Questions tagged [terminology]
Use this for questions relating to the proper use of physics terminology or nomenclature.
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Should it be obvious that independent quantum states are composed by taking the tensor product?
My text introduces multi-quibt quantum states with the example of a state that can be "factored" into two (non-entangled) substates. It then goes on to suggest that it should be obvious1 ...
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Are matrices and second rank tensors the same thing?
Tensors are mathematical objects that are needed in physics to define certain quantities. I have a couple of questions regarding them that need to be clarified:
Are matrices and second rank tensors ...
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What is the difference between electric potential, electrostatic potential, potential difference (PD), voltage and electromotive force (EMF)?
This is a confused part ever since I started learning electricity. What is the difference between electric potential, electrostatic potential, potential difference (PD), voltage and electromotive ...
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What does "the ${\bf N}$ of a group" mean?
In the context of group theory (in my case, applications to physics), I frequently come across the phrase "the ${\bf N}$ of a group", for example "a ${\bf 24}$ of $\mathrm{SU}(5)$" or "the ${\bf 1}$ ...
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Is Pauli-repulsion a "force" that is completely separate from the 4 fundamental forces?
You can have two electrons that experience each other's force by the exchange of photons (i.e. the electromagnetic force). Yet if you compress them really strongly, the electromagnetic interaction ...
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What sets a "Law" apart from a "Rule" or a "Principle"? [duplicate]
Basically, I understand the difference between a "Theory" and a "Theorem" but I am quite confused when it comes to "Law", "Rule" and "Principle". Can you make the differences clear to me?
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Gibbs free energy intuition
What is Gibbs free energy? As my book explains:
Gibbs energy is the energy of a system available for work.
So, what does it want to tell? Why is it free? Energy means ability to do work. What is ...
user36790
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Is the Big Bang defined as before or after Inflation?
Is the Big Bang defined as before or after Inflation? Seems like a simple enough question to answer right? And if just yesterday I were to encounter this, I'd have given a definite answer. But I've ...
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What is "pure energy" in matter-antimatter annihilation made of?
I used to read the term "pure energy" in the context of matter-antimatter annihilation. Is the "pure energy" spoken of photons? Is it some form of heat? Some kind of particles with mass?
Basically,...
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In layman's terms, what is a quantum fluctuation?
What causes it and how does it occur? If you do post some mathematics, please explain what each term means too please.
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Nomenclature: Yang-Mills theory vs Gauge theory
If you're writing about a theory with Yang-Mills/Gauge fields for an arbitrary reductive gauge group coupled to arbitrary matter fields in some representation,
is it best to call it a Yang-Mills ...
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Is the Lagrangian of a quantum field really a 'functional'?
Weinberg says, page 299, The quantum theory of fields, Vol 1, that
The Lagrangian is, in general, a functional $L[\Psi(t),\dot{\Psi}(t)$], of a set of generic fields $\Psi[x,t]$ and their time ...
Jason
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What does Enthalpy mean?
What is meant by enthalpy? My professor tells me "heat content". That literally makes no sense. Heat content, to me, means internal energy. But clearly, that is not what enthalpy is, considering: $H=U+...
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Difference between 1PI effective action and Wilsonian effective action?
What is the simplest way to describe the difference between these two concepts, that often go by the same name?
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Is the term "quantum fluctuation" an aide to understanding? [closed]
I would like to ask if anyone has found a tight enough way to define the term "quantum fluctuation" so that it can become a useful rather than a misleading piece of physics terminology.
Terminology ...
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