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-   -   Did I not explain it very well? (http://www.homecinemabanter.com/showthread.php?t=69007)

J G Miller[_4_] April 6th 11 03:30 PM

Not such a small problem...
 
On Wednesday, April 6th, 2011 at 02:58:46h +0100, Johny B Good wrote:

Once the whole universe is at exactly the same temperature
it will become impossible to create this condition.


If everything is at the same temperature, is everything in
a constant steady state?

And if so, has time effectively stopped?

J G Miller[_4_] April 6th 11 03:37 PM

Not such a small problem...
 
On Wednesday, April 6th, 2011 at 08:46:49h +0100, Jim Lesurf explained:

The bad news is that they only sell return tickets and require you to
have a visa from your destination.


It is always the bureaucratic paper work that ruins any escape plans ...

Meanwhile NASA are getting their new rover vehicle, Curiosity, ready
for a planned launch later this year.

http://news.cnet.COM/2300-11386_3-10007302.html?tag=mncol

Curiosity seeks clues to microbial Martian life April 6th, 2011

I hope they got the necessary licensing and road tax paperwork approved
by the Martian authorities. ;)

Peter Duncanson April 6th 11 03:43 PM

Not such a small problem...
 
On Wed, 6 Apr 2011 13:30:22 +0000 (UTC), J G Miller
wrote:

On Wednesday, April 6th, 2011 at 02:58:46h +0100, Johny B Good wrote:

Once the whole universe is at exactly the same temperature
it will become impossible to create this condition.


If everything is at the same temperature, is everything in
a constant steady state?

And if so, has time effectively stopped?


I don't think so. If the temperature is above absolute zero, atoms and
molecules will be flying around (gas) and vibrating (fluids and solids).
That's what heat is.

If things are moving there must be time for the motion to happen in.

--
Peter Duncanson
(in uk.tech.digital-tv)

J G Miller[_4_] April 6th 11 03:57 PM

Not such a small problem...
 
On Wednesday, April 6th, 2011 at 14:43:35h +0100, Peter Duncanson wrote:

If the temperature is above absolute zero, atoms and
molecules will be flying around (gas) and vibrating (fluids and solids).
That's what heat is.


Yes if the temperature is above 0 kelvins then atoms will indeed be
vibrating.

But if atoms and molecules are flying around, that means that there
is the possibility of collisions and a miniscule possibility of a chemical
reaction occurring between two different molecules and thus in some cases
an exothermic reaction with the release of energy.

Are you certain that atoms and molecules would still be moving around
other than just having vibrational motion?

If things are moving there must be time for the motion to happen in.


True.

I think my question was framed in a more philosophical frame of mind,
along the lines of "if a tree fell in the woods and nobody was there,
would it make a noise."

Thus if nothing was moving other than the atoms vibrating, which in this
scenario an observer is deemed not to be able to detect or measure,
would time effectively stand still since there would never be any
observable change from any reference point?

Jim Lesurf[_2_] April 6th 11 04:04 PM

Not such a small problem...
 
In article , Peter Duncanson
wrote:
On Wed, 6 Apr 2011 13:30:22 +0000 (UTC), J G Miller
wrote:


On Wednesday, April 6th, 2011 at 02:58:46h +0100, Johny B Good wrote:

Once the whole universe is at exactly the same temperature it will
become impossible to create this condition.


If everything is at the same temperature, is everything in a constant
steady state?

And if so, has time effectively stopped?


I don't think so. If the temperature is above absolute zero, atoms and
molecules will be flying around (gas) and vibrating (fluids and solids).
That's what heat is.


If things are moving there must be time for the motion to happen in.


But how will you know what time it is, and measure how much time has passed
since the last sic? time you did so? :-)

The situation isn't simply that everything is at the "same temperature". It
is that everything is disorganised and with no signs of any patterns.
Including your 'clock'. Even if you had a clock[1], what would happen when
its batteries ran flat? :-)

[1] Thus meaning you hadn't *yet* reach the end-state predicted for the
universe, so time was still observable.

