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Groups > comp.programming > #5768
| 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 02:57 +0200 |
| Organization | albasani.net |
| Message-ID | <ms85tu$68u$1@news.albasani.net> (permalink) |
| References | (13 earlier) <ms80a0$nte$1@speranza.aioe.org> <ms80n3$28p$1@news.albasani.net> <ms82jv$rqr$1@speranza.aioe.org> <ms83rh$2tp$3@news.albasani.net> <ms85il$ur$1@speranza.aioe.org> |
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.
M. K. Shen
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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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