Seasons
This is a forum or general chit-chat, small talk, a "hey, how ya doing?" and such. Or hell, get crazy deep on something. Whatever you like.
Posts 3,966 - 3,977 of 6,170
Are we embarrassing you with all this girl talk? We may be talking about waves, but at least we're not discussing periods!
embarassed? Not in the least. I have been married for long enough that there is very little that could embarass, surprise or mystify me about the female psyche or biology.
Except perhaps, there is one thing that I have never understood - why are there always at least 4 combs, 2 hairbrushes and an acre of disposable tissues in an average handbag? And what on earth accounts for the other several kilos of "stuff"?
I've gone camping with less gear than my wife regards as essential for the shortest of trips beyond the front door!
The electromagnetic wave is a different wave entirely
Well, this is what I keep agreeing with you about. My point about numbers in [0,1] versus complex numbers is something else. I thought that you were aguing like this:
(a) In order to interfere subtractively, waves have to be able to take on negative values. But probabilities are never negative, they are all numbers between 0 and 1, inclusive. Therefore, if Psi were a probability, it couldn't interfere.
This also seems to be the drift of Penrose's argument, "In the first place, ... in the two-slit experiment." Indeed, I agree with everything Penrose says there.
Now, I agree with (a), both the reasoning and the conclusion. I agreed with the Penrose critique of the phrase "probability wave" the first time you mentioned it, with the minor reservation that it has become so common to call it the "Probability wave" that many people do so even though they know that it is technically incorrect.
OK, so he has proved that a common idiom is actually conceptually sloppy if taken literally. That is a critique of language, not of physical theory. Because I agree, however, I have tried to always say "Psi", not "the probability wave," or even "the probability amplitude wave." And I think I have been fairly successful, so I remain puzzled at your repeating this point.
Psi does, however, "give" (to use your word) the probabilities, in that, given Psi, one can calculate the probabilities from it. The method of calculation of Psi is such that even though Psi itself generally has complex values, the calculated probabilities end up in [0,1], as they should. This is what is assured by normalization and complex conjugation, and that is why I found it relevant to mention them.
embarassed? Not in the least. I have been married for long enough that there is very little that could embarass, surprise or mystify me about the female psyche or biology.
Really? I've had a few relationships in my time, (not a large sample perhaps, but long-term qualitative studies that have fostered some familiarity with the male gender) and I must admit there are times given male behaviors will still surprise and yes, even embarrass me (though sometimes the surprises may be pleasant too). Women must be easier to understand than men are. All this time men I know have said that women are crazy, it was just part of your gender's projections of your own complex illogical testosterone-colored world.
Except perhaps, there is one thing that I have never understood - why are there always at least 4 combs, 2 hairbrushes and an acre of disposable tissues in an average handbag? And what on earth accounts for the other several kilos of "stuff"?
People expect us to have all that crap. I try not to carry a purse, but you have to put your wallet somewhere, and the cell phone, and keys...etc. Most of my clothes simply don't have good pockets for all that and even those with pockets would have odd bulges if I actually put stuff in the pockets (not that everything I own is skin-tight but women's clothes are cut differently than men's clothes). If I could con the man I am with into carrying everything I would never have a purse.
My father, who is admittedly in his 80s and not like "modern" men, carries a hanky, wallet, keys, cough drops, nail clippers, plastic comb and eyeglasses in various pockets. Men's pants and jackets seem built for that. Maybe I should just wear men's clothes.
I've gone camping with less gear than my wife regards as essential for the shortest of trips beyond the front door!
Camping must be easy in Scotland. I need a tent, sleeping bag, swiss army knife, basic foods and other items when I venture out. Yes, I also make room in the pack for chocolate. Ruffing it is no reason to be uncivilized.
Camping must be easy in Scotland. I need a tent, sleeping bag, swiss army knife, basic foods and other items when I venture out. Yes, I also make room in the pack for chocolate. Ruffing it is no reason to be uncivilized.
Well, I'm in Wales, but all I'd pack extra for Scotland would be midge repellant. Yes - tent, sleeping bag, folding bed, selection of tools, fishing gear, plenty of food, a selection of beverages, stove, a few extra cans of fuel, pots and pan, laptop, solar panels... still less than my wife can cram in her handbag
Actually I work on the principle that if it won't fit in my pockets, I'm not taking it.
No one forces women to wear impractical clothes with no pockets, and who actually needs 6 lipsticks (including 2 empty ones,) a bottle of mineral water, half a stale flapjack and 2 mirrors just to go and post a letter anyway?
The few male friends I have who have bought into the whole "man bag" thing, still manage to cope with a dainty little bag on a strap, like a camera case. Not a great belt-handled, leather tardis.
Posts 3,966 - 3,977 of 6,170
psimagus
18 years ago
18 years ago
embarassed? Not in the least. I have been married for long enough that there is very little that could embarass, surprise or mystify me about the female psyche or biology.
Except perhaps, there is one thing that I have never understood - why are there always at least 4 combs, 2 hairbrushes and an acre of disposable tissues in an average handbag? And what on earth accounts for the other several kilos of "stuff"?
