Wikipedia:Reference desk/Archives/Science/2021 October 19

= October 19 =

What's the cause of short circuit in this circuit?
In electrical devices, unintentional short circuits are usually caused another conducting material is introduced, allowing charge to flow along a different path than the one intended.

If another conductor is introduced then it makes circuit series connection, then what causes short circuit? Rizosome (talk) 01:24, 19 October 2021 (UTC)
 * Who says it does? What circuit are you talking about? There's an infinite number of combinations. Give us something to work with. --OuroborosCobra (talk) 02:05, 19 October 2021 (UTC)
 * Ummm... the conductor you introduced? The conductor has a (relatively) low resistance so the current will bypass the intended path of the current - essentially taking a shortcut i.e. the "short" circuit. 41.165.67.114 (talk) 05:58, 19 October 2021 (UTC)

It says here Rizosome (talk) 02:29, 19 October 2021 (UTC)
 * That section does not mention a " series connection". The cause of a short circuit is always the appearance of a new low-resistance parallel connection in the circuit. --Lambiam 07:49, 19 October 2021 (UTC)

Particle creation
In subatomic reactions which involve creation of particles, e.g. when stuff is smashed together at very high energies, is it known or believed whether the creation of these particles is truly instantaneous, or whether there is a finite (presumably incredibly short) formation period? — Preceding unsigned comment added by 2A00:23C8:7B08:6A00:F0CC:7064:9880:EDB7 (talk) 10:38, 19 October 2021 (UTC)
 * Such a thing may be unknowable. According to the uncertainty principle, certain measurable properties, known as Conjugate variables, cannot be simultaneously known to the same level of certainty.  One of those conjugate pairs is "The energy of a particle at a certain event" and the " time of the event" that produced that particle are such a conjugate pair.  If we know with high levels of certainty, the amount of energy of said particles, what we cannot know to any real certainty is when the event occured.  It's not a technological limitation, it's baked into the mathematics of quantum physics.  -- Jayron 32 17:13, 19 October 2021 (UTC)


 * Leibniz asserted that "no transition is made through a leap", and I suspect most physicists, including quantum physicists, also hold this to be true. The idea of truly instantaneous change involving some spatial extension is fundamentally at odds with the theory of relativity. And, inasmuch as particles are excitations of some field, they have spatial extension. --Lambiam 18:53, 19 October 2021 (UTC)