[TUHS] RIP Claude Shannon

[TUHS] RIP Claude Shannon

[Doug McIlroy]

> But a note on Dijkstra's algorithm: Moore and Dijsktra both published
> in 1959.

I was off by one on the year, but the sign of the error is debatable.

Moore's paper was presented in a conference held in early April, 1957,
proceedings from which were not issued until 1959. I learned about it
from Moore when I first I met him, in 1958. Then, he described the
algorithm in vivid, instantly understandable terms: imagine a flood
spreading at uniform speed through the network and record the
distance to nodes in order of wetting.

> But it is documented Dijkstra's algorithm has been invented and used
> by him in 1956.

Taking into account the lead time for conference submissions, one
can confidently say that Moore devised the algorithm before 1957.
I do not know, though, when it first ran on a Bell Labs computer.

That said, Moore's paper, which presented the algorithm essentially
by example, was not nearly as clear as the capsule summary he gave
me. It seems amateurish by comparison with Dijkstra's elegant treatment.
Dijkstra's name has been attached to the method with good reason.

Doug

[TUHS] RIP Claude Shannon

[Otto Moerbeek]

On Sun, Feb 25, 2018 at 08:16:36AM -0500, Doug McIlroy wrote:

> > But a note on Dijkstra's algorithm: Moore and Dijsktra both published
> > in 1959.
> 
> I was off by one on the year, but the sign of the error is debatable.
> 
> Moore's paper was presented in a conference held in early April, 1957,
> proceedings from which were not issued until 1959. I learned about it
> from Moore when I first I met him, in 1958. Then, he described the
> algorithm in vivid, instantly understandable terms: imagine a flood
> spreading at uniform speed through the network and record the
> distance to nodes in order of wetting.
> 
> > But it is documented Dijkstra's algorithm has been invented and used
> > by him in 1956.
> 
> Taking into account the lead time for conference submissions, one
> can confidently say that Moore devised the algorithm before 1957.
> I do not know, though, when it first ran on a Bell Labs computer.
> 
> That said, Moore's paper, which presented the algorithm essentially
> by example, was not nearly as clear as the capsule summary he gave
> me. It seems amateurish by comparison with Dijkstra's elegant treatment.
> Dijkstra's name has been attached to the method with good reason.
> 
> Doug

On the subject of independent (re)discovery, it is interesting to note
that the second problem in Dijkstra's paper describes a solution to
the minimum spanning tree problem that was already pubslished in 1957
by Prim and in 1930 by Jarnik. I guess that in those days searching for
existing solutions wasn't as easy as it is now.

	-Otto

[TUHS] RIP Claude Shannon

[Dave Horsfall]

On Mon, 26 Feb 2018, Doug McIlroy wrote:

> More memories: Fano was among the grad students who came to ice-skating 
> parties at our house in the mid-40s--the house near Shannon's later 
> abode. I did not really get to know him until Multics days. His gravelly 
> mafioso voice would scare you off--until you saw the irrepressible 
> twinkle in his eye. A beloved and inspiring leader, worthy of Dave 
> Horsfall's calendar.

Noted; thank you!  More additions are welcome, of course.

-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."

[TUHS] RIP Claude Shannon

[Doug McIlroy]

> [Bob Fano}  still has a reverential photograph of Shannpn
> hanging in his office.

Alas, no, Fano died in 2016 at age 98.

More memories: Fano was among the grad students who came to 
ice-skating parties at our house in the mid-40s--the house near
Shannon's later abode. I did not really get to know him until
Multics days. His gravelly mafioso voice would scare you off--until
you saw the irrepressible twinkle in his eye. A beloved and
inspiring leader, worthy of Dave Horsfall's calendar.

