Thoughts Unclassified

Climate Change: A Very Short Story

2007-02-09T01:32:00.000+05:30

Let us start with a very short story. In fact, I intend to confine myself to just this story in this post. We shall return to this story and its characters whenever the need shall be felt. Now, the story.

There were two neighbours P and S. P decided to run a machine for its private use. One effect of running this machine was to make P richer. The machine, however, also poisoned the air whenever it ran. Nobody knew of this polluting effect. But both P and S faced the adverse effects.

How did they mitigate these adverse effects? As we have already said, they did not know the causes of the pollution. So P, being rich, invested heavily in research on air masks, air filters, etc. and ultimately invented, owned and used them. S, on the other hand, being poorer could not afford the new gadgets and facilities. S, perhaps, was poorer because of not using the polluting machine. Since the machine created wealth, P continued to depend upon it. There was more pollution. P continued to invest a fraction of the wealth to overcome the adverse effects. Hollywood does not particularly attract me. Or else, I would not consider it very implausible that P ultimately began to inhabit Mars when the pollution became intolerable. (This, of course, would have to happen before the attack of the aliens, chimeras and monsters)

What about S? With little resources to spare after meeting the bare needs S could not benefit from the use of the mitigating inventions. The suffering of S increased.

Thus, the more P polluted, the more S suffered. P suffered too but depending upon the magnitude of the good and bad effects that running the machine had it was, perhaps, completely possible to mitigate the negatives. Even if otherwise, the bad effects of pollution on P were significantly retarded as compared to that on S.

Then P and S got serious about their conditions. So they studied the problem and discovered that the pollution came from the machines which were put to use by P in a far greater proportion than S.

This was a politically inconvenient conclusion. P would have to stop running the riches-cum-pollution generating machines. P would have to compensate S for all the suffering caused by it to S. And since their study had pointed to a persistence of the ill-effects for many years into the future even if the machines would be immediately banned, P would have to compensate S for many years into the future. That is all common-sense, fairness, justice or any name you like. P knew this. So P decided to disagree (as much as possible without appearing completely irrational) with the findings of the study.

Years passed. New data emerged. Better analyses was possible. And the conclusion was the same. Only, it was more certain.

Does it all appear familiar? Well, the story ends here.

Logic: The 'is-ought' problem

2005-07-04T23:37:00.000+05:30

A seemingly simple question:
Can we infer an ought statement from an is statement?

And one example of such derivation was given by amiya :

EXAMPLE
Premises: 1. John eats chocolates.
2. John does what he ought to do.

Conclusion: Therefore John ought to eat chocolates.

Neat indeed!
I appreciate the way the above example has been constructed.

However, if inference is being used in this question as in logic, then one should first state what logic is being used, what an is-statement is and what an ought-statement is.

First order logic, for example, does not have anything to do with the structure of statements except those introduced by its own connectives, quantifiers, inference rules etc.

Therefore, the discussion will not be meaningful until the terms involved in the question are defined. Or, at least, explained with some clarity.

Now, I will myself jump the gun. That is, I will add to this discussion without myself attempting what I have asked for (the definitions).

An ought-statement cannot be inferred unless there is an ought within the premises or in the rules of inference. This is, of course, obvious. Because, if the ought-clause is already there in a complex proposition, it may be possible to infer it in a valid way. But, if the premises do not contain either an implicit or an explicit ought-clause, there has to be a rule of inference that allows ought to be inferred from is.

Also, ought is about an imperative and is applicable where, seemingly, the opposite of what has been asserted as an ought is a likely course of action. On the face of it, a choice among various course of actions can be justified by inference only if the consequences or the circumstances related to choices can be arranged in some order of preference. This ordering is then a premise in our argument, and the inference would require, in addition to the aforesaid premise, another premise of the form: "The choice of action ought to be in accord with the most preferred item in the ordering (mentioned above)."

Or this last statement will be a rule of inferring the choice of action. But with this rule, we have a new species of logic. On this, I will say nothing further.

But, in ordinary english, let us be clear that the justification of a choice of action from is-statements has more to do with rationality than logic.

Inferences as to what a rational person would under the given is-premises itself involves a lot many unstated assumptions which implicitly depend upon some mutually agreed upon ordering of the kind mentioned above.

Mechanics: Are 'Newton's laws of motion' laws indeed?

