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Robᵉʳᵗ Graham😷, provocateur Profile picture
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9 Apr, 9 tweets, 2 min read
How is Musk's tunnel in Las Vegas better than a normal train tunnel.

To answer this, we are going to use what computer scientists call "big-O notation". Tunnels are 𝑶(𝑛²) -- so Musk's trick is to create narrow tunnels.
The effort to dig tunnels depends upon the size of the tunnel -- but this grows faster than you think. Twice the width of the tunnel means FOUR TIMES the effort to dig it. You can see that with the following circles: the larger is twice the width of the 4 smaller ones
Subway tunnels to fit rail cars are often around 28 feet, Elon's trying to get his tunnels below 14 feet. This means creating tunnels with ¼ the effort, a quarter of the cost. Instead of $200million for the Las Vegas project, $50million.
The point of this thread is to explain Big O notation by explaining Elon's Boring Company. He's a computer geek who understands 𝑶(𝑛²) and how to exploit that.
Of course, everyone has known about this scaling issue for a long time. So the question is really "why now?". Why do narrow tunnels make sense now where they haven't before?
The answer is ultimately the fungibility of self-driving electric cars. You had to carry humans in bulk before, for efficiency. Now you can carry humans efficiently one at a time by sticking them in a self-driving electric car shooting through the tunnel.
Elon still has some work to do on that score -- he's having human drivers in his Las Vegas demonstration, which is stupid. It's a typical example of him overpromising -- but he usually delivers, eventually.
Whelp, I guess I was wrong. Still, it's a Big O problem -- learn your Big O notation in college kids.
Also, learn your pizza math:

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More from @ErrataRob

Robᵉʳᵗ Graham😷, provocateur Profile picture
7 Apr
College programming courses are horribad. They are college -- they attempt to teach you the theory of coding rather than practice. Thus, they leave you totally unequipped to actually code.
To be a good coder you need both theory and practice, so I can't say that colleges are wrong in focusing on theory. I'm just saying that you need practice. If you enter college having already practiced, the theory will make much more sense.
If you try to learn coding by picking up a college textbook and all that theory looks like gibberish, drop it and find a book that focuses on practice instead. But later, go back to that college textbook and learn theory. Both are needed.
Read 5 tweets
Robᵉʳᵗ Graham😷, provocateur Profile picture
7 Apr
If you go back through my feed, you'll see tweets like this one. I'm rabidly pro-vaccine, but also supportive of the fact that there's two sides to the question, that instead of bullying people for questioning vaccines, we should empathize with them:
Sometimes a feel alone. All I see on my twitter feed is toxic bullying of those who have questions about vaccines -- without anybody actually answering those questions. Am I wrong? Should I be bullying instead of empathizing?

Then I see tweets like this:
Please get your covid vaccine as soon as possible. Those aren't "side effects" -- those are the "effect" of the vaccine that tricks the body into feeling sick without making it sick. So brief fatigue/headaches/mild-fever are normal right after -- it means it's working.
Read 12 tweets
Robᵉʳᵗ Graham😷, provocateur Profile picture
6 Apr
So let's explore why Tim Cook is stupid about thinking we can vote from phones. Image
To make internet voting work, you first need to have a national ID card. This is ironic because in the above interview, Tim Cook criticizes the Georgia voting law that has an ID requirement, then proposes Internet voting that needs more of an ID requirement. Image
Online banking works because banking tracks every transaction back to the user. The principle of voting is that you cannot track votes back to the person who cast them. Voting is anonymous: you can track the fact people voted, but not who they voted for.
Read 11 tweets
Robᵉʳᵗ Graham😷, provocateur Profile picture
2 Apr
For you data junkies: the raw data on how the recent flu season went:
apps.who.int/flumart/Defaul…
I interpret this as answering the question whether all this mask wearing, social distancing, and lockdowning actually works to stop the spread of disease. I think the answer is conclusively that it does.
I interpret this as answering the question whether the covid was no worse than the flu. This shows that the covid was wildly more infectious than the flu.
Read 6 tweets
Robᵉʳᵗ Graham😷, provocateur Profile picture
2 Apr
This.
First, find people of your same level to hang around with, that can explain things in your own terms (experts explaining things over your head really sucks).

Second, get a Raspberry Pi.
Start "sysadmining" the Raspberry Pi. Find fun projects. At some point, start playing around with networking on it. Explore all the fun command-line tools, like 'traceroute'. Use 'openwrt' as your home router and "netadmin" that heck out of that.
Now install web services on your RPi and play around with that, watching how your web server can serve raw HTML containing CSS and JavaScript. Create your own website. Now buy a domain name and push out to an AWS server. Make a LAMP app that serves stuff from an SQL database.
Read 9 tweets
Robᵉʳᵗ Graham😷, provocateur Profile picture
1 Apr
Money laundering is not a real issue in tech.

Orwellian surveillance of citizens' every financial transaction is the problem in tech. That's why there will never be cash currency greater than $100 bills -- to prevent large anonymous transactions that gov can't surveill.
It's like how Eliot Spitzer got caught "structuring" payments to prostitutes to avoid detection. The crime wasn't paying for sex, the felony was evading government surveillance.
The heavy cost of surveillance makes it nearly impossible for Americans to get bank accounts overseas. Even simple exchange students find enormous hurdles getting foreign bank accounts.
Read 8 tweets

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