Doug

[TUHS] RIP Claude Shannon

[Bakul Shah]

Mitchell Waldrop's "The Dream Machine: J. C.  R. Licklider and
the Revolution That Made Computing Personal" book has probably
been discussed on this list in the past. It has pages full of
fascinating stuff about Claude Shannon & his work. For instance:

  "A Symbolic Analysis of Relay and Switching Circuits" has
  just the kind of cerebral exuberance you'd expect from a
  very bright twenty-one-year-old. Shannon's thesis is
  downright fun to read--and strangely compelling, given
  what's happened in the six decades since it was written.
	...
  That ability, in turn, is ultimately what makes a modern
  digital computer so much more than just an adding machine:
  it can work its way through a sequence of such decisions
  automatically. In a word, it can be programmed. And that's
  why "A Symbolic Analysis of Relay and Switching Circuits" is
  arguably the most influential master's thesis of the
  twentieth century: in it Claude Shannon laid the theoretical
  foundation for all of modern computer design
	...
  Legend has it that Claude Shannon published "A Mathematical
  Theory of Communication" in 1948 only because his boss at
  Bell Labs finally badgered him into it. And whatever the
  truth of that story, the point is that no one who knew
  Shannon has any trouble believing it.

  "He wrote beautiful papers--when he wrote," says Robert
  Fano, who became a leader of MIT's information-theory group
  in the 1950s and still has a reverential photograph of
  Shannon hanging in his office. "And he gave beautiful talks-
  when he gave a talk.  But he hated to do it."

  It wasn't a matter of Shannon's being lazy, Fano says; he
  was constantly filling up notebooks with ideas, theorems,
  and calculations. He just wouldn't publish--or not very
  often, anyway. No, Shannon's reticence seems to have been
  more a matter of extraordinary self-sufficiency.

and much more. A book well worth reading.

[TUHS] RIP Claude Shannon

[Charles H Sauer]

Of course -- wonder how many people have read that as intended vs. what it 
says.

-----Original Message----- 
From: Mike Markowski
Sent: Sunday, February 25, 2018 6:44 AM
To: tuhs at minnie.tuhs.org
Subject: Re: [TUHS] RIP Claude Shannon

Maybe more accurate, "cannot be *overstated*"?  :-)

- Mike Markowski

On 02/24/2018 07:03 PM, Charles H Sauer wrote:
> In the early 70s I became aware of Shannon, the Nyquist Theorem, and 
> digital audio, and naively started collecting TTL parts to try to build my 
> own music computer (I still have bags of those parts in the garage...).
>
>  From 
> http://www.indiana.edu/~emusic/etext/digital_audio/chapter5_digital.shtml: 
> "Twenty years later, Claude Shannon, mathematician and early computer 
> scientist, also working at Bells Labs and then M.I.T., developed a proof 
> for the Nyquist theory (thereby making it a theorem)*. The importance of 
> their work to information theory, computing, networks and digital audio 
> cannot be understated."
>
> CHS
>
> -----Original Message----- From: Dave Horsfall
> Sent: Friday, February 23, 2018 3:44 PM
> To: The Eunuchs Hysterical Society
> Subject: [TUHS] RIP Claude Shannon
>
> We lost Claude Shannon on this day in 2001.  He was a mathematician,
> electrical engineer, and cryptographer; he is regarded as the "father" of
> information theory, and he pioneered digital circuit design.  Amongst
> other things he built a barbed-wire telegraph, the "Ultimate Machine" (it
> reached up and switched itself off), a Roman numeral computer ("THROBAC"),
> the Minivac 601 (a digital trainer), a Rubik's Cube solver, a mechanical
> mouse that learned how to solve mazes, and outlined a chess program
> (pre-Belle).  He formulated the security mantra "The enemy knows the
> system", and did top-secret work in WW-2 on crypto and fire-control
> systems.
> 

[TUHS] RIP Claude Shannon

[Mike Markowski]

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Maybe more accurate, "cannot be *overstated*"?  :-)