I've gone camping with less gear than my wife regards as essential for the shortest of trips beyond the front door!
Irina
18 years ago
18 years ago
Dear Bev (3963):
I was referring, of course, to an apparatus that generates vibrations, i.e., waves, for the purpose of displaying diffraction, interference, and other wave phenomena, to aid in our discussion of Quantum Mechanics. What did you think I meant?
(3964) Isn't it "minimis"? Ablative plural?
I was referring, of course, to an apparatus that generates vibrations, i.e., waves, for the purpose of displaying diffraction, interference, and other wave phenomena, to aid in our discussion of Quantum Mechanics. What did you think I meant?
(3964) Isn't it "minimis"? Ablative plural?
Irina
18 years ago
18 years ago
(a) In order to interfere subtractively, waves have to be able to take on negative values. But probabilities are never negative, they are all numbers between 0 and 1, inclusive. Therefore, if Psi were a probability, it couldn't interfere.
This also seems to be the drift of Penrose's argument, "In the first place, ... in the two-slit experiment." Indeed, I agree with everything Penrose says there.
Now, I agree with (a), both the reasoning and the conclusion. I agreed with the Penrose critique of the phrase "probability wave" the first time you mentioned it, with the minor reservation that it has become so common to call it the "Probability wave" that many people do so even though they know that it is technically incorrect.
OK, so he has proved that a common idiom is actually conceptually sloppy if taken literally. That is a critique of language, not of physical theory. Because I agree, however, I have tried to always say "Psi", not "the probability wave," or even "the probability amplitude wave." And I think I have been fairly successful, so I remain puzzled at your repeating this point.
Psi does, however, "give" (to use your word) the probabilities, in that, given Psi, one can calculate the probabilities from it. The method of calculation of Psi is such that even though Psi itself generally has complex values, the calculated probabilities end up in [0,1], as they should. This is what is assured by normalization and complex conjugation, and that is why I found it relevant to mention them.
Irina
18 years ago
18 years ago
Psimagus:
As to the electrogravity.com requote, I remain puzzled as to why, after apparently quoting the abovementioned Penrose argument with approval, you then proceed to quote (also with apparent approval) a passage in which the term "probability wave" is used for Psi.
And I remain utterly mystified by your claim that I "clearly disagree." I agree that Psi in Quantum Mechanics is not the same as the electromagnetic wave in Classical Physics, and I have said this many times. Quantum Mechanics claims to supercede Classical Electromagnetic Theory, not to reformulate it.
As to the electrogravity.com requote, I remain puzzled as to why, after apparently quoting the abovementioned Penrose argument with approval, you then proceed to quote (also with apparent approval) a passage in which the term "probability wave" is used for Psi.
And I remain utterly mystified by your claim that I "clearly disagree." I agree that Psi in Quantum Mechanics is not the same as the electromagnetic wave in Classical Physics, and I have said this many times. Quantum Mechanics claims to supercede Classical Electromagnetic Theory, not to reformulate it.
Irina
18 years ago
18 years ago
Since Psi itself is not a probability, it can take on negative values. Hence, there is no problem with Psi diffracting, or interfering with itself; or at least, not the problem suggested by argument (a) in message 3968.
In predicting what will appear on the screen in the two-slit experiment, we first find out what happens to Psi: Psi propagates from the source, passes through the slits, diffracts, interferes with itself, and arrives at the screen. Although Psi itself oscillates, the modulus (a.k.a. amplitude) of Psi has a fixed value at each point on the screen, just as a sound may have a fixed loudness at some point, even though it is a wave phenomenon. The probability that a scintillum will appear in a region is greater in those regions in which the average value of Psi is greater. I.e., the 'louder' Psi is, the more likely it is for there to be a scintillum.
In predicting what will appear on the screen in the two-slit experiment, we first find out what happens to Psi: Psi propagates from the source, passes through the slits, diffracts, interferes with itself, and arrives at the screen. Although Psi itself oscillates, the modulus (a.k.a. amplitude) of Psi has a fixed value at each point on the screen, just as a sound may have a fixed loudness at some point, even though it is a wave phenomenon. The probability that a scintillum will appear in a region is greater in those regions in which the average value of Psi is greater. I.e., the 'louder' Psi is, the more likely it is for there to be a scintillum.
Bev
18 years ago
18 years ago
Wow Schroedinger's chocolate bunny ate my last post! Good thing I looked in the toaster. Look what popped up.
(3964) Isn't it "minimis"? Ablative plural?
Yes. I make typos in all languages. I don't pay attention to correct forms of word in Latin any more than I do in English. This surprises you? :-)
If Psimagus is correct about my crossed-wires forming anagrams in a language no one knows yet, than minimus is correct, but the message is entirely different than the one I intended. I fear the world is not yet ready for that true message however. Scoff if you will, those of us with strange mutant neurological issues hold the key to survival of this species.
Yes. I make typos in all languages. I don't pay attention to correct forms of word in Latin any more than I do in English. This surprises you? :-)
If Psimagus is correct about my crossed-wires forming anagrams in a language no one knows yet, than minimus is correct, but the message is entirely different than the one I intended. I fear the world is not yet ready for that true message however. Scoff if you will, those of us with strange mutant neurological issues hold the key to survival of this species.
