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A from-scratch tour of Bitcoin in Python

karpathy.github.io

241–250 of 293 posts

Re: A from-scratch tour of Bitcoin in Python

#241

Earlier quoted context omitted.

Bitcoin doesn't scale. https://digiconomist.net/bitcoin-energy-consumption Just watch this video: https://www.youtube.com/watch?v=UDKntG4F0hg So in about 5 years pretend everyone in the United States melts a wrench like that... Then a month later they do that twice, a month later they do it three times. Hey, at least it will be fun.

Why does every discussion about Bitcoin's environmental impact reduce to "it uses a lot of electricity therefore it should be stopped". We're not going to shut down entire sectors of the economy because of their environmental impact. People are going to innovate and invest in alternative sources of energy because it is becoming profitable to do so. The solution is hardly ever "just stop doing it", it's "how can we do…

Crypto is hardly a "sector of the economy". It's main utility right now is lining the pockets of a few speculators.

Traditional centralized ledgering systems do everything crypto does better and with a fraction of the energy use. It also gives governments tools to combat inflation/deflation and manage counterparty risks within the system.

Crypto is a neat idea, but in the end it doesn't really solve anything, and instead only introduces a lot of unnecessary problems.

Re: A from-scratch tour of Bitcoin in Python

#242

Earlier quoted context omitted.

Bitcoin doesn't scale. https://digiconomist.net/bitcoin-energy-consumption Just watch this video: https://www.youtube.com/watch?v=UDKntG4F0hg So in about 5 years pretend everyone in the United States melts a wrench like that... Then a month later they do that twice, a month later they do it three times. Hey, at least it will be fun.

Why does every discussion about Bitcoin's environmental impact reduce to "it uses a lot of electricity therefore it should be stopped". We're not going to shut down entire sectors of the economy because of their environmental impact. People are going to innovate and invest in alternative sources of energy because it is becoming profitable to do so. The solution is hardly ever "just stop doing it", it's "how can we do…

There are few sectors of the economy whose entire model depends fundamentally on huge energy consumption: Bitcoin's Proof of Work depends entirely on wasting huge amounts of electricity as assurance that transactions are verified. If mining became more power efficient, the algorithm would be changed to bring it back to where it is today.

Re: A from-scratch tour of Bitcoin in Python

#243
post #24

I'm amazed that he has time for this kind of hobby work.

I think he’s a natural teacher - someone who loves sharing what he’s learnt with others - and it pleases to me know such people exist.

Everything I learned about deep neural networks, enough to apply it in a live product, was essentially all his notes, videos and exercises. And it’s all out there for free!

Thanks Andrej and keep doing cool stuff!

Re: A from-scratch tour of Bitcoin in Python

#244
post #61

"...Bitcoin is a living, breathing, developing code base that is moving forward with new features to continue to scale..." There is exactly zero progress to make it scale in the last 10+ years.

There was never any need to scale it at the protocol level. The overwhelming majority of Bitcoin transfers presently happen off-chain, within exchanges. Very few people seem to understand this.

I don't understand. How do Bitcoin transfers happen off-chain? Are those Bitcoin transactions that don't actually use the blockchain?

Re: A from-scratch tour of Bitcoin in Python

#245
post #238

Earlier quoted context omitted.

I wish this were talked about more. Quantum computing is the biggest long-term threat to crypto imo. What's the plan once elliptic curve cryptography can be broken? There will be a point in time where there are just a few quantum computers that can break everything before the general public has access to quantum computing. Can crypto work in that scenario? Normal computers wouldn't be able to work with the beastly al…

We already have a solution ( https://en.wikipedia.org/wiki/Lamport_signature ) but there’s no reason to deploy it yet since it reduces scalability.

The problem with "yet", in security, is that by the time you realize that "yet" is here, it's already too late.

Re: A from-scratch tour of Bitcoin in Python

#246

Earlier quoted context omitted.

He was doing this kind of hobby work well before. I learnt solving Rubik's cube from his page[0]. [0] http://badmephisto.com

Woah, he's him? Same here!

Same - recognised the domain instantly! Used it to teach my son as well.

Re: A from-scratch tour of Bitcoin in Python

#248
post #60

This is reminds me of Ken Shirriff's 2014 "Bitcoins the Hard Way" blog post that also used Python to build a Bitcoin transaction from scratch: http://www.righto.com/2014/02/bitcoins-hard-way-using-raw-bi... (The subtitle of the blog is "Computer history, restoring vintage computers, IC reverse engineering, and whatever" and it is full of fascinating articles, several of which have been featured here on HN)

No, the hardest way is using pencil and paper to mine a block :) https://gizmodo.com/mining-bitcoin-with-pencil-and-paper-164...

Same guy, Ken Shirriff

Re: A from-scratch tour of Bitcoin in Python

#249

Earlier quoted context omitted.

“I choose a lazy person to do a hard job. Because a lazy person will find an easy way to do it.” ― Bill Gates

Is it necessary for me to drink my own urine? No, but I do it anyway because it's sterile and I like the taste. -- Patches O'Houlihan

I am Groot

-- Groot

Re: A from-scratch tour of Bitcoin in Python

#250
post #24

I'm amazed that he has time for this kind of hobby work.

A lot of busy, smart people have seemingly random side-projects. For example, Von Neumann:

"A professor of Byzantine history at Princeton once said that von Neumann had greater expertise in Byzantine history than he did" [1]

I don't know for sure why, but I think two possibilities are likely: (1) An extremely strong, natural intellectual curiosity and/or (2) Working on other things allows them to bring fresh ideas/insights to their "main" work, and in this sense is also rejuvenating.

[1] https://en.m.wikipedia.org/wiki/John_von_Neumann

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