Temperature and level temperatures

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In summary, the conversation discusses the Fermi temperature and its interpretation, with some participants doubting its significance. The formula 1/T = dS/dE is explored, and it is suggested that a temperature can be assigned to each energy level and contribute to the overall temperature. The use of this formula for calculations is debated, but the concept is open for discussion.
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ShayanJ
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I remember a day in the last year thinking about Fermi temperature([itex] T_f=k \varepsilon_f [/itex]) and its interpretation.People were saying its just a notation and has no meaning but I doubted that.So I did some calculations and had some interpretations.Then I forgot it until recently that I remembered it again.Now I want to know others' ideas about it.I know maybe some of you say personal theories aren't allowed here but I don't think its that big to be called a personal theory.

Consider the formula [itex] \frac{1}{T}=\frac{\partial S}{\partial E} [/itex] which can also be written in the form [itex] \frac{1}{T}=\sum \frac{\partial S}{\partial N_i}\frac{\partial N_i}{\partial E} [/itex].
Taking into account [itex] E=\sum N_i \varepsilon_i[/itex] we can write for a constant volume system [itex] dE=\sum \varepsilon_i dN_i [/itex] and assuming [itex] \frac{\partial x}{\partial y}=\frac{1}{\frac{\partial y}{\partial x}} [/itex],we have [itex] \frac{\partial N_i}{\partial E}=\frac{1}{\varepsilon_i} [/itex].
Now considering the Boltzmann statistics,we have [itex] \frac{\partial S}{\partial N_i}=k\ln{\frac{g_i}{N_i}} [/itex] so at last we have [itex] \frac{1}{T}=\sum \frac{1}{T_i}\ln{\frac{g_i}{N_i}} [/itex] where [itex] T_i=\frac{\varepsilon_i}{k} [/itex].
There can be similar formulas for the other two statistics.
I know it can't be used for true calculations but I think an interpretation of it is that we can assign a temperature to each energy level and then each of these "level temperatures" contribute to the real temperature by a factor which is determined by the properties of that level and also the statistics we're assigning to the particles.
Any idea is welcome.
 
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@ShayanJ have you come to more understanding on this?
 

Related to Temperature and level temperatures

1. What is temperature?

Temperature is a measure of the average kinetic energy of the particles in a substance. It is commonly measured in degrees Celsius (°C) or degrees Fahrenheit (°F).

2. What is the difference between temperature and heat?

Temperature and heat are related but different concepts. Temperature is a measure of the average kinetic energy of particles, while heat is the total amount of energy in a substance. Temperature does not depend on the size or amount of the substance, while heat does.

3. How is temperature measured?

Temperature is typically measured using a thermometer. The most common type of thermometer is a liquid-filled thermometer that uses mercury or alcohol to expand and contract in response to temperature changes.

4. What is absolute zero?

Absolute zero is the theoretical lowest possible temperature that can be reached, at which all molecular motion would cease. It is defined as 0 Kelvin (K), which is equivalent to -273.15 degrees Celsius (°C) or -459.67 degrees Fahrenheit (°F).

5. Why do we use different temperature scales?

Different temperature scales were created by different scientists at different times for different purposes. For example, the Fahrenheit scale was created by Gabriel Fahrenheit in 1724 and was originally based on the freezing point of brine. The Celsius scale, created by Anders Celsius in 1742, is based on the freezing and boiling points of water. The Kelvin scale was created by William Thomson in 1848 and is based on absolute zero. Different scales are used for different applications and are often converted to other scales for convenience.

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