts of logical fallacies can arise from Kuratowski's notion of an ordered pair?
I fail to see the potential issue at hand here and would like to be made aware of it. I can read whatever you send me.

>>17041553
The term "pathological" has rather eyebrow-raising properties for most English speakers, but it is important to study multiple pathological definitions as they are designed to keep one's mind aware of the peripheries in the axioms we take for granted. In set theory it's best to study as many approaches to it's plethora of definitions as possible, as it can help you understand whether YOUR work is weak or strong, unrefined or refined.

>Halmos

He's better saved for when you want to review an undergrad book. If you want to start in a spot that doesn't leave anything obscured, I'd pick up a one-semester undergrad book in set theory and then go from there; set theory books are all the same. Just get some random dover print, or if you feel like it a Springer print (physical book, or pirated pdf).

If you feel like challenging yourself afterwards, I'd buy Axiomatic Set Theory (Dover print) by Suppes. It's an old book and very difficult as such AST books were at the time, but it's quite a useful window into things as-they-were-developing.

>>17041553
>"The explicit definition of an ordered pair ((a, b) = { {a}, {a, b} }) is frequently relegated to pathological set theory."
It's a type_theory tier lie. This definition is perfectly fine. 100% accuracy in language is what make math accessible, not bullshit handwaving.

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Would the old ice sheets actually have had miles of sheer cliffs like this on land, or would there have been an unceremonious gradient?

>>17042482
Both are possible depending on the underlying land topology and weather.

>>17042901
Do feel free to describe which conditions lead to which outcomes.

>>17042482
>miles of sheer cliffs
No, the snow fall that accumulates to create the ice does not magically stop at some magic latitude. Its thousands and tens of thousands of years of snowfall piling up and as you know the weather patterns change form one storm to the next, some temps warmer or cooler some moisture higher or lower and these changes cause avalanches and mass flows. Glaciers are not homogeneous and can develop deep and wide crakcks but I I do not know of any situations where there mile high sheer cliffs nor how they would form

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>>17016986
Could someone clue me in real quick or does this question deserve its own thread: to my understanding, QFT is usually only done perturbatively, and from what I can tell, can only deal with asymptotically free particles. Any bound system as simple as the Hydrogen atom ought to effectively break this approach because an electron trapped forever obviously violates the asymptotic assumption.

Has there ever been any progress made for that? My background is QM of bound systems and scattering problems and I find the scattering of elementary particles unfathomably boring.

>>17043303
You're correct. A non-perturbative QFT does not exist, so it does not work for bound systems. As for the scattering of elementary particles, that isn't really much of a choice since it is the best method we have to test QFT.

>>17043339
That's a real shame, I never heard this discussed at all in high energy physics discourse, what little I saw of the literature at least. Since all I do is far below their usual energy scale I don't wanna sound like a backseat theorist but to me that seems unfathomably alarming, especially since I have seen people claim to add alleged QFT perturbative corrections to unfathomably high res atomic spectra.
A huge problem when trying to look into these things for me, having talked to high energy physicists in private, is that a lot of them seem to think chemistry/molecular physics is "solved" and QFT has no reason to bother with things as trivial as the majority of directly observable matter in the known universe. It's sad because what interests me is the nature of tangible matter first and foremost.

>>17043345
Depends what they mean by "solved". We have the equations, we just don't have the computing power. Hell, we still struggle to calculate the precise energy levels of the helium atom. So for all practical purposes chemistry and molecular physics are still very open fields.

>>17043303
Postdoc here (scattering amplitudes).

There are QFTs in which you can do more because of special symmetries or dimensions (for example, maximally supersymmetric Yang-Mills theory in 4d, which admits integrability).

Anyways, for many QFTs, the way we address the problem of "compute something" is by perturbing around a free theory (which we know) and adding a term proportional to a coupling constant g in the Lagrangian. Then observables are asymptotic series (think: Taylor series but doesn't have to converge) in this g, and we compute the terms in these series.

What people mean by "non-perturbative" is that there are functions that *don't* have a Taylor series, and in a sense are invisible to this approach. The simplest example is exp(-1/g^2), which has a Taylor series of 0+0+0+... around g=0. There are things you can compute in QFT that functionally behave like exp(-1/g) (renormalons, instantons, among others) and are thus called non-perturbative.

There is also the hope/believe that if you know ALL the terms of a pertubative series (that is expected to diverge) it can be still summed via Bore resummation, and then you would see such non-perturbative terms.

Anyways, at a philosophical level, there is always numerics! Lattice QCD does allow you to compute observables even if you can't do it by hand.

Is the quantum foam of space the aether through which light propagates?

>>17043762
No. There is zero current evidence for any kind of aether.

>>17043762
Yes. There is loads of accumulated evidence for some kind of aether.

>>17043762
Underdetermination of data tells us that we can't conclusively demonstrate if the evidence we have is for or against aether theories.

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What is this data distribution in this graph called ?

>>17043819
>>17043967
>>17043975
so Schrödinger's aether is there or not for light to propagate through.
But, it seems light at least propagates through the fabric of space-time then, which is something rather than nothing, at least consisting of foam and all the fields.

The quantum foam is created by the fields interacting with themselves?

>>17044238
Not exactly. Quantum fields have two relevant properties. The first is that they have a minimum non-zero energy (their zero-point energy) and because they are quantum in nature the uncertainty principle applies to them. An uncertainty in energy can be regarded as the field vibrating (the foam) and a vibration in a quantum field is what we call a virtual particle. So those virtual particles could then interact with those in other fields, but those are higher-order (more unlikely) terms in the calculations.

>>17044114
A discrete distribution

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Anyone here written a wave packet propagation program before? I have ages ago and used a bog standard implicit runge kutta integrator under the hood. I would like to redo it in my free time eventually and wonder whether I should look into what integrators are actually popular these days. I don't feel confident on that front.

>>17044635
Why change the method? It's straight forward to implement and still in use over a century after its creation because it works.

>>17044636
You are right, and the integrator usually only shits itself when something else is seriously wrong (potential, bug in the kinetic energy operator if you use curvelinear coordinates..). I suppose my internal line of reasoning was "I blindly use this method I do not truly understand, maybe I should put in more effort to fix the blind spot".