On 6/16/2012 9:56 AM, John Clark wrote:
On Fri, Jun 15, 2012 Craig Weinberg <whatsons...@gmail.com
<mailto:whatsons...@gmail.com>> wrote:
>> It's true that as I've described it using nothing but English it
does sound a
little subjective and vague about where exactly the transition between
micro and
macro states occurs, however if you use mathematics you can become much
more
rigorous and show that for some things, like a bucket of water,
changes at
smaller and smaller scales produce exponentially smaller changes at
larger and
larger scales; while for other things, like a perfect diamond, that
effect is
much less pronounced.
> Less pronounced to whom though?
Less pronounced for anyone using the lens of mathematics. As the scale of changes
becomes smaller the result of those changes becomes smaller at larger scales, and they
do so in a way that can be precisely calculated with statistical methods. Depending on
how many of these small scale changes exist that lead to small changes at larger scales
is how we determine if something has high or low entropy.
> If a seed falls in a bucket of water, the water becomes part of an
entropy
reducing plant.
A plant may reduce entropy locally but it can't do so globally, nothing can do that,
entropy stays the same or increases, it never decreases.
> If you look at the water over 10,000 years, you might see many low
entropy forms,
clouds, ice, etc while the diamond has comparatively high average entropy.
No idea what you're talking about.
> No, it depends on sense and participation. Information is a second order
sense of
a primary sense, derived through measurement, memory, inference, etc.
So a 100 carat diamond must be exactly the same thing as a charcoal briquette of the
same weight because they are both made of nothing but carbon atoms and neither the
diamond nor the charcoal can sense anything. Or are you a fan of solipsism and think
that nothing exists until you look at it, if so then you must believe that information
is even more important than I do because the ONLY thing that you or I or anybody can
understand is information, so if only what you understand exists then only information
exists.
>> Bad example, MPEG and JPEG files deliberately loose information
that, due to
the particular nature of the human visual system, make a only a small
contribution, considering their large size, to the look of the final
movie or
picture. A Martian who's eyes work differently might throw away
different
information. We should use lossless compression algorithms like GIF or
ZIP in
examples like this.
>No, that's exactly why it's a good example. It shows how information is
subjective.
The quality of information is subjective but it's quantity is not. It is objectively
true that there is more information in a bucket of water than in the DNA of your body,
but most human beings would consider it's quality to be much much less because they
don't care what a particular water molecule in that bucket is doing.
> A Martian microscope might work differently might see movie stars
pictures inside
of molecules that ours miss.
If the Martian is mathematically literate he could tell how much information was in the
image he was studying and we Earth people would agree with him on that figure, although
we might disagree about what parts of the image are important and what parts are not.
And a Martian would know the difference between a lossless compression program and a
lossy one and he would know that if he used the lossy one there would not be enough
information to exactly reproduce the original picture or movie or sound or martian
klogknee or whatever the information is encoded for.
Neither science nor mathematics can take sides in matters of taste, physics can tell you
how to build a bridge that won't fall down but it can't tell you if building a bridge is
something worth doing.
> Warm water has more physical entropy than ice, but a movie of ice melting
has more
information entropy than a movie of water, if you use any sort of
compression. That
was my whole point.
You're whole point was that a movie of something is more objective and in your opinion
more important than the real thing?
> blue cannot be seen by the blind, no matter how convincingly we describe
it to them
You don't know that, nobody can know that. You can see blue without light in a jet black
room just by putting pressure on your eyeball, perhaps the blind see blue all the time
but they just don't know it's the same thing we mean when we say "blue".
> The point is, that no scheme of compression or treatment of information
has
anything to do with the physical entropy of an actual substance.
I'd say mathematical and physical entropy have one hell of a lot to do with each other!
Mathematical compression programs work by getting rid of redundancy in files, the more
redundancy they have, that is to say the less entropy in them, the better they work;
they don't work at all on white noise. A physical crystal with its atoms all lined up in
a regular lattice has a lot of redundancy and thus little entropy, a bucket of water
with its molecules bumping around chaotically has much less redundancy and much more
entrophy.
Or have a look at:
arXiv:1009.1630v2 <http://arxiv.org/abs/1009.1630v2> [quant-ph]
*The thermodynamic meaning of negative entropy*
Lídia del Rio <http://arxiv.org/find/quant-ph/1/au:+Rio_L/0/1/0/all/0/1>, Johan Aberg
<http://arxiv.org/find/quant-ph/1/au:+Aberg_J/0/1/0/all/0/1>, Renato Renner
<http://arxiv.org/find/quant-ph/1/au:+Renner_R/0/1/0/all/0/1>, Oscar Dahlsten
<http://arxiv.org/find/quant-ph/1/au:+Dahlsten_O/0/1/0/all/0/1>, Vlatko Vedral
<http://arxiv.org/find/quant-ph/1/au:+Vedral_V/0/1/0/all/0/1>
(Submitted on 8 Sep 2010 (v1 <http://arxiv.org/abs/1009.1630v1>), last revised 27 Jun 2011
(this version, v2))
Landauer's erasure principle exposes an intrinsic relation between
thermodynamics and
information theory: the erasure of information stored in a system, S,
requires an
amount of work proportional to the entropy of that system. This entropy,
H(S|O),
depends on the information that a given observer, O, has about S, and the
work
necessary to erase a system may therefore vary for different observers.
Here, we
consider a general setting where the information held by the observer may be
quantum-mechanical, and show that an amount of work proportional to H(S|O)
is still
sufficient to erase S. Since the entropy H(S|O) can now become negative,
erasing a
system can result in a net gain of work (and a corresponding cooling of the environment).
Where is shown explicitly how extract energy by erasing information.
Brent
> You can't compress the substance, because it is not information.
Information is a
subjective (or intersubjective) measurement, nothing more and nothing less.
If information is just subjective then when you've had a few too many drinks and a
charcoal briquette starts to look like a diamond to you then it really is a diamond
because the only difference between the two is the information on how the carbon atoms
are arranged. If your above statement is true then it is also objectively true that you
Craig Weinberg can turn charcoal into diamond with nothing but the power of your mind.
Sounds like a comic book superhero.
John K Clark
--
You received this message because you are subscribed to the Google Groups "Everything
List" group.
To post to this group, send email to everything-list@googlegroups.com.
To unsubscribe from this group, send email to
everything-list+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/everything-list?hl=en.
--
You received this message because you are subscribed to the Google Groups
"Everything List" group.
To post to this group, send email to everything-list@googlegroups.com.
To unsubscribe from this group, send email to
everything-list+unsubscr...@googlegroups.com.
For more options, visit this group at
http://groups.google.com/group/everything-list?hl=en.
