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Crypto HNQ

05:53

Q: If OWF were to exist, do we know for sure that one of the candidate OWF would indeed be a OWF?

We have several candidates for OWF, like multiplication/factoring and discrete exponencial/logarithm. What I am asking is: Does the existence of one way functions imply that our candidate functions are indeed one way functions? Is there a candidate one way function whose one wayness is directly t...

2 hours later…

Maeher

07:55

Another week, another bomb found...

Maeher

08:50

crypto.stackexchange.com/posts/81485/revisions

I'm not sure this edit makes sense.

Yes, the question is much clearer now to someone who knows what a fixed point is, but e.g., the original poster would probably not have realized that the edited question asks the same thing.

Thomas

haven't been here in forever

2 hours later…

kelalaka

10:25

What happens to OP's points when two questions are merged? What happens in the future upvotes?

@Maeher I was between reject and accept. The OP should have been realized that after got an answer and duped. I accepted since it should be clear to all.

fgrieu

@bdegnan Except cryptanalysis, I can't think of a practical application of ASICs/FPGAs with true 4096-bit words and a multiplier with output (or inputs) that wide. Isn't the 4096-bit really holding many smaller words, e.g. 128 sub-words of 32 bits? That can have a lot of applications in high-speed signal processing.

b degnan

11:25

@fgrieu I'm sure that was the case. Sadly, I spent my whole career just saying "yes" to money. Working with ICs is super expensive due to both the fabrication cost and the time it takes to get back from fab. If you get your Ph.D. in RF related things, it takes 3 years. If you do it in semiconductors, you are lucky to do it in 7. (It took me 7 due to fab turn around).

to that end, I really have no idea what most of the stuff that I was involved in was used for. :/

1 hour later…

SEJPM

12:29

@kelalaka first note that merging is stronger than marking as duplicate as with a merger (mod-only) you also transfer all answers and comments to the original post

The closed post author I think gets to keep all the rep from upvotes and the like

but won't profit from future upvotes on the original post

kelalaka

@SEJPM yes it is stronger. Giving future upvotes a hard issue to solve I guess. So better left there.

So what do you think about merging

Q: Does there exist a hash function which has a fixed point?

Does there exist a hash function $h$ and an input $x$ such that $h(x) = x$? I believe this is a special case of collision-resistance. I imagine such a case is guaranteed not to be possible (otherwise such a hash function wouldn't always be guaranteed to be useful), but how is such a case proven t...

hash collision-resistance

With the duplicate?

SEJPM

ohh, I just realized they confirmed the duplicate vote themselves

so the fixed point is the right interpretation here

yeah, then merging is sensible

kelalaka

Need a flag :)

So there the community = themself?

SEJPM

no, no flag needed

yes, if the closing user is community for a duplicate vote, the OP confirmed that it's a duplicate

merged.

(it needed a bit of comment and answer cleanup prior)

kelalaka

12:48

I saw, thanks.

7 hours later…

kelalaka

20:07

We have 19 John Doe's and around 64 Anon*s

SEJPM

@fgrieu congratulations!

election chat room for your convenience:

2020 Cryptography Moderator Election …

Open Discussion for crypto.stackexchange.com/election/4

kelalaka

Ah, finished. congratulations @fgrieu

SEJPM

Also thank you @kelalaka and @poncho for nominating!

Meta Crypto SE

20:20

Q: 2020 Moderator Election - Results

Cryptography's fourth moderator election has come to a close, the votes have been tallied and the new moderator is: They'll be joining the existing crew shortly—please thank them for volunteering, and share your assistance and advice with them as they learn the ropes! For details on how the voti...