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New sphere-packing record stems from an unexpected source

quantamagazine.org

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Re: New sphere-packing record stems from an unexpected source

#121

Post by m463 »

pseudocomposer wrote: post #50
dkarl wrote: post #12

Earlier quoted context omitted.

I've found it's best to explain my job using unintelligible jargon. There are three choices, really: You can give a quick explanation in terms they understand, which makes your job sound easy and makes them wonder how anybody gets paid to do it. You can explain what you do and why it's important in terms they understand, but it'll take so long they'll get bored and wish they hadn't asked. Or you can give a quick expl…

When I meet people who immediately use hyper-specific jargon with strangers, I either distrust them, or assume they’re not emotionally intelligent (because it’s a choice demonstrates little respect for the person they’re addressing). It also projects that they may be compensating for some emotional insecurity on their own end, trying to assert intellectual “superiority” in some way. The first option (explaining thing…

I'm reminded of this dilbert cartoon:

https://web.archive.org/web/20230228154639im_/https://assets...

Re: New sphere-packing record stems from an unexpected source

#122

Post by jacobolus »

shkkmo wrote: post #85
jacobolus wrote: post #20

Earlier quoted context omitted.

Besides 2 and 3 dimensions, it's also the case in 8 and 24 dimensions (The E₈ lattice and Leech lattice, respectively). These were proven in 2017 by Maryna Viazovska, with some collaborators for the second paper. https://doi.org/10.4007/annals.2017.185.3.7 https://doi.org/10.4007/annals.2017.185.3.8 See also https://www.ams.org/journals/notices/201702/rnoti-p102.pdf For other dimensions, this is an open question; it…

> For some dimensions the densest known irregular packing is denser than the densest known regular packing. I thought that was one of the important results from the paper, the most efficient packing for all dimensions is symmetrical again and this increase was significant enough it seems unlikely that existing non-symmetrical methods will be able to beat it.

Perhaps so. If you hunt you might be able to find a new summary table somewhere (I didn't find one in a very brief skim around). My impression was this new work was more about high-dimensional cases than necessary a dramatic improvement for every low-dimensional example.

Re: New sphere-packing record stems from an unexpected source

#123

Post by zmgsabst »

Dylan16807 wrote: post #117
zmgsabst wrote: post #114

Earlier quoted context omitted.

That’s not my point, nor close to what I said. My point is that their models are fitted tensors/probability distributions, often retuned to fit new data (eg, the epicyclic nature of collider correction terms) — the same as fitting a DNN would be. Their inability to describe what is happening is precisely the same as in the DNN case.

If you have a very small neural network, you can fully understand and explain how it works. As you increase the detail of a description, it reaches a point where nothing is missing.

As I pointed out, eg, the high number of correction terms when trying to tune the model to actual particle accelerator data is evidence that our model is missing something. (And some things are plain missing: neutrino behavior, dark matter, dark energy, etc.)

In the same way that a high number of epicycles was evidence our theory of geocentrism was wrong — even though adding epicycles did compute increasingly accurate results.

Re: New sphere-packing record stems from an unexpected source

#124

Post by zmgsabst »

tbrownaw wrote: post #119
zmgsabst wrote: post #114

Earlier quoted context omitted.

That’s not my point, nor close to what I said. My point is that their models are fitted tensors/probability distributions, often retuned to fit new data (eg, the epicyclic nature of collider correction terms) — the same as fitting a DNN would be. Their inability to describe what is happening is precisely the same as in the DNN case.

... So it's about not being able to observe short-lived particles directly, and having to work backwards from longer lived interaction or decay products? Or about how those intermediate particles they have to calculate through also have empirically-determined properties?

Most of that is measured corrections, not a theoretical model.

Entanglement is just a statistical effect in our measurements — we can’t say what is happening or why that occurs. We can calculate that effect because we’ve fitted models, but that’s it.

Similarly, to predict proton collisions, you need to add a bunch of corrective epicycles (“virtual quarks”) to get what we measure out of the basic theory. But adding such corrections is just curve fitting via adding terms in a basis to match measurement. Again, we can’t say what is happening or why that occurs.

We have great approximators that produce accurate and precise results — but we don’t have a model of what and why, hence we don’t understand QM.

Re: New sphere-packing record stems from an unexpected source

#125

Post by ahazred8ta »

jimbokun wrote: post #88
jvanderbot wrote: post #60

Earlier quoted context omitted.

