[majorminor]

The other branches aren't physically accessible/real from your branch perspective.

But then I am confused. If the other branches are not physically real and accessible from my branch, why should I believe they exists?
Is it even scientific to believe in something that is not physically real and accessible?

What is the difference between believing in 'ghosts' or 'spirits' and believing in universe branches that are not physically real and not physically accessible?

Maybe they are not real and accessible Yet. On a different time arrow only accessible by faster than light travel.(i know not possible in our universe)
And with theories, are we really meant to believe in them, are they not just an attempt to explain something with the best guess from the available data?(maybe I am playing with words)
I have thought often about the multi-verse explanation of things and think there is something to it. Is there somewhere a King Flr I ? Do there have to be so many multi-verses  if the universe can be predetermined in many ways- as in, there is a finite number of times it can branch. We all have pivotal moments in out life, are those the small moments of free will we have? Silly Idea maybe and in the wrong topic.

[flr]

And with theories, are we really meant to believe in them, are they not just an attempt to explain something with the best guess from the available data?

At the foundation of any physical theory should be empirical "available data" from our measurable and observable universe.
A physical theory must explain what we observe here in the word we live and can measure, and not a inaccessible universe branch in which  King Flr I might a butterfly.

A more conservative view would seem to  me to consider both string theory and MWI as mathematical constructions; they would became physical theories when experiments prove the reality of strings and of other universe branches.

[dlorde]

But then I am confused. If the other branches are not physically real and accessible from my branch, why should I believe they exists?

Belief is a personal prerogative. Science doesn't have anything to say about belief. The MWI provides an interpretation of QM that is the implication of taking the universe to consist of an evolving wavefunction. It conforms with the physics of QM in the most literal sense, and with experiment. If you don't find it useful, try a different interpretation - but you'll find they have other problems. QM is like that - the physics and experimental results don't make intuitive sense.
 

Is it even scientific to believe in something that is not physically real and accessible?

As I said, science is not about belief. Also, these QM interpretations aren't strictly scientific; they aren't testable or falsifiable, they're just interpretations; attempts to find a way to visualise an unintuitive theory.

If you prefer the Copenhagen interpretation (the collapse of the wavefunction), by all means go with that. Personally, I find the arbitrary nature of wavefunction collapse problematic; and although Hiesenberg's explanation that it represents the state of our knowledge of the system rather than the state of the system itself seems more reasonable, it leaves what's happening in/to the system uninterpreted...

What is the difference between believing in 'ghosts' or 'spirits' and believing in universe branches that are not physically real and not physically accessible?

Ghosts and spirits have no supporting physical theory, and in fact would contradict fundamental physical and biological principles, not least the laws of thermodynamics. Such evidence as there is is either unsupportably weak, or has reasonable mundane explanations, etc. MWI is based on the physical theory and doesn't contradict any fundamental principles.

As I already mentioned, many physicists find QM interpretations problematic, hence the "shut up and calculate" maxim. Others find them useful for generating new ideas and new experiments. MWI is one of the most popular intepretations because it fits the physics, is generally simpler (once you accept the premise), and has fewer awkward issues than the others.

[dlorde]

... with theories, are we really meant to believe in them, are they not just an attempt to explain something with the best guess from the available data?(maybe I am playing with words)

That's roughly the way I see it. We have the maths-based physical theories, we have experimental data that supports them, and we try to find useful non-mathematical ways to think about them (visualise them).

[Pmb]

Ghosts and spirits have no supporting physical theory, and in fact would contradict fundamental physical and biological principles, not least the laws of thermodynamics.

In what way do you assert that the presence of a ghost would contradict the laws of thermodynamics? Which law? How does it violate it/them?

To a certain extent, I disagree. I.e. in a limited sense there is a "theory" regarding ghosts. They are considered to be the disembodied consciousness of a person who was previously alive. In other words its a consciousness which is decoupled from its original form and matter.

I see no connection to fundamental biological principles so I don't see how their existance would violate them. There is nothing to suggest that a ghost should have any biological nature whatsoever. To say that it contradicts any physical principle is merely a prediction of what will not be observed. It in no way dictates what actually exists in nature. Once its observed then that principle has to either be modified or discarded.

Consider the fish know as the Coelacanth. They were believed to have been extinct since the end of the Cretaceous period. Does that mean that they don't exist? That is merely a prediction. I.e. one should not expect a Coelacanth to be found. Then, wonder of wonders, one was caught in 1938.

It used to be assumed that energy is always conserved. Then came Einstein who created the theory of general relativity. In that theory one cannot even in generaly define the energy in a gravitational field.

Also it should be noted that we might have ideas of what we observe and yet be totally wrong as to its nature.  For example: one day I was standing in the kitchen looking with lust into what we used to call the candy closet when I felt a hand placed firmly on my back. I quickly turned around and nobody was there. It freaked me out of course. Perhaps my mind played a trick on me. Perhaps my mind didn't play a trick on me. I'll never know. But I know that freaky things happen in this world. My old physics advisor told me of something that happened to him a few years ago. It was truly bizarre and I've known him for thirty years now and know that the man doesn't know how to lie.

