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  4. what is temperature?
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what is temperature?

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Offline Bored chemist

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Re: what is temperature?
« Reply #480 on: 17/07/2022 18:47:11 »
Quote from: puppypower on 17/07/2022 18:40:31
Quote from: alancalverd on 16/07/2022 12:33:54
Quote from: Bored chemist on 16/07/2022 12:15:35
All applied science is based on theoretical science
There is an admonitory adage in physics: "Thermodynamics owes more to the steam engine than the steam engine owes to thermodynamics", and the history of science bears that out.

If you subscribe to the "observe - hypothesise - test" model of scientific method, observation and experiment always precede theory and take precedence over it..

Applied science often begins by testing existing theory and new hypothesis. It is very rare that things work out as expected, with the first test. As problems appear and are overcome, the theory is modified at each iteration of experiments, until a new steady state is reached. Theoretical science may have to be modified to fit the data anomalies that keep coming. The final result is often protected, since the final application may have value in the free market.

I remember a development project I was given that involved developing a biological process, that could work under extreme circumstances. The  experts said it was not possible, based on the then current technology and theory. The final goal was to run an anaerobic experiment in a 2.5 million gallon open and leaky basin, with an initial composition that exceeded all known safe closed bio-reactors variable, by order of magnitude. My boss had faith in my ingenuity.

My first problem was I never took any biology courses in high school or  college. II like life but biology was to memory intensive and empirical for my tastes. I was good at organic chemistry, polymers, and engineering all of which are based on basic theory and ingenuity. So I had to teach myself a cram course in biology and bioreactors, and then follow my hunches in the lab, based on the POV of a biology outsider.

It turned out, I was a natural bacteria whisperer and the little bugs would help me out. I could get them go where they were not expected to go. To make a long story short, without any formal biology training, I was able to push the biology technology of the day, into the future.

My advantage was, I was not biased by the educational traditions that used a black box. My coursework as an engineer assumed something simple and more rational. When I looked at the project with my naive eyes, my bacteria were more robust than expected.

The final test of concept was my largest experiment of my career;  2.5 million gallons. It took 150 ton of powered limestone to neutralize the acid pond, I also gave bacteria steak to eat with a 5000 gallon tanker truck 100% acetic acid. I used about 30 gallons of concentrated phosphoric acid for the phosphate needs of DNA and RNA. It took about two weeks to kick in and ran like a charm and was done a few weeks later It even reduced heavy metal concentrations to discharge limits. This was part of a secondary trick using sulfuric acid that the bacteria would reduce to sulfide to form Heavy metal sulfides. This cause the pond to stick so I used an larger aerator to beat in oxygen until all the food was also gone. Good observation, logic and ingenuity can challenge theory based on consensus in a black box.

The tragic thing was, wha was a good thing, made many people angry. It altered the priority of a parallel engineering project; monument, that became obsolete. I felt political pressure afterwards and would eventually need to quit. I am less sensitive today. Now I fight and do not quit. Although I now try to be more diplomatic.

Temperature as a function of energy divided by entropy tells us how the energy is distributed based on the entropic information in the system. This allows for more complex modeling.

Picture a 1 mile cube in the atmosphere.l This is  gas that has clouds that phase separated from the oxygen and nitrogen and other trace gases like CO2. We are looking for the final temperature in the cube, based on adding X Kilojoules of energy to the cube.

Since entropy is not the same for the water cloud gas predicate, as the rest of the gas solution, the movement to steady temperature will not be straight forward. We will get some cooler spots, that will then need a secondary equilibration. This is not an ideal gas, but a mixture of gases and gas phase that can self segregate. My little equation can address this. The entropy data can be found in the CRC.
Did you realise that your story didn't actually tell us anything apart from the fact that, you needed to learn the theoretical aspect of biology in order to plan your project (which, incidentally sounds like a big heap of ... manure)?
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Offline puppypower

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Re: what is temperature?
« Reply #481 on: 17/07/2022 19:52:31 »
Quote from: Bored chemist on 17/07/2022 18:47:11
Quote from: puppypower on 17/07/2022 18:40:31
Quote from: alancalverd on 16/07/2022 12:33:54
Quote from: Bored chemist on 16/07/2022 12:15:35
All applied science is based on theoretical science
There is an admonitory adage in physics: "Thermodynamics owes more to the steam engine than the steam engine owes to thermodynamics", and the history of science bears that out.

If you subscribe to the "observe - hypothesise - test" model of scientific method, observation and experiment always precede theory and take precedence over it..

