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Groups > comp.programming > #5777
| From | Mok-Kong Shen <mok-kong.shen@t-online.de> |
|---|---|
| Newsgroups | comp.programming |
| Subject | Re: Researches in quantum computing seem to progress only extremely slowly |
| Date | 2015-09-03 03:54 +0200 |
| Organization | albasani.net |
| Message-ID | <ms8987$c4c$1@news.albasani.net> (permalink) |
| References | (17 earlier) <ms85il$ur$1@speranza.aioe.org> <ms85tu$68u$1@news.albasani.net> <ms86hp$2jl$1@speranza.aioe.org> <ms87su$ab0$1@news.albasani.net> <ms88ok$6hc$1@speranza.aioe.org> |
Am 03.09.2015 um 03:45 schrieb bartekltg:
> On 03.09.2015 03:31, Mok-Kong Shen wrote:
>> Am 03.09.2015 um 03:08 schrieb bartekltg:
>>> On 03.09.2015 02:57, Mok-Kong Shen wrote:
>>>> Am 03.09.2015 um 02:51 schrieb bartekltg:
>>>>> On 03.09.2015 02:22, Mok-Kong Shen wrote:
>>>>>> Am 03.09.2015 um 02:01 schrieb bartekltg:
>>>>>>> On 03.09.2015 01:28, Mok-Kong Shen wrote:
>>>>>>>> Am 03.09.2015 um 01:21 schrieb bartekltg:
>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> This is exactly the answer to you question about 'mean entropy'.
>>>>>>>>> You did not understand the direct answer because you do not
>>>>>>>>> know math about entropy. This is why I also wrote the second
>>>>>>>>> post about simplified problem, but with the same question
>>>>>>>>> and answer.
>>>>>>>>>
>>>>>>>>> If I have a candy in one hand I do not have a half of bits
>>>>>>>>> of enthropy in each hand. I have one bit in left and one
>>>>>>>>> bit in right. But both bits are corelated, so if you
>>>>>>>>> known one, you also known the second - second hand
>>>>>>>>> have zero entropy, because ("under the assuption the
>>>>>>>>> first hand in known") you known where the candy is.
>>>>>>>>>
>>>>>>>>> "Mean entropy" as you proposed ("128/n") have no sense,
>>>>>>>>> because probability doesn't work that way.
>>>>>>>>
>>>>>>>> Ok, then simply entropy. Lets say that the 128 input bits
>>>>>>>> are all of full entropy, each bit has entropy of 1.0. We
>>>>>>>> assume that AES is very well designed such that the output
>>>>>>>> n bits are equally good. How much entropy has under this
>>>>>>>> assumption one output bit?
>>>>>>>
>>>>>>> One bit.
>>>>>>> If AES is good, both 0 and 1 is equally probable,
>>>>>>> so entropy is
>>>>>>> -1/2*log(1/2) -1/2*log(1/2) = 1
>>>>>>>
>>>>>>>
>>>>>>> Entropy of two bits is almost two.
>>>>>>>
>>>>>>> Entropy of the whole n bits is not greater than 128bits
>>>>>>> //forth dot
>>>>>>> https://en.wikipedia.org/wiki/Entropy_(information_theory)#Further_properties
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>> So, assuming that the n bits are equally good, the entropy
>>>>>> of each output bit is not greater than 128/n. A trivial
>>>>>> calculation, isn't it?
>>>>>
>>>>> No. You still don't get this hands and a candy story ;]
>>>>>
>>>>>
>>>>> We have two bit random sequence.
>>>>> 00, 01, 10, 11, all with probability 1/4.
>>>>>
>>>>> AES_2_4 generate:
>>>>>
>>>>> AES(00) = 1011
>>>>> AES(01) = 1000
>>>>> AES(10) = 0111
>>>>> AES(11) = 0110
>>>>> [you can write better "AES" bunction and recalculate entropies]
>>>>>
>>>>> Do you know definition of entropy?
>>>>> x_i are possible sequewnces. P(x_i) propability od that seqence.
>>>>> entropy H = \sum_i P(x_i)*log2(1/P(x_i))
>>>>>
>>>>> Entropy of first bit is 1
>>>>> Entropy of second bit is 1
>>>>> entropy of third bit is 1/4log2(4) + 3/4log2(4/3) = 0.81128
>>>>> entropy of fourth bit is 1
>>>>>
>>>>> Entropy of first two bits?
>>>>> We have only two possible sequences. 01 and 10.
>>>>> Both have probability 1/2. So H = 1
>>>>> First two bits have only one bit of entropy.
>>>>> -How, first bit have one bit, and second bit have one bit,
>>>>> this is total two bits!
>>>>>
>>>>> look at the sequences. If I look at first bit and it is 1,
>>>>> i know random sequieince was eithier 00 or 01.
>>>>> But if I look at the second bit, I will not get any new information,
>>>>> i knew before tjat second bit is NOT first bit.
>>>>>
>>>>> First bit carry information, second bit carry information,
>>>>> but this is the same information.
>>>>>
>>>>> Second and third bit can be: 00, 01, 11. The last
>>>>> with propability 1/2, first two - 1/4. H = 1.3466
>>>>>
>>>>> The first and the last bit:
>>>>> sequences:
>>>>> 11 10 01 00. propability od any =1/4. H=2.