It's a matter of scinetific philosophy that a law of physics is something which describes what is observed in nature. However whatever is observed is consistent with physical reality whether the laws of nature are what we think they are or not.

Here is a  important comment from the paper which put forward the concept of tachyons, i.e. Possibility of Faster-Than-Light Particles by G. Feinberg, Physical Review, Vol. 159(3), July 25, 1967

.. no observation can be logically inconsistent.

The author credits someone named Dr. M. Tauser for this remark. The only thing that comes into question is whether these things have actually been observed and whether there was no confusion about what was being seen (i.e. he wasn't drugged and David Copperfield wasn't around etc.).

Just because we don't or can't explain it that doesn't mean we don't have any theories on it. What do I mean by this apparent contradiction? I mean the following: a theory is a the analysis of a set of facts in their relation to one another. The facts are the laws aka postulates. Laws are not explanations, they are descriptions. Deductions made from the laws of nature are what we commonly known as explanations. A theory is a collection of laws/postulates. E.g. consider the following two postulates

(Postulate 1) The laws of nature in all inertial frames of reference are invariant with respect to a Lorentz transformation.
(Postulate 2) The speed of light is invariant, i.e. has the same value in all inertial frames of reference.

The set consisting of those two postulates is called The special theory of relativity.

Theories or descriptions of nature need not be complete and we need not know the mechanisms behind them. Newton's Law of Gravity is a good example

When Newton first set force his theory of gravity he did not make any attempt to explain any mechanism to explain why one body should influence another, distant, body with no apparent mechanism for affecting it. It was an action at a distance. Just as spooky as a ghost would be. It's influence was invisible to the naked eye. All Newton was able to do was to describe the dynamics according to the relationship dp/dt = GMm/r^2. Beyond that Newton had no idea as to the mechanistm of how gravity works. To be precise Newton said

I have not as yet been able to discover the reason for these properties of gravity from phenomena, and I do not feign hypotheses. For whatever is not deduced from the phenomena must be called a hypothesis; and hypotheses, whether metaphysical or physical, or based on occult qualities, or mechanical, have no place in experimental philosophy. In this philosophy particular propositions are inferred from the phenomena, and afterwards rendered general by induction.

As I already mentioned, many physicists find QM interpretations problematic, hence the "shut up and calculate" maxim.

Wow! Talk about bringing back some fond memories!

When my advisor/professor said this to be a wave of comfort passed over me. It was at that time that I knew I wasn't missing something fundamental and thus knew the theory and was just as confused as they next guy.

So, given that do I believe that there is a complete theory of ghosts which lends itself to experimentation? No. I hold that there is a theory and that is all. But I also know that there are things in nature that science is not equipped to handle. Such things are what I call atmospheric anomalies. That is to say phenomena observed by people who are not ignorant and not goofy but are unable to explain what they observe even when they make the effort to explain it in scientific terms. I've had experiences like that myself. Am I saying that its a complete theory which is not problematic on many levels? No.  accept as true that phenomena arise in nature which is so brief and rare in its occurance so as not to lend itself to scientific observation and analysis.

There was a lab at Princeton University which operated for thirty hears called the Princeton Engineering Anomolies Lab whose purpose was the Scientific Study of Consciousness-Related Physical Phenomena. You can learn more about it at http://www.princeton.edu/~pear/  . I'm sure that you know that this is the university where Einstein worked and is an Ivy Leauge University which is highly respected across the world. Something I believe should not be looked down upon by any stretch of the imagination.

They investigated things that you would never have read in any physics textbook. They have hard data from numerous scientific experiments.

What I found interesting is this http://www.princeton.edu/~pear/experiments.html

In these studies human operators attempted to bias the output of a variety of mechanical, electronic, optical, acoustical, and fluid devices to conform to pre-stated intentions, without recourse to any known physical influences. In unattended calibrations all of these sophisticated machines produced strictly random data, yet the experimental results display increases in information content that can only be attributed to the consciousness of their human operators.

[dlorde]

In what way do you assert that the presence of a ghost would contradict the laws of thermodynamics? Which law? How does it violate it/them?

1st & 2nd. They would be doing work without an energy source or means of conversion.

To a certain extent, I disagree. I.e. in a limited sense there is a "theory" regarding ghosts. They are considered to be the disembodied consciousness of a person who was previously alive. In other words its a consciousness which is decoupled from its original form and matter.

I see no connection to fundamental biological principles so I don't see how their existance would violate them. There is nothing to suggest that a ghost should have any biological nature whatsoever.

Consciousness is a process. It is a subset of the functions of a living, physical brain. It is currently a biological process, and until we can produce machine consciousness, it is likely to remain so.

Also, if 'disembodied' means non-physical, how can the non-physical absorb or refract light? produce sound? interact with people?
If it doesn't mean non-physical, what does this 'theory' propose it consists of? how might it be sustained? how could it achieve the claimed interactions?

