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espeedon Fake it till you make it: the wolves of Instagram

Buffett's field of study is the finance and economic system.

It should be easy to see that one of the things that separates Warren Buffett from the rest of us is that he has a unique perspective of the financial world – he sees all of the dynamics and intricacies of the financial world in a way that few others do.

It took years for him to build the mental framework that led to his deep understanding and unique view of the world. And as a result of his devotion to this pursuit and his willingness to immerse himself in it, he developed the structural underpinning for the mental vista that yields the rare and valuable perspective that enables him to see the financial world with the clarity of a composer likely unattained by anyone in history.

This is why Goldman Sachs calls him when they need help, like they did in the financial crisis.

espeedon The Dozenal Society of America

Similarly, see Pavel Grinfeld's argument [2] advocating the vector basis L = {1, x, x²-1/3} w.r.t. Legendre polynomials.

[1] https://en.wikipedia.org/wiki/Pavel_Grinfeld

[2] MathTheBeautiful: Why {1,x,x²} Is a Terrible Basis [video] https://www.youtube.com/watch?v=pYoGYQOXqTk&index=14&list=PL....

[3] https://en.wikipedia.org/wiki/Legendre_polynomials

espeedon Elevated Use of Absolutist Words Is a Marker of Anxiety, Depression [pdf]

Oh well, dammit. I see that now. It's a zero-sum game, and in first-to-market, winner takes all. Time to pivot.

espeedon The conceptual origins of Maxwell's equations and gauge theory (2014) [pdf]

Note the article is by Nobel Laureate C.N. Yang [1] who also worked with James Simons and co-authored what has become known as the "Wu-Yang Dictionary" [2].

[1] Yang-Mills Theory: https://en.wikipedia.org/wiki/Yang%E2%80%93Mills_theory

[2] "Wu-Yang Dictionary" http://www.indiana.edu/~jpac/QCDRef/1970s/Concept%20of%20non...

...The mathematics of these results is in fact well known to the mathematicians in fiber bundle theory. An identification table of terminologies is given in Sec. V. We should emphasize that our interest in this paper does not lie in the beautiful, deep, and general mathematical development in fiber bundle theory. Rather we are concerned with the necessary concepts to describe the physics of gauge theories. It is remarkable that these concepts have already been intensively studied as mathematical constructs.

"Gauge Theory and Inflation: Enlarging the Wu-Yang Dictionary to a unifying Rosetta Stone for Geometry in Application" https://www.youtube.com/watch?v=h5gnATQMtPg

espeedon Elevated Use of Absolutist Words Is a Marker of Anxiety, Depression [pdf]

Definitely. "Never say never. Always give it your all. It's all or nothing." Everyone constantly says these things all of the time, but it's totally untenable. Besides being harmful, it's completely cliche. It's time everyone comes to terms with it. It's the subtle things that kill ya. Everything must be reexamined and reworked -- a complete and full examination of our entire vocabulary -- every jot and tittle. A massive undertaking yes, but we must. Let's face it, we need whole-scale change. Change is the only constant, and it's now or never. We must all pledge to absolutely never ever say these things again. Ever.

espeedon Show HN: How to store a set of four 5-bit values in one 16-bit value

De Brujin Sequences

espeedon Google Chromecast and Google Home Causes Wi-Fi Drops

Indeed, my Ubiquiti Unifi AP and Edge router have also been handling the mass influx of Chromecast and Google Home devices in my house - there's one of each in almost every room in addition to the slew SmartTVs of Android devices sitting around the house -- prob at least 5 pairs of Chromecast & Google Home devices (10 total) and prob at least 30 devices in total connected to that AP full time. Over Christmas when the entire family was here there was prob double that (60 total), including all the new devices received as gifts that were connecting to the AP for the first time all at once as people were playing with and configuring the new devices they got. The Ubiquiti wifi AP and router handled it without a blink.

HOWEVER, over the last few weeks I suddenly started experiencing continual wifi drops on my Fedora 26 and 27 desktop workstation. At first I thought it was related to an overflow of devices and/or a noisy channel, but it turned out not to be the case. None of the Chromebooks or other devices were experiencing frequent wifi drops so then I thought it might be related to my workstation wifi card antenna flaking out and causing the signal to weaken and drop. It turned out the issue was also not due to a failing wifi card. It took me at least a week to isolate and resolve the issue, but it's fixed now -- no more wifi drops and the signal is strong -- turns out it was a software issue with the more or less default Fedora 26 and 27 wifi config that I had been running for years. The issue might have been exacerbated by the increased Chromecast and Google Home devices on the network, but the issue wasn't because the devices were overloading the router or AP like I (and I presume others) initially thought.

