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slack3r

Re:Proof by Contrapositive Is Wrong on Wednesday July 23, 2025 @06:50AM (#44657721)
You have to first prove that p is not undecidable. This is not being done in many proof by contra-positive based proofs in mathematics. First prove that p is not undecidable is not a step in Analysis I by Terence Tao for instance.

Proof by Contrapositive Is Wrong

Proof by contrapositive is wrong. There is a true, false and undecidable case also.Let me explain how it works.p. =>. q. does not necessarily imply not q ==> not p. There are three cases here. If not q is true, then p can also be undecidable.

( Read More... | 3 comments | on HN )
Re:Country-Wise Living Standards for an Amazon SDE 2 on Saturday January 27, 2024 @02:24AM (#39153426)
They are living in some very tiny house. Housing is the highest expenditure present.

I calculated the rates for 111 square meters.

Re:Country-Wise Living Standards for an Amazon SDE 2 on Saturday January 27, 2024 @01:39AM (#39153220)
I calculated the living expenses and savings ratio for every country that has an Amazon SDE 2 role on levels.fyi.

For instance, for food I used the Big Mac Index, and got data from various sources on the Internet.

I did some spot checking of minimum wage employees, the trend seems to apply to them too, although I haven't checked in more detail.

Missing Metrics: - Cost Of Education - Healthcare - Ease Of Switching Jobs

All three of these metrics are complicated to measure due to the different preferences that people have.

Re:Ask HN: Leaving a Job at Big Tech Giants for Startup on Sunday February 24, 2019 @12:21PM (#19239444)
If you have to ask, you should probably stay at Big Tech Giant.
Re:Who Owns Buried Treasure? on Sunday February 24, 2019 @12:18PM (#19239430)
IMO : If it's on private property, whoever owns the property. If it's on public property then the government.
Re:Google Maps: Bird Mode on Sunday February 24, 2019 @12:12PM (#19239402)
Or the other paranoid conspiracy theory interpretation is that the CIA wanted to call it Bird mode to avoid freaking out people. See https://pando.com/2015/07/01/cia-foia-google-keyhole/
Re:Stream Ring Theory – A Turing-Complete Stream Algebra on Sunday February 24, 2019 @12:04PM (#19239359)
sed is already Turing-complete (https://catonmat.net/proof-that-sed-is-turing-complete).

I'm not sure how what you are proposing is any better than sed. I said math envy since you resorted to using algebraic ring theory when there was a much simpler solution. xD

Re:Ask HN: How Would You Explain HN to a Two-Year-Old? on Sunday February 24, 2019 @10:45AM (#19238978)
I would say it's a place where people who spend a lot of time on the internet try to gain status by posting comments which they expect to be upvoted.
Re:The Cost of Abstraction (2016) on Sunday February 24, 2019 @10:42AM (#19238963)
Abstraction is useful when the resulting code is logically simpler, much like say category theory makes certain results in algebraic topology seem obvious.

Perhaps, you simply mean a different thing when you say "abstraction".

Re:Stream Ring Theory – A Turing-Complete Stream Algebra on Sunday February 24, 2019 @10:39AM (#19238953)
Classic case of math envy. Ha ha ..
Re:Ledger's Advanced Side Channel Analysis Repository on Wednesday February 20, 2019 @03:01AM (#19206395)
> I'm super impressed by the creativity involved in these attacks.

You should check out [Acoustic cryptanalysis](source: http://www.nuclearphynance.com/Show%20Post.aspx?PostIDKey=15...)

Re:Flavors of SIMD on Wednesday February 20, 2019 @01:34AM (#19206063)
Don't be ridiculous, dude. No compiler is actually compiling to PCMPISTRI. It's meant to be used directly as assembly.

Of course I could be wrong. If you do know of any open-source compiler which compiles code to PCMPISTRI, let me know.

Superoptimization is not exactly exponential, it is NP-hard.

Of course, in the paranoid conspiracy I was referring to in my previous comment I predict the NSA/GCHQ is also using this directly via assembly. xD

Re:Flavors of SIMD on Tuesday February 19, 2019 @12:37PM (#19200898)
Lol, my comment was restricted to SIMD, which definitely does not take 10 minutes.

Secondly, no mainstream compiler actually compiles code to the PCMPISTRI instruction. Presumably it was meant to be used directly as assembly. I'm not sure why you are bringing in this obscure instruction into the discussion of superoptimizers.

I personally have a paranoid fantasy where NSA/GCHQ introduced this instruction to speed up password cracking. :D

Re:Flavors of SIMD on Tuesday February 19, 2019 @10:19AM (#19199494)
It may be black magic now, but people are working on making the black magic something lesser mortals don't have to worry about (eg: https://theory.stanford.edu/~aiken/publications/papers/asplo...)

