81 replies to this topic

[N.T.M.]

This might seem a little off topic, but I think it’s appropriate to post this here.

 

So I recently came across the term “quantum archeology.” I didn’t know what it meant at the time, but apparently it’s the idea that no information is lost with the progression of time, so, given enough computing power, it would be theoretically possible to extrapolate backwards and “resurrect” people; a sort of reverse determinism I guess. First off, if this definition wrong, please let me know. I did about one minute of research. 

 

My question here is about the assumption that no information is lost. Is this correct? It makes sense that you could in theory extrapolate forward in time, but backwards? I asked myself if, in principle, that’s even possible, and the analogy I came up with was a non-injective function. The sine function, for instance, is periodic. Each input is unambiguously mapped to a single output, but because it’s periodic, you can’t determine a specific input value from a given output. Intuitively, it seems like this analogy would hold in the universe too, in which case while it would be possible to extrapolate forward (the very definition of determinism), the reverse would not be true—i.e., information is lost.

 

Does anybody know if this is correct? Or does determinism go both ways? 

[Hip]

My understanding is that quantum information cannot be destroyed, but it can be transformed, provided it is done in a reversible way (ie, there is an undo button).

 

Perhaps the best way to explain this is via computer software concepts: If you are familiar with software programming on a classical computer (our everyday computers), you will know that any variable you use within the software, can at any time be deleted, or set to zero, or set any other value, during the running of the software. 

 

So for example, if in our software program we have a variable called X, and X is currently equal to 10, you can write some code in the software to set X to zero, or set it to say 12345. When you set X to 0, you lose the original information that was previously contained in X, in this case, the value of 10. And there is no way of getting that value back again. So in a classical computer, you can totally destroy information in this way: you can overwrite the value of X with a new value, and the old value is lost forever.

 

However, if you are programming for a quantum computer, it is physically impossible in the quantum world to overwrite the value of X with a new value, because that would be destroying the original information, which is forbidden in quantum mechanics. Irreversibly destroying information is against the laws of quantum physics, and such destruction of information cannot be done.

 

What you can do, though, in quantum computer programming is to perform reversible actions on the variable X. So for example, you can add 1 to X, so that it becomes 11. This action of addition is allowed in a quantum computer, because adding to the number X is reversible: the action can be undone, simply by subtracting the same number from X, ie, subtracting 1 from X, which then brings you back to the original value of X which was 10. 

 

 

So in this way, information in the quantum world can be transformed in a reversible manner: you can transform any information, provided that transformation is reversible, and will get you back to the original information if you reverse what you did. But information in the quantum world can never be deleted. 

 

 

 

Edited by Hip, 04 January 2017 - 07:02 AM.

[Danail Bulgaria]

Guys you both look at the values only as values, you forget to follow backwards the laws, that modify these values.

 

E.g. a PC software can make a variable namedX. Then it may place the number 10 in it. And it can make X = 0, but if you research the rules (THE SOFTWARE) backwards, instructio by instruction, you will get the initial value of X.

[platypus]

Since part of the "quantum information" is flying away from us as particles at close to the speed of light, the question is academic as long as we don't have a "sensor-wall" or equivalent that will eventually catch it. If someone already build such sensors at the edge of spacetime, humans certainly didn't. 

[N.T.M.]

Irreversibly destroying information is against the laws of quantum physics, and such destruction of information cannot be done.

 

This answers my question. I've studied Newtonian physics and electromagnetism, but I know almost nothing about quantum mechanics. 

 

 

Since part of the "quantum information" is flying away from us as particles at close to the speed of light, the question is academic as long as we don't have a "sensor-wall" or equivalent that will eventually catch it. If someone already build such sensors at the edge of spacetime, humans certainly didn't.  

 

That's true. But I still find it very interesting to learn that, in principle, this can be done (resurrecting people by extrapolating backwards in time).

Edited by N.T.M., 04 January 2017 - 08:24 PM.

[Hip]

For me, the more interesting question is how the indestructible nature of quantum information relates to the concept of a soul. If you subscribe to quantum theories of consciousness, then all human conscious experiences are underpinned in the brain by quantum mechanics, and every conscious life experience you have is written in quantum bits of information, in a quantum state in your brain — bits of information which cannot ever be destroyed.