When I have time, I'll go back through my logs and command history, and distill the resolution procedure into a gist.

espeedon How many reversible integer operations do you know?

Scott Aaronson, Daniel Grier, and Luke Schaeffer did a paper on this a few years back...

The Classification of Reversible Bit Operations https://www.scottaaronson.com/papers/gates.pdf

Grier's ITCS presentation on it https://www.youtube.com/watch?v=egU5JLbpmkA

BTW see Lehmer codes for permutation sequences https://en.wikipedia.org/wiki/Lehmer_code (no relation to Lemire ;)

espeedon Your Mind Is Eight-Dimensional – How Algebraic Topology Is Unlocking [video]

~>> E8 ?

espeedon H3: A Hexagonal Hierarchical Geospatial Indexing System

Isn't the prevailing wisdom to skip 3-space and go directly to 4-space, which makes things even simpler and more powerful -- note 4D projective space (homogeneous coordinates, not quaternions and not counting a time dimension).

Reasons for going to 4D are numerous and varied, such as symplectic geometry only works in even dimensions, image/video reconstruction, matrix multiplication, transformations, and other reasons related to computer vision, gauge theory, and topology.

espeedon Your Mind Is Eight-Dimensional – How Algebraic Topology Is Unlocking [video]

Here's the referenced journal article...

"Cliques of Neurons Bound into Cavities Provide a Missing Link between Structure and Function"

https://www.frontiersin.org/articles/10.3389/fncom.2017.0004...

NB: The supplementary material PDF has graphs showing dimensions 0 through 7 (note the zero-based indexing so that's 8 total dimensions). https://www.frontiersin.org/article/10.3389/fncom.2017.00048...

espeedon H3: A Hexagonal Hierarchical Geospatial Indexing System

Hi Andrew - You went to school for chemistry and chemical engineering. I'm still experimenting with ideas for binary codes of succinct/implicit geometric representations for similarity graph embeddings of non-spatial property data like text and numbers. I keep bumping into the crystallography literature -- the traditional lattice structures and also quasicrystal / fibonacci chain representations. How much of your chemical engineering background have influenced your designs?

espeedon H3: A Hexagonal Hierarchical Geospatial Indexing System

Also see NASA JPL's HEALPix v3...

"A multi-resolution HEALPix data structure for spherically mapped point data" (2017) http://www.heliyon.com/article/e00332

espeedon A Short Introduction to Implicit Computational Complexity [pdf]

You can see all the references listed here with hyperlinks: https://link.springer.com/chapter/10.1007/978-3-642-31485-8_...

espeedon The Foundations of Mathematics (2007) [pdf]

NB: ICYW

  (defaxiom succ
    "The successor integer."
    []
    (==> int int))

https://github.com/latte-central/latte-integers/blob/master/...

A computer language is not just a way of getting a computer to perform operations but rather that it is a novel formal medium for expressing ideas about methodology. Thus, programs must be written for people to read, and only incidentally for machines to execute. - Preface, SICP 1st Ed. https://mitpress.mit.edu/sicp/front/node3.html

espeedon The Foundations of Mathematics (2007) [pdf]

Isn't Vladimir Voevodsky's [1] Univalent Foundations [2] / Homotopy Type Theory [3] a new candidate challenging to subsume set theory as the foundations of mathematics [4]?

[1] https://en.wikipedia.org/wiki/Vladimir_Voevodsky

[2] https://en.wikipedia.org/wiki/Univalent_foundations

[3] https://homotopytypetheory.org/

[4] https://www.youtube.com/results?search_query=Vladimir+Voevod...

espeedon Emacs is available on Chromebook and Chrome

FYI: Evidently emacs on termux is the way to go, now that Chromebooks have been updated to run Android apps. https://termux.com/

espeedon Samsung’s biggest challenge now is Google software, not Apple hardware

This. It's not about the hardware anymore, it's the software, services, and security that matter now. On these fronts Google is light years beyond Samsung or Apple, and the expanse is only going to get greater over the next 10 years, esp with its data resources combined with its advances in AI. Skate to where the puck is going.

espeedon Ask HN: Does reading code actually make you a better developer?