Unfortunately, no one is actually paying attention to all this research being done in ivory tower academics. Sad!

Re:Deep learning may need a new programming language on Tuesday February 19, 2019 @10:11AM (#19199427)
Yes. Deep Learning definitely needs a new programming language. Uber's Pyro is worth checking out. (https://eng.uber.com/pyro/)
Don't be ridiculous. It's better for technical books to be freely available for everyone to read. Think about it, it is more optimal for the world in the long run.
Of course, Palantir is behind this. Someone should really start putting checks on Silicon Valley executives, especially Peter Thiel.
Re:The Oversimplification of Results and Hard Work on Monday January 15, 2018 @03:45PM (#16153272)
No. I simply pointed out that someone with sufficiently high intellect would have found other ways to get a job. Unless she is a statistical anomaly people in her situation would have similar experiences. I see no evidence that she was particularly unlucky, and even if she was ― bad things happen to people all the time.

The central point I was trying to make was that hard work pays off, if you are smart enough.

For example, Jeff Dean currently heads Google Brain despite having not having a PhD in machine learning (his PhD was on whole program optimization of object oriented languages). Or John Carmack starting Armadillo Aerospace would be another example.

I expect to be downvoted again, but I stand by what I said.

Re:The Oversimplification of Results and Hard Work on Monday January 15, 2018 @01:17PM (#16152288)
__I am average at my studies, what seemed to be super easy to my peers seemed strenuous for me.__

This is probably going to controversial, but her core problem seems to be an insufficiently high g-factor. She could have contributed to a prominent open source project like the Linux kernel or the C++ compiler. The only barriers to entry are technical competency and ability to focus.

__Hard work has been overly simplified to “If you work hard, you will achieve your dreams.”__

This is true assuming your dreams are calibrated to your capabilities. I presume the problem was her map was not in sync with the territory. Elon Musk can dream about going to Mars. I can't because I simply lack the willpower/drive/intelligence to achieve that.

We need to stop perpetuating the egalitarian fantasy. All men are not created equal.

In general, the FDA over-regulates rather than under regulates.

A comment is too short to summarize the reasons why, but I would refer interested people to Eliezer Yudkowsky's Inadequate Equilibria ― there is a 50 page dialogue between two humans and an alien visitor on the FDA.

Dell XPS 15. Dell laptops have by far the best support for Linux.

Ask HN: Is Tinder-like networking based on shared interests a good idea?

I've met very few people whose interests/hobbies overlap with mine in the real world. The specific problem I have is that all my interests are either too obscure or technical.More generally, it seems like in 2018 I should be able to find and make friends online (if we are compatible mentally). More specifically, right now you need to be "locally" present and meet in person for friendship to...

( Read More... | 1 comment | 2 points | on HN )
Re:Today is the fifth anniversary of Aaron Swartz's death on Thursday January 11, 2018 @07:25AM (#16123219)
His blog Raw Thought (http://www.aaronsw.com/weblog/) details his experiences. I found his memoirs about Stanford particularly interesting. An example entry:

""" Surrounding them were groups of kids chatting. Clearly social rituals depend on communication, which is presumably used to get a sense of the kind of person the other is. In my culture (of vaguely technical people), people converse by sharing information through mutually-beneficial discussion and debate, but the teenager's system is altogether different and wholly alien to me.

I have little firsthand experience, but I have developed an initial theory of how things work. The protocol begins by sharing basic personal information to establish identity, then moves to the humorous recitation of cultural information. (Humorous may be too strong a word; the key point is that there's a lot of laughing.) This is the beginning of a loop. The two parties exchange information, allowing them to get a better sense of each other. If the clearer picture is disliked, the party breaks the loop and disassociates. Otherwise, more personal knowledge is shared as the parties get to know each other better. Discussion moves from cultural issues, to societal ones, to gossip, to personal matters, to deep intimate issues, presumably shared with close lovers or friends. """ ― http://www.aaronsw.com/weblog/001421

Try Terence Tao's Analysis I and II.
Re:The Foundations of Mathematics (2007) [pdf] on Friday January 05, 2018 @11:04AM (#16079390)
I wouldn't say it "challenges" set theory.

For this to be the case there have to demonstrable advantages over working with set theory. The main attraction of HoTT is that it allows people to do homotopy theory on computers using theorem provers. It is still a very open question whether this is an improvement over pen and paper math. It's still not clear if HoTT is just some neat technical gimmick that allows one to model homotopy theory using type theory.

This is still certainly worth investigating, but saying that HoTT "subsumes" set theory is a bit strong.

I would refer the interested reader to the discussion at https://mathematicswithoutapologies.wordpress.com/2015/05/13... (between Jacob Lurie, Shulman and Voevodsky).

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