Why is it that zero Kelvin (aka the point at which something being cold can reach it's maximum amount of coldness?)

[Magnetar_Byte]

My initial thought was that maybe because in essence cold isnt a thing it's merely the measurement of there not being energy there. So because of that, there is a limit to how cold something can get. Due to the fact if you have no more particles in a space that is the “Coldest” it will get. 

 

SOO this means

 

THERE IS no limit to there being something in a space. Aka heat. Because in essence u can always add more particles or energy to a place but you can't just keep removing particles. Because once you reach zero particles there is no more to remove. Hence the absolute zero bit) So heat aka the amount particles in an area can always go up until you can’t fit more particles into a space I suppose. Which I guess would be it's limit but it's not really one cause space is expanding so your container is just getting bigger as you try to reach it's limit. But  if the universe isn’t infinite then that would be the limit i guess.

 

Wrap up:

I really find this interesting. Because the way we all think of cold and hot is not AT ALL how we should. Rather then something being cold its just the lack of heat being there. So what this means is that once energy becomes so spread out in our universe as it will due to the FTL speed of the expansion of our universe. Heat or the energy we know needs to exist for what we know wouldn't exist. It would be IMPOSSIBLE to even exist due to how evenly spaced out particles are in this far future universe. 

 

So cool indeed...

 

[Zando_]

What.

 

also if heat is just adding more stuff to the same space, steel or water should be really really hot and the air should be fucking freezing due to the differing densities, aka more or less stuff in the same space? I thought heat was more how fast molecules and shit were vibrating or something like that, as it gets colder they slow down. Not sure if that was the cause or the effect though. 

[Magnetar_Byte]

*delete this reply*

[Zando_]

1 minute ago, Magnetar_Byte said:

Its me going through my thought process. Perhaps comment on the question or the result not the process.

 

This is the question though: "Why is that zero Kelvin aka the point at which something being cold can reach for it's maximum amount of coldness?"

Haven't the foggiest what that means, it's like you half-finished a thought then smacked 1/3 of another on the end and put a question mark last for good measure. 

[Magnetar_Byte]

6 minutes ago, Zando Bob said:

Also if heat is just adding more stuff to the same space, steel or water should be really really hot and the air should be fucking freezing due to the differing densities, aka more or less stuff in the same space?

What I'm saying is that a simple way to break down how heat works is that it depends on the amount of particles in a space. I'm leaving out the vibrations they need to be to produce heat because its irrelavent at this moment. Because its a constant that doesn't affect the outcome its just a switch u turn on.

6 minutes ago, Zando Bob said:

I thought heat was more how fast molecules and shit were vibrating or something like that, as it gets colder they slow down. Not sure if that was the cause or the effect though. 

It is refer back to above comment.

 

Particle amount is what is the cause of heat. Every object will vibrate at a specific amount what changes its heat is the amount of particles in it. Sure u can change it another way but that way aka increasing vibrations has limits where as adding particles doesn't. 

 

 

[Magnetar_Byte]

7 minutes ago, Zando Bob said:

This is the question though: "Why is that zero Kelvin aka the point at which something being cold can reach for it's maximum amount of coldness?"

Haven't the foggiest what that means, it's like you half-finished a thought then smacked 1/3 of another on the end and put a question mark last for good measure. 

fixed it

[Zando_]

12 minutes ago, Magnetar_Byte said:

What I'm saying is that a simple way to break down how heat works is that it depends on the amount of particles in a space. I'm leaving out the vibrations they need to be to produce heat because its irrelavent at this moment. Because its a constant that doesn't affect the outcome its just a switch u turn on.

It is refer back to above comment.

 

Particle amount is what is the cause of heat. Every object will vibrate at a specific amount what changes its heat is the amount of particles in it. Sure u can change it another way but that way aka increasing vibrations has limits where as adding particles doesn't. 

Then why is stuff like water or metal not boiling? It's quite dense, aka there's a shit ton of particles in the same space.

11 minutes ago, Magnetar_Byte said:

fixed it

"Why is it that Zero Kelvin?" makes no sense either. 
 

 

34 minutes ago, Magnetar_Byte said:

Because the way we all think of cold and hot is not AT ALL how we should. Rather then something being cold its just the lack of heat being there.

That has the same impact and depth as "peace is the absence of conflict". Of course cold is the same as lack of heat, that's how it works. Heat is just the lack of cold being there. Or you just call hot hot and cold cold, easy. 
 

35 minutes ago, Magnetar_Byte said:

So what this means is that once energy becomes so spread out in our universe as it will due to the FTL speed of the expansion of our universe. Heat or the energy we know needs to exist for what we know wouldn't exist. It would be IMPOSSIBLE to even exist due to how evenly spaced out particles are in this far future universe. 

W-what? Heat will cease to exist? We will cease to exist? what are you saying lmao. It seems like you're rambling to try and seem deep or some shit but you're really saying "universe is expanding" and "hot is not cold" which AFAIK have been known facts for a good while now. 

Also the universe expanding doesn't make stars or planets or anything else that's a tightly packed bunch of particles just cease existing? Doesn't it just make them farther apart?

[wasab]

There is no such thing as 0 Kelvin. A particle will always have some bits of thermal energy due to left over heat in cosmic microwave background from the big bang. Also due to the laws of thermal dynamic, energy will always flow from higher state to a lower state which means unless there are no particles or energy source around to transfer heat, a particle will not stay in lower temperature vs its surrounding for long. 

[HarryNyquist]

Just now, wasab said:

There is no such thing as 0 Kelvin. A particle will always have some bits of thermal energy due to left over heat in cosmic microwave background from the big bang. Also due to the laws of thermal dynamic, energy will always follow from higher state to a lower state which unless there are no particles or energy source around to transfer heat, a particle will not stay in lower temperature state vs it's surrounding for long. 