2005-06-04T22:30:00.000+05:30

As schoolkids, and even afterwards, all of us have started our mechanics with the three 'Newton's laws of motion'. And, for them who ever scrutinized these laws, doubts arose. Doubts whether these are actually laws or mere definitions. In the following I will present the reasons for these doubts.

An equivalent statement of 'the first law' is - Every body, in absence of action of forces, moves with a constant velocity (rest being a special case). What difficulties, if any, arise from this statement? For this statement to be a law, one should be able to assert the following two facts independently. Firstly, it should be possible to distinguish the case that a body has a constant velocity from when it has not. Secondly, it should be possible to tell whether the body is being acted upon by some external force(s). Assuming that both these can be independently determined,the statement can be said to be a statement of law. This law would be true if we empirically discover that constant velocity indeed appears only in the absence of external forces. Otherwise, the law is falsified.

To determine the absence of force, it is essential to know certain characteristics of force with which to determine its absence/presence. But the very concept of force is not known prior to these laws. Moreover, without a clear prior definition, 'force' occurs in all the three laws. If, then, we depend upon these laws to know what force is, we are led to the conclusion that force is that which causes acceleration of the bodies it acts on. This conclusion can be derived from both the first and second laws. Then, if the absence of the force is determined by the absence of acceleration, the first law is a tautology. It is perhaps better to say that the 'first law' is itself the definition of force. However, the 'second law' says even more. It is therefore a better definition in which case the 'first law' is simply a special case of the second. But we should not forget that both these 'laws' are mere definition.

The second law however does assert that acceleration is of fundamental importance in writing the equations of motion of any system. The second law also prompts us to find a cause of the acceleration in a force which must necessarily depend upon the properties of the environment of the system and also upon the properties of the interaction of the system with the environment. Surely, one need not employ the fiction of force. The laws of motion can, of course, be written without such a notion. Although superfluous, it is harmless to call some terms of these equations by the name force.

The first two laws are perhaps a definition of an 'independent system'. A system in which the total dp/dt = 0 is said to be an independent system. As a result of this definition, whenever dp/dt != 0 the system is said to be independent, otherwise it is being acted on by external 'forces'.
Let us now assume that we are given an independent system which can be considered as sum of two distinctly identifiable systems. If p1 and p2 are the momenta associated with two parts of the system, and if p is the momentum of the whole given system then p = p1 + p2, or dp/dt = dp1/dt + dp2/dt = 0 (since we are given an independent system by assumption). Therefore, dp1/dt = - dp2/dt. This, as one can readily recognize, is 'the third law'. If we regard a system as made of three parts or more rather than two, we would have other laws like the third. For example, for n parts the law would look like dp1/dt + dp2/dt + ... + dpn/dt = 0. Given that p = p1 + p2 + ... + pn, we can state that dp/dt = 0 which, in turn, is true by assumption and therefore the source of the equation with n terms.

As to how we assert that the momentum of a system is equal to the sum of momenta of the parts of that system, the answer is in kinematics. The vector sum of momenta follows from the possibility of the vector sum of displacements and its derivatives. This, we shall not pursue here.
From the above, it will become evident that 'Newton's three laws' are not laws at all. Apart from asserting the importance of the time derivative of momentum, they merely define an independent system. It remains to examine whether there are any independent systems at all.

Metaphysics: Existence of Unobserved Events

2005-03-26T01:01:00.000+05:30

Someone wrote:
"Just because we hear an alarm clock when we are in hearing distance of it doesnt mean that it still makes a noise when we can't hear it."
________________
That is a neat and sound argument. The question is whether it is correct to infer/hypothesize the existence/occurence of events that are not observed. Let us call such inferences by the name "inference X".

Let us begin with asking why we infer that events have happened/will happen even in the absence of observation. Irrespective of the nature of the real world, or whether there is any reality beyond our perceptions, etc. the inference of events without observation yields a simple and fairly consistent picture/theory of the world (of reality/of perceptions?) making it easy for us to comprehend and understand it. To this most of us will agree. Thus, we know the usefulness of the inference X. And, therefore, inference X can be used until it is falsified even though it may not be verifiable.

Now, having admitted the utility of inference X, are these inferences correct? Clearly, the answer will depend upon the verification of the inferred event. Since the observer has not directly perceived the event and only inferred it, he/she must depend upon other means of verifying. Then we are led to the question: what are the other sources (i.e., other than one's own perceiving something) on which one can rely on as an evidence to the occurence of some event ?

