Yitang Zhang's theorem by Ciro Santilli 35 Updated +Created
There are infinitely many primes with a neighbor not further apart than 70 million. This was the first such finite bound to be proven, and therefore a major breakthrough.
This implies that for at least one value (or more) below 70 million there are infinitely many repetitions, but we don't know which e.g. we could have infinitely many:
or infinitely many:
or infinitely many:
or infinitely many:
but we don't know which of those.
The Prime k-tuple conjecture conjectures that it is all of them.
Also, if 70 million could be reduced down to 2, we would have a proof of the Twin prime conjecture, but this method would only work for (k, k + 2).
Trust (law) by Ciro Santilli 35 Updated +Created
Meet-in-the-middle algorithm by Ciro Santilli 35 Updated +Created
Video 1.
The algorithmic trick that solves Rubik's Cubes and breaks ciphers by polylog (2022)
Source.
Avatar (franchise) by Ciro Santilli 35 Updated +Created
Scientific software by Ciro Santilli 35 Updated +Created
Web crawling by Ciro Santilli 35 Updated +Created
Open web crawling by Ciro Santilli 35 Updated +Created
Common Crawl by Ciro Santilli 35 Updated +Created
Amazing project, that basically makes a more searchable Wayback Machine.
A bit hard to use their data though, partly due to size, but also lack of free to use querrying mechanisms, and how obtuse Amazon S3 is to use.
Notably, aws-cli with an account is the only reliable way, everything else is way too broken, e.g. trying the to check the an index index.commoncrawl.org/CC-MAIN-2023-06/ very often 500s.
But still, their projct is amazing.
The only out-of-the-box search they seem to have is: urlsearch.commoncrawl.org/ for domains/URLs. It is good, but there could be so much more... notably IPs.
Also could should document the data shape a bit better.
To explore the data, after login:
aws s3 ls s3://commoncrawl/crawl-data/CC-MAIN-2013-20/
Copy the toplevel directory only:
aws s3 cp s3://commoncrawl/crawl-data/CC-MAIN-2013-20/ . --recursive --exclude "*/*"
Copy some wet/wat files:
aws s3 cp s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/wat/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.wat.gz .
aws s3 sync s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/wet/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.wet.gz .
Directory structrure:
  • cc-index.paths.gz (1K)
  • cc-index-table.paths.gz (1K)
  • segment.paths.gz (1.7K) Sample lines:
    crawl-data/CC-MAIN-2013-20/segments/1368696381249/
    crawl-data/CC-MAIN-2013-20/segments/1368696381630/
  • index.html (2.3K)
  • wat.paths.gz (98K) Sample lines:
    crawl-data/CC-MAIN-2013-20/segments/1368696381249/wat/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.wat.gz
    crawl-data/CC-MAIN-2013-20/segments/1368696381249/wat/CC-MAIN-20130516092621-00001-ip-10-60-113-184.ec2.internal.warc.wat.gz
  • wet.paths.gz (98K) Sample lines:
    crawl-data/CC-MAIN-2013-20/segments/1368696381249/wet/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.wet.gz
    crawl-data/CC-MAIN-2013-20/segments/1368696381249/wet/CC-MAIN-20130516092621-00001-ip-10-60-113-184.ec2.internal.warc.wet.gz
  • warc.paths.gz (99K)
    crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz
    crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00001-ip-10-60-113-184.ec2.internal.warc.gz
  • segments: directgory with actual data
    • 1368696381249: one of many segments, any meaning of name?
      • CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.wet.gz (142M, 334M unzipped)
        A tiny bit of metadata, and then plaintext content from the website, e.g. the second one:
        WARC/1.0
        WARC-Type: conversion
        WARC-Target-URI: http://004eeb5.netsolhost.com/stephensilver.htm
        WARC-Date: 2013-05-18T08:11:02Z
        WARC-Record-ID: <urn:uuid:773b31ba-ddc6-47a5-ae24-d08141b9944d>
        WARC-Refers-To: <urn:uuid:4b1bdbff-4926-4ced-86f6-072f5bb3837a>
        WARC-Block-Digest: sha1:LQFSCR2LIJQYMPTXRHWU7HAPQTVSYS3A
        Content-Type: text/plain
        Content-Length: 12046
        