It's not that it doesn't exist. It's defined in the mathematics but it's very very hard to get to, both for the reasons you said regarding other hot things around, and also due to incredibly strange things happening at temperatures that low.

[wasab]

9 minutes ago, HarryNyquist said:

It's not that it doesn't exist. It's defined in the mathematics but it's very very hard to get to, both for the reasons you said regarding other hot things around, and also due to incredibly strange things happening at temperatures that low.

I don't see how it's mathematically possible by intuition. To drain a particle to 0 Kelvin, you need another particle with actual negative kelvins to do so. Any particle with none negative kelvins, including 0 Kelvin will only drain so much thermal energy until it becomes more energetic than the particle it drained from. 

This means if 0 Kelvin particle sees a 1 Kelvin particle, both end up with 0.5 kelvins. If 0.5 Kelvin sees 0 kelvins, both particles will end up with 0.25 klevins. You keep dividing by 2 to infinity and it goes to infintestinal but never reached absolute 0. This is assuming that there is this theoretical 0 klevin particle to drain energy from in the first place. 

 

I have never taken physics beyond college freshmen so if there is something I am missing here, please enlighten me. 

[Tamesh16]

FYI Negative Temperatures in kelvin Exists, but temperature is due the movement of particles (its kinetic energy) , not the amount present

[wasab]

Just now, Tamesh16 said:

FYI Negative Temperatures in kelvin Exists, but temperature is due the movement of particles (its kinetic energy) , not the amount present

If so, this means negative movement which is illogical. 

[Tamesh16]

4 minutes ago, wasab said:

If so, this means negative movement which is illogical. 

you have to know quite abit of physics to understand negative temperatures, but its essentially  what  makes 'temperature'  a measurable property 

but i mean you can google it, its not like i am making it up 

under thermodynamic models movement of particles is a basic generalization of temperature 

[wasab]

Just now, Tamesh16 said:

you have to know quite abit of physics to understand negative temperatures, but its essentially  what  makes 'temperature'  a measurable property 

What quantity as defined by movement can be lesser than 0 movement? Besides, just like Kelvin, kinetic energy can never be negative. 

[Tamesh16]

1 minute ago, wasab said:

What quantity as defined by movement can be lesser than 0 movement? Besides, just like Kelvin, kinetic energy can never be negative. 

i mean it is how it is, i am not going to explain the mathematical models of Entropy that allow cases of negative Kelvin temperatures, if you want to understand then you can do the research on your own, 

i mean i understand it might not make sense, but as i said earlier, the movement description of temperature is very basic and for models to work around what temperature is realistically they account for some negative temperature

[RAS_3885]

The fundamental point of OP is incorrect, since temperature (a.k.a thermal energy) is measured by the motion of molecules, not the total number of them.  Zero kelvin  exists because it's defined as the point where all molecular motion stops (as in no more thermal energy), but as stated above it's difficult to physically achieve.  Lots of scientific theories fall into the dilemma.

 

Vsauce has a fun video on the opposite... how hot can something get.  Since all things with temperature emit some sort of energy (measurable via the wavelength of said energy), you get to a certain point where the temp of something is so hot that the wavelength is equal to the Plank Distance, which is what we've called the smallest physical distance possible.  But what if you add more energy... the wavelength is supposed to get smaller, but physics also says it can't.  Our current known theories break down at that point.

[RAS_3885]

7 minutes ago, wasab said:

What quantity as defined by movement can be lesser than 0 movement? Besides, just like Kelvin, kinetic energy can never be negative. 

We have matter and anti-matter, but anti-matter is different than just the lack of matter.  This is why generalizations only make sense up to a certain point without going into PHD level understandings of the topic.

[wasab]

17 minutes ago, Tamesh16 said:

i mean it is how it is, i am not going to explain the mathematical models of Entropy that allow cases of negative Kelvin temperatures, if you want to understand then you can do the research on your own, 

i mean i understand it might not make sense, but as i said earlier, the movement description of temperature is very basic and for models to work around what temperature is realistically they account for some negative temperature

Is there such occurrence in real world though? Either artificial or natural? Or is it just some mathmatical convenience that physicsts come up with to satisfy an equation like say negative mass? 

[Tamesh16]

1 minute ago, wasab said:

Is there such occurrence in real world though?

we cant be sure as @RAS_3885 mentioned, its essentially because the model of temperature we have breaks down close to that extreme of the scale, 

so based on the 'movement' paradigm is doesn't seem like it, but only because we don't fully understand whats occurring close to zero kelvin 

the worse part is that objects with negative temperature are 'hotter' than normal positive temperature, so energy flows from the object with negative temperature to positive temperature and as such breaks down our understanding, 

i mean we work around it and use the phenomena to our advantage in lazers and such all the time, but we just dont fully understand it 

[RAS_3885]

3 minutes ago, wasab said:

Is there such occurrence in real world though? Either artificial or natural? Or is it just some mathmatical convenience that physicsts come up with to satisfy an equation like day negative mass? 

Nothing practical, but yes, it exists.  https://www.nature.com/news/quantum-gas-goes-below-absolute-zero-1.12146 as just one example from a quick Google search.

 

Generalizing, Kelvin scale represents the relationship between a system's internal energy and entropy.  Adding energy increases entropy (disorder), which we call positive temperature.  This is what

 

Systems can be created where adding energy causes the system to decrease it's entropy (move to a more ordered state).  This is what's called negative temperature on the absolute Kelvin scale.  Again, MASSIVE oversimplification here.