Consider the fish know as the Coelacanth. They were believed to have been extinct since the end of the Cretaceous period. Does that mean that they don't exist? That is merely a prediction. I.e. one should not expect a Coelacanth to be found. Then, wonder of wonders, one was caught in 1938.

What has this to do with the price of fish? We already had incontrovertible evidence that coelocanths had existed. It was surprising to find they had persisted, just as it would be surprising to find dodos on a remote island. But so what?

It used to be assumed that energy is always conserved. Then came Einstein who created the theory of general relativity. In that theory one cannot even in generaly define the energy in a gravitational field.

As far as I am aware, neither general relativity nor quantum mechanics have undermined the principle of conservation of energy. There may be doubt whether it is conserved for the whole universe, and in GR it applies to a single reference frame over time, and QM has also introduced a temporal qualification, but the energy of a closed system is always conserved. Unless you can point to some observations to the contrary?
 

Also it should be noted that we might have ideas of what we observe and yet be totally wrong as to its nature.

Quite. It seems to me that's just how it is with ghosts and other such paranormal or supernatural phenomena.

I was standing in the kitchen looking with lust into what we used to call the candy closet when I felt a hand placed firmly on my back. I quickly turned around and nobody was there. It freaked me out of course. Perhaps my mind played a trick on me. Perhaps my mind didn't play a trick on me. I'll never know.

What other reasonable explanations can you come up with?

But I know that freaky things happen in this world. My old physics advisor told me of something that happened to him a few years ago. It was truly bizarre and I've known him for thirty years now and know that the man doesn't know how to lie.

Improbable and sometimes bizarre coincidences can and do happen - that's the normal workings of the laws of probability, the law of big numbers. Also, many people believe that quite extraordinarily bizarre paranormal things have happened to them, or they've witnessed such things. But there's no good evidence for such things being real, despite years of investigation. In recent years we've discovered just how unreliable human perception, memory, and recall really are, and while many of these claims remain unverified for lack of evidence, most of them fall into categories for which there are quite reasonable, but mundane, explanations. As the late, great Richard Feynman said: "The first principle is that you must not fool yourself, and you are the easiest person to fool". In the years since he said that, we have discovered just how easily we can fool ourselves and be fooled.

If you'd like some interesting links about the fallibility of perception, memory and recall, I can post them up here. It's quite an eye-opener.

It's a matter of scinetific philosophy that a law of physics is something which describes what is observed in nature. However whatever is observed is consistent with physical reality whether the laws of nature are what we think they are or not.
...
The only thing that comes into question is whether these things have actually been observed and whether there was no confusion about what was being seen...

Quite. That is the main consideration. Hence the scientific method.

So, given that do I believe that there is a complete theory of ghosts which lends itself to experimentation? No. I hold that there is a theory and that is all.

But I also know that there are things in nature that science is not equipped to handle. Such things are what I call atmospheric anomalies. That is to say phenomena observed by people who are not ignorant and not goofy but are unable to explain what they observe even when they make the effort to explain it in scientific terms. I've had experiences like that myself.

For example?

Claiming to have a theory or hypothesis is OK. Claiming that science can't handle stuff is OK, but you can't have a (scientific) theory or hypothesis that science can't handle. That's a simple error of logic. Either it's scientific or it isn't.

Am I saying that its a complete theory which is not problematic on many levels? No.

It's not a scientific theory in any sense - because it's not a 'well-substantiated explanation of some aspect of the natural world, based on a body of facts that have been repeatedly confirmed through observation and experiment'. It may not even a scientific hypothesis, unless you can propose some way to test it?

There was a lab at Princeton University which operated for thirty hears called the Princeton Engineering Anomolies Lab whose purpose was the Scientific Study of Consciousness-Related Physical Phenomena. You can learn more about it at http://www.princeton.edu/~pear/  . I'm sure that you know that this is the university where Einstein worked and is an Ivy Leauge University which is highly respected across the world.

Yes, I'm familiar with some of the work done by Jahn and co. at Pear.

They investigated things that you would never have read in any physics textbook. They have hard data from numerous scientific experiments.

In these studies human operators attempted to bias the output of a variety of mechanical, electronic, optical, acoustical, and fluid devices to conform to pre-stated intentions, without recourse to any known physical influences. In unattended calibrations all of these sophisticated machines produced strictly random data, yet the experimental results display increases in information content that can only be attributed to the consciousness of their human operators.

After years of research and thousands of experiments, their results were marginal, and a number of critiques (e.g. Jeffers, et al.) have indicated various ways in which errors might have crept in to the experimental method and analysis. Even very minor errors of calibration or analysis would be sufficient to skew a random baseline sufficiently.

A solid body of evidence, independently replicated, would have made a major impact. Unfortunately replication was problematic. PEAR themselves got two German universities to run their random interference experiments, but they couldn't replicate the results. Other independent attempts to replicate have had similar difficulty. In light of this, the additional lack of any theoretical basis for their claimed results was probably the clincher for many who'd initially taken an interest.

[Pmb]

1st & 2nd. They would be doing work without an energy source or means of conversion.