>>>>>
>>>>> If I look at these two bits, I can decipher whole sequence.
>>>>> They carry whole information. If I know that, the rest of
>>>>> the sequence have no more information for me.
>>>>>
>>>>> Entropy of whole sequence is... of course 2 bits,
>>>>> beceuse i have 4 possible sequences, echch with 1/4 chance.
>>>>
>>>> Sorry, please find possible logical faults in what I have
>>>> stated in my paradox, e.g. why my calculation is wrong.
>>>
>>>
>>> "128/n bits of entropy in one bit" is wrong.
>>> You do not give us mathematical proof of your claim,
>>> so I cant point at a specific logical fault other than this.
>>
>> But that's exactly simple math calculation, on the assumption
>> that AES output bits are equally good, i.e.
>
> Yes.
>
>> having equal entropy,
>
> Be carefully. Can you prove that?
> Yes, this is also true (for 1 bit sequnces, for k-sequences,
> where 128<k<n is obviously not true).
This is, as said, assumption. (For ease of discussion one could commonly
idealize a bit, or are you unfamiliar with that?)
> Not only all bits have equal entropy, but all bits have
> entropy equal to one bit.
Oh, then what is the total entropy of the n bits? You would then
have a wonderful machine of creating lots of entropy from 128 bits
input!!
Anyway, I repeat, please ALSO write an post answering Wessel,
similarly telling him that he is wrong in his calculation in your
opinion.
M. K. Shen
>
> From 'entropy of every bit is equal' you can't conclude
> that entropy is divided.
>
>
>
> About that was the "candy"post.
> I have one candy, keep it in one of two places.
> Every place hold 1 bit of information, not half.
>
> ******too much messages ago***
>
> I have one candy. I hide it in one of my hands and present
> both hand to you. Information, where is the candy is one bit.
> It is either in the left or in the right hand.
>
> Do you think that if I open one of my hands, you get
> a 1/2 bit of information? And when I open the second
> one - net 1/2 bit of information?
>
> No, the whole bit is in my left hand in the same way it is in
> my right hand. When I open the first hand you will get whole bit
> of information, and when I open the second hand, you gen no new
> information, 0 bits.
> ****************
>
>
>
>> isn't it? If you still don't want to accept this, then you should
>> at least, to be fair, also respond to the post of Wessel where he
>> agreed with my calculation and similarly tell him that he is wrong
>> and see what he will react to that!!
>
> I have posted an answer to his message, this post included a brief
> description between a small volume of milk and random variables.
>
> Also, think for yourself;>
>
> bartekltg
>
>
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Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-01 13:09 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-01 14:23 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-01 20:00 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-01 18:43 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-02 10:48 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-02 13:00 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-02 22:50 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-02 21:31 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-02 23:46 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-02 21:58 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 00:13 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-03 00:32 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 02:47 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 16:52 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 00:03 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 17:18 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 00:28 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 17:52 -0500
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 01:04 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 18:29 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 01:04 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 18:25 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 01:33 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 18:53 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 02:16 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 02:18 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 02:33 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 02:42 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 02:55 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 03:03 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 03:14 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 03:17 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 03:30 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 03:36 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 04:13 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 04:19 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 04:32 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 22:51 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 16:51 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-03 10:49 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-04 19:47 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-04 13:42 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-04 21:50 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-04 20:33 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-04 23:45 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-05 01:24 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-07 00:50 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-07 14:14 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-07 15:57 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-07 12:19 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-08 23:47 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-09 02:28 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-04 20:23 +0000
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-05 00:55 +0200
Re: Researches in quantum computing seem to progress only extremely slowly "Chris M. Thomasson" <nospam@nospam.nospam> - 2015-09-04 17:11 -0700
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-05 02:31 +0200
Re: Researches in quantum computing seem to progress only extremely slowly "Chris M. Thomasson" <nospam@nospam.nospam> - 2015-09-04 20:15 -0700
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 00:35 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 00:42 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 00:46 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 00:54 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 01:11 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 01:21 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 01:28 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 02:01 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 02:22 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 02:51 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 02:57 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 03:08 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 03:31 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 03:45 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 03:54 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 04:18 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-03 04:24 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Johannes Bauer <dfnsonfsduifb@gmx.de> - 2015-09-03 07:23 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 16:14 -0500
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-02 23:23 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Kaz Kylheku <kaz@kylheku.com> - 2015-09-02 21:33 +0000
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-02 23:54 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-02 23:22 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-02 23:32 +0200
Re: Researches in quantum computing seem to progress only extremely slowly bartekltg <bartek@gmail.com> - 2015-09-03 00:22 +0200
Re: Researches in quantum computing seem to progress only extremely slowly "Chris M. Thomasson" <nospam@nospam.nospam> - 2015-09-01 13:23 -0700
Re: Researches in quantum computing seem to progress only extremely slowly Mok-Kong Shen <mok-kong.shen@t-online.de> - 2015-09-02 11:04 +0200
Re: Researches in quantum computing seem to progress only extremely slowly Robert Wessel <robertwessel2@yahoo.com> - 2015-09-02 02:22 -0500
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