I don't see what's hard about threading the needle, or maybe I'm completely lacking in EQ "I'm a mathematician, I study how shapes fit together, which surprisingly, is being used for new methods of secure communication by so and so university, but I just love the math"

Or “I’m a mathematician. I try really hard to find things I can prove that have no practical application. But frustratingly people keep finding important practical applications for my work.”

> No one has yet found any war-like purpose to be served by the theory of numbers or relativity or quantum mechanics, and it seems very unlikely that anybody will do so for many years. - G.H.Hardy, Jan 1940 > A few decades later, we stand waiting for nuclear bombs guided by GPS to be launched when the cryptographic auth certificate is verified. So it goes.

Re: New sphere-packing record stems from an unexpected source

#126

Post by Izikiel43 »

Workaccount2 wrote: post #51
clickety_clack wrote: post #7

I have trouble explaining to my parents how my job is a real thing. I can only imagine trying to explain ‘I study shapes, but only ones that don’t jut inwards’.

I have my own micro business where I make equipment for high energy physics machines. I have yet to figure out a way to tell people what my business is in a way that is even slightly accessible. Everything about it is so esoteric and multiple steps removed from regular life. It's not necessarily complex, it just contains a ton of details that the average person has no familiar contact with, and don't really have ever…

I make gear for machines that throw energy beams/lightning/lasers?

Re: New sphere-packing record stems from an unexpected source

#127

Post by Izikiel43 »

clickety_clack wrote: post #7

I have trouble explaining to my parents how my job is a real thing. I can only imagine trying to explain ‘I study shapes, but only ones that don’t jut inwards’.

I practiced with my wife. Now I can describe my job as a service for making services.

Re: New sphere-packing record stems from an unexpected source

#128

Post by ahazred8ta »

YeGoblynQueenne wrote: post #67
dkarl wrote: post #12

Earlier quoted context omitted.

I've found it's best to explain my job using unintelligible jargon. There are three choices, really: You can give a quick explanation in terms they understand, which makes your job sound easy and makes them wonder how anybody gets paid to do it. You can explain what you do and why it's important in terms they understand, but it'll take so long they'll get bored and wish they hadn't asked. Or you can give a quick expl…

I once told my dad that if the subject of my thesis was something I could easily explain then it wouldn't be interesting enough to do a PhD in. I said it half-jokingly and he laughed about it, but he stopped asking me what I'm studying after that so maybe he did take it more seriously.

Introduce him to the annual Dance Your PhD contest:

https://duckduckgo.com/?q=dance+your+phd&ia=videos&iax=video...

Re: New sphere-packing record stems from an unexpected source

#129

Post by tbrownaw »

zmgsabst wrote: post #124
tbrownaw wrote: post #119

Earlier quoted context omitted.

... So it's about not being able to observe short-lived particles directly, and having to work backwards from longer lived interaction or decay products? Or about how those intermediate particles they have to calculate through also have empirically-determined properties?

Most of that is measured corrections, not a theoretical model. Entanglement is just a statistical effect in our measurements — we can’t say what is happening or why that occurs. We can calculate that effect because we’ve fitted models, but that’s it. Similarly, to predict proton collisions, you need to add a bunch of corrective epicycles (“virtual quarks”) to get what we measure out of the basic theory. But adding su…

> Entanglement is just a statistical effect in our measurements — we can’t say what is happening or why that occurs. We can calculate that effect because we’ve fitted models, but that’s it.

Bell's theorem was a prediction from math before people found ways to measure and confirm it. A model based on fitting to observations would have happened in the other order.

Re: New sphere-packing record stems from an unexpected source

#130

Post by nurettin »

pseudocomposer wrote: post #50
dkarl wrote: post #12

Earlier quoted context omitted.

I've found it's best to explain my job using unintelligible jargon. There are three choices, really: You can give a quick explanation in terms they understand, which makes your job sound easy and makes them wonder how anybody gets paid to do it. You can explain what you do and why it's important in terms they understand, but it'll take so long they'll get bored and wish they hadn't asked. Or you can give a quick expl…

When I meet people who immediately use hyper-specific jargon with strangers, I either distrust them, or assume they’re not emotionally intelligent (because it’s a choice demonstrates little respect for the person they’re addressing). It also projects that they may be compensating for some emotional insecurity on their own end, trying to assert intellectual “superiority” in some way. The first option (explaining thing…

> When I meet people who immediately use hyper-specific jargon with strangers,

That is 90% of the professors I asked questions to. If they go full jargon and don't want to explain any of it, they don't want you near them ( or they want you to improve before even having a conversation ).

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