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sadfev

56 karma · joined February 28, 2020

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sadfev··on Moderna Is About to Begin Trials for HIV Vaccine
Easy! that’s a simple multi-objective optimization problem!
sadfev··on Kind: A Modern Proof Language
Awesome, that’s something doable and could be a good learning exercise!!
sadfev··on Kind: A Modern Proof Language
Very true. But the most popular ones are based on DTT, GP only mentioned Lean/Coq/Idris.

Indeed by sacrificing the power of type system we can augment classical axioms consistently as shown by HOL family.

These come with their own disadvantages.

sadfev··on Kind: A Modern Proof Language
Thanks for clarifying, I haven’t studied co-inductive types yet.
sadfev··on Kind: A Modern Proof Language
Isabelle is a generic proof engine, can be combined with any fronted which satisfies its API (it’s a bit more complicated) so yes such thing exists.

Proof assistants aren’t whimsical like cottage industry of programming languages. Proof assistants are divided into 3 parts, the core or foundation (F) which is a very small language at the heart of the prover, the vernacular (V) the language in which humans write the code and the meta language for proof search and meta programming (M).

The V is translated into F and this translation is often proven to be correct. De Bruin criteria says that F has to be small and should be independently checked (mostly through inspection or mechanization in other framework). In Coq the proof derives is again checked from ground up by F when you write Qed.

Andrej Bauer explains better than I can.

https://mathoverflow.net/questions/376839/what-makes-depende...

sadfev··on Kind: A Modern Proof Language
I am still very new to proof theory. So please take this with a mountain of salt.

At the core all these proof assistants, is a dependent total functional programming language.

Total means all functions must be obviously be terminating.

Dependent means types can dependent on values or more generally you can have quantifiers (sigma and pi).

Both Coq and Lean have variants of a dependent type theory called “Calculus of Inductive Constructions”.

Coq and Lean have tactics which can be thought of an embedded “proof language”. It’s an useful fiction because underneath it is just functions and inductive definitions.

Agda and Idris doesn’t have tactics, so the proofs have to be done through computation (by defining and apply functions and data types)

Lean and Coq differ in how they encode mathematical objects. Lean makes it much easier to make use of classical axioms. (Defining axioms is easy in both Lean and Coq)

From a more practical POV, Coq has the best documentation, books and development tools.

Lean has the WORST development tools of all 4. However has extensive libraries for mathematics. ( It is very painful to use )

Agda and Idris are about the same (set up is a pain otherwise about as good as Haskell development)

Even though Idris is marketed for “practical programming” it doesn’t have partial functions!!

I am not sure if Agda supports partial functions.

A more thorough comparison can be found here : https://artagnon.com/articles/leancoq

sadfev··on Endangered Iberian lynx population jumps 10-fold
Still only 1100 exist in the wild.

Their equilibrium population was over 100000!

sadfev··on China's Baidu to launch paid driverless ride-hailing services in Beijing
Tesla’s is more viable technically and more scalable, except the problem is that system is laughably unusable in scenarios where it is needed. I have looked at so many FSD beta videos, in most of the disengagement’s the car would have crashed and burned, very badly.

I don’t think any sane regulator would ever approve such a system.. ever. The improvements are still too slow and corner cases still deadly.

On the hand the geo-fenced systems like Waymo, Baidu etc, might be difficult to scale are orders of magnitude safer. Perhaps better overall both short and long/term.

Yes I don’t know either but that’s my unconsidered opinion.

sadfev··on Microsoft revokes MVP status of dev who complained about request to promote
That’s not enough $ for that honestly
sadfev··on “They introduce kernel bugs on purpose”
Dang, I am not sure how to feel about this kind of “research”
sadfev··on Small cities in America’s Mountain West are booming
Depends on the brand, good organic milk is worth it. Bare minimum is Whole Foods 365 brand

In New England Organic Valley is as good as it gets for store milk,

https://www.cornucopia.org/scorecard/dairy/

sadfev··on Yahoo Answers to shut down May 4, 2021
No! They were such a cesspool and also internet history!
sadfev··on SBCL 2.1.3 Released
How is clisp better? Isn’t SBCL the most advanced lisp compiler, not just Common Lisp.

