The Classical Channel

Anonymous

8:07 PM

@Mithrandir24601 Shiny new gold badge. Congrats ;)

Mithrandir24601

@Blue Thanks! The site's 100 days old apparently :)

Anonymous

@Nat too! Apparently only you both visited the site everyday :D

Anonymous

@Mithrandir24601 True :) Looking back, I think we've surpassed most expectations and done well :)

Mithrandir24601

@Blue Also Bytebuster and Vlad Spirin

Anonymous

At this rate, we should be graduating in an year or so

Anonymous

8:10 PM

quantumcomputing.stackexchange.com/help/badges/55/fanatic

Anonymous

Ah, nice!

Mithrandir24601

@Blue Yeah, I think we're doing reasonably well in terms of activity :) We had a very good week last week - something must have hit HNQ or something

Anonymous

The weighting matrix one surely hit HNQ :P

Anonymous

472 views

Mithrandir24601

@Blue I believe it was this one:

27

Q: Why is it harder to build quantum computers than classical computers?

Is it because we don't know exactly how to create quantum computers (and how they must work), or do we know how to create it in theory, but don't have the tools to actually execute it in practice? Is it a mix of the above two? Any other reasons?

"viewed 5,546 times"

Anonymous

8:13 PM

5,546 times

Anonymous

lol

Anonymous

awesome

Anonymous

Yeah, I remember

Mithrandir24601

Blimey, the scaling of votes on that one - 32, 10, 2, 0, 0, 0

Anonymous

Haha

Anonymous

8:19 PM

@user1271772 - The point of the Stack Exchange network is to be a repository of useful questions and answers - to be the Google result, not to send people to other places. — Mithrandir 4 hours ago

Anonymous

Regarding this: I should stress on the word "useful". Not all questions are useful and some are too broad to be useful.

Anonymous

When you write "easily understood by laypeople", just how "lay" are we talking? Can one assume they know about Huygen's principle? About complex numbers? About vector spaces? About momentum? About differential equations? About boolean logic? This seems to me a very vague constraint. I expect that there is a set of mathematical prerequisites, without which any description of 'a qubit' would amount to some vaguely technical sounding words which fail to actually convey anything in a convincing way. — Niel de Beaudrap 3 hours ago

Anonymous

Niel has a very valid point here

user1271772

@Blue: Why are you laughing at me for being told off by Mithrandir?

Anonymous

@user1271772 What?

Mithrandir

8:24 PM

How is Blue laughing at you, and how is that telling you off?

Mithrandir24601

@user1271772 I believe @Blue was laughing at this:

user1271772

"Haha"

Mithrandir24601

9 mins ago, by Mithrandir24601

Blimey, the scaling of votes on that one - 32, 10, 2, 0, 0, 0

Mithrandir

The "Haha" was in reference to the message above, not below, I believe.

Anonymous

Yes ^

user1271772

8:25 PM

Why am I tagged in that?

ACuriousMind

There's 3 minutes between the "haha" being posted and the comment.

Mithrandir

Also... assume good faith.

Semiclassical

I'll say, though, that the timing of the messages isn't obvious unless you look at the transcript

user1271772

How do we see the transcript?

Mithrandir

chat.stackexchange.com/transcript/74398

Semiclassical

8:26 PM

click the "room" dropdown below the room description

ACuriousMind

@user1271772 If you click on the arrow at the left of a chat message, the time when it was posted is in the menu that drops down.

user1271772

@Mithrandir: Usually I would "assume good faith" but as you've seen I've been upset at some behavior of Blue towards me in the past including today

Mithrandir24601

@Blue Anyway, I was going to say that Mith's comment is also dead on and it's up to the community to decide whether or not this is on topic - I feel this is a really good question from the point of view of 'what is the scope of this site?' - if it is too broad, is it too broad because of what Niel said (which is certainly a valid point) or is it too broad because asking "what is a qubit?" would just require too long an answer to explain at any (useful) level of detail or something else?

Anonymous

@Mithrandir24601 I'd say - both

user1271772

@Mithrandir: Thanks for the link but I clicked on it and can't find where the time is listed, it only shows the time for SOME messages. I guess ACuriousMind's method is the way to find out what time messages are sent

Anonymous

8:36 PM

@Mithrandir I had asked a similar type of question before: quantumcomputing.stackexchange.com/questions/2030/… (not about qubits, but anyons)

Anonymous

(dissecting the Wikipedia page and pointing out the exact places where I was stuck)

Anonymous

I don't think it's perfect, however, I feel it is a good model for how such questions should be asked

Anonymous

If you can do that for your question, I think you'll get a much better response

Anonymous

(if you're genuinely interested in the subject i.e.)

