Re: Arrow of time


"Dr Umesh Bilagi" <umeshbilagi@xxxxxxxxx> wrote in message
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On May 3, 11:11 am, "Ross Langerak" <rlange...@xxxxxxxxxxxxx> wrote:
"Dr Umesh Bilagi" <umeshbil...@xxxxxxxxx> wrote in
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On May 2, 7:28 am, "Ross Langerak" <rlange...@xxxxxxxxxxxxx> wrote:
"Dr Umesh Bilagi" <umeshbil...@xxxxxxxxx> wrote in
messagenews:1178030686.129271.139890@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx

linkhttp://umeshbilagi.blogspot.com/2007/04/arrow-of-time.html
Why should any body accept that order & disorder are different
quanties?

They shouldn't. Nor should they accept that they are the same.

I assume that you are referring to entropy and the Second Law of
Thermodynamics (SLoT). The SLoT is a statement about entropy. In
thermodynamics, order and disorder are not scientifically defined
terms.
They are sometimes used to give students new to the subject a feel for
entropy. As we can see from your examples, because order and disorder
are
not scientifically defined, they can be interpreted in often
contradictory
ways.

It is manifestation of our pchycology. As a physical quantity there
is
no difference.Both are different possibilties of arrangemnt of units

Example:- Drop a glass it breaks to small pieces, even broken
pieces,
may look like some from of design for some people. So order &
disorder
not necessarily different states. It is how we look at it & how much
benfit they give us

Now Look at Super nova to be a disorder & formation of planets &
next
genaration star from supernova to be order. we all know that
supernova
& formation of planets is frequent phenomena. Now if order &
disorder
are physcical quantities than genaraly order does not come from
disorder it more often incerases with time. How is this ?
So I think order & disorder or not physical quantites which can be
calculated. there are our perceptions depending on how we look at
them-
Hide quoted text -

- Show quoted text -

Wher is entropy increasing supernova folwoed by formation palnets &
stars
if entropy mean energy disperasal

Entropy does not mean energy dispersal. That is another phrase used for
introducing the concept of entropy. In classical thermodynamics, a
change
in entropy is defined by an equation. This equation tells us two things
relevant to this discussion. First, a heat engine produces work by
moving
heat from a hot source to a cold sink. The movement of the heat results
in
an increase in entropy. And second, decreasing entropy - moving heat
from a
cold sink to a hot reservoir - requires an input of work.

I AM VERY IMPREESED WITH YOUR ANSWER

Applied to the formation of a star and planets, a cloud of dust and gas
collapses under its own gravity. Potential energy is turned into kinetic
energy and then heat. The hot star and planets radiate heat out into the
cold Universe. This represents an increase in entropy. To reverse
this -
to return the system to a diffuse cloud of dust and gas - would require
an
input of work. The cloud of dust and gas is the low entropy condition;
the
planetary system is the high entropy condition.

ALL the heat produced formation gets dispeated if then why core of
earth is still hot
I may asking very useless question please tell me

Radioactive decay (fission) of heavy elements (uranium, thorium, potassium).

The same thing happens in a supernova, except it happens on the nuclear
level. Smaller nuclei fuse to produce larger nuclei and heat. When this
happens during a supernova, heavy elements are produced that are then
driven
off along with other gases. The materials that are driven off represent
a
decrease in entropy. However, to undo the fusing of nuclei that occurs
in
the heart of a star would require an input of work and a change in
entropy
that far outweighs the entropy decrease in the expelled materials. Thus
both a supernova and the formation of a planetary system are processes
the
produce an overall increase in entropy.- Hide quoted text -

- Show quoted text -

I am understanding why expeled matter repreasent decreased entropy
Thanks for answering


.

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