What work are you referring to? I see no obvious reason to assume that a ghost is devoid of a source of energy. Please clarify your explaination for me. I think that one has to keep in mind that just because we have never observed a phenomena siuch as the ghosts energy source it doesn't mean that it doesn't exist. History is chuck full of examples such as this.

Consciousness is a process. It is a subset of the functions of a living, physical brain. It is currently a biological process, and until we can produce machine consciousness, it is likely to remain so.

I disagree. Again, its unwise to assume that because we haven't observed something that it doesn't exist. Perhaps the computer analogy would be helpful here. Think of the brain as a computer as an analogy. We, our spirit if you will, might be analogous to a computer program. TGhe brain might die and leave behind the program, i.e. us. Perhaps there is a structure which we are unable to interact with into which our "program" resides after death.

[dlorde]

What work are you referring to?

Haunting, poltering, wailing, clanking chains, putting crazy ideas into people's heads - you know, what ghosts do

I see no obvious reason to assume that a ghost is devoid of a source of energy. Please clarify your explaination for me. I think that one has to keep in mind that just because we have never observed a phenomena siuch as the ghosts energy source it doesn't mean that it doesn't exist. History is chuck full of examples such as this.

As I understand it, the burden of proof falls on the claimant. You claim that ghosts may be the disembodied consciousness of a deceased person, but provide no evidence or theoretical basis. I could equally counter that they're actually aliens, or entities from another dimension, or faeries, or they're just figments of the imagination. So you tell me - what's your evidence or theoretical basis for your particular claim? What makes it more reasonable than my suggestions? How and from where do they get their energy? and if they don't use any, how can they exist at all?

Again, its unwise to assume that because we haven't observed something that it doesn't exist.

I'm not assuming that. We have observed the behaviours we call consciousness, and we have seen that when the function of the brain is disrupted in specific ways, consciousness is disrupted in specific ways. These effects are consistent and repeatable, and lead to the conclusion that consciousness is a function of the living brain. There's a mass of evidence to support that, and no evidence to the contrary. It's the rational position to take.

Perhaps the computer analogy would be helpful here. Think of the brain as a computer as an analogy. We, our spirit if you will, might be analogous to a computer program. TGhe brain might die and leave behind the program, i.e. us. Perhaps there is a structure which we are unable to interact with into which our "program" resides after death.

The computer and program is a limited analogy; it is useful in a superficial way, when considering computability, such as the possibility of artificial intelligence and artificial consciousness, but it is limited in precisely the area you're trying to make an analogy in - the brain is a system of neural networks, it doesn't have a program as such; the functionality is built into the structure and connectivity of its components, the neurons. When you learn how to do something, the structure and connectivity is modified. When the brain is damaged the structure and connectivity of the neurons is disrupted. When the brain dies, the neurons die, and their structure and connectivity breaks up and ceases to be functional.

So no, the program doesn't remain after death. Furthermore, if we were to consider the brain literally as a computer with a program, I think you'll find that when the computer dies, the program, stored in memory, dissipates as the power is lost. Turn off your computer while it's running Word, or Grand Theft Auto, and see if you can find the program it was running. Smash it up and see if it's there in the pieces.

And yes, you could possibly rescue a hard disc, or dig out a CD or DVD copy and load it into and run it on another computer, but that would be equivalent to having a backup somewhere of a lifetime's learning, experiences, and perceptions, and somehow loading it into another brain. That information isn't stored anywhere else but the original brain, because it's built into the brain's structure over a lifetime. And if these supposed ghosts are disembodied, they won't have brains to run the program, even if there was a program to run, nor will they have bodies to support the brain they don't have...

'Not even wrong' understates the lack of utility of that analogy in this context.

[Pmb]

As I understand it, the burden of proof falls on the claimant.

I've never accepted that sort of thing myself. People can't prove most of what they experience during an average day. I see no reason to assume that they should be able to prove they saw a ghost. In my book we accept word of mouth by the source. If I describe what I've seen to any friend of mine there's little doubt in my mind that I'd have a hard time convincing anyone of such a thing. The reason being is that I never lie unless it could cause severe injury to myself or someone else and that's never happened to date. My friends trust me since I've always been honest to rhem regardless of the consequences. So when I've explained a strange encounter I had in at night on e long lonely roead in the New Mexico desert with two frinds in a van in 1980 they didn't challenge me and accepted what I said. On the other hand I knew this guy who seemed to lie about everything. You simply couldn't believe what he said, even if you asked him the time of day. I have a friend, my old physics advisor, who told me a strange story. His integrety is such that I believe him without question.

That whole "The burden/onus is on the observer." is a bunch of nonsense to me. To me its just poor reasoning. For example: Suppose you posted what you had for breakfast yesterday. Do you think that you could "prove" it to me? No. Not in the way you used the word above. However if JP were to tell me what he observed then I'd believe him. That's because I've seen what he's posted for a very long time now. He has a great deal of integrety in my book. To me that's proof enough for what he has to tell me in the future.

You claim that ghosts may be the disembodied consciousness of a deceased person, ...