I thought clisp was maintained just to keep building Maxima

sadfev··on A Brief History of the Hedge Fund
Why would anyone give more fee to basically perform like market but for less volatility?
sadfev··on How Big Tech Is Importing India’s Caste Legacy to Silicon Valley
If you are an IITian and still casteist then something is wrong with you!

Look IITians are often entitled, opinionated and in rare cases obnoxious.

But never during my 5 years in IIT KGP, I have ever felt casteism among students and even amongst alumni after that.

Initially during freshman year there’s a slight sense of resentment against quota (affirmative action for lower castes) students but all of that evaporates as quota and non-quota students alike progress.

The whole point of getting advanced degrees is to shed the ignorance and discrimination and pursue what’s interesting, work with the brightest and of course make a better life for oneself.

Being casteist and discriminatory doesn’t take anyone far in life.

I really hope reports like these are media exaggerations and entitled casteist are very very few.

I have worked my whole life to ascend over this garbage. I don’t want this stupid discourse to follow me now!

sadfev··on We Expect 300k Fewer Births Than Usual This Year in the US
What a wonderful “problem” to have. That means less UBI, more advances in automation and more impulse to productivity.

No one wants to live in an overpopulated hellhole (aka India).

This should be lauded!

sadfev··on India’s new intermediary liability and digital media laws will harm the internet
Govt shouldn’t but they would want to.

The foreign social media sites have political agenda blatantly well “foreign”.

Media houses are strictly regulated and have to abide much stringent criteria for reporting or an oped.

It’s about control it was in the best interest of these tech firms to be “neutral” before they captured the entire public discourse space. That is clearly not the case now, They have infinitely more power than they had before and even more power than the sovereign government in many many countries.

Some governments are trying to protect their (digital) sovereignty through regulation.

sadfev··on Brave buys a search engine, promises no tracking, no profiling
Brendan Eich is doing some very important work. I hope this succeeds!
sadfev··on United B772 at Denver on Feb 20th 2021, engine inlet separates from engine
This could have gotten so bad so fast. Well trained pilots, arc, decent protocols and some luck saved 231 lives here!
sadfev··on I am a heroin user. I do not have a drug problem
Yeah, all drugs should be allowed. Just have sane programs for sanitary usage and perhaps a small tax on users so that the peripheral facilities can be run without taxing wider population.

If one (adult) can’t handle drugs then help should be readily available as is for alcoholics.

No need to get political and emotional about it, there’s a pragmatic way.

sadfev··on Fitbit is now officially part of Google
Anti-Trust investigation should break Alphabet to million pieces. Way too many big tech apologists here.
sadfev··on Amazon, Apple and Google Cut Off Parler
I think this should incentivize people to build their own backend and definitely move off big tech cloud. I know it’s more expensive but it was routine in 90s and 00s
sadfev··on SEC Approves NYSE’s Plan for New IPO Alternative
This is great. These banks/middleman are less relevant.
sadfev··on Tesla Mania vs. Economic Reality
Yet another hit piece. These stupid media puppets are in the business corrupt practice of writing hit pieces for a cozy profit no matter who funds them.

They (Big Fossil) are not evil as long as they pay these “media” houses cozy bribe.

sadfev··on Firefox Was Always Enough
No, all your pandering and political posturing doesn’t mitigate the fact that FF is a hot pile of usability garbage
sadfev··on Indian iPhone Factory Attacked by Angry Workers
That is the greatest tragedy of India. This is the main reason India is destined to be a perpetually poor country not even a middle income country.

It’s mob rule at it’s most vicious.

sadfev··on EU countries team up for semiconductor push
Government incompetence at the highest level!
sadfev··on We Love GPLv3, but Are Switching License to Apache 2.0
It’s great that you welcome a GPL fork, perhaps there is room for one.
sadfev··on Justice Department Sues to Block Visa's Proposed Acquisition of Plaid
To a certain extent, it is detrimental if the prices are lower than the transaction expenses. Because you have to pay indirectly which is even worse
sadfev··on Colombia is considering legalizing its cocaine industry
Let’s make everything legal!!
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