Yes, just like reading research papers will expand your horizon and build your cognitive map, the more code you read, the more you'll see concepts and patterns repeating. You'll start to identity what's important and how things are related in sometimes subtle ways. You'll encounter the same idea expressed in different forms, in different languages. This will help reveal the essence of an idea as you begin to identify its invariants that persist from language to language and form to form. You'll see contrasts between good code and bad code. Beautiful code and ugly code. Readable vs cryptic code. Clean lines vs nesting. Your sense of style and aesthetics will refine. But don't just read code in your preferred language or domain of expertise. Learn to read code in multiple languages, in multiple paradigms. High level and low level, up and down the stack. Read to refine your thinking. You'll develop fluency, and your code will evolve.

espeedon What are some things you wish you knew when you started programming?

The Fall 2010 version of MIT 6.042J Mathematics for Computer Science is a good one (as I recall there are several versions online from different years), and someone from Google is teaching it this year (haven't heard if the videos will be made available online):

https://www.youtube.com/watch?v=L3LMbpZIKhQ&list=PLB7540DEDD...

espeedon Immersive Linear Algebra – textbook with fully interactive figures (2015)

Presumably...

Statistics 110: Probability - Joe Blitzstein, Harvard University http://projects.iq.harvard.edu/stat110/youtube

espeedon What are some things you wish you knew when you started programming?

I remember Shai from back in the ArsDigita days. ArsDigita and OpenACS were one of the first open-source projects I was involved with. Shai was one of the instructors at ArsDigita University -- one of the first CS courses on the Internet. ADuni began as an experiment by Phil Greenspun to see if it was possible to teach non-CS college grads the MIT Course 6 curriculum, compressed into a one-year, accelerated postbaccalaureate CS program.

https://en.wikipedia.org/wiki/ArsDigita

After the year ended, they released all of the video lectures online. This was back in the late 90s / early 2000s. Back then there was no YouTube, video compression sucked, and broadband was in its infancy so connections were painfully slow . To get the videos, you could try and download the massive video archive, but it took forever and I don't think I ever got the full thing. Finally at some point they started selling and shipping HDDs pre-loaded with the entire video archive.

http://aduni.org/courses/

Today we're fortunate to have a lot of high-quality course content available online. Greenspun was one of the pioneers who helped make that happen. We should all be thankful for his foresight and initiative to trailblaze that space.

http://philip.greenspun.com

Prior to ADuni, Phil put all the curriculum online for MIT 6.916 "Software Engineering for Web Applications". It was one of the first serious Web Engineering courses offered anywhere. Several other schools used the material to teach the course in their CS dept.

http://philip.greenspun.com/teaching/old-one-term-web-6916

Problem Set 4 was my favorite -- design a Knowledge Management (KM) system using metadata, and then let the computer generate the server-side code for the application automatically.

http://philip.greenspun.com/teaching/psets/ps4/ps4

The material was so new and innovative, it was the thing back in the day -- part of the foundational material programmers used as we were learning to build server-side apps in the dotcom era. The ArsDigita Community System (ACS) was one of the first big Web development toolkits, and it was built on top of AOLserver, a high-quality C server that had an embedded Tcl interpreter running inside. Greenspun is an MIT Lisp hacker, and Tcl is an embeddable language similar to Lisp. And running Tcl directly inside AOLserver was a key innovation because it made server-side scripts fast because it bypassed all the traditional CGI overhead, and it allowed you to make database calls from directly inside the server. All the architecture design choices were documented and explained in detail in "Philip and Alex's Guide to Web Publishing," which was required reading at the time.

http://philip.greenspun.com/panda/

The semester I did the self-study program, Phil had the MIT students take the final exam online via an app built on the ACS. The exam wasn't open to self-study students, but I wanted to take it for my own edification. I had become intimately familiar with the ACS code, and I found a way to to hack into the online system and took the exam under some guest account. I never found out how I did though -- I asked Phil about it one time when he came to Dallas, but he didn't remember. I can't believe that was almost 20 years ago.

espeedon What are some things you wish you knew when you started programming?

Oh BTW, I answered a similar question in a comment a few weeks back -- I had more time that day, and I was able to give a more detailed answer:

See https://news.ycombinator.com/item?id=13713199

Also I've been posting a lot on math lately so if you want more examples and references, scroll through my HN posts and comments (I tend to cite everything so there's a ton of links in there).

Of special note, as others have started to discover, Grant Sanderson's 3Blue1Brown YouTube channel is a masterwork, an evolutionary tour de force in the way mathematical concepts and visualized and presented.