 

So this certainly provides a framework by which we could approach a scientific understanding of the concept of a soul. Those conscious life experiences you have, which are encoded in quantum bits, had can never be erased or deleted, so they will certainly continue to exist after death; but they may be transformed by the reversible processes described above. So the soul and the quantum information it contains may continue to exist after death, but may be transmogrified — because quantum information cannot be destroyed, but can be altered by non-destructive reversible processes. So the soul may persist after death, but the information it contains may continue to evolve or transform, and generally continue to interact with the rest of the universe.

 

You also have in quantum mechanics the phenomenon of quantum entanglement, whereby two quantum systems are invisibly entangled over distances of space, or over distances of time. This means that the quantum state in your physical brain may be non-locally distributed to other parts of the universe, with links that transcend space and time, in some holographic-type manner. So the life experiences that you have amassed in your brain's quantum systems may not just exist locally in your physical brain, but could be distributed across the universe, and may even exist outside of space and time.

 

Quantum entanglement is not well understood at present, but I read some recent articles about new theories that propose quantum entanglement could be more fundamental that space and time themselves: the idea (which is well beyond my ability to understand mathematically) is that quantum entanglement creates the very fabric or scaffolding of spacetime. So quantum entanglement in this sense exists outside of space and time.

 

 

Edited by Hip, 04 January 2017 - 09:58 PM.

[N.T.M.]

For me, the more interesting question is how the indestructible nature of quantum information relates to the concept of a soul. If you subscribe to quantum theories of consciousness, then all human conscious experiences are underpinned in the brain by quantum mechanics, and every conscious life experience you have is written in quantum bits of information, in a quantum state in your brain — bits of information which cannot ever be destroyed.

 

So this certainly provides a framework by which we could approach a scientific understanding of the concept of a soul. Those conscious life experiences you have, which are encoded in quantum bits, had can never be erased or deleted, so they will certainly continue to exist after death; but they may be transformed by the reversible processes described above. So the soul and the quantum information it contains may exist after death, but may be transmogrified — because quantum information cannot be destroyed, but can be altered by non-destructive reversible processes. So the soul may exist after death, but the information it contains may continue to evolve or transform.

 

You also have in quantum mechanics the phenomenon of quantum entanglement, whereby two quantum systems are invisibly entangled over distances of space, or over distances of time. This means that the quantum state in your physical brain may be non-locally distributed to other parts of the universe, with links that transcend space and time, in some holographic-type manner. So the life experiences that you have amassed in your brain's quantum systems may not just exist locally in your physical brain, but could be distributed across the universe, and may even exist outside of space and time.

 

Quantum entanglement is not well understood at present, but I read some recent articles about new theories that propose quantum entanglement could be more fundamental that space and time themselves: the idea (which is well beyond my ability to understand mathematically) is that quantum entanglement creates the very fabric or scaffolding of spacetime. So quantum entanglement in this sense exists outside of space and time.

 

That's fascinating to consider, and strangely comforting, although I don't like the term "soul" because it connotes dualism. I plan to study quantum mechanics in the future, but unfortunately it's a ways out. I'm just taking engineering courses for now. Thinking about this, though, is making me curious about the prerequisites for an introductory course in quantum mechanics. 

 

*edit* So I looked it up, and the class is called Physics 421. Unfortunately, I have two unmet prerequisites: Physics 182 (I'm pretty sure this is "modern physics." It's the class directly following electromagnetism.) and Physics 301 (mathematical methods for physics). 

Edited by N.T.M., 04 January 2017 - 10:11 PM.

[platypus]

That's true. Buth I still find it very interesting to learn that, in principle, this can be done (resurrecting people by extrapolating backwards in time).

Debatable, as quantum mechanics appears to have a real random component in it. Also deterministic chaos and sensitivity on initial state ensures that infinitesimal errors will grow to very large ones. 

[Hip]

That's fascinating to consider, and strangely comforting, although I don't like the term "soul" because it connotes dualism.

 

But mind-matter dualism may well exist: don't forget that although humans have consciousness, which is assumed by some to be underpinned by quantum states in the brain (the brain thus containing a quantum computer), the brain also has many aspects of its nervous system circuitry which are non-conscious, and probably function via ordinary classical physics (and this part of the brain would be an ordinary classical computer). The brain's control of heart rate is one example of a non-conscious process that probably runs on the classical computer part of the brain, not the quantum computer part.

