Josephson equations by Ciro Santilli 40 Updated 2025-07-16
Two equations derived from first principles by Brian Josephson that characterize the device, somewhat like an I-V curve:
where:
Note how these equations are not a typical I-V curve, as they are not an instantaneous dependency between voltage and current: the history of the voltage matters! Or in other words, the system has an internal state, represented by the Josephson phase at a given point in time.
To understand them better, it is important to look at some important cases separately:
Magnetic flux quantum by Ciro Santilli 40 Updated 2025-07-16
TODO is there any relationship between this and the Josephson effect?
This appears to happen to any superconducting loop, because the superconducting wave function has to be continuous.
Video "Superconducting Qubit by NTT SCL (2015)" suggests that anything in between gets cancelled out by a superposition of current in both directions.
Deuterium by Ciro Santilli 40 Updated 2025-07-16
Applications:
We can almost reach the Lie algebra of any isometry group in a single go. For every in the Lie algebra we must have:
because has to be in the isometry group by definition as shown at Section "Lie algebra of a matrix Lie group".
Then:
so we reach:
With this relation, we can easily determine the Lie algebra of common isometries:
Islam character by Ciro Santilli 40 Updated 2025-07-16
Islam has some really nice things in it.
The way it was perverted to be used as a tool for terrorism by some is a great tragedy.
Ciro Santilli especially appreciates the ideas of
ARPANET by Ciro Santilli 40 Updated 2025-07-16
Bibliography:

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