This is going a bit too far:

enter image description here

Can we start with just the most interesting questions that people are really struggling with? That's what SE is for, isn't it? When I started using SO almost 10 years ago, it was a place to go when I really needed help with something.

There is also another issue I have with this series. Very soon SLesslyTall will have a higher reputation than absolutely anybody here, and will have access to moderator tools, will be able to decide what questions stay open or get closed, etc. The reason people with high reputation get high power is because they have earned it by showing that they have the capacity to ask very good questions or give very good answers. In every SE I know, asking lots of excellent questions involved having creativity or having original ideas.

When copying and pasting questions from N&C, it is actually Michael Nielsen and Isaac Chuang that made the intellectual creative effort. They were the ones creative enough to come up with good questions. If you've ever written a textbook, you will know how excruciatingly difficult it is to come up with good, creative exercises. If you've ever taught a course, you know how hard it is to come up with good educational but do-able homework exercises.

Michael Nielsen and Isaac Chuang were the ones that spent the time making these questions.

Every question I asked here was an original idea and written by myself. If you want, I can ask Ike Chuang tomorrow if he and Mike would like to set up an account where he can get reputation for people like SLesslyTall ask all the questions from his book. But otherwise, I do not think you should get free points accredited to your username for asking questions that other people came up with.

Finally, it is going to be extremely rare to hear me say this, but I don't think this particular question (Exercise 2.5) belongs here. I usually advocate including every question. It takes effort to ask a question, never delete it except in exceptional circumstances. I have read the meta post about "assuming that a question is about quantum computing" and giving the "benefit of the doubt". But this question is just a very basic math question that belongs on the Mathematics SE (in the event that someone actually struggles to get the answer themselves, which I think is impossible so it might even be considered off topic there, for not making any effort to do one's "own research" before asking the question).

I still think more than half the points for the question should go to an account in Mike or Ike's name, since they came up with the "interesting question". It doesn't take much effort, creativity, or original work to copy a question out of a book. Points for effort that goes into typing a question in LaTeX format? I don't think so... I envision that it's going to be like someone reading N&C and getting stumbled by how hard a question is, and then asking for the answer here. Why should they ever get points for that?


4 Answers 4


I have a few concerns with this approach to generating content which I will outline here for your consideration:

The first is largely an ethical stance

By copying the problem statements from someone else's body of work, I believe it diminishes the value of what that author has created. A lot of work goes into the creation of these works by your colleagues — so while the Fair Use provisions of most Copyright law allows for using small snippets of content for the purpose of education, when you set out to reproduce those exercises en masse, I believe you cross over a line into what I feel is misappropriating the original author's hard work without permission.

Incidentally, one "take down notice" and all that content will be removed unceremoniously; it will just be gone. But I don't think this community needs to dance on that edge of that quasi-legal jargon to see if the author will protect their work. We don't need to do that. There are plenty of "real world" problems to solve here.

Which leads me to my second concern:

Recognizing why this site was created

This site is built through a collaborative effort by sharing actual detailed problems you encounter in your day to day work or studies in the form of Q&A. Others share their hard-earned experience to resolve these hurdles one by one so these issues become well-documented for those who might encounter the same problems thereafter.

But this site wasn't meant to become a digital "problem solver". Many sites run into a problem (often referred to as a "homework problem") where folks hand off a bit of work with the question "can you do this for me?"

I understand that the N&C examples were meant to be more of an exercise for your practice and intrigue — I wouldn't assume any bad faith — but the way these questions should be asked is in the context of working on these problems or projects yourself. Then… if you run into a very specific concern or point of confusion, you can ask how you might overcome that hurdle together.

  • $\begingroup$ I could not agree more. This answer could not be any more perfect, so I have accepted your answer. I didn't want to completely discourage the user that was posting these questions, because I do see some value in asking some of the most interesting and non-trivial questions of N&C, but your suggested approach is actually better. The users should ask about the specific problem they have that is making it hard for them to solve the problem, rather than just copying and pasting the whole question. [cot'd] $\endgroup$ Commented Jun 29, 2018 at 17:27
  • $\begingroup$ They can write down that it's related to N&C Exercise 2.5, so people who come to SE for help on the question know where to find it, but they don't need to copy and paste the entire question. $\endgroup$ Commented Jun 29, 2018 at 17:28

