Why are tubes called "valves" but transistors aren't?

As I understand it, tubes and transistors do the same job, tubes are just more complicated. I understand why one might call a tube a "valve", but then isn't the term equally applicable to a transistor? Yet I see valve used to uniquely describe a vacuum tube. Is it just history and tradition?
 
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Bipolar transistors are more complicated than a tube, using quantum mechanics and all that.
Tubes are ballistic devices.

The earliest experimental vacuum tubes were literally built inside glass tubes, hence the name.
"Valve" is just a colloquialism the English use, like "torch" for flashlight.
In power electronics, more recently, we term transistors as "switches".
 
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"The worst part is, I can’t tell if that’s gibberish or real math."
Quantum potential in a crystal lattice.

At the frontier, the distinction fades. Some math proofs are now hundreds of pages long.
Even the researcher's office mate may not be able to make sense of their paper.
 
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Ok, you guys are right about physics! I was thinking of the multiple voltage requirements and such for running a tube vs the simple three pins of a transistor.

The physics of the tube are rather classical electro-magnetism.

The physics of the a transistor take into account atomic physics.... and don't forget that 0.6V drop.

Besides, it's more fun to work with a 440V power supply than 36V!
 
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The worst part is, I can’t tell if that’s gibberish or real math 😅

it should be obvious

(1) The left term should be a function of (r)
(2) The right term uses (r) correctly only half way and he used 'unk(r)' which in reality should be zap(r)

Try this:

1693961540004.png


https://www.electronics-tutorials.ws/diode/diode_2.html
 
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We called them tubes here, because they were standard off the shelf glass tubes, adapted for the purpose.
The name was literal, not informal, since there was no other name for them at the time (or even now).

A 1920 De Forest transmitting tube.
 

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