Questions re Cramer's Transactional Interpretation?

[Fredrik]

FrameDragger, if you're trying to convince her to come back, you're doing it really badly.

Rkastner, I don't think there was any unfriendly stuff in this thread until after you started saying that there was. When you started this thread, you said that the article you're working on will "address questions, confusions, or concerns about TI". We certainly don't need to study the original article to have questions or concerns (or confusions, ) about the TI, so I don't see how the type of responses you got could surprise you or offend you.

 

[conway]

But the processes of absorption and emition cannot be described by the Schrodinger equation (or a couple of Schrodinger equations). Right?
So either
1) TI replaces Schrodinger equation(s) by a different (set of) equation(s), or
2) TI does not provide a mathematical description of absorption and emition

Now please tell me which is correct: 1) or 2)?

I know there is a problem with describing absorption, but is there really a problem explaining the emission process via the Schroedinger equation?

 

[Demystifier]

I know there is a problem with describing absorption, but is there really a problem explaining the emission process via the Schroedinger equation?

If we talk about the emission of electron (described by Schrodinger equation), then yes. In Schrodinger theory, electron lives forever, it is neither created nor destroyed.

If your will say now that creation and destruction are described by QFT, I have a ready objection too.

 

[Demystifier]

FrameDragger, if you're trying to convince her to come back, you're doing it really badly.

Rkastner, I don't think there was any unfriendly stuff in this thread until after you started saying that there was. When you started this thread, you said that the article you're working on will "address questions, confusions, or concerns about TI". We certainly don't need to study the original article to have questions or concerns (or confusions, ) about the TI, so I don't see how the type of responses you got could surprise you or offend you.

Obviously, rkastner writes an article for people who already read other relevant literature on TI. There is nothing wrong with it, after all ANY article assumes that readers already know something, and there are allways interested readers who do not satisfy that assumption. You cannot write an article for everybody.

Of course, we all here would like to see a pedagogic modernly written paper for those who know nothing about TI, but that's not what rkastner is attempting to write.

 

[Dmitry67]

Obviously, rkastner writes an article for people who already read other relevant literature on TI. There is nothing wrong with it, after all ANY article assumes that readers already know something, and there are allways interested readers who do not satisfy that assumption.

Well, TI is not commonly accepted. For such questionable things one can't assume that people know it, or support it. You always need to 'sell' that thing by answering ANY questions, even the "not friendly" ones, which she failed to do.

 

[Dmitry67]

If your will say now that creation and destruction are described by QFT, I have a ready objection too.

I am intrigued :)

 

[Frame Dragger]

FrameDragger, if you're trying to convince her to come back, you're doing it really badly.

Rkastner, I don't think there was any unfriendly stuff in this thread until after you started saying that there was. When you started this thread, you said that the article you're working on will "address questions, confusions, or concerns about TI". We certainly don't need to study the original article to have questions or concerns (or confusions, ) about the TI, so I don't see how the type of responses you got could surprise you or offend you.

I was attempting something closer to the opposite. I have no patience for drama queens in scientific fields. If that's who you are, fine, go act or sing or join a theatre troupe, but please stay out of intellectual endevours.

Anyway, I'm far more interested to hear Demyst's ready objection at this point. This is an area where I'm truly uninformed, and a debate between Dmitry67 and Demystifier is bound to be more informative and entertaining than someone who starts a thread and then runs away in a huff.

Oh... and I AM the son of a single mother, and I really DON'T appreciate women pulling this kind of thing; some men expect women to cut and run (especially in science) when challenged, and it makes me ill to see someone do just that.

@Demystifier: That is a very kind way of telling someone that if they want to simply espouse a theory, then try a non-educational site. I believe there is a booming industry in TFRBs.

 

[conway]

If we talk about the emission of electron (described by Schrodinger equation), then yes. In Schrodinger theory, electron lives forever, it is neither created nor destroyed.

