The first problem with your submission is that you submitted an incorrect URL that doesn't point to that page.

If a story has had significant attention on HN in the last year or so, we kill reposts as dupes. When posting, you should first check HN Search: https://hn.algolia.com/?q=timeline+of+the+far+future#!/story.... As you can see, it appeared in the last year. I think 23 points counts as significant, especially since there was a huge thread the year before.

Coincidentally, we updated the HN FAQ last night to answer this question.

Finally, please re-read the HN guidelines. Questions like this aren't supposed to be posted to HN itself. You should email hn@ycombinator.com.

I apologize. Thanks for the explanation.

Just gave the HN guidelines a thorough (and much needed) read.

> Just gave the HN guidelines a thorough (and much needed) read

Music to my ears!

It bothers me as an older user(six years) because I see a lot of the same links. (Good lord the number of times certain Feynman articles get published is just too much—and I'm a fan that used to study physics!)

Lately though, this has seemed like less of a problem, so I wonder if something was adjusted in the HN ranking sort.

This is a bug, a difficult to solve bug. The server don't canonize the url, so you have: "http" vs "https", "example.com" vs "www.example.com", "example.com/whatever" vs "example.com/whatever/", "blogspot.com" vs blogspot.co.uk" vs ... , ...

The problem is that canonization is very difficult, it's very easy to get false positives, and each site needs a slightly different canonization rules. So the current method is to use manual moderation.

And when the server restarts, it forgets the old url's for a while, so there are some possible repetitions.

And in a very few times, resubmissions are good.

Most of the resubmissions are accidental, good faith resubmissions. Someone just copy the url and the browser / link / site internationalization was different.

I think there are not official rules, but the unofficial algorithm is:

* When a submission was recently discussed, and it's resubmited the moderators may kill it.

* If the discussion was a long time ago, the resubmission may be left alive.

* If none of the previous submissions get many comments / points, the resubmission may be left alive.

* If there is an intentional systematic resubmission, the moderators may hellban the user and put the domain in the autokill list and other nasty things.

... and if your attempts at self-promotion using Show HN fail miserably, is it acceptable to the community if you try again using a different headline? If so, how long in between, weeks? Months?

A better idea is to write a technical blog post about a unique feature of your site. (Bonus poits for nice graphics or photographs.)

For example read: http://blog.wolfram.com/ All the blog can be resumed as "You can do a lot of calculations and nice graphics with Mathematica" But many of the individual post have interesting information (and nice graphics) and got a lot of points https://hn.algolia.com/?q=wolfram.com#!/story/forever/0/blog...

Submissions to HN are allowed based on unique URLs.

Each of the submissions to that wiki article have slightly different link structures. For example, one has a trailing "/" and one does not.

You can do it by adding "/#" anchor link at the end of the link over and over.

Link.com/mysubmission

Link.com/mysubmission/#

Link.com/mysubmission/##

Link.com/mysubmission/###

Link.com/mysubmission/####

I'm not sure if it pisses people off but that's the technique I've used before. Resubmit at different times of day. It's tough to get your submission exposure because different crowds are on at different times of day. So really good articles can be ignored simply because they were submitted at the wrong time or wrong day and no one was there to upvote it. That's what I've always hated about Digg/Reddit/HN. You have to submit stories at some magical time.

My understanding is that submissions that are not accessed for some time drop out of the cache and then can be re-submitted. I can't find the comment from PG or dang though.