 

Information that is processed in the classical computer part of the brain is not indestructible, unlike the information processed in the quantum computer part, so these classical computer bits of information will be destroyed when the body is gone. But the quantum computer bits of information in the brain are indestructible. 

 

So in that sense, there is some dualism going on, because of this fundamental difference between classical bits of information and quantum bits of information. 

 

In the future, when hopefully we will have a better understanding of both consciousness and quantum mechanics, we might discover that what we today refer to as "mind" is simply the world of quantum information, and what we refer to as "matter" is the world of classical information. I think it will likely turn out to be something along those lines. 

Edited by Hip, 04 January 2017 - 10:41 PM.

[Danail Bulgaria]

In my oppinion nothing is absolutely random.

The absence of randomness is in the base of the causality.

Each event is being caused by something. 

First is the cause, and then the event. Never is the opposite - first the event, and then the cause. 

 

What seems to be random is actually something for which we don't know all of the factors involved. 

 

Perhaps you know, that each computer can produce random numbers. What you don't know,is that these random numbers are produced by a formula based on the clock of the computer. So it is not absolutely random either. 

[shadowhawk]

Good point.  Here is another problem.  http://www.ideacente...ails.php/id/832

 

 

[N.T.M.]

In my oppinion nothing is absolutely random.

The absence of randomness is in the base of the causality.

Each event is being caused by something. 

First is the cause, and then the event. Never is the opposite - first the event, and then the cause. 

 

What seems to be random is actually something for which we don't know all of the factors involved. 

 

Perhaps you know, that each computer can produce random numbers. What you don't know,is that these random numbers are produced by a formula based on the clock of the computer. So it is not absolutely random either. 

 

As I understand it, a truly random number generator has never been made. Also, I do recall seeing a lecture where a physicist said that everything, including quantum mechanics, is deterministic. I think most people here wouldn't argue that. My original question, though, was regarding whether the determinism in the universe is bidirectional (and Hip said that it is).

 

To platypus: 

 

I believe you're referring to chaos theory. And as I said above, I don't think that quantum mechanics does have any truly random component to it (at least that's what I've heard).

 

 

 

That's fascinating to consider, and strangely comforting, although I don't like the term "soul" because it connotes dualism.

 

But mind-matter dualism may well exist: don't forget that although humans have consciousness, which is assumed by some to be underpinned by quantum states in the brain (the brain thus containing a quantum computer), the brain also has many aspects of its nervous system circuitry which are non-conscious, and probably function via ordinary classical physics (and this part of the brain would be an ordinary classical computer). The brain's control of heart rate is one example of a non-conscious process that probably runs on the classical computer part of the brain, not the quantum computer part.

 

Information that is processed in the classical computer part of the brain is not indestructible, unlike the information processed in the quantum computer part, so these classical computer bits of information will be destroyed when the body is gone. But the quantum computer bits of information in the brain are indestructible. 

 

So in that sense, there is some dualism going on, because of this fundamental difference between classical bits of information and quantum bits of information. 

 

In the future, when hopefully we will have a better understanding of both consciousness and quantum mechanics, we might discover that what we today refer to as "mind" is simply the world of quantum information, and what we refer to as "matter" is the world of classical information. I think it will likely turn out to be something along those lines. 

 

 

I don't know enough about quantum mechanics to argue one way or the other here. I can see how things might work out if you modify your definition of the soul, but I'm very skeptical about how some information might be lost and other information retained.

 

*edit* (Apparently there's a limited number of quotes that I can use.)

 

To shadowhawk: 

 

You'll have to be more specific. What specific information from that source causes a problem? 

Edited by N.T.M., 05 January 2017 - 01:42 AM.

[Hip]

I don't know enough about quantum mechanics to argue one way or the other here. I can see how things might work out if you modify your definition of the soul, but I'm very skeptical about how some information might be lost and other information retained.

 

For the purpose of this discussion, we could define the "soul" as any information from an individual's brain or mind that survives death of the body in some way, even if the body is turned to ashes.

 

 

But regarding reversibility, and running the movie backwards to get back to an earlier time: there is fundamental difference between what physicists call the classical world (which is our normal everyday physical reality), and the quantum world which underpins the classical world.