I don't see the problem with emission. Are you talking about the photo-electric effect? There are populated states in the metal, and there are unpopulated free states outside the metal. The incident radiation introduces a coupling term between the bound states and the free states. The electron wave which was occupying one of the bound states mixes into the free state until there is nothing left of it in the metal. Isn't that all exactly described by the Schroedinger equation?

 

[DrChinese]

In view of the ongoing irresponsible posts, I will not longer check or respond to this thread.

Thanks again to those of you with the decency to do some basic reading and ask well-informed questions.

RK

I hope you reconsider. This board consists of a variety of readers. Some are physics professionals, and many of those do original research. There are also novices, students and amateurs - all with varying degrees of polish and expertise.

While you may have come here with a specific purpose and expectation, I suggest you would gain from a fluid interaction with other readers. Cramer's work has been discussed here a number of times previously, and there are a lot of points which have been soundly debated. I think if you will forgive the rough edges to some of the conversions, you will discover that the meat of the argument is taken quite seriously by many.

For example: The TI - as I understand it - involves certain elements of time symmetry in that there are advanced and retarded interactions. There are other time symmetric interpretations as well, such as relational blockworld (RBW). So, how does TI compare to RBW? Are they somewhat similar or radically different?

 

[cesiumfrog]

Ruth, would you clarify, do you agree or disagree that TI allows Schroedinger's cat to have actually been in a superposition of "having forgotten dreaming about mice" and "having forgotten dreaming about fish"?

Look at decoherence. [..] In TI, the same mathematics obtains--an extremely small prob. of a superposed cat--and you have an account of determinate outcome[..]

That's an evasive yes, right, qualitatively?

I've had several discussions with John about the Transactional Interpretation, including one delightful dinner on the eve of a meeting we were both going to, and I can tell you that John's own view about whether this is a theory or not - i.e. makes different predictions from standard QM or not - is neither clear nor constant.

If TI features superpositions of buckyballs and cats, why does Cramer say it avoids the problem of determining when the collapse occurs? Say Wigner's friend performs an experiment on the cat: if this friend's lab is arbitrarily well isolated we can describe his period of solitude (from Wigner outside) as a transaction, so the lab will actually have contained (in parallel) the infinite number of friends who all contribute non-zero amplitude to the two definitive states of Wigner's friend before and after his period of solitude (but who differ subtly, such as in the exact moments they closed or opened the cat's box). But according to each one of those parallel-friends, at the moments when the cat's box was open (and not the moments in between) the cat was similarly in a definitive state. But Wigner himself knows this isn't entirely true (and that his friend is mistaken about whether the transaction was complete) since there exists a moment when only some of the parallel components of his friend had opened their respective cat's box. Even though Wigner and his friend are both applying TI, it gives them mutually incompatible answers about the reality of the cat.

We could go further, explicitly treating each atom in the lab (nay, universe) individually according to TI, and then we'd need the very framework that is being developed for MWI, just to understand how each of the parallel "Wigner's friend"s ever perceived himself to be experiencing a consistent history.. It seems to me that TI is trumped by dBB if it does not allow superpositions of buckyballs, by CI if it does but not of cats, and by MWI otherwise.

 

[Demystifier]

I don't see the problem with emission. Are you talking about the photo-electric effect? There are populated states in the metal, and there are unpopulated free states outside the metal. The incident radiation introduces a coupling term between the bound states and the free states. The electron wave which was occupying one of the bound states mixes into the free state until there is nothing left of it in the metal. Isn't that all exactly described by the Schroedinger equation?

That's all correct, but that's not what I'm talking about. What you are talking above has nothing to do with emission in the sense of TI, which is related to genuine creation of the electron wave function which did not exist before.

 

[Demystifier]

I am intrigued :)

Without a collapse, a state in QFT is typically a superposition of states with DIFFERENT numbers of particles. On the other hand, in experiments you observe a definite number of particles. In standard QFT, you describe it by the collapse. In a transactional interpretation of QFT (I don't know if it really exists), you need a generalization of absorption/emition that replaces THAT sort of collapse.

