The h Bar - 2023-06-20 (page 4 of 4)

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6:01 PM

Or maybe that wouldnt have been possible because of the legal contracts

The unit-731 data apparently helped in advancing medical science

But how much true is this

Many scientists would prefer not to use data gathered in such abhorrent circumstances.

I am conflicted about this. The damage that was done could not be reversed. But the data did help reduce future human suffering (assuming it was helpful)

So, at that moment of time, is it just the best decision to accept that data

They probably could have broken their promise of sparing the scientists though

is this chat just where you post your thoughts?

like, not the result of some thinking, but just whatever pops into your mind as a first reaction to something?

I think i do sometimes reply impulsively. I will not do it again

It's complicated. The data can help humanity. And it can be seen that ignoring that data makes the deaths totally pointless. But I suspect that your average prisoner being subjected to such treatment doesn't have particularly positive feelings towards humanity in general, at that stage...

6:10 PM

@PM2Ring i also think it sets a bad prededent that you can get away with those war crimes

@RyderRude Agreed. IMHO, letting such people off is a war crime in its own right.

It's a very complex situation overall. The only solution i see is that they should've gotten the data and then not spare them anyway :P

@PM2Ring Thanks, I looked there but only now I see it "In 2000, the Department of Commerce implemented rules that greatly simplified the export of commercial and open source software containing cryptography, including allowing the key length restrictions to be removed" , only in 2000!

PGP was originally published in New Zealand, so that it wasn't being exported from the USA, and even that was problematic.

And PGP today is the model of how not to build secure encryption :)

Not that it can't work, it just has so many issues

6:19 PM

US also displaced some island natives to test nuclear weapons

There is a new encryptiom technique that is a lattice based model

I thought it was too fancy... like those hacking scenes from Hollywood lol

But it apparently can beat quantum computing

It is in this video

More precisely: no quantum algorithm was found that can break it, as opposed to RSA , DH family algos

Oh

But a classical attack can be found tomorrow that breaks either RSA/DH variants or the newer Kyber algorithm I think you're referring to

Is there no way to prove that there exists no such attacking algorithm

Like we proved the halting problem cannot be solved

From The Nazi Hypothermia Experiments: Forbidden Data?:

> Even if the data were of the highest quality, its provenance should surely put it out of bounds to the ethical scientist. In making use of these results we are offering a veneer of respectability – however thin – to doctors who have violated in the most extreme way imaginable the essence of their calling. And medicine itself is demeaned.

6:31 PM

With regards to RSA/DH it's because no one knows if factoring is a hard problem or not (see: RSA problem), it just seems to be from all practical experience. Same for the discrete logarithm problem, I think those two were also shown to be equivalent. Nice page about it here

And "hard problem" is a technical term here, I guess. Like a non-polynomial time problem

@RyderRude No that's just the point, no one knows if it's "in P" or not... I wish I knew enough computer science to tell you exactly what it means. For a hobbyist like me P just means computationally easy

But yes all these things can be defined technically, somehow in terms of the complexity of the algorithm required to solve the problem. Even if it's only asymptotic complexity

It is so crazy that a shortcut technique to prime factorize may exist

They also don't really know if $P = NP$ or not but that's a different matter

I know that problem :P it is expected that they are not equal, i think

6:34 PM

It would be sensational if they can be shown to be equal

Also if they can be shown to be not equal -- but less so :)

Even if they are equal, the polynomial time may just have a very large degree, which would crush those dreams of computation utopia

Yes, it makes me think that this thing will never be proven either way

And even a quantum attack on RSA or discrete log systems doesn't totally break the crypto. It just means you need to use longer keys. And there are (currently) no feasible quantum attacks on any crypto algorithms apart from RSA-like / discrete log systems.

And of course, there's also no guarantee that we'll ever be able to make a functional quantum computer with enough qubits & a low enough error rate to make an attack feasible on modern key lengths.