        Stephen Silver is a journalist and editor who specializes in the areas of politics, pop culture, film and sports. He works as an editor with the North American Publishing Co. and as a film critic with The Trend, a local newspaper in the Philadelphia area.
        No IP unfortunately.
      • CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.wat.gz (329M, 1.4G unzipped)
        A lot of JSON metadata and no contents as desired. Contains IP! Some entries however are humongous with a ton of useless data, that's what bloats these so much:
        WARC/1.0
        WARC-Type: metadata
        WARC-Target-URI: CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz
        WARC-Date: 2013-11-22T14:51:12Z
        WARC-Record-ID: <urn:uuid:ec54e493-8965-41be-b344-07596cc30b3a>
        WARC-Refers-To: <urn:uuid:cfeff436-7c4c-4119-aaa4-ec2ce27ad3e1>
        Content-Type: application/json
        Content-Length: 1180
        
        {"Envelope":{"Format":"WARC","WARC-Header-Length":"274","Block-Digest":"sha1:JCZOI4V3UOTXGIRLFMPLW4J2WPLAKGVR","Actual-Content-Length":"372","WARC-Header-Metadata":{"WARC-Type":"warcinfo","WARC-Filename":"CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz","WARC-Date":"2013-11-22T14:51:12Z","Content-Length":"372","WARC-Record-ID":"<urn:uuid:cfeff436-7c4c-4119-aaa4-ec2ce27ad3e1>","Content-Type":"application/warc-fields"},"Payload-Metadata":{"Trailing-Slop-Length":"0","Actual-Content-Type":"application/warc-fields","Actual-Content-Length":"372","Headers-Corrupt":true,"WARC-Info-Metadata":{"robots":"classic","software":"Nutch 1.6 (CC)/CC WarcExport 1.0","description":"Wide crawl of the web with URLs provided by Blekko for Spring 2013","hostname":"ip-10-60-113-184.ec2.internal","format":"WARC File Format 1.0","isPartOf":"CC-MAIN-2013-20","operator":"CommonCrawl Admin","publisher":"CommonCrawl"}}},"Container":{"Compressed":true,"Gzip-Metadata":{"Footer-Length":"8","Deflate-Length":"453","Header-Length":"10","Inflated-CRC":"866052549","Inflated-Length":"650"},"Offset":"0","Filename":"CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz"}}
        
        WARC/1.0
        WARC-Type: metadata
        WARC-Target-URI: http://%20jwashington@ap.org/Content/Press-Release/2012/How-AP-reported-in-all-formats-from-tornado-stricken-regions
        WARC-Date: 2013-05-18T05:48:54Z
        WARC-Record-ID: <urn:uuid:d519658f-7a63-46c1-849b-4cd92332ddb8>
        WARC-Refers-To: <urn:uuid:cefd363b-1fec-4590-8305-4c6fab2e095f>
        Content-Type: application/json
        Content-Length: 1501
        
        {"Envelope":{"Format":"WARC","WARC-Header-Length":"433","Block-Digest":"sha1:B2B6JDSGWCUQIIUGV54SXEE25RX4SANS","Actual-Content-Length":"302","WARC-Header-Metadata":{"WARC-Type":"request","WARC-Date":"2013-05-18T05:48:54Z","WARC-Warcinfo-ID":"<urn:uuid:cfeff436-7c4c-4119-aaa4-ec2ce27ad3e1>","Content-Length":"302","WARC-Record-ID":"<urn:uuid:cefd363b-1fec-4590-8305-4c6fab2e095f>","WARC-Target-URI":"http://%20jwashington@ap.org/Content/Press-Release/2012/How-AP-reported-in-all-formats-from-tornado-stricken-regions","WARC-IP-Address":"165.1.125.44","Content-Type":"application/http; msgtype=request"},"Payload-Metadata":{"Trailing-Slop-Length":"4","HTTP-Request-Metadata":{"Headers":{"Accept-Language":"en-us,en-gb,en;q=0.7,*;q=0.3","Host":"ap.org","Accept-Encoding":"x-gzip, gzip, deflate","User-Agent":"CCBot/2.0","Accept":"text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8"},"Headers-Length":"300","Entity-Length":"0","Entity-Trailing-Slop-Bytes":"0","Request-Message":{"Method":"GET","Version":"HTTP/1.0","Path":"/Content/Press-Release/2012/How-AP-reported-in-all-formats-from-tornado-stricken-regions"},"Entity-Digest":"sha1:3I42H3S6NNFQ2MSVX7XZKYAYSCX5QBYJ"},"Actual-Content-Type":"application/http; msgtype=request"}},"Container":{"Compressed":true,"Gzip-Metadata":{"Footer-Length":"8","Deflate-Length":"455","Header-Length":"10","Inflated-CRC":"453539965","Inflated-Length":"739"},"Offset":"453","Filename":"CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz"}}
        Let's beautify one of them to see it better:
        