 

[Dmitry67]

Ah, yes, I see.
In any case, I think TI is incompatible with QFT for the reasons I explained above:
a) QFT uses emission/absorbtion almost everywhere and it does not cause any collapse;
b) QFT does not make principal difference between exchange of photons, W,Z, g or any other partcles

 

[Frame Dragger]

Ah, yes, I see.
In any case, I think TI is incompatible with QFT for the reasons I explained above:
a) QFT uses emission/absorbtion almost everywhere and it does not cause any collapse;
b) QFT does not make principal difference between exchange of photons, W,Z, g or any other partcles

Given that the OP tucked-tail and ran, I'm guessing that we'll have to wait until another TI "expert" shows up.

"b" for me is the damning one btw... "a" is a problem with other problems attatched in other interpretations.

 

[Count Iblis]

I hope you reconsider. This board consists of a variety of readers. Some are physics professionals, and many of those do original research. There are also novices, students and amateurs - all with varying degrees of polish and expertise.

While you may have come here with a specific purpose and expectation, I suggest you would gain from a fluid interaction with other readers. Cramer's work has been discussed here a number of times previously, and there are a lot of points which have been soundly debated. I think if you will forgive the rough edges to some of the conversions, you will discover that the meat of the argument is taken quite seriously by many.

For example: The TI - as I understand it - involves certain elements of time symmetry in that there are advanced and retarded interactions. There are other time symmetric interpretations as well, such as relational blockworld (RBW). So, how does TI compare to RBW? Are they somewhat similar or radically different?

How will Rkastner respond to this friendly offer wave?

 

[Dmitry67]

How will Rkastner respond to this friendly offer wave?

I collapsed of laughter when I read your post!

 

[Frame Dragger]

I collapsed of laughter when I read your post!

The retarded wave had already informed her that it was coming!

 

[rkastner]

Hi, folks. My email is easily locatable by anyone who wanted to seriously discuss TI with me, and given time constraints, I have responded to everyone who contacted me with well-informed questions or concerns about TI. Those of you who continue to have questions are welcome to do so. I think you'll find that nobody (of either gender) will want to spend a lot of time responding to frankly ill-informed and insincere comments; but not everyone will be willing to tell you that's why they're not replying. I respected this Forum enough to be straightforward about these circumstances.

All best, RK

 

[rkastner]

Dmitry, anything that is described by a current in QFT, which can couple to other fields, can be an absorber. A confirmation wave is generated when an annihilation operator acts with certainty (i.e., destroys the incoming quantum state); this is the case in, e.g., relativistic scattering for the free 'outgoing particle'. I stopped replying to the TI thread when people (including yourself) indicated they weren't interested in reading the basic material (eg Cramer's 1986) about TI. How can you expect to participate in a well-informated manner if you haven't read the basic material first?

Thanks for your interest,

RK

 

[rkastner]

Follow-up to question by Dmitry on what constitutes an absorber in TI: the demand for an algorithm for 'yes' or 'no' [as to whether something acts as an absorber] presumes a lot both methodologically and ontologically which is not necessarily appropriate for the quantum realm. Consider a relativistic scattering process, in which coupling at vertices have an amplitude less than unity (eg the fine structure constant). Under PTI (my possibilist version of TI) this is the amplitude for a confirmation wave (CW) to be generated. This applies to any coupling between microscopic currents. Macroscopic absorbers contain millions of such currents, so the probability that such an object will generate a confirmation is close to unity. That is what a macroscopic absorber is: a collection of enormous numbers of microscopic currents capable of coupling to fields and of therefore generating a CW somewhere in the macroscopic object (and we generally cannot know which microscopic current was the source of the CW).

RK

 

[Jacques_L]

Thank you Mrs Kastner to have opened this discussion.

Some years ago, your previous paper http://arxiv.org/PS_cache/quant-ph/pdf/0502/0502021v3.pdf" had been thrown to my face by someone (a bellicose pervert).

I am very glad to read how much you have evolved since, and how your own theorizing has deepen in the meantime.