@Amit there is a very interesting result that a non-linear modification to Schrodinger equation leads to quantum computing algorithms that make p=np

@PM2Ring That's right, the problem is that these algorithms are so very slow even with the present key lengths, and if a scalable QC technology comes into being, it would be a very bad "cat and mouse" game to play :) I mean the mouse (key length) will not scale as well as the cat :)

@RyderRude Non linear SE, that is, not the SE that really works in nature? :)

6:41 PM

@Amit it is not known what happens beyond our error margins. Some people hypothesize non linear Schrodinger eqn too even tho it's ugly

I personally dont support it

I'll support it if it works ^_^

This p=np thing is also used as an evidence agianst non linear Schrodinger eqn

Because p=np is too crazy to be true, according to that argument

It's nice to find equivalences like that, it sounds like a computer science + physics collab

@Amit True. Scalable QC would force us to abandon RSA & discrete log algorithms. OTOH, there are other ways to do crypto, and scalable QC would be pretty awesome for all sorts of other stuff. ;)

@PM2Ring Oh yeah, I would definitely give up on RSA and DH, lovely as they are, in exchange for scalable QC :) It would be crazy and awesome in all sorts of ways

I just hope it isn't actually already here and just kept classified for the next 30 years while everyone is letting the quantum bubble grow <_<

6:47 PM

What are the promises of scalable QC

You'll be able to do some crazy physics simulations apparently. Stuff that you can't do today exactly because of the exponential number of degrees of freedom a quantum state has

I guess technology in that future would look alien compared to today

And improving simulations capabilities always implies a lot of benefit for a lot of fields down the line

Is it just simulations? What about other things like everyday technology

The simulation thing has implication for technology of course

If you can use it for example to discover new kinds of molecular structures

Optimized to do certain things

It's all hand wavy I know :)

6:51 PM

At this rate, we would invent teleportation in 300 years

Magic is just technology of the future

Don't put me in first, Scotty

Please quote it right... "Any sufficiently advanced technology is indistinguishable from magic" :)

Yes. Thanks :)

The classic teleportation comic. existentialcomics.com/comic/1

7:44 PM

Oh dear...

-21

Q: Starting the Prompt Design Site: A New Home in our Stack Exchange Neighborhood

Today, I have some news to share. It's about one of our newest projects coming to the network - the Prompt Design Stack Exchange site: a site for Q&A on writing or engineering effective prompts while utilizing different generative AI (GenAI) tools. What is prompt design? Prompt design or prompt e...

discussion featured announcements

I see SE continues to try to set a new record for "how many trash fires can we set off while ignoring internal feedback that this is a really bad idea in every single instance"

They could have at least waited until the strike was over. But maybe they really are trying to upset people...

8:00 PM

lol, the minus votes on that increase as I watch

I wonder if that last bullet point in the post was really the goal of the entire post:

> Lastly, suggesting a prompt design site on Area 51 is not necessary. Other site proposals are totally still welcome there, of course. We’ve got this one, so do us a solid and don’t suggest any site proposals around prompt design or suggest to others that they should.

I'm pretty sure this is just another "CEO said we have to do AI so get on it" thing that no one is actually interested in discussing

they ignored all feedback they got on the moderator-internal preview of this and posted it anyway

Yes, the entire text gives the feeling of "someone is making me write this at gunpoint" a little bit, lol

I can't completely fault people who just wanna keep their job, and maybe hope a better management may come along, or a better job offer

I mean SE used to be good at this

but they fired all the people who were responsible for them being good at it, I guess

@PM2Ring reminds me of camus' novels

8:15 PM

@ACuriousMind It's easier to manage less opinionated employees of course. Anyone that compares the kind of people who work at start up companies vs. established companies sees this

oh, I understand the logic of capital

@SillyGoose Well, Camus was one of the founders of existentialism.