        {
          "Envelope": {
            "Format": "WARC",
            "WARC-Header-Length": "274",
            "Block-Digest": "sha1:JCZOI4V3UOTXGIRLFMPLW4J2WPLAKGVR",
            "Actual-Content-Length": "372",
            "WARC-Header-Metadata": {
              "WARC-Type": "warcinfo",
              "WARC-Filename": "CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz",
              "WARC-Date": "2013-11-22T14:51:12Z",
              "Content-Length": "372",
              "WARC-Record-ID": "<urn:uuid:cfeff436-7c4c-4119-aaa4-ec2ce27ad3e1>",
              "Content-Type": "application/warc-fields"
            },
            "Payload-Metadata": {
              "Trailing-Slop-Length": "0",
              "Actual-Content-Type": "application/warc-fields",
              "Actual-Content-Length": "372",
              "Headers-Corrupt": true,
              "WARC-Info-Metadata": {
                "robots": "classic",
                "software": "Nutch 1.6 (CC)/CC WarcExport 1.0",
                "description": "Wide crawl of the web with URLs provided by Blekko for Spring 2013",
                "hostname": "ip-10-60-113-184.ec2.internal",
                "format": "WARC File Format 1.0",
                "isPartOf": "CC-MAIN-2013-20",
                "operator": "CommonCrawl Admin",
                "publisher": "CommonCrawl"
              }
            }
          },
          "Container": {
            "Compressed": true,
            "Gzip-Metadata": {
              "Footer-Length": "8",
              "Deflate-Length": "453",
              "Header-Length": "10",
              "Inflated-CRC": "866052549",
              "Inflated-Length": "650"
            },
            "Offset": "0",
            "Filename": "CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz"
          }
        }
        Fuck no IP addresses either. But other entries do have it, why not this one?
        The reason these can be huge is the HTML-Metadata section which contain all outlinks! gist.github.com/Smerity/e750f0ef0ab9aa366558#file-bbc-pretty-wat-L34
      • CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz ()
        Obtain:
        aws s3 cp s3://commoncrawl/crawl-data/CC-MAIN-2013-20/segments/1368696381249/warc/CC-MAIN-20130516092621-00000-ip-10-60-113-184.ec2.internal.warc.gz .
Hacker group by Ciro Santilli 35 Updated +Created
Documentation generator by Ciro Santilli 35 Updated +Created
Apache License by Ciro Santilli 35 Updated +Created
GNU General Public License by Ciro Santilli 35 Updated +Created
Cutout (espionage) by Ciro Santilli 35 Updated +Created
Application of systems of linear equations by Ciro Santilli 35 Updated +Created
No 2x2 examples please. I'm talking about large matrices that would be used in supercomputers.
System of linear equations algorithm by Ciro Santilli 35 Updated +Created
University is broken by Ciro Santilli 35 Updated +Created
You just have to spend a few minutes with students until they complain about the courses or teachers. And you just have to spend a few hours with teachers until they complain about the students or broader system.
University is broken, and everyone knows it. The only question now is finding a viable, "political cash flow positive" path, into something better.
Bibliography:
University should focus on inspiring and not on evaluating by Ciro Santilli 35 Updated +Created
As of 2020s and much earlier, Ciro Santilli believes that undergrad studies were fundamentally broken (considering the Information Age which completely changed what would be possible) because university had only two goals, with the exception of a few enlightened professors:
  • rank students from worse to best so they can get into PhD programs.
    For regular jobs grades didn't even matter as much compared the prestige of your university (and therefore, university entry exam grades) and your ability to stand the stress of exams to get minimal passing grade.
    In particular, being able to rank requires setting the difficulty level at a point where you can see a normal distribution in grades, and not have everyone at either 0 nor 100%.
    Also, this split could be caused by either shitty learning materials/conditions, or by mere volume. It doesn't matter.
  • get money from the students. Of course, in countries where university is "free", this means reporting how many students you had to some government office so they can give you a corresponding budget. But you still have an incentive to enroll as many as possible.
As a result, most students, who would not go on to do a PhD essentially do a simple trade: all their time, and possibly some money, in exchange for embuing themselves with the incredible name of a respected institution so they can get better jobs later on.
Beauty, deep understanding, and learning awesome things comes basically as a second thought.
Adjacency list by Ciro Santilli 35 Updated +Created
Ordered and unordered trees by Ciro Santilli 35 Updated +Created

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