However, I maintain that one of the necessary sources of the TIQM has not yet percolated up to the american physicists. For them, what is not published in english, simply does not exist. Albert Einstein, Arnold Sommerfeld and Erwin Schrödinger took care of reading the thesis of Louis Victor de Broglie, and read it in french.
http://tel.archives-ouvertes.fr/docs/00/04/70/78/PDF/tel-00006807.pdf
At least the Nobel lecture is in english :
http://nobelprize.org/nobel_prizes/physics/laureates/1929/broglie-lecture.pdf


Unfortunately, Schrödinger was defeated at the Solvay congress in 1927.

Sorry, there is not yet any english translation of my page on TI : http://deonto-ethics.org/mediawiki/index.php?title=Interpr%C3%A9tation_transactionnelle" .

What have been thrown into the Memory Hole by the winning pack was the intrinsic frequency : $\nu_e = \frac{m.c^2}{h}$
and the theorem of Harmony of phases. Broglie deduced that the phase velocity V should be c² / v : $V = \frac{c^2}{v}$
So in the frame of the electron, the electron is everywhere in phase with itself, and cannot become punctual, never.
An unavoidable consequence that Broglie has never perceived, is that every quanton dwells in the noise of the broglian waves of all the others. No screen for that...

In that permanent noise, sometimes a complete handshake can achieve : same frequency (beat between final and initial state), same polarization, same phase...

The malediction on the astronomers is that the emitting regions are hot and obvious, though the absorbing ones are not.

During eighty years, nobody noticed that in 1927, Erwin Schrödinger had not yet the right equidistance for explaining the Compton diffusion by a Bragg diffraction (Über den Comptoneffekt; von E. Schrödinger. Annalen der Physik. 1927, 28, 257-64. http://www.apocalyptism.ru/Compton-Schrodinger.htm), and that he found it in 1930, but without exploiting it. And oddly enough, nobody corrected it after 1930, including Schrödinger himself.

By a way or another, TIQM was unavoidable. Pity is that did not occur in the 1930 or so years. A huge waste of time, and waste of physicists

 

[DrChinese]

...
What have been thrown into the Memory Hole by the winning pack was the intrinsic frequency : $\nu_e = \frac{m.c^2}{h}$
and the theorem of Harmony of phases. Broglie deduced that the phase velocity V should be c² / v : $V = \frac{c^2}{v}$
So in the frame of the electron, the electron is everywhere in phase with itself, and cannot become punctual, never.
An unavoidable consequence that Broglie has never perceived, is that every quanton dwells in the noise of the broglian waves of all the others. No screen for that...

In that permanent noise, sometimes a complete handshake can achieve : same frequency (beat between final and initial state), same polarization, same phase...

The malediction on the astronomers is that the emitting regions are hot and obvious, though the absorbing ones are not.
...

Welcome to PhysicsForums, Jacques_L!

You have made some very interesting comments about this subject. I especially like the commentary about the emitting and absorbing regions. So I wanted to ask your personal opinion, and it relates to this. Some people say that a photon is an "excitation" or similar, with the sense that it does not have an independent wavefunction. I.e. it is more of a mathematical artifact. Do you think that photons can exist freely? By this I mean: I would imagine that stars emit light that would never arrive anywhere. If so, would that contradict the idea that photons do not have an independent wavefunction?

Or is my question poorly formed (or sadly misinformed)? Or perhaps someone else can help me here!

 

[Jacques_L]

Welcome to PhysicsForums, Jacques_L!

You have made some very interesting comments about this subject. I especially like the commentary about the emitting and absorbing regions. So I wanted to ask your personal opinion, and it relates to this. Some people say that a photon is an "excitation" or similar, with the sense that it does not have an independent wavefunction. I.e. it is more of a mathematical artifact. Do you think that photons can exist freely? By this I mean: I would imagine that stars emit light that would never arrive anywhere. If so, would that contradict the idea that photons do not have an independent wavefunction?

Or is my question poorly formed (or sadly misinformed)? Or perhaps someone else can help me here!

