B Is relativity universal?

  • Thread starter Noah332
  • Start date
29
0
Summary
What i mean is, for example, the zeroth law of thermodynamics states the if systems A and C are in thermal equilibrium with a system B, then A and C are in thermal equilibrium. Does this mean temperature is relative? Can relativity be applied to other aspects of physics and science in general?
Im just asking this general question.
 
97
43
Temperature is a measure of the average heat or thermal energy of particles in a substance. There is a scale - Kelvin - for this, with absolute zero being a theoretical point where there is zero thermal energy (there is no known corresponding maximum temperature that I'm aware of).

So temperature is not 'relative' unless you are comparing items against each other, as your A, B, and C systems suggests.

As far as we can measure, the laws of thermodynamics and the definition of temperature apply equally across the universe.

Now relativity, if defined as "the state of being judged in comparison with other things and not by itself", is applied to other aspects of physics and science in general.

However, relativity, if taken in the context of Einstein’s theories of of Special Relativity and General Relativity, have a very specific meaning that it does not appear that you are referring to, or alluding to, here.
 
29
0
I see where your getting at, but Im wondering if we rethought about things similar to how Einstein thought of relativity could that change our understanding of the universe and would that make it more easier to combine the standard model and GR?
 

Drakkith

Staff Emeritus
Science Advisor
2018 Award
20,440
4,135
I see where your getting at, but Im wondering if we rethought about things similar to how Einstein thought of relativity could that change our understanding of the universe and would that make it more easier to combine the standard model and GR?
Physicists have all kinds of thoughts and ideas that they mull over when trying to develop new theories or ways to merge old ones together. I assure you that anything you can think of has already been tried.
 
3,722
405
You may have the wrong idea about what theory of relativity is. Your example with temperatures does not have any relation to the purpose of the theory of relativity. It is not even an example of a "relative" quantity in the common sense of the therm.
 
29
0
Physicists have all kinds of thoughts and ideas that they mull over when trying to develop new theories or ways to merge old ones together. I assure you that anything you can think of has already been tried.
Im sure it has but in case it hasnt I like to ask my questions. Another thought i just had is that since nothing can be colder than absolute zero isnt that the same as nothing can be faster than the speed of light.
 

Drakkith

Staff Emeritus
Science Advisor
2018 Award
20,440
4,135
Another thought i just had is that since nothing can be colder than absolute zero isnt that the same as nothing can be faster than the speed of light.
No.
 

PeroK

Science Advisor
Homework Helper
Insights Author
Gold Member
2018 Award
9,095
3,279
If you bring the temperature to absolute zero atoms stop moving.

If you move at the speed of light time stops.

Seems similar to me.
It's an interesting idea. If an object moves relative to you, owing to time dilation the thermal motion of its atoms ought to decrease (relative to you). And, if it gets close to the speed of light relative to you, then it might look like its temperature is close to absolute zero.

There are some interesting things online about how to define and measure the temperature of an object that is moving relative to you. E.g.


You might also ask yourself. If you cool an object and that somehow equates to accelerating the object relative to you, what happens if you heat up an object?
 
29
0
It's an interesting idea. If an object moves relative to you, owing to time dilation the thermal motion of its atoms ought to decrease (relative to you). And, if it gets close to the speed of light relative to you, then it might look like its temperature is close to absolute zero.

There are some interesting things online about how to define and measure the temperature of an object that is moving relative to you. E.g.


You might also ask yourself. If you cool an object and that somehow equates to accelerating the object relative to you, what happens if you heat up an object?
That's a very interesting thought. It must slow down in relative terms.
You may have the wrong idea about what theory of relativity is. Your example with temperatures does not have any relation to the purpose of the theory of relativity. It is not even an example of a "relative" quantity in the common sense of the therm.
Temperature is definitely relative. hence the zeroth law of thermodynamics. If, in my example, A and B are in thermal equilibrium but B and C arent then C will feel a temperature difference, hence it would feel if A and B were hot or cold. ie. temperature is relative.
 
14,891
4,567
Temperature is definitely relative. hence the zeroth law of thermodynamics. If, in my example, A and B are in thermal equilibrium but B and C arent then C will feel a temperature difference, hence it would feel if A and B were hot or cold. ie. temperature is relative.
Yes, but that has absolutely nothing to do with Einstein's Theory of Relativity (either SR or GR).
 

ZapperZ

Staff Emeritus
Science Advisor
Education Advisor
Insights Author
2018 Award
34,792
3,689
That's a very interesting thought. It must slow down in relative terms.

