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October 21

Unitary Transformation

Is there any unitary transformation that satisfies $T(|a0z\rangle +|b1z\rangle )=(|a\rangle -|b\rangle )|z'\rangle$ , assuming z' is one qubit longer than z ? (there's a minus sign, rather than a plus, in order to increase the probability of T to be injective, and thus, to exist) 31.154.92.193 (talk) 05:57, 21 October 2015 (UTC)[reply]

No, because when a=b, the rhs is zero. If you replace the − with +, and allow z' to depend on a and b, and don't require z' to be a computational basis vector, then I think CNOT satisfies the conditions:

T(|00\rangle +|01\rangle )=(|0\rangle +|0\rangle )(|0\rangle +|1\rangle )/2

T(|00\rangle +|11\rangle )=(|0\rangle +|1\rangle )|0\rangle

T(|10\rangle +|01\rangle )=(|1\rangle +|0\rangle )|1\rangle

T(|10\rangle +|11\rangle )=(|1\rangle +|1\rangle )(|0\rangle +|1\rangle )/2

-- BenRG (talk) 18:55, 21 October 2015 (UTC)[reply]

Wow, great! :) (I thought that maybe both that with + and that with - don't exist)

Thank you very much!! 132.67.105.183 (talk) 08:36, 22 October 2015 (UTC)[reply]

Setting up a local git repo

Bitbucket gives the following instructions for settings up a git repo:

   Set up your local directory

   Set up Git on your machine if you haven't already.

   mkdir /path/to/your/project
   cd /path/to/your/project
   git init
   git remote add origin https://user@bitbucket.org/bob/smith.git

Wouldn't "git clone https://user@bitbucket.org/bob/smith.git" accomplish the exact same thing? Is there any difference in the resultant setup between running those four commands and running a git clone?731Butai (talk) 06:04, 21 October 2015 (UTC)[reply]

It looks to me like those instructions are for creating a new remote git repo. As you say, git clone is easier if the repo already exists.--Phil Holmes (talk) 11:21, 21 October 2015 (UTC)[reply]

Lawrence wikipedia article destroyed and hacked

hey, I have heard that in 2014 there was uploaded nude pics to Lawrence her page and the wikipedia press office has mentioned, they couldn´t find out who was the hacker. Is this until today true? I can not find any other information that the hacker has become caught and I ask myself how someone can manipulate the wikipedia and not becoming caught..--Poker chip (talk) 15:40, 21 October 2015 (UTC)[reply]

There are over a dozen females listed at the page Lawrence (surname). Could you tell us which one you're referring to? Rojomoke (talk) 17:13, 21 October 2015 (UTC)[reply]

Probably this one, given the news event mentioned in that section. --174.88.134.156 (talk) 17:53, 21 October 2015 (UTC)[reply]

It wasn't a hack. Everyone "manipulates Wikipedia"; it's the encyclopedia that anyone can edit. Someone uploaded two of the leaked nude images of Jennifer Lawrence to Commons so that they appeared in her article. Someone else deleted them within a few minutes. The offending uploads, by users "Saabelms" and "Willaabed", are still visible in the log. -- BenRG (talk) 18:10, 21 October 2015 (UTC)[reply]

I have a question about getting a new computer

I currently have a windows computer and I would like to get a newer-used computer where I can use skype and not get so many viruses for openning so many tabs. Please help me. 209.53.181.75 (talk) 22:13, 21 October 2015 (UTC)[reply]

You might be interested in list of antivirus software such as the products of malwarebytes. You might also consider using Firefox with NoScript and/or AdBlock Plus. SemanticMantis (talk) 23:06, 21 October 2015 (UTC)[reply]

To expand a bit, the OP should realize that a new computer won't be any less vulnerable to viruses than an old computer. It's the software on the PC that controls whether viruses can be stopped or not. One option is to completely wipe your old PC and reinstall the operating system, but there are also many other options to clean out viruses besides that. StuRat (talk) 02:18, 22 October 2015 (UTC)[reply]

Unless its so old that it would really struggle to run a newish (i.e. still receiving security updates) version of Windows (and the OP doesn't wish to switch to another OS family). davidprior ^t/_c 20:17, 23 October 2015 (UTC)[reply]

Perhaps a refurbished iPad would meet your needs. Skype for iPad is available at no cost. Nimur (talk) 01:54, 22 October 2015 (UTC)[reply]

If skype is about as much as you need the "computer" for, I second the suggestion of trying an iPad. Skype on iPad is great, I use it all the time. Vespine (talk) 21:48, 22 October 2015 (UTC)[reply]

One could install a Virtual Machine and put (say) Ubuntu Linux on it. Then, one can add Skype on Ubutu and surf (with Firefox) and email. If the OP only wants to Skype, email, word-process, surf and other normal things, then just wipe off Windows and install (say) Ubuntu Linux. It is a lot easier to maintain, faster and doesn’t suffer from Windows viruses and malware. Total cost … Zero. It's free and more reliable. --Aspro (talk) 22:24, 22 October 2015 (UTC)[reply]

As Nimur, Vespine and Aspro say - if the only use of the computer is going to be Skype, then something other than a Windows computer may be the best solution (iPad, Android tablet, Linux computer, Chromebook, Smart TV or Games console with a skype camera, etc, etc.) davidprior ^t/_c 20:17, 23 October 2015 (UTC)[reply]

Even new machines may come with crapware, used computers may have caught malware. It is recommended to reinstall the machine. About security and privacy ever memory should be flushed and reprogrammed with its software from reliable source. Warning: If your have no experience with reflashing the UEFI/BIOS and installing the operating system, get this basic information first due making the system inoperable and have help form friends You trust and who know about. Opening many windows Your own is just a question of the required RAM size. As different formats are needed on different mainboards, check prices and possibility to upgrade or configure a system. Sometimes new memory with same size can be avail at lower costs. See compatibility lists and mainboard specification/manual. If Your computer opens various browser windows, renew anitvirus software from trusted source. There's an umbrella for free and a system without crap may speedup. --Hans Haase (有问题吗) 11:01, 24 October 2015 (UTC)[reply]

@Nimur, Hans Haase, Davidprior, StuRat, Aspro, and SemanticMantis:peerblock, all 14 inbuilt blocklist active, make huge range of IPs, malware transmitting-receiving ones block. stop auto-recieving of malware, botnetMahfuzur rahman shourov (talk) 14:09, 24 October 2015 (UTC)[reply]

These third party solutions like Peerblock are firefighting I.E. They just concentrate on short-term 'fixing' of problems, or suppression of their symptoms, rather than understanding and addressing the factors that cause the problem. One might as well bang one's head against a brick wall, in an effort to make a silk purse of a sow's ear out of an OS when there may be better operating systems and applications that provide one with what one needs and find useful. Instal a virtual machine, load up some other operating systems and try them out. If anything goes pair-shaped then no worries. On a VM one just winds back to an earlier version. You might find a step learning curve to begin with but as they say -no pain, no gain. Get your nearly-new- computer, wipe the existing OS and install Linux Mint. The user interface may look odd at first but windows is desperately trying to follow it despite Metro (which is term they are no longer allowed to use). Don't follow the followers but join the leaders. What is is important is not the razzmatazz but what the operating system does for you.--Aspro (talk) 17:15, 24 October 2015 (UTC)[reply]