 

We know that the classical world is not time reversible. The usual illustration of this is to imagine a short movie of an egg falling off a table and breaking on the floor; if we were now to run this movie backwards, you depict something that never, ever happens in reality: you never get a broken egg spontaneously reforming itself into a whole egg. 

 

So events in the classical world are generally not time reversible. The arrow of time points only in one direction in the classical world: forward. This is also connected to the second law of thermodynamics.

 

Things are very different in the quantum world: any event in the quantum world is always time reversible. In the quantum world, anything that is done, can also be undone again. So in a sense, in the quantum world, you have a bidirectional arrow of time. 

 

Nobody really understands why time behaves differently in these two worlds. But if you want to read a good popular science book about quantum mechanics which nicely covers the arrow of time, Roger Penrose's The Emperor's New Mind is an excellent choice. 

 

 

This reversibility of time I believe underpins why quantum information cannot be lost or deleted: because in the quantum world you can always wind the clock backwards, and return to an earlier state of the system.

Edited by Hip, 05 January 2017 - 05:09 AM.

[N.T.M.]

 

This reversibility of time I believe underpins why quantum information cannot be lost or deleted: because in the quantum world you can always wind the clock backwards, and return to an earlier state of the system.

 

 

Oh, I see. I was under the impression that the idea was just to extrapolate backwards from information in the present, not actually reverse something. These are fundamentally different. I understand that in classical physics you can't actually reverse anything (excluding reversible systems, which really only exist in theory), but if determinism were bidirectional you could in theory calculate a previous state.

[Danail Bulgaria]

The entire Universe is actually a huge information storage and the biggest supercomputer existing today. It holds the information for the position of each single atom, and the instructions - the set of rules, that govern everything, that is happening. And it instructs each one atom what ot do to the finiest detail at the scale of the entire Universe. If we learn to read the Universe, its software instruction by instruction, nothing is impossible.

 

You will be able to rewind in the both directions both in the case of classical and in the case of quantum world. In the classical you need energy to solve the second law of the thermodynamics. Where from you will get thet energy? Energy is never lost. It only transforms. You may use the transformed energy as a stored energy, that to triger the backwards processes by itsef.

[platypus]

In my oppinion nothing is absolutely random.

That is your opinion only. QM has an element of true randomness so you must entertain the possibility that universe allows for this. 

[platypus]

The entire Universe is actually a huge information storage and the biggest supercomputer existing today. It holds the information for the position of each single atom, and the instructions - the set of rules, that govern everything, that is happening. And it instructs each one atom what ot do to the finiest detail at the scale of the entire Universe. If we learn to read the Universe, its software instruction by instruction, nothing is impossible.

Perhaps the universe does not compute anything, and energy and matter behave according to relatively simple rules (which might include a component of true randomness). I think there might be a hammer&nail - effect working here: Us trouser-wearing monkeys think that universe must be "like a computer" or work with "deterministic rules" since we've had relatively good success utilizing those paradigms in the past few centuries. The universe, of course, is not limited by what monkeys can imagine at the present moment in time 

[Danail Bulgaria]

 

In my oppinion nothing is absolutely random.

That is your opinion only. QM has an element of true randomness so you must entertain the possibility that universe allows for this. 

 

 

There are two options - there is a true randomness, and there is no true randomness.

 

1. Thee is true randomness

To acheive a true randomness you have to violate the law of causality and achieve an effect before what caused that effect to even appear.

In this option you allow time travelling (in the back in time direction).

Using time travelling you may go back in time and observe the universe before the true random effect.

Knowing the situation before and after the random effect, you can calculate what happened.

Thus the random event can be predetermined.

You live in a calculatable world.

 

2. There is no true randomness.

Everything goes by rules, everyhing is calculatable backwards.

You live in a calculatable world.

 

Looks like check-mate to me.

[platypus]

 

There are two options - there is a true randomness, and there is no true randomness.

 

1. Thee is true randomness

To acheive a true randomness you have to violate the law of causality and achieve an effect before what caused that effect to even appear.

Does not follow. There could be systems/atoms/etc. that generate true randomness when triggered. This does not mean that cause and effect no longer function at all. 