doesn't mean I have to like it

Yeah, of course. I wouldn't lay out something so obvious if it wasn't a public chat room actually :)

indeed but even the particulars :P I think a happy death and the fall have some cycle of revelation, debauchery, acceptance

but the acceptance at the end does seem very much in the spiritt of camus

whenever a scene to do with farming appears i think of tolstoy's pierre :P working the field in peace

oops not pierre, it is levin

8:26 PM

I haven't read any Tolstoy, you're safe :P

there is a character pierre in war and peace and a character levin in anna karenina and in my opinion they are very similar :P I think they both act as character stand-ins for Tolstoy himself

pierre goes from doing nothing to wanting to assassinate Napoleon to joining the free masons :P

that's about what i remember these days

pretty relatable

9:08 PM

Just realized that the Riemann tensor of the maximally symmetric spacetime is the kulkarni product of the metric

whaaat

Makes sense I guess, you only get the part of the curvature that influences changes in volumes

9:27 PM

Proposed metric (pun intended) for the level of your GR knowledge: percentage of statements @Slereah makes that you can understand 🤣

But please keep them coming, I find them motivating

9:41 PM

@SillyGoose Levin was cool when I read it, but now I think I'd have more sympathy with Anna and question the mentality behind some of it I'm not sure

@Slereah According to wikipedia this is completely obvious :p

Kulkarni–Nomizu product

In the mathematical field of differential geometry, the Kulkarni–Nomizu product (named for Ravindra Shripad Kulkarni and Katsumi Nomizu) is defined for two (0, 2)-tensors and gives as a result a (0, 4)-tensor. == Definition == If h and k are symmetric (0, 2)-tensors, then the product is defined via: ( h ∧...

I mean I guess, but I don't think about the Kulkarni product that much!

To your detriment it seems

Yeah I need to get into it

Like apparently you can interpret it as a map between 2-forms

Wondering if that relates to like the 2-form defined by the infinitesimal holonomy

Also I am suspecting it relates to that whole SL(n) structure thing in GR

Is it like mapping the 2-form of the holonomy to the 2-form defined by the original and transported vector

$(h \wedge k)_{ijlm} = 4 h_{[i|[l} k_{m]|j]}$

And if so what makes it different from the rest of the Riemann tensor

I guess since it's in the "volume only" part of the Riemann tensor that only affects the norm or something???

Mb I should just check how the parallel transport affects the volume form

9:50 PM

It's just that simple map in form language, and it appears in the constant curvature tensor naturally, I don't see the magic

We shall see

10:09 PM

Actually two of the tensors in the decomposition are kulkarni products

But the Weyl is not I guess, is it relevant that it cannot be decomposed like that

@Slereah I think it's because it's the "Ricci-flat" part of the curvature?

Trying to get some intuition on it I guess

I think "producing the Ricci tensor" is in some sense the inverse operation to the KN product

and the Weyl tensor lies in the kernel of the "Ricci map", so it can't come from a KN product

I guess the $g \owedge g$ part implies that there's some relation between the angles defined in between the angles of the holonomy loop and the transport of the vectors

In a particularly pleasing way

10:24 PM

'\mathbin{\rlap{\,\wedge}\bigcirc}'

FFU :)

oh, do only old programmers know what it means actually? nvm, For Future Use :P

It is something like for a loop made by the sides $X$ and $Y$ to transport a vector $Z$ to $Z'$, you're gonna get something like... $$R(Z', X, Y, Z) = g(Z', Y) g(X, Z) - g(Z', Z) g(X, Y)$$

And I guess this is invariant under shear transformation?

There's a formulation of it using determinant which maybe makes that angle more clear

Actually one thing I should look into is how parallel transport works for the spherical and hyperbolic case, since that's essentially what happens here

Solstice is gonna happen in a few hours

More astrological probably than astrophysical, but still nice

10:45 PM

Hm

Mention that the Riemann tensor can be considered like a 2-form that's $\mathrm{so}$-valued

Does that mean that it doesn't have the same skew properties if it's not an SO connection

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