I do not know enough to conclude.
As I think as a transactionnist myself, my answer begins so :
A photon is the successfull electromagnetic transaction between an absorber and an emitter. It begins by a handshake emerging form the ambiant broglian and chaotic noise, it continues by a synchroneous transfer (momentum and energy), and ends by a disconnecting when a whole quantum of action is transferrred, and return to the chaotic usual noise, for both the emitter and the receiver.

Clear and cut ? NO !

The above sentence is oversimplified, as it has omitted a third kind of partners in the transaction : the vacuum and/or the matter in the middle, mirrors or lenses for instance, sometimes gravitational lenses at the astronomical scale, gratings, other synchroneous photons, etc.

The Maxwell equations remain valid at the scale of a photon, at least in the vacuum.

At the surface of the metals, there is also a coupling between the conduction electrons and each photon, that confers a temporary mass to the photon.

Each one of these couplings with the electronic clouds of matter, temporarily confers a mass to the photon. As far as I know, there is no photonic mass in the vacuum.

Above, I have only set a theoritical frame of a two partners transaction, as Cramer did in 1986. And I am sure it is not enough. Even the first problem dealed by Planck in 1900 involved the space between emitters and absorbers.

We need a three partners transactionnal theory, and I am unable to set it. As Ruth Kastner wrote it above (end of page 1), our macroscopic space is just a statistical emergence. It is beyond my means to mathematize that.

If the space in-beween did not intervene, the photons would not be bosons at all. The astronomy by large basis interference would not work at all.

The mere fact that large basis interferometry works proves that during their long and wide journey, the photons that our distant sensors capture, had time enough to synchronize in frequency and phase.

The photons are special : they travel at null intrinsic time (and null intrinsic frequency). They do not bother of the lifetime of a physicist, nor of his/her pride. For us, it may be very important for our pride that photons bang in an absorber during our lifetime... But does it matter for intrinsic and impersonal physical laws ?

 

[Jacques_L]

Cannot more edit, must quote in a new message...

If the space in-beween did not intervene, the photons would not be bosons at all. The astronomy by large basis interference would not work at all.

The mere fact that large basis interferometry works, proves that during their long and wide journey, the photons that our 10 km or 20 km distant sensors capture, had time enough to synchronize in frequency and phase.

So you are right, photons remain "an excitation" of the vacuum, besides being a successful transaction between an absorber and an emitter. The prove is that they interact as bosons.
The theoritical synthesis remains to be done, as far as I know (and I know little).

 

[Ken G]

Another point to ponder is the role of the observer/perceiver/conceptualizer in all this. The transactional approach seems to be one of the "realist" interpretations, in that it attempts to limit its interpretation to events that are "really happening", and would be happening even without an observer to register the happening. But what of the role of hypothetical observers, has the transactional approach really banished a role for them? In my opinion, no, because the very spirit of a "transaction" as being the physically actualized event screams "role of the observer" to me. As we heard above, the guts of the PTI is that reality plays out on two planes at once-- an actualized plane of completed transactions, and a descriptive plane of possibilities that rule, in a statistical way, what is actualized. If you knew no physics, what would that language sound like to you? It would sound like exactly the way our minds deal with our uncertain surroundings-- the actualization of potentialities, where we can find rules that govern the potentialities but no rules that determine the actualities. That sounds just like the kinds of limitations our thinking encounters in our daily lives, so although quantum mechanics is often painted as the "weirdest" arm of physics, I think it is the subfield that makes it the most clear the imprint that our own thinking process leaves on our physical descriptions of reality. Is a transaction something that really happens without any hypothetical observer present, or is it just something that we require to happen, in our approach to realism?

 

[Jacques_L]

Another point to ponder is the role of the observer/perceiver/conceptualizer in all this.

Strictly not any in physics.
But it/he/she plays the central role in positivism.
And a pack of positivists took over in 1927. Since then, they are the winning pack and wan all the holding on the teaching apparatus.

 

[Fyzix]

Just a quick question: is TI 100% deterministic?

