Heat flow components of Stress/Energy Tensor

Thread starter TerryW
Start date Oct 27, 2023
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Heat flow Physics

Oct 27, 2023

TerryW

Gold Member

Homework Statement: Show that the Trace of the Heat Flux Stress/Energy Tensor is zero

Relevant Equations: T(heat) = q^i u^j + u^i q^j

I'm pretty sure I understand why q^i u^j + u^i q^i is the stress component (i \neq j) of the Heat Flux Stress/Energy Tensor but I can't think of, or find any explanation for why q^i u^i + u^i q^i = 0.

I found one reference in Lightman, Press, Price and Teukolsky - Problem Book in Relativity and Gravitation which just says
"Since q^α u_α = 0 (heat flux is spacelike in comoving frame)" but what does that really mean from a physics point of view?

Can anyone help?TerryW

PS - Preview doesn't seem to be working at the moment

Last edited: Oct 29, 2023

What are the heat flow components of Stress/Energy Tensor?

The heat flow components of Stress/Energy Tensor represent the flow of energy due to heat conduction in a material. These components describe how heat is transferred within the material under stress.

How do the heat flow components affect the overall stress/energy balance?

The heat flow components play a crucial role in the overall stress/energy balance of a material. They contribute to the total energy of the system and affect the distribution of stress within the material.

What is the significance of studying the heat flow components of Stress/Energy Tensor?

Studying the heat flow components of Stress/Energy Tensor is important for understanding the thermal behavior of materials under stress. This knowledge can help in predicting the response of materials to different thermal and mechanical conditions.

How are the heat flow components calculated in a material?

The heat flow components of Stress/Energy Tensor can be calculated using mathematical models that take into account the material's thermal conductivity, temperature gradient, and stress distribution. These calculations help in determining the heat transfer within the material.

Can the heat flow components of Stress/Energy Tensor be experimentally measured?

Yes, the heat flow components of Stress/Energy Tensor can be experimentally measured using techniques such as thermal imaging, heat flux sensors, and thermocouples. These measurements provide valuable data for validating theoretical models and understanding the thermal behavior of materials.