Applied science often begins by testing existing theory and new hypothesis. It is very rare that things work out as expected, with the first test. As problems appear and are overcome, the theory is modified at each iteration of experiments, until a new steady state is reached. Theoretical science may have to be modified to fit the data anomalies that keep coming. The final result is often protected, since the final application may have value in the free market.

I remember a development project I was given that involved developing a biological process, that could work under extreme circumstances. The  experts said it was not possible, based on the then current technology and theory. The final goal was to run an anaerobic experiment in a 2.5 million gallon open and leaky basin, with an initial composition that exceeded all known safe closed bio-reactors variable, by order of magnitude. My boss had faith in my ingenuity.

My first problem was I never took any biology courses in high school or  college. II like life but biology was to memory intensive and empirical for my tastes. I was good at organic chemistry, polymers, and engineering all of which are based on basic theory and ingenuity. So I had to teach myself a cram course in biology and bioreactors, and then follow my hunches in the lab, based on the POV of a biology outsider.

It turned out, I was a natural bacteria whisperer and the little bugs would help me out. I could get them go where they were not expected to go. To make a long story short, without any formal biology training, I was able to push the biology technology of the day, into the future.

My advantage was, I was not biased by the educational traditions that used a black box. My coursework as an engineer assumed something simple and more rational. When I looked at the project with my naive eyes, my bacteria were more robust than expected.

The final test of concept was my largest experiment of my career;  2.5 million gallons. It took 150 ton of powered limestone to neutralize the acid pond, I also gave bacteria steak to eat with a 5000 gallon tanker truck 100% acetic acid. I used about 30 gallons of concentrated phosphoric acid for the phosphate needs of DNA and RNA. It took about two weeks to kick in and ran like a charm and was done a few weeks later It even reduced heavy metal concentrations to discharge limits. This was part of a secondary trick using sulfuric acid that the bacteria would reduce to sulfide to form Heavy metal sulfides. This cause the pond to stick so I used an larger aerator to beat in oxygen until all the food was also gone. Good observation, logic and ingenuity can challenge theory based on consensus in a black box.

The tragic thing was, wha was a good thing, made many people angry. It altered the priority of a parallel engineering project; monument, that became obsolete. I felt political pressure afterwards and would eventually need to quit. I am less sensitive today. Now I fight and do not quit. Although I now try to be more diplomatic.

Temperature as a function of energy divided by entropy tells us how the energy is distributed based on the entropic information in the system. This allows for more complex modeling.

Picture a 1 mile cube in the atmosphere.l This is  gas that has clouds that phase separated from the oxygen and nitrogen and other trace gases like CO2. We are looking for the final temperature in the cube, based on adding X Kilojoules of energy to the cube.

Since entropy is not the same for the water cloud gas predicate, as the rest of the gas solution, the movement to steady temperature will not be straight forward. We will get some cooler spots, that will then need a secondary equilibration. This is not an ideal gas, but a mixture of gases and gas phase that can self segregate. My little equation can address this. The entropy data can be found in the CRC.
Did you realise that your story didn't actually tell us anything apart from the fact that, you needed to learn the theoretical aspect of biology in order to plan your project (which, incidentally sounds like a big heap of ... manure)?

I only studied for about a couple of weeks and decided to wing it. The goal was not to repeat the limitations of my peers, but make the project work, even if the current theory thought it could not work. The needed direction was not yet part of their literature, so I had to wing it. I started more empirical and observational until my 55-gallon drum evolved to my needs. I learned from that.

The only reason I was able to run the big test, was an emergency. The final test basin was reported in the local papers as a pollution hazard, and this news went up the chain, to state and then national EPA. I was the only one who could be ready to go in days, instead of months and years. I could improvise instead of buy off the shelf.

My project had actually been killed several months earlier. It made a come back because of these unique needs. I was invited to the big table meeting since the Plant Manager wanted all his options on the table. Nobody was willing to commit to anything, for the short term, until I spoke up and gave 5 to 1 odds it would work. I was disliked for this, since, after being killed,  I dared stepped on the toes.

The success of start up, helped the plant manager, since he was under a lot of stress. After all was done, he accepted the awards we received from the DOE, since it was a team effort, once it got going, from top to bottom. I was then reassigned to another big project.  They slowed me down with a long term project.