Mithrandir24601

@Blue On the other hand, that doesn't mean that an answer here couldn't be better in some way than a Wiki article, doesn't mean that we wouldn't rather have the traffic to SE and doesn't mean it's a bad question

Anonymous

8:39 PM

Tell us exactly how much math and physics you know in the question! That's a very important skill

heather

@ACuriousMind greetings =)

Anonymous

@Mithrandir24601 Let me state my points: 1) I feel being able to dissect technical material into portions you can't understand is a very important skill. I do not believe in spoon-feeding people 2) Being able to convey how much you know and exactly how much you do not know, is an important skill too 3) Personally participating SE has improved my ability to convey and comprehend information with much more clarity, than ever before

Anonymous

Point 3 was only possible because I was forced to dissect difficult material on my own due to the strict standards SE held, earlier. The standards have fallen a lot these days though.

Anonymous

I don't want this to be a site for laymen. However, this can surely be a site for enthusiastic beginners, who are willing to work hard to understand the material.

Mithrandir24601

@Blue This is all very true and you're making good arguments for why the question should be changed in specific ways for the benefit of the OP. However, none of that explains why it's too broad :P

@Blue What a layman is and what a beginner is, is relative to the person saying those words

Anonymous

8:46 PM

@Mithrandir24601 "layman" = "casual reader" in my words

Anonymous

Someone who thinks they'll understand science by glancing through magazines written in plain English

Anonymous

@Mithrandir24601 I think Niel has covered the "broad" part well enough

Anonymous

9:04 PM

@Mithrandir: the shortest convincing description of 'a qubit' that I could give to a somewhat mathematically engaged but otherwise typical 15 year old would involve at least a one hour tutorial in physics about the double-slit experiment, the Stern-Gerlach experiment, and/or the Mach-Zehnder experiment. I'd be tempted to introduce vectors at the very least to talk about coordinates on the Bloch sphere. Precisely how I'd go about it would require careful thought and planning, and laying down some physics education to explain what 'quantumness' even consists of. It's no small task IMO. — Niel de Beaudrap 2 mins ago

Mithrandir24601

@Blue I do kind of feel a problem in your argument - I've had a couple of questions before that I almost asked here, only I did the thing where I looked up the answer elsewhere. I eventually managed to find the answer (in one case, it was actually in an arXiv preprint by Niel) but I would have gotten it easier and probably learned more in (and in less time) by just asking here

@Blue This is the other thing - if Niel de Beaudrap went to that much effort (I'm not asking him to or anything), I'd probably also find something useful/interesting that I hadn't really thought of before. Learning's not quite linear - covering the basics from the perspective of someone else (which often may not be covered in the likes of Wiki) can be a very illuminating experience sometimes

Anonymous

@Mithrandir24601 That may be true, however, I'm assuming that you at least knew what exactly you were looking for and that was focused enough to be answered in an SE post

Mithrandir

@Mithrandir24601 cough self-answer cough

Mithrandir24601

@Mithrandir I probably should just write the question and see what happens

Anonymous

@Mithrandir24601 I doubt anyone has the time or patience to cover that many things from the basics in a single answer

Mithrandir24601

9:10 PM

@Blue It's unlikely, sure, but does that make the question too broad?

Anonymous

You'd probably even get to learn those those if you asked that question in small fragments

Anonymous

In fact, I'd claim you'd (I'm talking about users in general, not you in particular) learn even more that way

Mithrandir24601

@Blue Also, I spent two weeks solid last December answering a single question on Worldbuilding. You'd be surprised at what can be interesting

@Blue Yes, this is true - smaller chunks tend to be better

Anonymous

@Mithrandir24601 For example breaking up the HHL question today into small parts helped me to grasp the details of each step (although I haven't finished asking all the confusions, yet)

Anonymous

I don't think just asking "How does HHL work?" would help me to understand the intricacies

Anonymous

9:16 PM

As a rule of thumb: If you spend equivalent effort in writing a question as compared to the person writing an answer for you, in general, you tend to learn much more. If you have spent only 5 mins in writing out whatever unrefined question popped up in your mind, you're less likely to try to understand a comprehensive answer written for you.

Mithrandir24601

@Blue It wouldn't, but it would mean that you wouldn't have had to go searching for all the right papers, hope that they're good papers, so that you don't waste more time, then learn all the papers in considerable detail, following all the slow loops and difficulties that come up in research and instead could have quickly gained a fair understanding and found out which papers are best to start from and learned the details from there

Now, you could argue that the first question you should ask should really be a resource-request...

Anonymous

@Mithrandir24601 For that, I'd first ask: "Which are the best introductory papers to understand the HHL?" (those are perfectly on-topic here)

Anonymous

Then I'd read through the top recommendations

Anonymous

And then ask my confusions after reading them

Mithrandir

I really don't think resource requests are a good fit for the SE model

Mithrandir24601

9:21 PM

@Blue This is very valid, sure. Still not always the most efficient though. It's the difference between going to a series of talks by someone and reading through papers that that someone recommended (although this is much better than trying to find them yourself). That someone will have already put all the effort into figuring out the optimal way through this, as they'll have already done it, so they can teach you the same stuff (if not more) in less time

glS

@Blue you know, I don't think I agree that much. Even a question like that could be quite useful. It wouldn't clear up all of the confusions of course, but an answer could provide an useful break-up of the major points to understand, together possibly with some references. The kinks could then be worked out through separate questions. I'm thinking something like the generic question serving as a sort of "table of content" for the more detailed ones

maybe it's just me, but I kind of have this dream that eventually SE sites + wikipedia could effectively serve as a better alternative to regular textbooks

Anonymous

@Mithrandir24601 That's an ideal situation where we're assuming someone who knows the algorithm very well already exists on the site and also that they can convey that information usefully in a single answer

Mithrandir24601

@glS We could also have a 'series of ...' idea, where someone asks some fairly large number of questions that follow directly on from each other, with a single meta post that lists the questions with a brief explanation or something (I may have nabbed this idea from Worldbuilding)

@glS I like that idea. It very much feels like a grand goal to really aim for

Anonymous

@glS But neither Wikipedia or textbooks would ever contain cutting edge-research matter

Anonymous

I was speaking more from the self-development perspective...that is, as a researcher it's a good skill to have - being able to comprehend unknown things independently as far as possible

Mithrandir24601

9:25 PM

@Blue Yes, of course

@Blue SE could, if done particularly well

Anonymous

@Mithrandir24601 I sort of understand your point of view, too

Quantum Computing

0

Q: What kind of real world problems (excluding cryptography) can be solved efficiently by a quantum algorithm?

This question is very similar as Is there any general statement about what kinds of problems can be solved more efficiently using a quantum computer? But the answers provided to that questions mainly looked at it from theoretical / mathematical point of view. For this question I am more interes...

quantum-computer quantum-algorithms

glS

@Blue yes of course, I'm talking of the basics (and not-so-basics). Though also research-level things can definitely be discussed on SE (and they are to some degree)

but for example, it would be really great if researchers could self-answer questions about their own papers, explaining things that don't fit well in "more academic" formats (though there would be some problems to work out for that to work properly).

Anonymous

@glS That's true

Mithrandir

@glS Especially on MathOverflow

Anonymous

9:37 PM

@Mithrandir24601 On a completely personal level, I think SE changed me from a kid who'd say: "I understand nothing of this and everything looks Greek to me" to someone who says: "I do not understand sentence 3 on page 4. I have looked up references x and z, however, they miss the point z...". That has helped me immensely in my own study life too. I would like SE to be the same transforming experience for all those who will manage to stick around.

Mithrandir24601

@Blue To be honest, I'm more like 'so much to do and not enough time!'

heather

11:45 PM

@Mithrandir I wrote an answer to your question; feel free to ping me with anything else I've skipped over or you want to me to add notes about.

i'll hopefully be updating it more.

glS

@heather nice answer. A few nitpicks: "* I could encode the whole works of Shakespeare into this one coin this way.*" this could be misinterpreted. Maybe a comment about the fact that while you could in principle cram as much information as you want, you cannot do it in a useful way (that is, you cannot do it in a way that can be decoded)

I wrote an answer on physics.SE about this some time ago, see here

heather

@glS good point, i'll clarify - that's why immediately after i talked about measurement, but you're right, i don't think it's clear enough.

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