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bio website sjbyrnes.com
location Massachusetts
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visits member for 4 years, 1 month
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Jul
9
comment Fermi level alignment and electrochemical potential between two metals
Yes, $E_f$ in that figure is always fermi level aka electrochemical potential. Yes, it's safe to assume that the chemical potential in a metal is constant no matter what you do to the metal. (A semiconductor is different - you can change the chemical potential of a semiconductor using a gate or junction.)
Jul
8
answered Fermi level alignment and electrochemical potential between two metals
Jul
7
revised Chemical reaction as state transition?
added 7 characters in body
Jul
6
answered Chemical reaction as state transition?
Jul
6
comment Ideal gas concentration under temperature gradient
@joshphysics - Nice answer! I agree, pressure is constant, chemical potential is not. When temperature is not constant, chemical potential can vary in diffusive equilibrium. The Seebeck effect is the most famous example of this: For a wire with a temperature gradient, you can have a voltage across the wire with no current. In other words, you can have an electron (electro)chemical potential gradient without electron flow.
Jul
4
comment How to delay visible light
I agree with using mirrors. A more practical system is to use just two ordinary planar mirrors, that are parallel (or almost-parallel) to each other. The light can bounce back and forth 10 times no problem, and it's easy to align and set up.
Jun
27
comment Clarification on the Seebeck Effect
@John - I agree with Johannes. Just to be really really clear: If you have a devices-in-parallel configuration, the voltage does not change; if you have a devices-in-series configuration the voltage does change.
Jun
26
answered Could the chemical potential of a Bose gas be zero?
Jun
21
answered Why are there two quasi Fermi levels and only one Equilibrium Fermi level?
Jun
13
comment Why do metal objects in microwaves spark?
Are you quite sure? I would have guessed that the electric field part of the microwave, not the magnetic field part, would cause the spark...
Jun
3
answered Born rule for photons: it works, but it shouldn't?
Jun
2
awarded  Yearling
May
26
awarded  Revival
May
11
comment Donors/Acceptors in Metal Oxides
Is it a well-known fact that Cr is substituting Ti? (Not substituting O, not interstitial, not defect complex, not a combination of the above?)
May
3
comment Relativistic origin of magnetic field
@ChrisWhite - No one is disputing that "Electromagnetism in its entirety can be derived from Coulomb's Law plus SR, full stop." But there's a difference between "X can be derived from Y" and "Y is a fundamental principle and X is its less-fundamental consequence". For example, you can "derive" Newton's law of gravity from Kepler's laws, even though the former is actually more fundamental. These so-called "derivations" are useful and healthy pedagogical exercises, sure, but sometimes they mislead people about the big-picture fundamental relationships between different physical laws.
May
3
comment Microscopic picture of an inductor
Current creates a magnetic field because current is moving charge, and moving charge creates a magnetic field. Are you asking: "Why does moving charge create a magnetic field?"
May
3
answered Microscopic picture of an inductor
Apr
29
answered How does a force on electrons produce a force on a metal plate
Apr
26
comment What is the reasoning behind hole carriers being able to carry heat?
I wrote a more detailed explanation of what holes are at physics.stackexchange.com/questions/10800/… - that may help answer your question.
Apr
26
answered Is light red shifted in optical tweezers?