I will not attempt a reply to this question. Because an answer to it will vary according to what sources we trust? But let it be clear that holding perception of the event by oneself as a reliable evidence of the occurence of that event is questionable too. That is, I could just as well express the doubt: just because I hear an alarm clock does not mean that the alarm clock is making the noise. The doubt, as can be seen, will turn out to be important in case of observers with hearing aberrations.

However, in raising this doubt I am not merely thinking of some stray pathological cases. Philosophically, the doubt is even more important. The manner in which you resolve it determines the kind of picture/theory that you prefer to have about this universe. And the incorrectness of that theory will be determined if it leads to some incorrect fact (which in turn should be verified/falsified using the methods consistent with the theory being tested). Meanwhile, there is no denying the possibility of the existence of many competing theories. In some of these, the alarm clock will sound when you can't hear it. In others, it won't.

General: Pragmatic Ignorance

2005-02-26T13:16:00.000+05:30

They say that "ignorance is bliss. The more we learn, the more we know there's more to learn. The more we seek and obtain knowledge, the more unsure we are about the knowledge we've hitherto gathered. Is there any point to our hopeless search for wisdom? Aren't careless people happier? Shouldn't happiness be the benchmark from which we value actions?"

I guess these thoughts must have crossed the minds of most of us. I am not very sure what exactly is meant by "the search for wisdom". Philosophy, or for that matter any search for truth is frustrating the moment we realize that the search is an unending quest. That is, we are always on uncertain footing, and unsure. And the more we know, the more there seems to be to know. If our search is for certainties, some kind of final truths then we must restrict ourselves to tautologies. Anything else will be uncertain. This realization is the first meaningful realization that any philosopher or scientist or a human being should have before he/she sets on the path of any enquiry.

Thus, if we are looking for certainties, we are on a wild goose chase. But if we realize that ours is going to be an unending quest, the frustration of pursuing a "lost cause" will not set in.

The pleasure of philosophy is not in discovering, but in the process of discovery. Other uses may exist, and they are perhaps very important too. But I think that the pleasure of philosophizing or doing science comes from pursuing a path even though one knows that it has no destination. We have our own wits to tell us where, on this path, we may pause to pursue again or even stop. But every stop is merely a convenient resting place. Despite there being directions in which to pursue, there is simply no destination to aim for. So if one loves travelling along this road, then one loves it despite knowing that the journey will not end at a destination. The best one can hope for is to build a comfortable resting place (a theory, a model, etc.) at the end of one's journey.

For those who find such pursuit hopeless, they are perhaps looking for more than just travelling. Before starting they should be clear as to what they expect. For those who find it useless, it is possible to enumerate some uses and advantages of the journey. Regarding "ignorance is bliss" mantra, I think there are some people who cannot manage to remain ignorant even if they think that it leads to bliss. The curiosity embedded into their minds perhaps leads them to attempt discovering and unravelling mysteries. These are the people who will philosophize even if they suffer. For the others, they can judge whether they are prepared to walking down unending roads, many of which are without any signposts.

Let us, however, remember that a mind once exposed to philosophy cannot get back to starting point provided it feels the philosophy. To make this statement clear, I will give an example. If you philosophize on time and space, you can do from the point of view of a person sitting with a paper and pencil and trying to arrive at a consistent model in order to solve a puzzle in a manner similar to that of solving puzzles from the leisure section of a Sunday newspaper. This is philosophy but without having felt it. But when one attempts the same solution because of the bewilderment that this world, this universe poses then one feels the philosophy. I have given this example to make the following statement:

Those who are amazed by this world, and then "feel" philosophy have no hope of returning to bliss that comes from ignorance even if philosophizing is painful to them.

Logic: Affirming the Consequent

2005-02-03T13:25:00.000+05:30

I will begin with a slightly edited quote from a discussion on modus ponens or affirming the consequent from www.ephilosopher.com.

------Start of Quote---------

ARGUMENT #1 (modus ponens):
Where A is any well-formed formula (WFF) and B is any WFF:
1) If A then B
2) A
3) Therefore, B

ARGUMENT #2 (affirming the consequent):
Where A is any WFF and B is any WFF:
1) If A then B
2) B
3) Therefore, A

Suppose, however, that A and B are the same WFF-- call it "S". The resulting argument looks like this:

ARGUMENT #3:

1) If S then S
2) S
3) Therefore, S

What is the best description of argument #3? Is it modus ponens, affirming the consequent, or something else?