Bev
18 years ago
18 years ago
Really? I've had a few relationships in my time, (not a large sample perhaps, but long-term qualitative studies that have fostered some familiarity with the male gender) and I must admit there are times given male behaviors will still surprise and yes, even embarrass me (though sometimes the surprises may be pleasant too). Women must be easier to understand than men are. All this time men I know have said that women are crazy, it was just part of your gender's projections of your own complex illogical testosterone-colored world.
People expect us to have all that crap. I try not to carry a purse, but you have to put your wallet somewhere, and the cell phone, and keys...etc. Most of my clothes simply don't have good pockets for all that and even those with pockets would have odd bulges if I actually put stuff in the pockets (not that everything I own is skin-tight but women's clothes are cut differently than men's clothes). If I could con the man I am with into carrying everything I would never have a purse.
My father, who is admittedly in his 80s and not like "modern" men, carries a hanky, wallet, keys, cough drops, nail clippers, plastic comb and eyeglasses in various pockets. Men's pants and jackets seem built for that. Maybe I should just wear men's clothes.
I've gone camping with less gear than my wife regards as essential for the shortest of trips beyond the front door!
Camping must be easy in Scotland. I need a tent, sleeping bag, swiss army knife, basic foods and other items when I venture out. Yes, I also make room in the pack for chocolate. Ruffing it is no reason to be uncivilized.
Irina
18 years ago
18 years ago
Bev (3972):
Oh, Dear, Bev, I'm sorry! I had some vague idea at the time that it would be funny, but if I had a reason for thinking that, it has flown the coop now! Of course, you are entiled to typos, yust liek hte rets uv uts! Sometimes my insanity outruns my coping mechanisms. [Psi]
Oh, Dear, Bev, I'm sorry! I had some vague idea at the time that it would be funny, but if I had a reason for thinking that, it has flown the coop now! Of course, you are entiled to typos, yust liek hte rets uv uts! Sometimes my insanity outruns my coping mechanisms. [Psi]
psimagus
18 years ago
18 years ago
Irina,
As to the electrogravity.com requote, I remain puzzled as to why, after apparently quoting the abovementioned Penrose argument with approval, you then proceed to quote (also with apparent approval) a passage in which the term "probability wave" is used for Psi.
Because the terminology is not, in itself, very important. Our understanding of what it describes is what's important. Much as I have a natural sympathy for Penrose's pedantry, I am realist enough to know when a cause is lost. "probability wave" has been common parlance for too many decades to hope to change it now without causing a great deal more confusion than we clear away.
And I remain utterly mystified by your claim that I "clearly disagree."
Well, mainly statements along the line of "My view is that it's the wave, psi, which propagates" [#3807, your emphasis.] But perhaps I'm misinterpreting that when I understand it to mean that you claim psi propagates (my objection is not to the common parlance description of it as a "wave", merely to the nature of the thing. Psi is continuous, and does not propagate.)
I agree that Psi in Quantum Mechanics is not the same as the electromagnetic wave in Classical Physics, and I have said this many times. Quantum Mechanics claims to supercede Classical Electromagnetic Theory, not to reformulate it.
Very well, if we're agreed that it's the electromagnetic wave, not the probability wave, that propagates
Could you remind me of your view of quantum tunnelling? (I've lost track amid all these posts, I'm afraid.)
Because the terminology is not, in itself, very important. Our understanding of what it describes is what's important. Much as I have a natural sympathy for Penrose's pedantry, I am realist enough to know when a cause is lost. "probability wave" has been common parlance for too many decades to hope to change it now without causing a great deal more confusion than we clear away.
Well, mainly statements along the line of "
Very well, if we're agreed that it's the electromagnetic wave, not the probability wave, that propagates

Could you remind me of your view of quantum tunnelling? (I've lost track amid all these posts, I'm afraid.)
Bev
18 years ago
18 years ago
Irina, I was kidding! There are times when I have been sensitive about the dyslexia, but usually that's just when you hit me a the wrong time. Also, in that case, I was too lazy to look up "de minimis non curate lex" instead of just typing (and Firefox hasn't got much Latin in the spell check).
Women. No sense of humor.
Women. No sense of humor.

psimagus
18 years ago
18 years ago
Well, I'm in Wales, but all I'd pack extra for Scotland would be midge repellant. Yes - tent, sleeping bag, folding bed, selection of tools, fishing gear, plenty of food, a selection of beverages, stove, a few extra cans of fuel, pots and pan, laptop, solar panels... still less than my wife can cram in her handbag

Actually I work on the principle that if it won't fit in my pockets, I'm not taking it.
No one forces women to wear impractical clothes with no pockets, and who actually needs 6 lipsticks (including 2 empty ones,) a bottle of mineral water, half a stale flapjack and 2 mirrors just to go and post a letter anyway?
The few male friends I have who have bought into the whole "man bag" thing, still manage to cope with a dainty little bag on a strap, like a camera case. Not a great belt-handled, leather tardis.
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