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What will future science say of today's science? (split from So are quantum entangled or teleported particles instantly there)

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On 11/3/2018 at 2:52 AM, Eise said:

So if I change the charge of one plate, somebody can measure an instantaneous change at the other plate. Wouldn't that be a violation of special relativity?

@Menan

You show that you do not understand entanglement. 

Let's go one step at a time. First a classical example. I have a bag of balls, they are all red or green. Without looking I pick two balls, and I put them in separate boxes. I keep one, and send the other far away. Then I open my box, and see it is a green ball. What can I conclude about the colour of the ball in the remote box? Right, nothing. And why? Because there was nothing special with my picks. It could have been two reds, two greens, or one red and green.

Now I pick, looking of course, one red and one green, and put them in two separate boxes. So what I did here is 'entangle' the balls. Now I shuffle the two boxes, so that I do not know which one is which. If I open one, and see that it is red, I immediately know that the ball in the other box is green. And of course, this is independent on the distance. If I send the second box lightyears away, and only then open my box, I still know immediately what some alien sees when he opens his box. I know it because the observations are correlated. And the correlation already happened at the moment of my picks. That is the moment of entanglement. It is not when the boxes are opened.

Now in quantum physics, there are processes where two particles pop out, which have e.g in one aspect always opposite values. Say the direction of spin. So if I measure the spin e.g. in a vertical direction, say it is 'up', then I immediately know that the other one will measure spin 'down', when also measured in the vertical direction. But as with the balls, the 'moment of entanglement' is when these particles popped into existence. But in quantum physics a few things are different: first, it is impossible to say which particle has which spin without measuring (it is as if I created the green and red balls, including their boxes, without knowing which ball is in which box). But as the two particles are entangled, if I measure both, the measurements will always be correlated. And there is nothing special with correlation: if I send one particle far away, and then measure my particle in the vertical direction, and the alien measures his particle in the same direction, I will always know what he measures: the opposite of my measurement. 

The 'spooky' aspect comes in when we do not know from each other in which direction we measure the spin. It can be vertical, horizontal, 30o, 45o, 55.3977o. What we find is that the correlation is stronger than one would expect if we would assume that the particles already had a definite spin from the beginning. But it still is correlation, not causation. As with the red and green balls, there is no direct causal relationship between my and the alien's observation. The causal relationship goes back to the moment of 'entanglement'. Everything afterwards is just correlation, and therefore cannot be used to transfer information. And because there is no causal relationship between my measurement of the spin of my particle, and the alien's measurement, I cannot use entanglement for sending information. 

And all this is very well understood by all quantum physicists, and is no secret at all.

You made good illustrations .. but in the end you fail where most science fails in thinking you are at the end of the answer instead of the beginning of further understanding.  One quote on this forum concerns facts as if they are facts .. but facts are facts only until new facts make the old facts unfacts, and thousands of years of science are full of examples.  Modern science says, 'Those old sciences were not sciences at all.'  What will future science say of today's science?  

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27 minutes ago, coffeesippin said:

You made good illustrations .. but in the end you fail where most science fails in thinking you are at the end of the answer instead of the beginning of further understanding.  One quote on this forum concerns facts as if they are facts .. but facts are facts only until new facts make the old facts unfacts, and thousands of years of science are full of examples.  Modern science says, 'Those old sciences were not sciences at all.'  What will future science say of today's science?  

It doesn't matter. What matters is that they are useful today. Scientific theories are not about truth, they are about usefulness. Todays facts may not be as useful in the future because they have subsequently found facts that are even more useful. What it usually means is that modern facts cover/explain  a wider range of situations. For example, Newtons gravity has been supplanted by General Relativity but it will still get you to the Moon. What GR offers is greater usefulness on top of being able to get to the Moon.

Edited by StringJunky

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3 minutes ago, StringJunky said:

It doesn't matter. What matters is that they are useful today. Scientific theories are not about truth, they are about usefulness.

An honest reply .. more the mind of an economist than a normal scientist, but I guess economy is a science too.  A big problem in accepting usefulness and putting it into practical work is Consensus .. if the consensus says the theory is not useful, it prevents time and talent and money going into a theory .. and then someone outside that power structure comes along, perhaps a someone in another nation, proves the theory to be useful after all, and there nation gains supremacy over the other nation.    

26 minutes ago, StringJunky said:

It doesn't matter. What matters is that they are useful today. Scientific theories are not about truth, they are about usefulness. Todays facts may not be as useful in the future because they have subsequently found facts that are even more useful. What it usually means is that modern facts cover/explain  a wider range of situations. For example, Newtons gravity has been supplanted by General Relativity but it will still get you to the Moon. What GR offers is greater usefulness on top of being able to get to the Moon.