In retrospect, it was a career builder project, that could have lasted me to retirement. I was to develop all the needed science and technology to decommission the Lithium Isolate Separation Facility that was used in the 1950-60's to collect Lithium 6.  I must have been overdose by mercury, while exploring that historic facility. I lost my way with paranoia, so I had to quit, since I could not function properly and became off the wall.
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Offline Bored chemist

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Re: what is temperature?
« Reply #482 on: 17/07/2022 20:26:37 »
Quote from: puppypower on 17/07/2022 19:52:31
even if the current theory thought it could not work.
Is there actual evidence for the assertion that current theories said it couldn't work?
What are these theories?
Or are  you just reporting the views of some people who were basing their assessment on "practical experience"?
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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #483 on: 22/07/2022 09:27:36 »
Quote from: Bored chemist on 17/07/2022 09:17:58
Quote from: hamdani yusuf on 17/07/2022 08:46:38
Humans have been using fire long before they have a scientific model of fire. Boats have been widely used before Archimedes came up with theory of buoyancy. Arrows have been widely used before humans understand mechanics, gravity, and aerodynamic. 
Do you have any 21st century examples?
People usually don't realize that they don't understand or misunderstand how things work, especially if they can make them work. They will only realize when someone comes up with a better explanation.
« Last Edit: 22/07/2022 09:52:15 by hamdani yusuf »
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Offline Bored chemist

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Re: what is temperature?
« Reply #484 on: 22/07/2022 13:07:10 »
Quote from: hamdani yusuf on 22/07/2022 09:27:36
Quote from: Bored chemist on 17/07/2022 09:17:58
Quote from: hamdani yusuf on 17/07/2022 08:46:38
Humans have been using fire long before they have a scientific model of fire. Boats have been widely used before Archimedes came up with theory of buoyancy. Arrows have been widely used before humans understand mechanics, gravity, and aerodynamic. 
Do you have any 21st century examples?
People usually don't realize that they don't understand or misunderstand how things work, especially if they can make them work. They will only realize when someone comes up with a better explanation.
I presume that was a stupid way of saying "no".
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Offline Eternal Student

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Re: what is temperature?
« Reply #485 on: 22/07/2022 22:52:03 »
Hi.

  Apologies:     There's no way I've read all the posts since I last wrote something here.   It's just a quiet day and I'd like to join a discussion.

Quote from: alancalverd on 17/07/2022 13:32:59
Are you asking for an example of something people currently use but clearly don't understand?
    At a cursory glance, someone was asking for that (Bored Chemist ?) and someone was trying to provide examples (Hamdani Yusuf ?).    I think we can let Hamdani off the hook on that one and help out a bit.
    I don't have a crystal ball for seeing into the future but this seems like a safe enough bet:
Gravity   --->   This is a reasonable 21st century example of something we use but don't understand yet.   In particular we don't have a quantum theory gravity but it seems like a reasonable guess that there will be one.   If one is developed, it then seems undeniable that gravity wasn't exactly what we thought but we did have some models and approximations and were able to use it and even provide scientific and mathematical models for it that weren't too bad.

    About the rest of the thread:
   I'm still not sure where @hamdani yusuf  was going with this thread or what is left to discuss.   If you feel so inclined, it might be worth writing a short summary of what has been done so far and/or what you feel is missing or still needs to be done.    The thread is now 25 pages deep and if there were any new members joining, I'm sure they couldn't read all of that.

Best Wishes.
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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #486 on: 23/07/2022 04:15:26 »
Quote from: Bored chemist on 22/07/2022 13:07:10
Quote from: hamdani yusuf on 22/07/2022 09:27:36
Quote from: Bored chemist on 17/07/2022 09:17:58
Quote from: hamdani yusuf on 17/07/2022 08:46:38
Humans have been using fire long before they have a scientific model of fire. Boats have been widely used before Archimedes came up with theory of buoyancy. Arrows have been widely used before humans understand mechanics, gravity, and aerodynamic. 
Do you have any 21st century examples?
People usually don't realize that they don't understand or misunderstand how things work, especially if they can make them work. They will only realize when someone comes up with a better explanation.
I presume that was a stupid way of saying "no".

Lord Kelvin was as confident as you are about the scientific knowledge of his contemporaries.
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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #487 on: 23/07/2022 04:54:12 »
Quote from: Eternal Student on 22/07/2022 22:52:03
  I'm still not sure where @hamdani yusuf  was going with this thread or what is left to discuss.   If you feel so inclined, it might be worth writing a short summary of what has been done so far and/or what you feel is missing or still needs to be done.    The thread is now 25 pages deep and if there were any new members joining, I'm sure they couldn't read all of that.
I want to draw the line between what's called temperature and what's not temperature. So far, most of us agree that temperature is a kind of kinetic energy, which is related to motion. Thus a kind of energy not related to motion can not be called temperature.