Wrong. I never made that claim. I said that is the theory. It doesn't mean that I accept the theory. I know of nobdy who has ever seen a ghost whose word I trust. That old friend whom I can't believe anything he says claimed that he saw a ghost but, again, I have every reason not to beleve him. Same for all the people who were also there and said the same thing. I could never put my finger on what was going on but my insticts told me that somne was BSing.

[/quote]
'Not even wrong' understates the lack of utility of that analogy in this context.
[/quote]
I see that kind f statement in respone to almost every example that I see used for an analogy in every discussuion forum that I've visitied. Those who respond in this manner to an analogy don't seem to have a solid understanding of the nature of analogies or the precise defintion.

By definition an analogy the inference that two or more things agree with one another in some respects even though they will probably disagre in other ways.

Here is an example of a brain=computer analogy

Both follow algorithms to accomplish certain tasks
Both have inputs and outputs
Both process electrical signals
Both have large memories for information storage and retrieval

Does that mean that the brain is a biological computer and that is exactly what one means when they say that the brain is analogous to a computer? Cetainly not! It only means that they have those things stated above in common. It's assumed that they differ in other ways. If they didn't differ in other ways it would be then that I made a mistake since I wouldn't have been using an analogy. I'd be comparing a computer with a computer or a brain with a brain. There are a multitude of ways in which the brain is different than a computer and, as with any anbalogy, if one takes the analogy too far then you'd be making the mistake of being misleading.

There are some books written by physicists who use this analogy to illustrate some idea or other. Paul Davies wrote such a book. I forget which one it was but I can find out if you want to read it. If you plan on sticking around for a while you should familiarize yourself with the idea of analogies so that you no longer get the idea that two things are analogies if and ony if they are identical in all aspects.

I hope I didn't come across as being pissy about it but I keep seeing people confuse the idea of analog with the idea of identity.

[Pmb]

Haunting, poltering, wailing, clanking chains, putting crazy ideas into people's heads ....

That isn't work being done in the sense a physicist uses the term. Please be more precise next time. When explaining how work is being done physicists don't give examples of a source of energy. They describe specific forces acting over a specific path.(e.g. for the work done on a point particle we calculate a line integral).  Light coming from outside, through my window and into my room is a method of increasing the energy content of my room. In such a case no work is being done.

There are things in nature that have escaped detection even to this day. Two good examples are dark matter and dark energy. Dark energy wasn't even detected until last decade.

Regarding your comment – “What has this to do with the price of fish? We already had incontrovertible evidence that coelocanths had existed.

It was pretty obvious what the purpose of my comment was. I had just made the following a comment

To say that it contradicts any physical principle is merely a prediction of what will not be observed. It in no way dictates what actually exists in nature. Once its observed then that principle has to either be modified or discarded.

I wanted to give you an example of something which was universally assumed to not presently exist in nature alive which was proven false. You mean to say that you didn’t catch that? I’ll try to be more clear in the future.

One aspect of the mind is information. There exist forms of information that has no material medium. It's not even made of atoms. One example that I know of is the information contained in a radio wave.

A well-known physicist, Henry Stapp, proposed a while back that the mind is a quantum effect. I don't know the current status of that idea. If ghosts really exists and are humans whose minds became disembodied then perhaps one way that might conceivably occur might be for that mind to manifest itself as a quantum state impressed onto a highly complex field, which then evolves according to the principles of quantum theory. This is similar to the fact that some human ideas are contained in radio waves. No such complete idea exists as of now and obviously it can’t be said at this point what would be required of the nature of such a field.

There are other kinds of fields in physics that you may never have heard of which can be found in the physics literature. The ones you’ve probably heard of are the gravitational field, the electromagnetic field and the gravitational field, You may not have heard of the Higgs field and the inflaton field.

When the brain dies, the neurons die, and their structure and connectivity breaks up and ceases to be functional.

You've just stated the overly obvious while simultaneously ignoring the details of the statement that you were responding to. I.e. I said

The brain might die and leave behind the program, i.e. us.  Perhaps there is a structure which we are unable to interact with into which our "program" resides after death.

What you did was to completely ignore the part that I've underlined here and response to something I assumed that you and everyone else who reads this is assumed to know.

Our brains work by electrical impulses being "processed” in the brain through nerve cells.  I don't want to get into how signals propagate along nerve cells, firing of synapses, the sodium-potassium pump etc. etc. etc. I'm going to assume you know all of that.

These signals have an electromagnetic component to them. I.e. the brain radiates EM waves (also called brain waves). Those EM waves leave an imprint on the universe by existing in space and time after they leave the brain. Cavemen didn't know that. We know that. It is not inconceivable that people in the future will know a great deal more about the nature of consciousness that we’re just now scratching the surface of. If you’ve ruled out the existence of the soul and spirit then that’s fine by me. As for myself I don’t assume everything that has not been demonstrated to be true beyond all doubt to automatically to be wrong.

Unlike you I'm willing to concede that there are things about the nature of conscience that we don’t know. Perhaps there is something to the mind beyond the nerve cells that we believe constitutes the physical embodiment of the mind. Please note that I'm not claiming that it does. All I'm saying is that I know that there are things the human race doesn't know yet and just perhaps the mind leaves something of itself behind when the physical brain dies.