----End of Quote----

Interesting question! First let me say something about the question itself.
It is obvious to everyone that arguments #1(modus ponens) and #2 (affirming the consequent) quoted above are templates wherein A and B stand for any two (not necessarily distinct) WFF. Determining whether argument #3 is derived from argument #1 or argument #2 is important only because in the former case it must be correct (because arg #1 is correct) but in the latter case it must be wrong (because arg #2 is wrong). Had both argument #1 and #2 been correct, the question would have been neither important nor interesting.

Argument #3 quoted above fits both the templates when A = B. And, therefore, the puzzle whether the third form of argument has been derived from the first or the second template cannot be resolved in favour of just one of these arguments. Since, resolving is required let us follow the following attempts which I will call solutions:

Solution 1: If one adds the restriction in argument #1 and argument #2 that A and B cannot be the same WFF then argument 3 is clearly something else. And then argument #3 could be called a simple tautology. In fact, as stated already nobody would bother to offer such an argument.

Solution 2,3: Similarly, the restriction mentioned above could be applied to just one of the arguments #1 or #2 and then argument #3 would be derivable from just one argument (the one to which the restriction has not been applied). In these cases too, the problem would be resolved.

However, I do not favour these solutions unless there are other grounds to add such restrictions too. Let us examine these grounds if they exist.

In so far as argument #3 is derivable from modus ponens, no problem arises. That is so because modus ponens is correct whether A=B or not. So we will assert that argument #3 is modus ponens.

What about the argument #2? Clearly, it is a wrong form of argument only when "B does not imply A". Then, any substitution of A and B with some WFF such that "B implies A" will allow the inference A and the argument will look like affirming the consequent. I say "look like" because the hidden "B implies A" has been employed. It surely may happen that "B implies A" takes the same form as WFF (1) or WFF(2) of the argument #3. With this in mind, I propose the following solution:

Solution Final:
Argument #2 should be modified as follows to be true in general:

--------------------
Where A is any WFF and B is any WFF such that "B does not imply A":

ARGUMENT #2 (affirming the consequent)

1) If A then B
2) B
3) Therefore, A
--------------------
With this modification, argument #3 is modus ponens.

Logic: The Wittgenstein problem

2005-01-12T13:50:00.000+05:30

This is a problem which should have puzzled every person who has ever ventured into philosophy of any flavour.

The following is a slightly edited and altered text quoted from a post by Bollinger, which he calls The Wittgenstein problem.

"The central questions are:

1. How do we manage to coherently label the world into particular objects through the use of language?

2. (a) And if labelling is a purely conscious process then why can't I explain how I manage this labelling?
(b) In other words how can I not know something I am doing consciously?

This I call the Wittgenstein problem in honour of the great Austrian thinker who posed these types of questions in his work 'Philosophical investigations'."

(Before beginning, I must congratulate "Bollinger" at www.ephilosopher.com for a very clear statement of the questions.)

These are two beautiful questions that have always puzzled me. And I must admit that I am in no position to give a definite answer to them. I do agree that we, in general, manage to coherently label the objects we observe; and that we have difficulty explaining how we manage to do this labelling.

I think I encountered this problem quite a few years back when I started wondering about what to call a living thing. That was during my schooldays when I had started pondering over the subject of artificial intelligence and artificial life. To be able to create what could be termed living or to even explain the origin of life, one must have a clear conception of what a living thing is. Such a concept or definition I have failed to arrive at.

Similarly, one could consider even the simpler objects and still stumble upon the same hurdle. To define X as a class of all the objects that are labelled X serves no great purpose. Because this definition would not guide you whether a new object that you come across could be labelled as X or not. Also, such a definition will keep getting revised each time a new object (i.e., one that is not already in the class) is labelled X.

I will not go into detail of how the difficulty of explaining the method of labelling arises. Anybody who has given some thought to this subject will easily understand this and raise the above questions. However, a clearer idea of the problem can be obtained by reading the first post in the discussion on The Wittgenstein problem.

Let me repeat that I am not suggesting a solution. I will try to show one way in which it is possible for us to coherently label without managing to explain how.

Consider a very complex neural network N1 that is designed to be able to classify things which it may be able to do quite satisfactorily. Let N1 also have a feedback mechanism by which it can occasionally tell that its classification was wrong and, at times, it can make corrections too. But N1 is not designed to output the exact configuration of weights that allows it to do the classification. The result is that N1 can coherently classify the objects (and hence, label them) without being able to explain how it does so.