On the other hand, not all kind of kinetic energy is called temperature. Uniform translational and rotational motions are not called temperature.  Electrons on a radio transmission antenna or a power distribution transformer may have high kinetic energy, but we don't usually say that they have high temperature. Measured from surface of the earth, ISS has high kinetic energy, but we don't usually say that it has high temperature. Audio speakers and ceiling fans are some other examples.

Alan offered an idea calling that kinetic energy causes change in temperature is called internal kinetic energy, and consequently,  external kinetic energy would not cause change in temperature. Unfortunately, we have not found a microscopic model which can be used to distinguish between internal and external kinetic energy to predict how a kind of movement would affect temperature measurement of an object. It means that for the time being, the distinction is not much better than semantics.
« Last Edit: 23/07/2022 09:33:39 by hamdani yusuf »
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Offline alancalverd

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Re: what is temperature?
« Reply #488 on: 23/07/2022 10:22:29 »
Quote from: hamdani yusuf on 23/07/2022 04:54:12
I want to draw the line between what's called temperature and what's not temperature.
Go back to page 1. Temperature is a measure of the internal kinetic energy of the constituents of a body.

Thew "microscopic model" you are looking for is simple. Any body is defined by its boundaries, and stuff is either inside or outside the boundary.

Your deliberate self-confusion should disappear once you remember that  speed is not absolute.The internal ke is a measure of the velocities of the constituent particles relative to each other, and the external ke is a measure of the mean group velocity of the whole body relative to the rest of the universe or whatever external frame of reference you choose.

Consider a 0.2 gram fly buzzing around at 1 m/s in an otherwise-empty car. It has 10-4  joules of kinetic energy relative to the shell of the car. If the car is travelling at 10 m/s over the ground, the fly has an additional 10-2 joules of kinetic energy relative to the planet.

For simplicity (because this is physics, not engineering) let the car have zero mass. If we lean the car gently against a wall, the fly could in principle transfer up to 10-4 joules of ke to the wall by crashing inelastically into the shell of the car. If we splatter the zero-mass car into the wall at 10 m/s, it will transfer 100 times as much energy, though the temperature of the car (the ke of the fly relative to the car) hasn't changed.

Now let's get practical. What has a zero-mass boundary? Any solid or liquid body. You can distinguish between inside and outside, and the boundary is the infinitesimal imaginary membrane between them.

What about gases, I ask, anticipating the next question of a troublemaker? Quite simply, you can't define the temperature of an unconfined gas because it will expand to fill the entire universe and the concept of average relative velocity will be meaningless. But you can obviously define the temperature of a bounded sample of gas or plasma.
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Offline Bored chemist

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Re: what is temperature?
« Reply #489 on: 23/07/2022 12:16:26 »
Quote from: hamdani yusuf on 23/07/2022 04:15:26
Lord Kelvin was as confident as you are about the scientific knowledge of his contemporaries.
And you confidently assert things that are clearly wrong.

Quote from: hamdani yusuf on 23/07/2022 04:54:12
Thus a kind of energy not related to motion can not be called temperature.
It quite often is.
The electronically excited neon atoms in a HeNe laser which emit light have a negative electronic temperature. Nobody cares much about their movement.
https://en.wikipedia.org/wiki/Negative_temperature#Lasers

You really need to stop ignoring reality.
« Last Edit: 23/07/2022 12:19:22 by Bored chemist »
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Offline Bored chemist

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Re: what is temperature?
« Reply #490 on: 23/07/2022 12:23:51 »
Quote from: hamdani yusuf on 23/07/2022 04:54:12
Electrons on a radio transmission antenna or a power distribution transformer may have high kinetic energy,
They might.
But only if the metal is hot.
And turning the transmitter on or off hardly affects their motion.

