Hysteresis
Hysteresis is the name of a phenomenon in electrical systems in which the state of a system depends on the history of how it arrived at its current state. Hysteresis is most commonly observed in magnetism (and hence in AC transformer circuits), but it can arise in many other contexts, both in electrical circuits and in any system which can be said to have memory.
The word, hysteresis, comes from a Greek root that variously means deficiency, shortcoming, or falling behind. The etymology of hysteresis is not related to the similar sounding word, hysteria, which comes from the Latin word for womb (or uterus).
One of the most interesting explanations of hysteresis comes from a model of the Bose-Einstein Condensate, in which a tiny perturbation in some arbitrary direction seeds a macroscopic departure in that direction. Imagine something delicately balanced on the razor's edge. Then the tiniest perturbation in one direction or another will determine which way the balanced object falls.
Once a system subject to hysteresis has arrived at a given state, it can take a substantial amount of energy to bring it to a different state.
There is a related model of how hysteresis works in neural networks to form persistent memories and beliefs that, once formed, become immune to revision, even when the evidence for revising a belief is considerably stronger than the original evidence for forming a belief in the first place. When that happens, a paradigm shift cannot take place until the evidence for revising a memorized state exceeds some fairly large threshold called the tipping point.
Oddly enough, when the tipping point is reached and a sudden paradigm shift occurs, the phenomenon is reminiscent of hysteria, which Freud and others of his age imagined to be a sudden disturbance of the womb.
Isn't that hysterical?
The word, hysteresis, comes from a Greek root that variously means deficiency, shortcoming, or falling behind. The etymology of hysteresis is not related to the similar sounding word, hysteria, which comes from the Latin word for womb (or uterus).
One of the most interesting explanations of hysteresis comes from a model of the Bose-Einstein Condensate, in which a tiny perturbation in some arbitrary direction seeds a macroscopic departure in that direction. Imagine something delicately balanced on the razor's edge. Then the tiniest perturbation in one direction or another will determine which way the balanced object falls.
Once a system subject to hysteresis has arrived at a given state, it can take a substantial amount of energy to bring it to a different state.
There is a related model of how hysteresis works in neural networks to form persistent memories and beliefs that, once formed, become immune to revision, even when the evidence for revising a belief is considerably stronger than the original evidence for forming a belief in the first place. When that happens, a paradigm shift cannot take place until the evidence for revising a memorized state exceeds some fairly large threshold called the tipping point.
Oddly enough, when the tipping point is reached and a sudden paradigm shift occurs, the phenomenon is reminiscent of hysteria, which Freud and others of his age imagined to be a sudden disturbance of the womb.
Isn't that hysterical?
posted by Moulton | 12:55 PM
8 Comments:
Good luck with your hysteresis. Will it require emesis?
Was it something you ate?
I don't eat all the baloney some people try to feed me, and you shouldn't either.
Barry, I do think it was the baloney. You may have eaten it years ago, but you are now suffering indigestion from it. Yes, you might need to vomit it out. Sorry. I wish I could suggest a better way.
I'd hoped you could digest it, and derive some value from the process. Apparently not.
Interesting that you point to a Shermer video. Would you explain what you intended by that?
I intended to dash your hopes regarding the nutritional value of baloney.
Barry, you aren't well. You've lost both your compass and your sense of humor.
Now what about that Shermer video? Do you imagine that I'll watch some random youtube video, taking up all that time, without some sense of why I might be interested?
Abd, you have the God-given right to remain as ignorant and as oblivious as you like, and there is absolutely nothing I can do about it.
Your learning curve is not in my hands.
What you have generously given is returned to you redundantly.
Mazel tov.
In any case, I did watch the video and transcribed the section on cold fusion, which conclusively shows that Shermer had his head wedged in a place from which couldn't see what was in front of him, behind him, nor even to the sides.
He actually states that nobody could confirm Fleischmann's results. Now, you can argue that the work in the field is shoddy, you can argue this and that -- fraudulently, but set that aside -- but .... there are 153 independent peer-reviewed mainstream journal reports of excess heat in palladium deuteride, all from people trying to confirm Fleischmann's work.
There are a handful of negative replications, which, given what the positive reports say -- this effect is chaotic, difficult to control, etc., -- do not negate the positive confirmations at all.
If Shermer is not purely ignorant, he lied. I have no idea why he'd lie about this, it impeaches the rest of his work, so I assume ignorance.
But he read Goodstein, presumably. So, again, his ignorance is totally puzzling. Goodstein, among other things, talks about replication.
Try reading some of Goodstein, you can search the text on Amazon looking for "convince themselves that they are in the possession of knowledge that does not in fact exist." See the pages just before, where he talks about replication of excess heat by Scaramuzzi and what he thinks about the work.
Of course, Shermer wrote that review in Scientific American this year, and did the video last year, so maybe.... but he still misrepresented Goodstein, badly, in his review. Surely you can see this, it does not depend on whether cold fusion is real or not.
Go and sin no more.
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