Temperature is definitely relative. hence the zeroth law of thermodynamics. If, in my example, A and B are in thermal equilibrium but B and C arent then C will feel a temperature difference, hence it would feel if A and B were hot or cold. ie. temperature is relative.
You have a bit of a skewered idea on why a different line of thought appears in science, and in physics in particular.

If you look at Einstein and the history of physics, he came up with the idea of Special Relativity not because he was bored and decided "Hey, what if....?" out of nowhere. There was a very clear impetus for him coming up with the idea because of the problems of Maxwell equations not be covariant under Galilean transformation. In other words, there was a problem at that time, and he was trying to approach it from a different perspective. And then, when he came up with a new idea, he did one very important thing. He showed mathematically that this new idea converges with the old description.

Unfortunately, you never gave a clear impetus for why you'd want to think of temperature having the same "relative" concept. You simply can't invoke "Well, what if.... since we already have relativity...", without specifying what exactly is the problem that would be solved if we look at thermodynamics from the different perspective. In other words, what is the worth of our time to delve into this? What does it do? What does it solve? Can it clean windows in record time?

There are infinite number of ideas out there that one can explore. The question is, while it may be interesting, but is it important? Those two criteria are not necessarily mutually inclusive.

Zz.
 
29
0
That's a very interesting thought. It must slow down in relative terms.

Temperature is definitely relative. hence the zeroth law of thermodynamics. If, in my example, A and B are in thermal equilibrium but B and C arent then C will feel a temperature difference, hence it would feel if A and B were hot or cold. ie. temperature is relative.
You may have the wrong idea about what theory of relativity is. Your example with temperatures does not have any relation to the purpose of the theory of relativity. It is not even an example of a "relative" quantity in the common sense of the therm.
here is another thought that relates to GR, if I take a balloon filled with air, and lets assume this balloon cant pop or melt , and we heat it up from the outside. the balloon will change its geometry in spacetime. If we instead of heating the balloon we pump air in the balloon it will still expand its geometry in spacetime. No? the balloon doesnt know or care how the spacetime around it was affected only that it is now changed.

This idea is similar to Einsteins thought that triggered GR. A man in freefall doesnt feel his own weight.
 
29
0
You have a bit of a skewered idea on why a different line of thought appears in science, and in physics in particular.

If you look at Einstein and the history of physics, he came up with the idea of Special Relativity not because he was bored and decided "Hey, what if....?" out of nowhere. There was a very clear impetus for him coming up with the idea because of the problems of Maxwell equations not be covariant under Galilean transformation. In other words, there was a problem at that time, and he was trying to approach it from a different perspective. And then, when he came up with a new idea, he did one very important thing. He showed mathematically that this new idea converges with the old description.

Unfortunately, you never gave a clear impetus for why you'd want to think of temperature having the same "relative" concept. You simply can't invoke "Well, what if.... since we already have relativity...", without specifying what exactly is the problem that would be solved if we look at thermodynamics from the different perspective. In other words, what is the worth of our time to delve into this? What does it do? What does it solve? Can it clean windows in record time?

There are infinite number of ideas out there that one can explore. The question is, while it may be interesting, but is it important? Those two criteria are not necessarily mutually inclusive.

Zz.
That is true thank you for this.

I am hoping if i put my stupid ideas out to people who know more about the subject than me maybe it will spark some idea in them.

but also, my thoughts are within the realm of relating the standard model and GR. maybe if we rethink things in terms of GR maybe we can combine them in a previously unthought of way. for example according the GR objects of energy change the geometry of spacetime. atoms have energy, why isnt it that they are change the geometry of spacetime around it in a similar way the sun does?
 

PeroK

Science Advisor
Homework Helper
Insights Author
Gold Member
2018 Award
9,095
3,279
That's a very interesting thought. It must slow down in relative terms.

Temperature is definitely relative. hence the zeroth law of thermodynamics. If, in my example, A and B are in thermal equilibrium but B and C arent then C will feel a temperature difference, hence it would feel if A and B were hot or cold. ie. temperature is relative.
One problem with your idea is that light, which does travel at the speed of light, would be at absolute zero. So, the light from the Sun would cool us down. But, of course, sunlight not only keeps us warm, but ultimatley is the source of all energy on Earth.
 
29
0
One problem with your idea is that light, which does travel at the speed of light, would be at absolute zero. So, the light from the Sun would cool us down. But, of course, sunlight not only keeps us warm, but ultimatley is the source of all energy on Earth.
but thats because we dont move at the speed of light. so this change in momentum as the photon particles interact with us cause the appearance of a temperature increase
 

ZapperZ

Staff Emeritus
Science Advisor
Education Advisor
Insights Author
2018 Award
34,792
3,689
That is true thank you for this.