Grant wrote a custom software library (in Python, on Github) that enables him to create video visualizations to show the geometrical intuition behind abstract mathematical concepts. And this is key. Being able to visualize the geometric structure and transformations the mathematics is describing is the key that's been missing from the way math is traditionally taught, and this lack of visual intuition is why many find math so hard to penetrate.

3Blue1Brown's YouTube channel : https://www.youtube.com/channel/UCYO_jab_esuFRV4b17AJtAw

Go there first to develop your visual intuition -- watch all his videos, and then watch them again, and again -- and soon you'll discover your new, powerful mental models forming, and things that were once opaque will suddenly become clear.

Start with his "Essense of Linear Algebra" series (it's one people are usually blown away by, and it's being discussed on HN a bunch lately).

He's going to release an "Elements of Calculus" series in April, and while Calculus is usually a prerequisite to Linear Algebra, it's not critical for understanding the visualizations the way it's presented here. But if you need a refresher, MIT's "Big Picture Calculus" is great (it's linked to in the HN thread I referenced in the first paragraph).

espeedon What are some things you wish you knew when you started programming?

Logic is a form a mathematics, and understanding logic is essential. Indeed, for many programmers, that's the extent of the math they know and use. And that's what limits them. There is so much more.

espeedon Immersive Linear Algebra – textbook with fully interactive figures (2015)

This time however my perspective was changed. I was approaching the subject through the lens of intuition and simplicity...And to my surprise, again and again, the difficulty was in my rigidness in understanding.

Thank you for penning those words. I hope people realize the significance of what you just said.

Perspective is key. You could say it is the KEY -- the key insight into unlocking everything else. I had a similar experience in 2009, and once you have the epiphany -- once you experience the awe of a shift and recognize the implications -- it's like your mind becomes unshackled. You realize you have been blind, and you've just learned to see. And in that flash you gain a deep, visceral understanding of what Alan Kay means when he says, "A change in perspective is worth 80 IQ points," and "We can't learn to see until we admit we are blind."

"Life's Illuminating Perspective" (2009) http://jamesthornton.com/manifesto

espeedon What are some things you wish you knew when you started programming?

See https://news.ycombinator.com/item?id=13904881

espeedon What are some things you wish you knew when you started programming?

The true language of computing is mathematics, and its power and beauty are masked to those who cannot speak it. Programming languages are powerful tools for communicating ideas and encoding the language of mathematics. You can use these tools to shovel bits around without understanding the language, but you won't be able to see or say much unless you become fluent. Creative expression comes with fluency, and fluency requires the perspective unlocked through deep understanding. Becoming fluent in the language of math is the rite of passage one must cross to receive its true potential.

https://en.wikipedia.org/wiki/Mathematics

espeedon What the CIA WikiLeaks Dump Tells Us: Encryption Works

Not exactly. The majority of local news organizations don't have the resources to investigate and report on all the events happening throughout the world and so the international wire services like AP and Reuters fill this gap. However, this means the majority of national/international stories being reported by the downstream local newspapers and media outlets throughout the nation/world come from just a few big upstream sources, like AP and Reuters. A criticism of this model is regardless of how impartial the content of the upstream stories may be, the wire services effectively select what stories get reported -- what gets attention vs what gets omitted -- out of the sea of millions of possible stories happening throughout the world each day. This puts them in position to control our window to the world -- to influence what we do and don't see -- what we're made aware of -- and thus they are in position to shape the world's perspective.

espeedon What the CIA WikiLeaks Dump Tells Us: Encryption Works

So someone reporting a message to Facebook would be the equivalent of that person (either Alice or Bob) reporting and sending the content of the other person's encrypted conversation to a third party.

The Signal Protocol provides end-to-end encryption so you don't have to trust the intermediate parties/servers involved in relaying the message (e.g. you don't have to trust Facebook's servers), and to protect against the other person reporting and revealing your conversation to someone else, the Signal Protocol provides message repudiation [1], which effectively gives the sender plausible deniability because the receiving party cannot prove to a third party that a message came from you.

[1] https://en.wikipedia.org/wiki/Signal_Protocol#Properties

espeedon What the CIA WikiLeaks Dump Tells Us: Encryption Works

The phone number is not required as per the Signal protocol -- it's an implementation detail -- another token could be used. At this time, phone number verification is used in the initial authentication flow to protect against someone else spoofing your phone number and pretending to be you.

See https://github.com/WhisperSystems/Signal-Android/issues/1181