Slainte,

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html


Peter Duncanson April 6th 11 05:28 PM

Not such a small problem...
 
On Wed, 6 Apr 2011 13:57:12 +0000 (UTC), J G Miller
wrote:

On Wednesday, April 6th, 2011 at 14:43:35h +0100, Peter Duncanson wrote:

If the temperature is above absolute zero, atoms and
molecules will be flying around (gas) and vibrating (fluids and solids).
That's what heat is.


Yes if the temperature is above 0 kelvins then atoms will indeed be
vibrating.

But if atoms and molecules are flying around, that means that there
is the possibility of collisions and a miniscule possibility of a chemical
reaction occurring between two different molecules and thus in some cases
an exothermic reaction with the release of energy.

Are you certain that atoms and molecules would still be moving around
other than just having vibrational motion?

That would depend on the temperature. You postulated a situation in
which "everything is at the same temperature" without suggesting a
temperature. If it is high enough for gases to exist then atoms and
molecules will be flying around. I don't know how cold things need to be
for all stuff to be in liquid or solid form.

If things are moving there must be time for the motion to happen in.


True.

I think my question was framed in a more philosophical frame of mind,
along the lines of "if a tree fell in the woods and nobody was there,
would it make a noise."

Thus if nothing was moving other than the atoms vibrating, which in this
scenario an observer is deemed not to be able to detect or measure,
would time effectively stand still since there would never be any
observable change from any reference point?


I think we need a physicist of the right specialization to answer that
question!

--
Peter Duncanson
(in uk.tech.digital-tv)

Bill Wright[_2_] April 6th 11 05:29 PM

Not such a small problem...
 
Johny B Good wrote:

Will the telly still work?


Nothing will work. For something to 'work' (eg raise a 1Lb mass through
a height difference of 33,000 feet in one minute represents a storage of
44.76Kj of potential energy or work at the rate of 1 horsepower for 1
minute) you need some means of hijacking energy on its travels to
oblivion which essentially requires a temperature difference to be
maintained. Once the whole universe is at exactly the same temperature
it will become impossible to create this condition.


I'm sure what you say is right young man, but all I want to know is,
will the telly be off for long? Will it be off when 'Doctors' is on?
Will we be able to record programmes while it's off? When you've
finished will you come to mine and make sure it's come back on? I'll
make you a nice cup of tea...

Bill

Mark Carver April 6th 11 05:53 PM

Not such a small problem...
 
On 06/04/2011 01:28, Johny B Good wrote:
The ultimate fate of our universe couldn't get any bleaker.


I can tell; you're one of those; "The bottle is half empty" pessimist
types ?


--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

J G Miller[_4_] April 6th 11 06:52 PM

Not such a small problem...
 
On Wednesday, April 6th, 2011 at 16:28:07h +0100, Peter Duncanson wrote:

I don't know how cold things need to be for all stuff to be in
liquid or solid form.


Well one estimated final temperature of the universe is from

http://math.ucr.edu/home/baez/end.html

QUOTE

At this point the cosmic background radiation will have cooled to about 10-13 Kelvin,
and most things will be at about that temperature unless proton decay or some other
such process keeps them warmer.

...

If we make a rough guess at the cosmological constant, the temperature we get is
about 10-30 Kelvin.

UNQUOTE

So 10^-13 kelvins is certainly cold enough for most stuff to be in solid form,
even more so if the temperature dips further to 10^-30 kelvins.

The current measured temperature of the universe is 2.726 kelvins

http://www.sciencemag.ORG/content/262/5135/861.short

which is cold enough for most things to be a solid -- freezing point
of helium is 4.22 kelvins.

J G Miller[_4_] April 6th 11 06:55 PM

Not such a small problem...
 
On Wednesday, April 6th, 2011 at 15:04:07h +0100, Jim Lesurf wrote:

It is that everything is disorganised and with no signs of any patterns.
Including your 'clock'.


But we all know that by putting an observer into a system and taking
a measurement, the system is changed just by doing that, so it
becomes a "catch 22" situation.


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