A man named Henry Stapp wrote about the mind as a quantum effect. I don't know the current status of that idea right now. You might enjoy looking it up and reading about it.

Don't make the mistake that so many people in the world make by assuming that if we don't know about the existence of something then it doesn't exist. Myself, I know that there are strange things in this world and I've personally experienced a couple of them and believe those which my friend described.

For some reason unknown to me you took my comment that some people have a theory about ghosts as me making a claim that there is a valid tested theory that  they exist.  Here's some advice fore you: In the future, if I don't see me say something then there's a good reason for it.

Also please don't put words into my mouth like you did above, i.e. I said

.. in a limited sense there is a "theory" regarding ghosts. They are considered to be the disembodied consciousness of a person who was previously alive. In other words its a consciousness which is decoupled from its original form and matter.

You took that very precisely worded statement and twisted it to mean something else. You read things into what I said and which were never there to begin with. I.e. you  made the following false assertion

You claim that ghosts may be the disembodied consciousness of a deceased person, but provide no evidence or theoretical basis.

First off it is inaccurate to say "You claim ... may be ..." To make a claim is to make a definite statement about the way something is. One doesn't make a definite claim and then imply that it's not certain. In the second place I never made such a claim and here you imply that I did. That's called "putting words into my mouth."  I never made such a claim or assertion. All I said is that it exists. A lot of theories exist which I make no assumptions about whether they are true or false. I never made such a claim because I've never seen a ghost. I have no idea whether they exist or not. I don't even know what to believe myself. A large percentage of scientists believe in God and each has their reason. As far as what things truly are that we observe is an entirely different story. People believe things for a reason. When you read my post you assumed it was written by a person, not a computer or an alien did you not? You had reasons for that assumption. People also have reasons for their assumptions that ghosts exist. Recall that I Said that a large percentage of scientists believe in God. A large percentage of that subset of scientists are Christians who believe the bible. A large percentage of that subset believes that the bible is literally true. In the Old Testament in the Bible King Saul writes of his discussion with the ghost of the Prophet Samuel (1 Samuel 28:11).

You also seemed to imply that if ghosts exist that they could aliens or something else. You really must think that we just toss this stuff out there willy-nilly or you have made a very poor assumption of our scientific skills and knowledge base. In the future, before you make another comment of that nature regarding a term, I highly recommend that you look that term up in a dictionary. That's what I do and this is what I found that applies to this conversation

a disembodied soul; especially : the soul of a dead person believed to be an inhabitant of the unseen world or to appear to the living in bodily likeness

One has to be careful with their choice of words. As with any word used in a conversation in English it is assumed that the meaning of the word is as its defined in the dictionary. If a person means something else then they should say what they mean.

Suppose a person sees something that has the appearance of a partially transparent human which looks like that persons dead relative. Then assuming that it used to be human is not an outrageous assumption. In fact one could even take that to be the definition of a ghost.

[dlorde]

As I understand it, the burden of proof falls on the claimant.

I've never accepted that sort of thing myself.
...
That whole "The burden/onus is on the observer." is a bunch of nonsense to me. To me its just poor reasoning.

It's not about whether you trust your friends; that's entirely your own judgement and prerogative. But in (philosophical) debate, the person making a claim carries an implicit burden of proof. If the claim is contested it is up to the claimant to establish their claim to a reasonable standard. Asking the critic to disprove the claim is fallacious (argument from ignorance). In scientific contexts, a higher standard of evidence is required.

So, for example, if you claim to have seen a UFO and others doubt that claim, for the claim to be taken seriously, you have to supply some evidence to support the claim, otherwise it's just an anecdote. Obviously, if someone you trust tells you they had bacon for breakfast, you have no reason to doubt that claim and no reason to require them to support it. If they tell you they have a live alien in their garage, you might think it reasonable to see the evidence before accepting the claim.

You claim that ghosts may be the disembodied consciousness of a deceased person, ...

Wrong. I never made that claim. I said that is the theory. It doesn't mean that I accept the theory.

OK, I apologise, that's my mistake. But the argument stands - a claim without evidence or theoretical basis, or even reasonable argument, is useless. What you're calling a theory here is just a claim - it has no reasonable theoretical basis or structured argument.

If you plan on sticking around for a while you should familiarize yourself with the idea of analogies so that you no longer get the idea that two things are analogies if and ony if they are identical in all aspects.

I'm quite familiar with analogies and with the brain-computer analogy in particular; my background is human biology and my career has been in computer sciences. I have an interest in neuroscience and computation.

You proposed that taking an analogy between a computer and the brain, the spirit might be analogous to a computer program, which might remain somehow and somewhere after death.  My criticism (as I thought I'd explained previously), is that this analogy fails on two main counts, firstly that the brain doesn't have anything like a program, and secondly that a program running in a computer doesn't remain behind when the computer is switched off. So the brain isn't like a computer in the way required for your analogy to work, and a computer doesn't work in the way the analogy requires (with the caveats mentioned in my last post).