- Mike Markowski

On 02/24/2018 07:03 PM, Charles H Sauer wrote:
> In the early 70s I became aware of Shannon, the Nyquist Theorem, and 
> digital audio, and naively started collecting TTL parts to try to build 
> my own music computer (I still have bags of those parts in the garage...).
> 
>  From 
> http://www.indiana.edu/~emusic/etext/digital_audio/chapter5_digital.shtml: 
> "Twenty years later, Claude Shannon, mathematician and early computer 
> scientist, also working at Bells Labs and then M.I.T., developed a proof 
> for the Nyquist theory (thereby making it a theorem)*. The importance of 
> their work to information theory, computing, networks and digital audio 
> cannot be understated."
> 
> CHS
> 
> -----Original Message----- From: Dave Horsfall
> Sent: Friday, February 23, 2018 3:44 PM
> To: The Eunuchs Hysterical Society
> Subject: [TUHS] RIP Claude Shannon
> 
> We lost Claude Shannon on this day in 2001.  He was a mathematician,
> electrical engineer, and cryptographer; he is regarded as the "father" of
> information theory, and he pioneered digital circuit design.  Amongst
> other things he built a barbed-wire telegraph, the "Ultimate Machine" (it
> reached up and switched itself off), a Roman numeral computer ("THROBAC"),
> the Minivac 601 (a digital trainer), a Rubik's Cube solver, a mechanical
> mouse that learned how to solve mazes, and outlined a chess program
> (pre-Belle).  He formulated the security mantra "The enemy knows the
> system", and did top-secret work in WW-2 on crypto and fire-control
> systems.
> 

[TUHS] RIP Claude Shannon

[Charles H Sauer]

In the early 70s I became aware of Shannon, the Nyquist Theorem, and digital 
audio, and naively started collecting TTL parts to try to build my own music 
computer (I still have bags of those parts in the garage...).

From 
http://www.indiana.edu/~emusic/etext/digital_audio/chapter5_digital.shtml: 
"Twenty years later, Claude Shannon, mathematician and early computer 
scientist, also working at Bells Labs and then M.I.T., developed a proof for 
the Nyquist theory (thereby making it a theorem)*. The importance of their 
work to information theory, computing, networks and digital audio cannot be 
understated."

CHS

-----Original Message----- 
From: Dave Horsfall
Sent: Friday, February 23, 2018 3:44 PM
To: The Eunuchs Hysterical Society
Subject: [TUHS] RIP Claude Shannon

We lost Claude Shannon on this day in 2001.  He was a mathematician,
electrical engineer, and cryptographer; he is regarded as the "father" of
information theory, and he pioneered digital circuit design.  Amongst
other things he built a barbed-wire telegraph, the "Ultimate Machine" (it
reached up and switched itself off), a Roman numeral computer ("THROBAC"),
the Minivac 601 (a digital trainer), a Rubik's Cube solver, a mechanical
mouse that learned how to solve mazes, and outlined a chess program
(pre-Belle).  He formulated the security mantra "The enemy knows the
system", and did top-secret work in WW-2 on crypto and fire-control
systems.

-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will 
suffer." 

[TUHS] RIP Claude Shannon

[Rudi Blom]

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Never heard of Claude Shannon. So a good opportunity to do some
searching reading to 'catch up'.

Interesting person and this quota tends to make him my type of guy
"I just wondered how things were put together.
– C.E. Shannon"

http://themathpath.com/documents/ee376a_win0809_aboutClaudeShannon_willywu.pdf

Now wondering if I should register for this THORIAC project or just
read some more and do it. Not in the mood for learning Python I'd
probably do some fumbling in C.
https://www.engage-csedu.org/find-resources/shannons-throbac

Keeps me busy and amuzed,
uncle rubl

[TUHS] RIP Claude Shannon

[Dave Horsfall]

We lost Claude Shannon on this day in 2001.  He was a mathematician, 
electrical engineer, and cryptographer; he is regarded as the "father" of 
information theory, and he pioneered digital circuit design.  Amongst 
other things he built a barbed-wire telegraph, the "Ultimate Machine" (it 
reached up and switched itself off), a Roman numeral computer ("THROBAC"), 
the Minivac 601 (a digital trainer), a Rubik's Cube solver, a mechanical 
mouse that learned how to solve mazes, and outlined a chess program 
(pre-Belle).  He formulated the security mantra "The enemy knows the 
system", and did top-secret work in WW-2 on crypto and fire-control 
systems.

-- 
Dave Horsfall DTM (VK2KFU)  "Those who don't understand security will suffer."