I feel the need to make a brief set of points that seem to have been lost in the past week's melee:

a) I am a (relatively) new SE user. I have not had a decade of previous experience on what is and isn't allowed on the site, for which I can only offer my humble apologies.

b) In an attempt to overcome these fatal shortcomings, when I had a question about what might be allowed on the site, I openly and honestly requested for advice on how to proceed. Specifically, I questioned the means and appropriateness of listing (specifically) all the N&C questions, from which the general consensus seemed to be: "yes, this is a good idea". I further note that this was motivated entirely by an altruistic wish to provide future students with a resource that I had personally desired years ago, not some rep-gaining conspiracy to take over the site. In fact, personally, I have very little to gain from spending my time writing and answering these questions.

c) In response to this, I did exactly what was suggested, including additional later requests, such as the maintenance of the tag page.

d) At no point in this sequence of events have I attempted to deceive anyone on either my intentions or actions. If this is not something that the community wants on the site then that absolutely is fine with me. I also certainly did not have any intent to infringe any copyright laws and meant absolutely no disrespect to Mike nor Ike, for whom I am very much grateful.

However, what I do resent is being made to feel (and let me be explicit here: by the tone of this post and that of your subsequent responses) that what I have done here is somehow subversive, rogue or morally corrupt, especially given how much I clearly attempted to act in genuine and good faith.

Ultimately, if you and other mods want to the site to expand, grow and become more than it is now, then ultimately there has to be space for users to attempt improvements to the site, and yes, sometimes even have those attempts fail, without feeling like they have ruined the site in doing so. In real life, those of us who aren't perfectly logical Ubermenschen often learn just as much from a bad question or incorrect answer. So, if you want new users to feel they have the space to innovate and explore new possibilities for the site, then I would honestly suggest that you take more care to deal with these cases with a light and pastoral hand, rather than with a master's cane.


tl;dr- I'd guess that contacting the authors and asking them for guidance would be the way to go. Given that:

  1. we'd basically be advertising their work and providing free tech support for it;

  2. the primary author announced that they're switching fields from quantum computing research to "development of new tools for scientific collaboration and publication";

it seems entirely plausible that they'd give their blessing or/and join the community!

There seem to be three concerns:

  1. Does the SE community benefit from having content like these questions?

  2. Is it appropriate that a user should receive reputation, and thus moderation privileges, for posting these questions?

  3. Is it appropriate to reproduce the authors' work?

Listed these from weakest to strongest so I can address the weaker concerns quickly, then discuss the larger issues. Then an additional point:

  1. Should we invite the authors to SE.QuantumComputing?

1: Does the SE community benefit from having content like these questions?

This seems like a clear yes. Having solutions to commonly worked textbook problems seems beneficial to both those trying to work them and to readers who just want to read over the solutions.

This is, I don't think it's reasonable to even be concerned that these questions are themselves detrimental to the community for lack of merit as content.

2: Is it appropriate that a user should receive reputation, and thus moderation privileges, for posting these questions?

In a general context, this would seem like a complicated discussion topic on the nature of merit and how users should be trusted with moderation power given their prior interactions with the community.

However, StackExchange's reputation and privileges model is beyond broken. It's basically just a quasi-randomized speed-bump before users get moderation abilities; my impression's been that it's more about entertainment and getting users invested than anything else.

For example, someone posted "What's the difference between git pull and git fetch?", the body of which is just the title copy/pasted, and that's gotten ~50k rep so far, which alone would grant them all rep-based privileges with plenty left over for awarding bounties.

In general, mass-appeal questions and answers tend to get the upvotes. If it's a common topic and users already agree with what's being said, they'll often just rubber-stamp something with their up-vote. There've been proposals to try to offset this tenancy, e.g.

Something I notice is when there's an advanced/specialized question, it often receives very few upvotes. Even if it is seemingly well written. I try to upvote advanced questions that I might not even understand, if they appear well written.

Is this good behaviour? Should we encourage upvoting seemingly well-written questions even if you don't understand it?

"Should we encourage upvotes on more advanced questions, that are seemingly well written, even if you don't understand it?", SE.Math.Meta [formatting omitted]

, but realistically speaking it's a consequence of StackExchange's basic model; it would need to be addressed by the developers and it's unlikely something that the community can really do much about.

Anyway, the point's that rep from easy, mass-appeal content is basically the norm throughout much of StackExchange.

3: Is it appropriate to reproduce the authors' work?

This seems like the big issue to me.