I also touched on another problem with the computer program analogy in this respect, that a program runs on a physical computer, and if, for the sake of argument, we ignore the two problems above and assume the brain does have something like a program that does persist after death, then it would need another physical brain to 'run' on. A disembodied entity would, by definition, not have a physical brain to run the proposed program.

I've pointed out the grounds on which I suggest the analogy fails, but rather than address the problems I raised, you question my understanding of analogy; this the ad hominem fallacy. Address the argument, not the arguer.

[dlorde]

Haunting, poltering, wailing, clanking chains, putting crazy ideas into people's heads ....

That isn't work being done in the sense a physicist uses the term. Please be more precise next time. When explaining how work is being done physicists don't give examples of a source of energy. They describe specific forces acting over a specific path.(e.g. for the work done on a point particle we calculate a line integral).

Any physical interaction involves forces acting. Poltering (poltergeists moving objects) requires a force to be exerted to move the objects. Wailing and clanking require force to induce vibrations in air molecules to make sound, even putting crazy ideas in people's heads require some interaction with the physical world that ultimately affects the operation of the brain (with the exception of hallucinations, where the work is of internal origin).

So work is being done precisely in the sense a physicist uses the term.

Light coming from outside, through my window and into my room is a method of increasing the energy content of my room. In such a case no work is being done.

Work is done converting some of the light energy to heat by increasing average velocity of the gas molecules in the room, and so-on.

I wanted to give you an example of something which was universally assumed to not presently exist in nature alive which was proven false. You mean to say that you didn’t catch that? I’ll try to be more clear in the future.

I was simply pointing out that it isn't a comparable situation. We had incontrovertible evidence coelocanths were real and had existed. They were assumed not to be contemporary because such 'living fossils' are exceptional (though there are other examples). We have no such evidence for ghosts, only stories; no reasonable grounds to assume they exist or have ever existed, any more than goblins, pixies, and the tooth fairy.

One aspect of the mind is information. There exist forms of information that has no material medium. It's not even made of atoms. One example that I know of is the information contained in a radio wave.

A radio wave is electromagnetic. It consists of photons. Photons are material in a physical sense, although they don't need a material medium to propagate through.

A well-known physicist, Henry Stapp, proposed a while back that the mind is a quantum effect. I don't know the current status of that idea.

Penrose, Hammeroff, and others have proposed similar ideas. They're generally not accepted by the neurophysics community partly because there is no evidence to support them, partly because there are physical problems with them (especially decoherence), and partly because they don't actually explain the mind or consciousness any better than conventional hypotheses.

If ghosts really exists and are humans whose minds became disembodied then perhaps one way that might conceivably occur might be for that mind to manifest itself as a quantum state impressed onto a highly complex field, which then evolves according to the principles of quantum theory.

Before you hypothesise about mechanisms, you must first establish that disembodied spirits exist. I agree that people believe they've observed ghosts, but that doesn't mean they're physically real, or that they're disembodied spirits.

There are other kinds of fields in physics that you may never have heard of which can be found in the physics literature. The ones you’ve probably heard of are the gravitational field, the electromagnetic field and the gravitational field, You may not have heard of the Higgs field and the inflaton field.

Please, enough of the ad-homs; I'm well aware of the Higgs field and the inflaton field.

I'd rather you address the arguments & questions.

The brain might die and leave behind the program, i.e. us.  Perhaps there is a structure which we are unable to interact with into which our "program" resides after death.

What you did was to completely ignore the part that I've underlined here and response to something I assumed that you and everyone else who reads this is assumed to know.

OK, assuming by 'program' you mean something other than a computer program analogue, what kind of structure do you have in mind? what reason do you have to suspect such a 'structure' might exist? what might it consist of? why do you suggest we would we be unable to interact with it?  if we can't interact, then how can it affect us? what might this 'program' consist of? why do you think it might exist?

These signals have an electromagnetic component to them. I.e. the brain radiates EM waves (also called brain waves). Those EM waves leave an imprint on the universe by existing in space and time after they leave the brain.

The brain waves are the summed effect of billions of neural depolarisations travelling through the brain. They're barely strong enough to detect on the surface of the skull. They can give us a crude idea of gross brain activity, but there are much more informative means available, such as the various MRI and PET scanning techniques. What's your point?

If you’ve ruled out the existence of the soul and spirit then that’s fine by me. As for myself I don’t assume everything that has not been demonstrated to be true beyond all doubt to automatically to be wrong.

My view is that, despite extensive investigation for many years by many competent people, no reliable evidence has been found for them. There's no reasonable argument as to why they might exist, how they might have evolved, or any theoretical mechanism or reasonable argument to support them. As generally described, they are ill-defined, incoherent concepts with no physical or biological basis, and in my opinion, their existence would not only require entirely new physics, but would also probably violate fundamental physical laws. They explain nothing that cannot be explained more simply by the known imperfections and fallibilities of human perception, cognition, and memory. Therefore I'm as confident they don't exist outside people's imaginations as I am confident that gremlins, pixies and the tooth fairy don't exist.