 

[Ken G]

Actually, I would argue that recognizing the role of the observer is exactly the escape from excessive positivism. Positivism as a philosophy is a claim on reality, that only what we can objectively observe should count as what is real. But in science, positivism is not a claim on reality, it is merely a claim on science-- so we say, if we can't objectively observe it, it doesn't fall within the purvey of science, but we don't claim the purvey of science is all that is real because that is not something that any science could ever falsify. Hence, noting the essential role of the observer in everything we call science is how we can tell the difference between what is science, and what is philosophy.

 

[Ken G]

Just a quick question: is TI 100% deterministic?

No-- it is clear from the above that TI is the opposite of deterministic, because it places at the level of an axiom the stochastic nature of the transactions that get actualized. Thus, it asserts from the start that god does in fact roll dice.

 

[Jacques_L]

Just a quick question: is TI 100% deterministic?

We do not change the formalism.
We do not change the known laws. Or not yet.
They remain strictly undulatory and strictly deterministic.
It does not imply a deterministic physics. Not at all.
Simply because of the unavoidable broglian noise. This simple fact ruins any panoptical fantasy. There are no ways to know any kind of "initial conditions", nor on the absorber, nor on the emitter, nor on any other intervening parties.

The involved frequencies, and the crushing mass of transient facts to recorder, are far beyond (even future) human possibilities. And the Avodagro constant and the W.R. Ashby's theorem on requisite variety are unbreakable barriers.

 

[Fyzix]

Thanks.

Ok if it is indeterministic put me in the "TI is definitely wrong" opinion category.
There is no way the fundamental reality is indeterministic...

I'll let you guys keep debating though.

 

[Jacques_L]

Actually, I would argue that recognizing the role of the observer is exactly the escape from excessive positivism. Positivism as a philosophy is a claim on reality, that only what we can objectively observe should count as what is real. But in science, positivism is not a claim on reality, it is merely a claim on science-- so we say, if we can't objectively observe it, it doesn't fall within the purvey of science, but we don't claim the purvey of science is all that is real because that is not something that any science could ever falsify. Hence, noting the essential role of the observer in everything we call science is how we can tell the difference between what is science, and what is philosophy.

I do not agree with the amalgam :
The "observer" and the hativous slogans on the "observer" are not a good replacement for the necessary fine physics of the sensors.

 

[Jacques_L]

Thanks.

Ok if it is indeterministic put me in the "TI is definitely wrong" opinion category.
There is no way the fundamental reality is indeterministic...

I'll let you guys keep debating though.

Can you predict when a particular Thorium nucleus will decay ?

 

[Fyzix]

Can you predict when a particular Thorium nucleus will decay ?

Obviously not, but what sort of argument is that?
If I bring you to the top of the empire state building and throw 2 dice off the edge, will you be able to predict where they will fall and what sides will turn up? Ofcourse not, because you don't know all the variables yet.

we do not have a ToE so atm atomic decay seem random.

 

[Ken G]

The problem with the claim that "reality must be deterministic" is that it does not flow from a logical argument. Determinism is actually a property of a theory or model, so one can only pass the aspects of a theory or model to the aspects of reality if one believes one has good reason to do so. However, in the history of science, plenty of good reasons to pass from aspects of theories to aspects of reality have fallen by the wayside. Indeed, the failure of that program is one of the most constant aspects of all in physics. The history of physics is very demonstrably a history of maps that were not the territory.

Presumably, those who maintain that the quality "deterministic" can be successfully passed from theory to reality do so on the strength of the success of deterministic models. They see the advancement of science as a gradual loosening of the hold of the pernicious and fickle desires of ill-defined gods, and a replacement by the block-steady rules of law embodied in well-defined physics equations. None can dispute the successes of the latter approach, and yet it still falls short of a logical syllogism. That which works never becomes the truth, no matter how well it works, unless it happens to also be the truth. Which well-worked theorem of physics happened to also be the truth? I'm am unaware of a single example. So those who maintain that determinism is true seem to do so only with a substantial helping of willingness to overlook facts.