[Danail Bulgaria]

If you have a cause, that made the effect, then that effect is not random - it has been caused. And there is a rule, that governs if the effect will be caused ot not.

That is not randomness.

 

The Universe can be computing in terms, that it follows its laws and rules. If it is so, then it is following an algorythm, just like your computer. Extremely difficult and maybe unsolvable from the people algorythm, but still an algorythm.

[platypus]

If you have a cause, that made the effect, then that effect is not random - it has been caused. And there is a rule, that governs if the effect will be caused ot not.

That is not randomness.

If there's an "operator" that produces true randomness, it means that when the operator is called it produces a truly random result. The result is random in the sense that identical initial conditions produce variable results. This is easy to imagine, and certainly a possibility that cannot be ruled out. 

Edited by platypus, 05 January 2017 - 02:31 PM.

[Danail Bulgaria]

That kind of randomness if exists is not frightening. We still can be resurreced.

 

It can be calculated by the end result. Factor A can make even1, event2 or event3. Currently we observe event2, so obviously the Factor A has chosen to do event2. Calculations continue with the presumption Factor A made event2.

 

In my modest experience everything random, that has been like that randomness, has turned out to follow natural laws, that have been unclear for me at the present time.

[shadowhawk]

What is interesting to me is the theory that in QM time is meaningless in a sense in that we are seeing it from our Classical World perspective and it appears we exist in a classical world which has originated in a QM world.  What has caused this?  It seems something is bringing order out of chaos.  Time goes in one direction.  Is there something timeless?  Does something control the direction of time.  One directional time is less than all directional time.  What exists is less than its source?

[platypus]

That kind of randomness if exists is not frightening. We still can be resurreced.

 

It can be calculated by the end result. Factor A can make even1, event2 or event3. Currently we observe event2, so obviously the Factor A has chosen to do event2. Calculations continue with the presumption Factor A made event2.

 

In my modest experience everything random, that has been like that randomness, has turned out to follow natural laws, that have been unclear for me at the present time.

Then "resurrection" depends on whether we have more observations than unknowns....how's the project of filling up the edge of spacetime with colossal detectors going...? And how long do we have to wait for the data..?

[Danail Bulgaria]

Who knows what the future will bring. We don't know the technologies of the future on the same way the people from the past didn't know our technologies. The example with the airplane. If we were talking about if human can fly 2000 years ago, you would keep asking but how that will happen, how this will happen, why that but not this. How big wings you have to make to fly like a bird, how will you move them, how many gooses you will have to shaggy, will there be enough gooses for shagging if everyone decides to fly.

 

The fact is only one - if there is no natural law to forbid something, this something can be made - now or in the future.

 

There is no scientific law, that to forbid backwards calculations with assumptions. So yes, I believe in the future this will be done. How the people will overcome the obsticles... well.. I don't know. On the very same way I wouldn't know how to build an airplane 2000 years ago. I only know its possible.

[platypus]

You are making a number of assumptions that need to be true for QA to work. Also you provide no kind of quantitative analysis of the problem. Therefore the case you make is quite weak. 

[Danail Bulgaria]

The most important is the idea not to be lost. The case will be becomming stronger and stronger with the time by the development of the human knowledge.

[platypus]

It does not matter if information is not lost if it's impossible to build detector-systems that capture the information. It's impossible also in theory to build a detector-system that can capture all information leaked from Earth during the time there has been life on Earth.

[Danail Bulgaria]

Alright. And who tells you, that it is impossible? Any law of physics? Any law of other sciences? Which one?

You can't be sure it will be made, but you can't be sure it is impossible.

For example building a perpetummobile is impossible, because it violates the law of energy preservation (energy is not being created ot lost, but transforms from one type to another).

Which law you violate when capturing information about atoms?

[N.T.M.]

Alright. And who tells you, that it is impossible? Any law of physics? Any law of other sciences? Which one?

You can't be sure it will be made, but you can't be sure it is impossible.

For example building a perpetummobile is impossible, because it violates the law of energy preservation (energy is not being created ot lost, but transforms from one type to another).

Which law you violate when capturing information about atoms?

 

I believe that his point is that the question is purely academic. While detectors could in theory be built, the magnitude of a project like that makes it very unlikely. Not impossible, just unlikely.