What are the lessons one can draw from N1? If our brains and the associated paraphernalia are designed/wired/evolved to coherently label things (among other faculties) but not to bother about the design then it explains how the two questions arise. The N1 example has been kept very simple to illustrate the essential elements only. Better examples can be formed without adding much.

However, N1 misses one part of the question completely. That is, "if labelling things is a conscious exercise, how can one not know how I label things".

The introduction of the term "conscious" (and its related forms) into the question necessitates understanding consciousness and its capabilities.

Consider a very complex neural network N-omega (many generations higher than N1) which can, of course, classify and label objects. N-omega can also do some maths. But what distinguishes N-omega from other generations of neural networks is that it also asserts an identity in its communication with its human users. Assume that this assertion of identity results due to its high level of complexity (I am not sure if that is possible).

It then follows from the design of N-omega that it can label things, and it asserts that it is conscious when it does such labelling. But it may still not know how its consciousness works. To be conscious of a process is quite different from understanding that process.

In stating all this I am not saying that this is how the brain works and hence the questions. What I am saying is that such questions can co-exist in certain scenarios, one of which is rudimentarily shown above.
----------------------------------
Conclusion
----------------------------------
1. The ability to coherently label things could be a result, among other things, of
(a) knowing explicitly the criteria to be followed in doing so and then using the classifying apparatus (brain, neural network, computer etc.) to algorithmically (or otherwise) put the object to the test of the given criteria, or
(b) only the structure and complexity of the classifying apparatus.

2. If the criteria is explicit, there is no difficulty in explaining how the coherent labelling is possible. But, if the labelling is a result of only the structure and complexity of the apparatus then it will be difficult to tell how the labelling is managed so coherently. The degree of difficulty should increase with the complexity. As you can see, this difficulty has nothing to do with being conscious of the process or otherwise.

Also, to be conscious of a process is quite different from understanding that process. Therefore, the only knowledge that can be inferred from being conscious of a process is the knowledge that one is conscious of that process. Being conscious alone does not imply any further knowledge about that process.
----------------------------------

Logic: Do fictional characters exist?

2005-01-11T15:11:00.000+05:30

Recently, I was confronted with a question that can be briefly phrased as follows-:

--------Question
how to deal with things like Santa and purple cows in logic. If they do not exist, then how are we supposed to represent them in predicate logic.
--------end of Question

The following is an attempt at an answer.

There would be no problem here if we did not insist upon the "existence" of all entities for them to be true, etc. When I say that "the number 2461 exists", the existence implied is different from that which is implied by my saying that "in my pocket, a pencil exists". For the latter existence, the verification has to be done empirically in the spacetime of my pocket. But the existence of the number 2461 or any other is a matter of pure logic. That is, if 2461 ia an member of the class of numbers, then one might say it exists. This kind of usage is uncommon but I have introduced here with a purpose. Consider the following:

---------ILLUSTRATION 1:

X is an entity satisfying the following:
1. X belongs to the class A.
2. X belongs to the class B.

Then, does X exist? The answer can be given by looking for a member of the class A which is also a member of the class B. If such a member can be found then X exists, else it does not.

---------end of ILLUSTRATION 1

If you agree with the above illustration, then we can come to the question of the entity called Santa. To know what is Santa, we need to know the complete list of those attributes which when satisfied by an entity, the entity can be said to be Santa. Call this list of properties/attributes P. Then, to verify whether Santa exists or not one just has to look for an object that satisfies all those properties. If one finds any, Santa exists; otherwise, he does not.

The problem arises from the fact that when listing the attributes in P, one generally leaves a lot to be assumed. Suppose P included the attribute f: "Santa belongs to the class of characters in fictions" along with the other attributes, then depending upon what those other attributes are Santa may , or may not, exist. But if P included the attribute f': "Santa is not a fictional character" then one would probably assume that Santa's verification would require to look for him in the physical world.

To summarize the above, from the point of view of logic it is unnecessary to maintain a difference between entities depending upon whether they satisfy the attribute f ("is a fictional character") or its opposite f' ("is not a fictional character"). Therefore, there appears to be no reason why the fictional characters (that do not exist in the physical world) should be treated any differently from others. Also, they would not require a different representation in predicate logic unless the representation is unnecessarily made dependent upon the attribute f.

Fictional characters exist on the same footing as the concepts, ideas, etc. exist. The difference between fictional and physical begins to show when one moves from the world of pure logic to that of verification of existence. The verification could end up being entirely within logic as in the case of contradictions and tautologies, or it could cross the boundary of logic into the empirical sciences.