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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #491 on: 23/07/2022 15:31:30 »
Quote from: alancalverd on 23/07/2022 10:22:29
What about gases, I ask, anticipating the next question of a troublemaker? Quite simply, you can't define the temperature of an unconfined gas because it will expand to fill the entire universe and the concept of average relative velocity will be meaningless. But you can obviously define the temperature of a bounded sample of gas or plasma.
Does earth atmosphere have a boundary? What about Jupiter's or Venus'?
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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #492 on: 23/07/2022 15:37:37 »
Quote from: Bored chemist on 23/07/2022 12:16:26
And you confidently assert things that are clearly wrong.
Name one.
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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #493 on: 23/07/2022 15:47:14 »
Quote from: Bored chemist on 23/07/2022 12:16:26
The electronically excited neon atoms in a HeNe laser which emit light have a negative electronic temperature. Nobody cares much about their movement.
https://en.wikipedia.org/wiki/Negative_temperature#Lasers

You really need to stop ignoring reality.
The article says something about vortices momenta, which depend on their motion.
Quote
The possibility of negative temperatures was first predicted by Lars Onsager in 1949.[1] Onsager was investigating 2D vortices confined within a finite area, and realized that since their positions are not independent degrees of freedom from their momenta, the resulting phase space must also be bounded by the finite area.
How do you get a frequency without motion?
Quote
The Hamiltonian for a single mode of a luminescent radiation field at frequency ν is...
You really need to stop pretending to understand something that you don't.
« Last Edit: 23/07/2022 16:03:49 by hamdani yusuf »
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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #494 on: 23/07/2022 15:59:18 »
Quote from: Bored chemist on 23/07/2022 12:23:51
They might.
But only if the metal is hot.
And turning the transmitter on or off hardly affects their motion.
Have you ever worked with high powered radio transmission or power distribution transformers?
FYI, most of the power delivered to the antenna is not converted to heat.
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Offline alancalverd

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Re: what is temperature?
« Reply #495 on: 23/07/2022 19:19:00 »
So the temperature of the antenna is irrelevant.
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Offline Bored chemist

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Re: what is temperature?
« Reply #496 on: 23/07/2022 19:26:54 »
Quote from: hamdani yusuf on 23/07/2022 15:37:37
Name one.
I already named one of the things you confidently got wrong.
Quote from: Bored chemist on 23/07/2022 12:16:26
Quote from: hamdani yusuf on Today at 04:54:12
Thus a kind of energy not related to motion can not be called temperature.
It quite often is.
The electronically excited neon atoms in a HeNe laser which emit light have a negative electronic temperature. Nobody cares much about their movement.
https://en.wikipedia.org/wiki/Negative_temperature#Lasers


Did you not understand it?
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Offline Bored chemist

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Re: what is temperature?
« Reply #497 on: 23/07/2022 19:29:26 »
Quote from: hamdani yusuf on 23/07/2022 15:59:18
Have you ever worked with high powered radio transmission or power distribution transformers?
Yes, I have.

Now, here are a couple of questions for you.
What is the typical thermal velocity of an electron in a conductor near room temperature and
What is the drift velocity of an electron in a typical conductor in a transformer or antenna?
I don't need any great precision- just order of magnitude is fine.
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Re: what is temperature?
« Reply #498 on: 23/07/2022 19:35:28 »
Quote from: hamdani yusuf on 23/07/2022 15:47:14
The article says something about vortices momenta, which depend on their motion.
The relevant bit talks about an electronic population inversion in a laser.

I'm sorry the article is long and has other things that distracted you.

Here is the bit you need to focus on.

"This phenomenon can also be observed in many lasing systems, wherein a large fraction of the system's atoms (for chemical and gas lasers) or electrons (in semiconductor lasers) are in excited states. This is referred to as a population inversion."
"β must itself be negative, implying a negative temperature."

Once you recognise that the laser as a whole does not have a negative temperature, and that a negative temperature can't be due to a negative kinetic energy (because, even if the particles all suddenly moved backwards, their energies would still be positive), you will see that it's the electronic temperature which is negative, and that isn't due to the kinetic energies of the particles.

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Offline hamdani yusuf (OP)

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Re: what is temperature?
« Reply #499 on: 24/07/2022 07:47:33 »
Quote from: Bored chemist on 23/07/2022 19:26:54
Quote from: hamdani yusuf on 23/07/2022 15:37:37
Name one.
I already named one of the things you confidently got wrong.
Quote from: Bored chemist on 23/07/2022 12:16:26
Quote from: hamdani yusuf on Today at 04:54:12
Thus a kind of energy not related to motion can not be called temperature.
It quite often is.
The electronically excited neon atoms in a HeNe laser which emit light have a negative electronic temperature. Nobody cares much about their movement.
https://en.wikipedia.org/wiki/Negative_temperature#Lasers


Did you not understand it?
If the electrons stop moving, will they still have negative temperature?
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