Hacker News: slack3r

New comment by slack3r in "Proof by Contrapositive Is Wrong"

slack3r — Wed, 23 Jul 2025 10:50:21 +0000

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

slack3r — Wed, 23 Jul 2025 08:46:12 +0000

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.

Comments URL: https://news.ycombinator.com/item?id=44657020

Points: 1

# Comments: 3

How Computer Programming Feels

slack3r — Sat, 10 Feb 2024 10:16:50 +0000

Article URL: https://krez.expert/emotions/2024/02/10/linear-white.html

Comments URL: https://news.ycombinator.com/item?id=39325043

Points: 1

# Comments: 0

New comment by slack3r in "Country-Wise Living Standards for an Amazon SDE 2"

slack3r — Sat, 27 Jan 2024 07:24:32 +0000

They are living in some very tiny house. Housing is the highest expenditure present.

I calculated the rates for 111 square meters.

New comment by slack3r in "Country-Wise Living Standards for an Amazon SDE 2"

slack3r — Sat, 27 Jan 2024 06:39:52 +0000

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.

Country-Wise Living Standards for an Amazon SDE 2

slack3r — Sat, 27 Jan 2024 06:39:52 +0000

Article URL: https://docs.google.com/spreadsheets/d/15_OQQc-1BBGgFF7ihRfSuxzeH6VWwDG9panSKmQVoZ4/edit#gid=0

Comments URL: https://news.ycombinator.com/item?id=39153219

Points: 3

# Comments: 3

New comment by slack3r in "Ask HN: Leaving a Job at Big Tech Giants for Startup"

slack3r — Sun, 24 Feb 2019 17:21:31 +0000

If you have to ask, you should probably stay at Big Tech Giant.

New comment by slack3r in "Who Owns Buried Treasure?"

slack3r — Sun, 24 Feb 2019 17:18:52 +0000

IMO : If it's on private property, whoever owns the property. If it's on public property then the government.

New comment by slack3r in "Google Maps: Bird Mode"

slack3r — Sun, 24 Feb 2019 17:12:35 +0000

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/

New comment by slack3r in "Stream Ring Theory – A Turing-Complete Stream Algebra"

slack3r — Sun, 24 Feb 2019 17:04:28 +0000

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

New comment by slack3r in "Ask HN: How Would You Explain HN to a Two-Year-Old?"

slack3r — Sun, 24 Feb 2019 15:45:03 +0000

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.

New comment by slack3r in "The Cost of Abstraction (2016)"

slack3r — Sun, 24 Feb 2019 15:42:55 +0000

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".

New comment by slack3r in "Stream Ring Theory – A Turing-Complete Stream Algebra"

slack3r — Sun, 24 Feb 2019 15:39:15 +0000

Classic case of math envy. Ha ha ..

New comment by slack3r in "Ledger's Advanced Side Channel Analysis Repository"

slack3r — Wed, 20 Feb 2019 08:01:12 +0000

> 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...)

New comment by slack3r in "Flavors of SIMD"

slack3r — Wed, 20 Feb 2019 06:34:09 +0000

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

New comment by slack3r in "Flavors of SIMD"

slack3r — Tue, 19 Feb 2019 17:37:24 +0000

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

New comment by slack3r in "Flavors of SIMD"

slack3r — Tue, 19 Feb 2019 15:19:46 +0000

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!

New comment by slack3r in "Deep learning may need a new programming language"

slack3r — Tue, 19 Feb 2019 15:11:26 +0000

Yes. Deep Learning definitely needs a new programming language. Uber's Pyro is worth checking out. (https://eng.uber.com/pyro/)

New comment by slack3r in "Amazon Caught Selling Counterfeits of Publisher’s Computer Books–Again"

slack3r — Tue, 19 Feb 2019 15:03:00 +0000

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.

New comment by slack3r in "“Reverse location” search warrants identify all cellphones near a crime scene"

slack3r — Tue, 19 Feb 2019 14:59:18 +0000

Of course, Palantir is behind this. Someone should really start putting checks on Silicon Valley executives, especially Peter Thiel.