Science: Quantum Immortality

2005-01-08T15:34:00.000+05:30

First, let us consider the many-worlds interpretation of quantum mechanics because this is essential to understanding the concept of quantum immortality.

In what follows I will presume that you have a basic acquaintance to the concepts of quantum mechanics.

In the many-worlds interpretation of quantum mechanics, the wave function collapse mechanism is substituted by a splitting of the observed system - each new branch corresponding to one possibility. Suppose the wave function of a system S is the superposition of two measurable states A and B. According to the Copenhagen interpretation, on measurement the wave function collapses and the system evolves from being in a mixed state to the measured state. In the many-worlds interpretation, the system splits into two: one yielding the value A and the other B. If we apply this interpretation to all the systems i.e., to our world itself then the this universe is continuously splitting and branching so that all quantum-theoretically possible combinations of measurements are realized. Thus the splitting leads to a tree structure in which following one line of branches from the root yields one possible world. One may also state that mixed quantum mechanical states result from superposition of more than one world.

Secondly, let us come to the idea of Quantum Immortality.

The many-worlds interpretation implies that any likely event, however improbable, does get realized in some world. Now imagine the process by which a man X is led to his death dependent upon factors each of which may or may not happen. Note that even if one of the contributing factors to death is such that the quantum theory predicts it with a 100% probability then the death is a must no matter how and how many time the observer's world splits and branches. Otherwise, of course, there will be worlds in which none of the factors contributing to death may happen. Consequently, these will be the worlds in which X will not die. All the worlds being considered together, X will continue to live in some worlds and thus X will be immortal.

But is this really the sense in which a living being can be said to be immortal? This leads us to the third part of our argument.

Assuming that we understand the meaning of consciousness, it is not as if when the man dies in one world his consciousness is transferred to another. Like all other attributes, consciousness too should split along with X as should his identity. On death, few worlds will inherit consciousness while others won't.

If the above assumptions hold (including absence of a 100% probable factor leading to death) then I (the first person) should also continue to live forever. But the "I" is also splitting. And the likelihood that the "I" that is writing all this is the same "I" that is immortal (or say, the "I" which will live for 1000 years) is just as much as the fraction of worlds in which this "I" is immortal (or, has a life span of 1000 years). To get an idea of this likelihood we can do our maths in this very world if we could calculate the probability of this "I" surviving forever (or for 1000 years). I have included this '1000 years' alternative so that you wouldn't at once assert impossibility of the referred event.

Maybe, one could argue, the probability of observing a 1000 year old man can be increased if we include in our survey all the men on the earth. Yes, the likelihood will increase roughly six billion times but how significant that increase will be depends upon the result that we arrive at (which, for all you know, could be too low to expect to yield a positive outcome in an experiment. Thus it must be extremely unlikely for any of the experiments to witness a 1000-year old man.

We have so far assumed that the identities across the various worlds do not interact. Suppose, in some way, they did. In other words, suppose the various worlds interfere with each other. Then, for any given man, in the long run, we should expect a certain concoction of many of his dead versions and a very small fraction (relative to the number of the dead versions) of his immortal or near-immortal versions. Although I have not given due thought to this aspect I think the identity as we assert it in terms of "I" cannot be a superposition of the dead and immortal "I".

I will try to explain why I think so. Call it the splitting of the world into more than one or the collapse of the wave function, the end result is that you, as the observer capable of asserting an identity, finally record only one possible state of a system even though others were likely. This record becomes a part of your history. The other possibilities which were potential until the measurement had occured do not become history. At least, not in your world. If these possibilities are part of the records in other worlds, then those other worlds also have a different copy of "you" than the one in this world. Since you are unable to see those other possibilities as interfering with your records; and also the same quantum theory that leads you to hypothesize the other worlds gives you no clue as to their existence, I believe that the various worlds, if they exist, do not interfere. Thus there cannot be a trans-world identity of an individual. As a result, few of your copies (formed as a result of splitting of the world) would be immortal, but the majority will not be. Whether you are immortal or not depends upon which particular copy you are.

Let us remember that the idea of quantum immortality makes sense only if all your copies can somehow interact or interfere or superpose etc. (choose your verb) and the resultant "you" carries a single consciousness (whatever that means) that spans across the many worlds.

I hope the above is useful in clarifying the ideas and issues related to quantum immortality.