I am hoping if i put my stupid ideas out to people who know more about the subject than me maybe it will spark some idea in them.

but also, my thoughts are within the realm of relating the standard model and GR. maybe if we rethink things in terms of GR maybe we can combine them in a previously unthought of way. for example according the GR objects of energy change the geometry of spacetime. atoms have energy, why isnt it that they are change the geometry of spacetime around it in a similar way the sun does?
That still doesn't answer on WHY one would want to do such a thing.

Again, as I've said, it may be "interesting" (to you), but why is it important? What does it solve or make simpler or clearer?

This, you have not clarified.

Zz.
 
29
0
That still doesn't answer on WHY one would want to do such a thing.

Again, as I've said, it may be "interesting" (to you), but why is it important? What does it solve or make simpler or clearer?

This, you have not clarified.

Zz.
I will have to ponder on this. Thank you
 
29
0
One problem with your idea is that light, which does travel at the speed of light, would be at absolute zero. So, the light from the Sun would cool us down. But, of course, sunlight not only keeps us warm, but ultimatley is the source of all energy on Earth.
What I mean is not that light because it moves at the speed of light is cold, its that because light is moving at the speed of light everything around it seems cold. This temperature difference causes us to feel the heat of the light.

Imagine you are a light beam moving from the sun to the earth. your traveling at .9c, time would slow down, hence atoms and molecules around you would inturn slow down. when molecules slow down they become cold. Therefore if you were to slow down time and touch an object it would appear cold.
 

ZapperZ

Staff Emeritus
Science Advisor
Education Advisor
Insights Author
2018 Award
34,792
3,689
What I mean is not that light because it moves at the speed of light is cold, its that because light is moving at the speed of light everything around it seems cold. This temperature difference causes us to feel the heat of the light.

Imagine you are a light beam moving from the sun to the earth. your traveling at .9c, time would slow down, hence atoms and molecules around you would inturn slow down. when molecules slow down they become cold. Therefore if you were to slow down time and touch an object it would appear cold.
This is faulty physics that you invented. Light beam does not move at 0.9c. It has to be "c". It is not an arbitrary choice.

And if you think you can transform to light's frame of reference, I'd like you to point out to me what physics you are using to do that, because SR/GR does not allow such a transformation.

Zz.
 

PeroK

Science Advisor
Homework Helper
Insights Author
Gold Member
2018 Award
9,095
3,279
What I mean is not that light because it moves at the speed of light is cold, its that because light is moving at the speed of light everything around it seems cold. This temperature difference causes us to feel the heat of the light.

Imagine you are a light beam moving from the sun to the earth. your traveling at .9c, time would slow down, hence atoms and molecules around you would inturn slow down. when molecules slow down they become cold. Therefore if you were to slow down time and touch an object it would appear cold.
You started with an interesting idea and now you are having to reinvent physics and deny experimental facts to support it!

In any case, these forums are for discussing science, not your personal theories about how science ought to be.
 
29
0
You started with an interesting idea and now you are having to reinvent physics and deny experimental facts to support it!

In any case, these forums are for discussing science, not your personal theories about how science ought to be.
How do you mean? this isnt about what science ought to be. I havent reinvented anything. Just think logically. If you slow down time do atoms hold there heat relative to you? If you are standing next to a boiling pot of water and you somehow stopped time, if you touched the boiling water would it feel hot?
 
29
0
This is faulty physics that you invented. Light beam does not move at 0.9c. It has to be "c". It is not an arbitrary choice.

And if you think you can transform to light's frame of reference, I'd like you to point out to me what physics you are using to do that, because SR/GR does not allow such a transformation.

Zz.
wow dude. ok, so you are traveling at c and time stops. If you are standing next to a boiling pot of water if you touched the boiling water would it feel hot?
 

ZapperZ

Staff Emeritus
Science Advisor
Education Advisor
Insights Author
2018 Award
34,792
3,689
wow dude. ok, so you are traveling at c and time stops. If you are standing next to a boiling pot of water if you touched the boiling water would it feel hot?
But that is what I warned you about transforming to the light's reference frame! I told you to watch out for that big hole in the ground, and you still fell into it! (My students will get a chuckle out of that phrase.)

If you are moving at c, what physics did you use? You can't use the consequences predicted by SR, because in SR, the speed of light is ALWAYS "c" in any frame. So again, what physics did you use to be able to describe your world when you're moving at c?

Zz.
 

Physics Forums Values

We Value Quality
• Topics based on mainstream science
• Proper English grammar and spelling
We Value Civility
• Positive and compassionate attitudes
• Patience while debating
We Value Productivity
• Disciplined to remain on-topic
• Recognition of own weaknesses
• Solo and co-op problem solving

Hot Threads

Top