Unlike you I'm willing to concede that there are things about the nature of conscience that we don’t know. Perhaps there is something to the mind beyond the nerve cells that we believe constitutes the physical embodiment of the mind. Please note that I'm not claiming that it does. All I'm saying is that I know that there are things the human race doesn't know yet and just perhaps the mind leaves something of itself behind when the physical brain dies.

You misrepresent me. I'm happy to agree there are things about the nature of consciousness that we don’t know. That's what makes it interesting. But the biology and physics are not entirely random, they have patterns and structure and follow rules. We know what the brain is made of, and how it functions, in considerable detail. There are lots of gaps, and missing detail, but what we know about it rules out huge swathes of irrelevant ideas, in the same way knowing the fundamentals of an automobile rules out the idea that it can fly, even if you don't know whether it runs on gasoline or electricity.

A man named Henry Stapp wrote about the mind as a quantum effect. I don't know the current status of that idea right now.

You already mentioned that.

Don't make the mistake that so many people in the world make by assuming that if we don't know about the existence of something then it doesn't exist.

I'm with Rumsfeld on this - there are known unknowns and unknown unknowns. But there are also patterns and rules to the workings of the universe that observation and the scientific method reveal that can make us certain beyond reasonable doubt that some things are not possible. My car won't fly. Russell's teapot isn't in orbit between Earth and Mars. It informs my opinion that ghosts and spirits are imaginary.

For some reason unknown to me you took my comment that some people have a theory about ghosts as me making a claim that there is a valid tested theory that  they exist.  Here's some advice fore you: In the future, if I don't see me say something then there's a good reason for it.

I took your use of 'theory' only to mean there was some structured rationale behind it, some theoretical basis. Is that not reasonable?

However, in general, if you use the word 'theory' in a science forum, people are going to assume you mean scientific theory. In the context, I questioned whether it was even a theory in the non-scientific meaning. A theory surely needs some structured argument.

Also please don't put words into my mouth like you did above..
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You took that very precisely worded statement and twisted it to mean something else. You read things into what I said and which were never there to begin with.

That's not me putting words into your mouth. That's you not being clear about what you meant. You may think you're being clear but it doesn't always read that way.

you  made the following false assertion

You claim that ghosts may be the disembodied consciousness of a deceased person, but provide no evidence or theoretical basis.

First off it is inaccurate to say "You claim ... may be ..." To make a claim is to make a definite statement about the way something is. One doesn't make a definite claim and then imply that it's not certain. In the second place I never made such a claim and here you imply that I did. That's called "putting words into my mouth."  I never made such a claim or assertion.

Yes, mea culpa; I've already apologised for that.

When you read my post you assumed it was written by a person, not a computer or an alien did you not?

No comment

People also have reasons for their assumptions that ghosts exist. Recall that I Said that a large percentage of scientists believe in God. A large percentage of that subset of scientists are Christians who believe the bible. A large percentage of that subset believes that the bible is literally true. In the Old Testament in the Bible King Saul writes of his discussion with the ghost of the Prophet Samuel (1 Samuel 28:11).

People believe a lot of things. It doesn't mean they're true.

You also seemed to imply that if ghosts exist that they could aliens or something else. You really must think that we just toss this stuff out there willy-nilly or you have made a very poor assumption of our scientific skills and knowledge base. In the future, before you make another comment of that nature regarding a term, I highly recommend that you look that term up in a dictionary. That's what I do and this is what I found that applies to this conversation

a disembodied soul; especially : the soul of a dead person believed to be an inhabitant of the unseen world or to appear to the living in bodily likeness

Now you're putting words in my mouth. Highlighting the lack of supporting evidence or argument for the 'theory' you proposed, I said, "I could equally counter that they're actually aliens, or entities from another dimension, or faeries, or they're just figments of the imagination. So you tell me - what's your evidence or theoretical basis for your particular claim? What makes it more reasonable than my suggestions?". In other words, what makes ghosts and/or spirits a better or more believable explanation than any old fiction, or my favoured explanation, that they're imaginary ?

Suppose a person sees something that has the appearance of a partially transparent human which looks like that persons dead relative. Then assuming that it used to be human is not an outrageous assumption. In fact one could even take that to be the definition of a ghost.

If the definition of a ghost is 'something that has the appearance of a partially transparent human which looks like that persons dead relative', then I'm happy to admit they exist. I have a ghost that fits that definition on a family photograph, caused when my (now deceased) uncle moved as it was taken. Now I think of it, I have childhood 'ghost' photograph of myself, where I used a self-timer to take my picture; you can see the chair through my body

What I have plenty of reason to doubt is that it has anything at all to do with spirits or ghosts as commonly understood.

Do you know of any reasonable argument for the 'theory' that ghosts or spirits exist (beyond the fact that some people think they're real)?

[Bored chemist]

If I put two protons and two electrons in a box then the box will be electrically neutral.
If I put two protons and one electron in a box then the box will have a net positive charge.
So, no matter what they do inside the box, even from the outside I can tell the difference between two atoms (neutral) and a proton+ an atom (overall + charge).

So the answer to the question is no.