So, for context, we're talking about

The first author has put the first 29-pages up on his website in this PDF. A new copy of the latest edition in hard-cover is going for $63.21\,\mathrm{USD}$ on Amazon.com right now.

Anyway, the main concerns here would seem to be:

  1. Are we harming the authors' interests?

  2. Are we violating copyright law or any other legal standard?

  3. Are we falling short of any reasonable ethical or moral standard?

For (1), I suspect that we'd be supporting the authors' work by essentially providing free tech support. From the book reviews I've skimmed, it sounds like there's not an existing solution manual and the book has a significant amount of errata, so I'd imagine that it'd be positive for the authors.

For (3), the main concern seems to be if we'd help facilitate piracy of protected intellectual content. I think that this can be dismissed largely on the basis that the first Google result for the book's title was a PDF of the latest edition. So if anyone does want to pirate it, I'd imagine they'd just download the PDF.

I'm not sure about (2). I mean any individual question reproduction sounds like fair use to me (not legal advice, etc.), but copying all of the questions would seem to reproduce a non-trivial piece of the book.

Anyway, given all of this, the simplest solution would seem to be contacting the authors and asking. When researching this, I noticed a bit more information, so continuing into Section 4...

4: Should we invite the authors to SE.QuantumComputing?

A lot of folks are really into the ideas of open science and spreading information through platforms like StackExchange. I mean, that's basically why I'm messing around here!

So, I went to check if the authors happen to be the same mindset, and found this:

Changing fields

After 12 years of work on quantum information and quantum computation, I’ve decided to shift my creative work to a completely new direction.


The new direction I’ll be working toward is the development of new tools for scientific collaboration and publication. This is a tremendously exciting area, and it’s also one where my skills and interests seem likely to be useful.

Michael Nielsen's blog (2007-09-28)

Given such a powerful statement of interest in basically what we're doing here from an author of one of the field's main textbooks... I mean, wow, if we haven't invited them yet, seems like it's time!

  • $\begingroup$ @Blue Yeah, though the authors would seem to be in a better place to engage the publisher as well as comment on whatever allowances the publisher may've already granted, assuming that they'd be for posting content from their book. $\endgroup$
    – Nat
    Commented Jun 30, 2018 at 5:47
  • $\begingroup$ These are all great points and I thank you for such a thoughtful and well-written post on this. I would add that if anything, surely the posting of these questions would act as an advertisement for the book to new QC students entering the field. I would be surprised if CUP did not see this side of it and therefore give their permission on that basis alone. The questions by themselves really aren't that useful to a student without the book to understand their context. $\endgroup$ Commented Jun 30, 2018 at 9:06

Heather asked me to write an answer based on her comments:

enter image description here

I lean in favor of this suggestion.
If the asker doesn't get reputation for the original work of Michael Nielsen and Isaac Chuang, then that makes things much better.

The question then would be which questions are appropriate and which ones are not. The question posted, is not interesting. It is not quantum computing, but high school math. There is a reason why extremely basic questions are not generally accepted on SO or other SE's. People shouldn't be able to reach 5000 points for answering a bunch of trivial questions. There's some questions in N&C that are genuinely difficult. There's other ones which are trivial and do not merit points for simply typing out the solutions to essentially a high school homework question.

SO and many of the SE's are a bit more advanced than that. Questions are non-trivial, and they are interesting. They are worth something.

  • $\begingroup$ I think the deciding factor for whether or not these questions are on-topic may simply be "is this about quantum computing"? i think the most recent question is an exception because it's just a linear algebra question, which probably belongs more on Math.SE. $\endgroup$
    – auden
    Commented Jun 28, 2018 at 23:00
  • $\begingroup$ So far, every single question in the series, has been a linear algebra question. Nothing to do with quantum. Someone already commented about that, and said that a discussion on Meta might be necessary. $\endgroup$ Commented Jun 29, 2018 at 4:42
  • 3
    $\begingroup$ And please do not use "community wiki" as a way to allow or forgive questions which otherwise would not work. A questions should be allowed (or not) based entirely on its merits. Community Wiki should not be used as a way to deprive or withhold reputation, and the Community Wiki feature has been all but deprecated as a tool in general. The option as been removed for an author to make their own question community wiki, and It is generally not recommended to use this tool for much at all — The Future of Community Wiki $\endgroup$ Commented Jun 29, 2018 at 17:18

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .