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5:57 PM
Welcome to chat for: Quantum Computing
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1 hour later…
7:08 PM
Hi everybody!
Hi @Everyone :)
When did this chat get activated?
7:09 PM
Just noticed now
17:57 UTC by the looks of it
I see. Awesome :)
@Pavel Possibly edit in a link to the room? For some reason I can't
Is anyone here a professional QC person, or a grad student in this field? (Other than Mithrandir) It would be nice if everybody introduces themselves. :) I'm a first year engineering (ECE) undergrad
7:11 PM
@cairdcoinheringaahing There already is one
Oh yeah :/ The grey blends in to the background on my screen :/
@Blue This sums up all I know about QC:
in The Nineteenth Byte, 1 hour ago, by caird coinheringaahing
Annoyingly, I want to ask a question, but I don't have anything to ask, and joined the proposal mainly because I find it interesting, but not something I'd ask about :/
@Blue I am just an 8-th grader so no expert here :)
@cairdcoinheringaahing Cool :P
@Mr.Xcoder Yeah, we have spoken before, on hbar
7:13 PM
Oh yeah you changed your profile pic...
I liked Schrödinger :) But I like this one too
Room name we need...hmm...
I just came up with an awesome pun for the room name but I'm concerned it's not on-topic enough
what is it?
also welcome @Blue
Schrödinger's chat
7:17 PM
aboslutely +1 post that plz
A: What should we call our chat room?

PavelSchrödinger's Chat A pun on Schrödinger's Cat. It has more to do with Quantum Mechanics in general than just Quantum Computing, but I wanted to throw it out there.

@Blue mith is a gosh darned high school student he's not a professional or grad student
@Mr.Xcoder haha, and chat means cat in french
7:18 PM
+1 that's a great name
@Blue oh, you were the guy with the blue ring icon?
@Pavel It's good, but we already had the same name suggested a few times for the physics SE site's chat
Not very original
@Riker @Mithrandir24601 is a PhD student in QC
@Blue Aww
7:19 PM
My intro: I'm a quantum engineering PhD student and my PhD is to do with simulating open systems, PT-symmetric systems etc on a photonic chip, although I've got a variety of other interests relating to QC
wrong mithrandir lol
@Riker Blue ring? I don't remember. Probably not
I thought you were talking about hte other one who's on many private betas
@Riker People always do that :P It's quite funny
but hey cool nice to meet you @Mithrandir24601
7:20 PM
@Riker Good to meet you too :) I plan on spending much time here :)
In case you guys didn't notice we also have Daniel Sank, who is a member of Google Quantum AI group, on this site
^ i noticed that
I hope this site will gather more experts as time goes on
@Blue We've actually got a few academic QC people around/committed to the proposal, although I don't see any in chat currently
As for me, I'm a first year undergrad who has been learning the basics of QC from various online sources and textbooks for my internship this summer. Hope to learn a lot from the members on this site. :)
7:23 PM
lol I hope so too
@Mithrandir24601 Yep. For example:
@GypsySpellweaver \o
@GypsySpellweaver o/ welcome
7:26 PM
@Blue He's very active on MathOverflow, he's definitely a mathematician
@Riker So, uh, you didn't introduce yourself yet? ;)
I see you're a mod
@cairdcoinheringaahing QC is part of CS, physics, maths and engineering though, so you can still be any of those while being a 'QC person'
@Blue random high school kid from CA, USA who likes math
that's about it
@Mithrandir24601 Yeah, I was referring to Blue's (now deleted) message
7:29 PM
happen to be vegetarian/mod on
@Riker Oh, awesome. Lots of young blood in here :D
@cairdcoinheringaahing Aaahhh, fair. Fair :P
To be completely honest, quantum physics breaks my brain, so I expect I'll end up being a user with 101 rep in 6 years time, when this site really takes off :P
accepted edits give you +2 rep :)
There are a lot of rumors regarding quantum physics, but I really think if you are learning from the right material it's much simpler than what you would expect.
7:32 PM
I hope to gain rep from .NET knowledge when people ask about Q# rather than actual quantum computing knowledge
@Pavel Lol
remember y'all, upvote all the good things
helps people get ot things like 350 rep to review things
The Q# tag already got created
me and jknappen are pretty close atm
Someone has to burnicate it
7:33 PM
should be auto-done when somebody removes it
@Riker Right
@Riker resembles Dennis and Martin back in the day imo... You just need a couple of more trailing zeroes :P
I will post a few questions and answers on the main site when I get time this week.
Hi @VladSpirin
7:36 PM
@Mr.Xcoder I 'member when dennis celebrated legendary
@VladSpirin o/
@Riker Link please!
About what here write?
general discussion
7:39 PM
@Mr.Xcoder and then there was this comment
since kritixi coulnd't get a name right
Legendary, thanks!
y'all I ain't seeing any of them updoots
ya better get on it
9 mins ago, by Riker
remember y'all, upvote all the good things
9 mins ago, by Riker
helps people get ot things like 350 rep to review things
7:44 PM
Why does the users page only show the top 5?
It's showing all users on my end
Actually I think the 5 on a line meta bug is actually all on a line....
Is this on-topic?
It could be made on-topic if some more material is added
The OP shows no effort at all
Q: Cooling superconducting qubits

heatherIs a dilution refrigerator the only way to cool superconducting qubits down to 10 millikelvin? If not, what other methods are there, and why is dilution refrigeration the primary method?

7:54 PM
Good to see technical questions coming up
Hmm, should we set up a feed to post new questions in chat?
Only room owners and moderators can do that. I think it can be done, since the question rate is low as of now.
@Riker is a mod
I can do that
No harm in trying. If the question rate blows up we can think of stopping it.
7:58 PM
As of now it is 1 about question per 30 minutes
Or we can simply set up quick feeds?
I can set one up
Like The H Bar has
@Mr.Xcoder Right. Better idea
7:58 PM
@Mr.Xcoder Quick feeds?
But well the quick feeds don't show the question details
you mean a ticker?
Instead of being sent as messages a popup shows in the top left corner
no no no no no.
@Riker Hmm?
7:59 PM
in The Reading Room, Jan 18 '17 at 22:23, by Rand al'Thor
@BESW Oh, please not the ticker :-(
Yeah, a ticker. Not enough questions are being posted to merit that
Fair enough
please no ticker :(
it's annoying af, broken on zooms, and you nede to clear it
8:00 PM
@Mr.Xcoder Hi!
else firefox beeps at me
@Riker Yes, I guess everybody has agreed to that. :)
ok cool
Heather, I feel this might become a list question. Perhaps you could narrow it down? At this time, there probably is a small number of methods (maybe just one), but in the future there might be more, which would mean that more answers would be added... — ItamarG3 2 mins ago
8:01 PM
That's something
We need to figure out how to deal with list questions. Though in this particular case I'm pretty sure the list wouldn't be too long, and would fit in a single one paragraph answer.
Hi @heather
why does my question have so many upvotes
it's not great, go upvote good questions y'all
@Blue yeah, do you think my question is a list question? I'm not sure it is
And answers.
8:04 PM
@heather Well, in your case the list wouldn't be big i.e. :P
2 mins ago, by Blue
We need to figure out how to deal with list questions. Though in this particular case I'm pretty sure the list wouldn't be too long, and would fit in a single one paragraph answer.
yeah, ItamarG3 was saying in the future though it might be a problem...
@heather Right, that's my point
we have a meta, go post answers/vote :p
I think it should be on-topic.
8:06 PM
list-type question $\neq$ resource-recommendation type
tha'ts not what the meta is about
In this field, resources are constantly updating
it's about requests, not recommendations
answers that pertain to a specific resource will quickly become outdated.
Unless we come up with a strict evaluation process for list questions
There's this eternal thing:
Jeff Atwood on November 23, 2010

Over the last 2.5 years, we’ve identified a few problematic classes of questions that tend to get asked on our sites. Many of these are documented in our standard set of close reasons: exact duplicate, off-topic, subjective and argumentative, not a real question, and too localized.

However, as we launched the great Super User experiment, a new, previously unknown class of problematic questions emerged — the shopping recommendation.

That is, on Super User we began encountering questions like: …

Which offers good grounds
I read your answer @Riker I don't completely agree with your point of view
8:08 PM
then write a competing answer :D
We could convert all such questions to community-wiki type
And the answers too
i agree with Blue, but yeah, that q/a is not the same as that with list questions.
I dislike that options.
Unless it's a megathread\canonical
8:09 PM
Some list questions can add a lot of value to the site
Disallowing all of them wouldn't be very wise
Q: Quantum pairs for FTL communication?

ChristopherQuantum pairs (if that is the right name) is 2 atoms that are paired together and when you stop one from spinning the other also stops with the same spin. Can you use these pairs to have FTL communication between 2 computers?

Q: Can a quantum computer simulate a normal computer?

GlorfindelSimilar to the question Could a Turing Machine simulate a quantum computer?: given a 'classical' algorithm, is it always possible to formulate an equivalent algorithm which can be performed on a quantum computer? If yes, is there some kind of procedure we can follow for this? The resulting algori...

Q: What are the main differences between normal and quantum computers?

user77954The title pretty much sums it up – How are quantum computers different from normal ones? i.e. Do all quantum computers need to be supercooled, whereas normal computers just need fans? and similar. I am aware that these things are documented on other sites too (e.g. Wikipedia), but I think these ...

Q: What level of "confidence" of the result from a Quantum Computer is possible?

Rory AlsopAt a very basic level, reading or measuring a qubit forces it to be in one state or the other, so operation of a QC to gain a result collapses the state into one of many possibilities. But as the state of each qubit is probabilistic, surely this means the result can actually be any of those poss...

Q: Cooling superconducting qubits

heatherIs a dilution refrigerator the only way to cool superconducting qubits down to 10 millikelvin? If not, what other methods are there, and why is dilution refrigeration the primary method?

Oh my goodness
feeds are not a good idea atm
8:10 PM
Stop this feed
kill it
That was so sudden
@Riker thanks :D
Riker has stopped a feed from being posted into this room
@ItamarG3 ideally it wouldn't post like that anymore
its' just catching up
8:11 PM
There's a 15 min time delay approx
Solution: ticker
i will not condone such heresy
and/or add it
Ok why are they so bad?
@Riker I know. Which is why I asked it be removed.
They work pretty well on other SE sites
8:13 PM
Hi! I changed my mind. I've decided to stick around on this website a little bit more...
in about a week (hopefully later) we can add it again. When the explosion stream of questions begins.
@nbro Glad to hear it, hope you find something good to post!
@nbro Welcome
@ItamarG3 I think there will actually be less questions posted.
after a week?
8:14 PM
When we enter public beta
because that's the plan
that way it won't overwhelm.
Right, I'm expecting that the question rate will fall soon
This is the initial frenzy
People are posting like mad now, so that we have a base of questions when the public arrives
8:15 PM
See conlangs for example. Their activity declined instead of increasing
That decline is the point. It's not exactly good, but we can only have feeds if we don't have 5 questions an hour.
or 5 in 30 mins.
Imagine a feed from 10% StackOverflow.
Wouldn't this question
Q: Could a Turing Machine simulate a quantum computer?

Rikerby Turing Machine, I mean this as a theoretical concept, not as a physical machine, in case it's not clear. I know that a TM can theoretically simulate anything, but I don't know whether it could simulate something as fundamentally different as a quantum-based computer. Are there any attempts t...

be more appropriately asked on the theoretical computer science website?
@nbro What's that site?
Anyway, it's definitely specificially about QC, so even if it would also be on topic there it works here.
8:18 PM
(Showing off my knowledge of chat 💪)
(Just kidding :D)
I think we should start defining which type of questions should be asked here...
When this site is launched for public, will it be in beta stage or a mature site?
Supposed to be
@nbro We're already trying to do that on Meta
But due to the sponsorship, I have no Idea
8:19 PM
@ItamarG3 I don't see the Beta label
Exactly. The sponsorship changes things
Ask on Meta
That's what it's there for after all
I have a few issues with "resource-recommendation" and "list-type", which I will elaborate on, tomorrow
I absolutely don't agree with blocking them completely
Rather deal with them on a case-by-case basis
8:21 PM
Q: Math notation - Can we please have it enabled?

ItamarG3Thrilled to see this site start. Could we please have math notation (mathjax) enabled? Quantum gates, states and many other things are represented by matrices and vectors. So We'll need it.

I don't want to ask this question because I don't want now to do a little bit more of research. Anyway, it would be nice to have a question regarding the details of the newly announced quantum machine by Google: Bristlecone.
10^8 qubits? unlikely. I sniff something weird. Looking into it
ಠ_ಠ Ataco's userscript got a little in the way there
A few possibly interesting questions may be:
1. How does one evaluate the performance of a quantum computer?
Or, if you prefer to restrict yourselves, you may ask
2. How does Google evaluate the performance of their quantum machines (in particular, Bristlecone)?
Instead of Google, you may choose IBM or D-Wave, maybe separate questions?
3. What do we mean by "performance" of a quantum computer?
8:36 PM
Regarding my most recent meta... Am I too pedantic?
I can't reproduce on my phone
4. How does memory come into play in quantum computers? Is there an equivalent of RAM for QCs?
Are you using Safari?
@Mr.Xcoder It's fine. I'm dying to see more technical questions and answers come up. Mostly I'm seeing pop-sci type stuff as of now.
Same :)
8:38 PM
I'm waiting to see what question will be the first HNQ question :P
@nbro Sure there is. Isn't that literally what Qubits are? Memory?
@Pavel Qubits can be used as memory (if they've got a good coherence time/low loss), but that doesn't mean that all qubits are used as part of memory
I will come up with other questions. Anyway, we, as a community, should discuss possible (canonical) questions here and agree if they are good or not, then ask them! No?
So currently, all Qubits we've made are essentially Level 1 cache
How does <Q|C> chat look, as a room name?
8:45 PM
@Pavel I wouldn't go as far as saying all - there have been a good number of 'memory qubits' created - but the majority, certainly
Too hard to type out IMO
maybe Q |0>+C|1>
8:46 PM
@Pavel Just 3 symbols found on any keyboard :P
I don't get it. What's the reference?
@ItamarG3 That's a bit cryptic, but okay
@cairdcoinheringaahing It's a way to represent qbit states
@cairdcoinheringaahing Q = Quantum C=Computing |Q> is a bra vector notation. <C| is a ket vector notation.
8:48 PM
And yeah, that ^
I've been trying to think of a pun on Hadamard for a while now but I'm just not that good at this sort of thing.
I'm sorry about that XD
It has to be a good pun/reference
It also doesn't have to be obviously chat related
are you laughtose intolerant? was that too cheesy?
8:51 PM
Movies.SE has "The Screening Room" for instance
maybe "The Gate"?
or "The QGate"?
I always like chat naming
Can we close this question: It's simply too broad!
<Q|C> gate
:( There isn't a Unicode character for "qubit"
I don't like these room names with <>
8:55 PM
@nbro It was opened by some moderator
It had been closed earlier
it wasn't opened by a mod
@ItamarG3 ?
I think it was just normally reopened
8:56 PM
Yeah, I VTRO
Ah, okay
I had so many questions yesterday, but I can't think of a single one
5. How does the concept of "measurement" come into play when building a QC? 5.1. What exactly are we measuring in a quantum computer?, 5.2. How is "measurement" a problem or impediment to building QCs?
These questions may seem basic to someone who's already familiar with QCs, but their answers may serve as canonical answers to the whole community.
But all of those are answered by looking at the wikipedia.
I see 2 alternatives
8:58 PM
I like the idea of some canonical questions and answers like that. It's sometimes difficult for beginners to find the right info from Wikipedia
Either we go ruthless, like Mathematica. Anything already the docs is off topic.
@ItamarG3 Even if that's the case, the format of this website is another, i.e. a Q&A website.
Or we become forgiving, and just point to our own version of docs.
@Blue fair point. Consider my convinced.
Something like JR's canonical answers on Physics SE
Just come up with some questions you think people may have!
Discuss them here. If we all approve them, then we may ask them!!
9:00 PM
But before starting a canonical QA thread discuss here
I support making a reference question, CW, And it'll have all the answers to a list of basic questions.
proposition: sandbox
@ItamarG3 Agreed
@ItamarG3 In what sense?
similar to in meta faqs
We should just strive to create "good" questions and answers...
9:01 PM
@cairdcoinheringaahing a way to make sure that the canonical answers are actually good.
@nbro it doesn't contradict
Ah, so for the canonical answers, not for questions in general
Chat room name idea: The Unobservatory
Since you can't observe Qubits or they lose their state
Well, I'm off to watch stranger things.
Cya. I gotta go too
Anyway, I do not think it is a problem if this website grows slowly, provided that the quality of the Q&As are "excellent".
9:05 PM
(observe stranger things -> observe strange things -> observe strange quarks -> observe particles -> what now?)
@nbro What type of QC? A measurement based one, or a circuit-model one? Is the first issue that comes to mind...
@Mithrandir24601 Honestly, I am not qualified yet to answer your question...
Anyway, we may have a chat dedicated to proposals of questions. What do you think?
@nbro They're just 2 different types of architectures - 'measurement based' creates a large state of qubits that are measured bit by bit, with the outcome of each affecting the operations being performed on the others (using feed forward), while 'circuit model' is the one that most people know of, where you start with some initial state and apply unitaries before measuring at the end
@nbro Sounds like a good idea - we could also have a meta sandbox (i.e. a post on meta where people answer with proposed questions)
I disagree with that
@cairdcoinheringaahing OK. Depends what others think of course though :P I have seen it used very well on Worldbuilding SE
9:16 PM
A Q&A site doesn't need a proposed question sandbox, that's what editing is for
@Mithrandir24601 Sorry about the tone of that, it came off all wrong :/
@cairdcoinheringaahing I meant during this initial phase, given that we still don't know exactly which questions are on topic here.
@cairdcoinheringaahing Ah, but the point is that people can suggest much more freely without questions having to get closed/reopened left, right and centre
@cairdcoinheringaahing Nah, you're good :) You're perfectly welcome to disagree
@Mithrandir24601 Yeah, that's a good point!
We have a Sandbox on PPCG, due to the fact that making a good question on that site is way more difficult than on a normal site. I think seeing whether questions would actually need a Sandbox would be a nice course of action e.g. if we get a ton of poorly constructed, poorly worded questions, rather than the odd one, then it would make more sense
Otherwise, it seems too precautionary IMO
@cairdcoinheringaahing Fair. There are a few questions that need a bit of fixing, but I do agree it's early days
9:21 PM
And also there’s this cool feature called “editing” :P
5 mins ago, by caird coinheringaahing
A Q&A site doesn't need a proposed question sandbox, that's what editing is for
Ninaj'd :P
Yeah I don’t think Q&A sites would ever need sandboxing either
2 hours later…
10:53 PM
Are we the only site that has a main design but no chat design
Way too early to know if a sandbox is worth considering yet. If and when users have a consistenly hard time creating questions that are reasonable for the site then a sandbox seems worth discussing on Meta. (Just my twopence worth.)
Yeah. I doubt it'll come to that.
I don't thing it will either. The largest problem I see with this site's questions is the education of new users brought in through the sponsorship that have no SE experience, and lots of experience in various fora and mailing lists.
11:14 PM
Which isn't necessarily a bad thing. A brand new beta site needs all the help it can get.

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