As was pointed out to me, a fact that is not a fact is not a fact.  Our perception of something as a fact may make that perception useful to us, or not, but it does not make it a fact.  If it is a fact, it won't change if worded carefully enough .. 'at this time and date the earth is so many miles from the sun.'   That distance might not be the fact next week.  Also, I don't work for NASA in calculating trajectories for spacecraft, so I don't know if GR supplants Newton's gravity for those things.  The English language, I find more and more, consists of definitions of the same words which do not complement each other.  Does GR replace Newton, or add to Newton?  Just venting my frustration.  

sup·plant
/səˈplant/
verb
past tense: supplanted; past participle: supplanted
  1. supersede and replace.
    "another discovery could supplant the original finding"
    synonyms: replace, supersede, displace, take over from, substitute for, override 

 

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1 hour ago, coffeesippin said:

An honest reply .. more the mind of an economist than a normal scientist, but I guess economy is a science too.  A big problem in accepting usefulness and putting it into practical work is Consensus .. if the consensus says the theory is not useful, it prevents time and talent and money going into a theory .. and then someone outside that power structure comes along, perhaps a someone in another nation, proves the theory to be useful after all, and there nation gains supremacy over the other nation.   

 I would have listed consensus as useful rather than a 'big problem'. It keeps people from wasting time and talent and money on theories that are not useful.

1 hour ago, coffeesippin said:

You made good illustrations .. but in the end you fail where most science fails in thinking you are at the end of the answer instead of the beginning of further understanding. 

In my experience science never thinks it has found the final answer and can quit examining. Science ALWAYS reviews, looking for better understanding.

1 hour ago, coffeesippin said:

An honest reply .. more the mind of an economist than a normal scientist,

I think you've been looking in the wrong place. I've never seen any scientist say "Ah, we've finally found the "truth"". Science seeks an understanding of how the universe behaves. It is philosophers and lawyers who look for the truth.

Edited by zapatos

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4 hours ago, coffeesippin said:

You made good illustrations .. but in the end you fail where most science fails in thinking you are at the end of the answer instead of the beginning of further understanding. 

Well, I personally think that in QM we are at some kind of end. In this case the end is that we cannot look behind our measurements. That would be a contradiction. To understand what 'really' happens in EPR/Bell situations is a question that asks to go beyond what we can observe. And that is a dead end per definition. We can only accept what the equations of QM predict, and find situations in which we can use them for even more astonishing feats than the EPR/Bell experiments themselves: topics like quantum computing, quantum encryption, 'teleporting', quantum erasers, experiments to observe quantum effects on scales visible for the (nearly) naked eye, etc come to mind. But these are all applications from the same underlying principles.

4 hours ago, coffeesippin said:

One quote on this forum concerns facts as if they are facts .. but facts are facts only until new facts make the old facts unfacts, and thousands of years of science are full of examples.

Sorry this gets at your head now (I've seen this use of 'facts' already more often by other posters here ('Evolution is a fact')), but I hate this kind of misuse of the word 'facts'. Facts for me are true descriptions of concrete events, occurring at a certain place and time. So science is based on facts, but its results are theories: abstract descriptions of classes of events. Science can err on many places. To name a few: it may have its facts wrong (i.e. wrong descriptions of events), it can have plain wrong theories (phlogiston), or it supposes that its domain of application is bigger than it in fact is (classical vs relativistic mechanics). 

This third category is what concerns us here: with the relative small masses and velocities in daily life we get our facts right within measurable limits. So classical mechanics is still valid, but as a limit of relativistic mechanics. Now it is my educated guess that the situation for EPR/Bell situations will turn out to be at most such a limiting case (valid based on the specific values of our parameters), but even more probable, as I argued above, really the last word.

@String Junky: Now, can you rewrite your post, based on a better usage of the concepts of 'facts' and 'theories'...

4 hours ago, StringJunky said:

Scientific theories are not about truth, they are about usefulness.

Really? I think there is more than just 'usefulness'. To be honest, I like the 'truth aspect' of science very much (e.g. like the topic at hand), but I am less enthusiastic about the ways it is useful (atomic bombs?). But that would lead to a totally different discussion.

4 hours ago, coffeesippin said:

Does GR replace Newton, or add to Newton?

Matter of taste. GR explains why we believed Newton was correct: in the limiting case of low speeds and masses we get Newton's equations. 

3 hours ago, zapatos said:

I've never seen any scientist say "Ah, we've finally found the "truth""

Hmmm... If you would have written 'Truth' I would agree with you. But I would defend that science has found many 'truths'. With established scientific theories applied to their domains of validity, we can predict events, given initial conditions. I think that is as close to 'truth' you can get. In natural science, knowing the causal role of its objects, is knowing the objects. Science should not pretend more, but surely also not less.

4 hours ago, zapatos said:

It is philosophers and lawyers who look for the truth.

No, definitely not. Lawyers apply man made rules in such a way to gain maximum results. Philosophers try to clarify our way of thinking in different areas, scientific thinking being one of them. Maybe you are thinking about old-fashioned metaphysics, in which is speculated about how the world is 'behind the scenes'. But, again per definition, this is doomed to stay speculative, because in science we deal with the scenes themselves, and therefore can observe and experiment. If we could do 'metaphysical experiments', then it is not metaphysics anymore, but science.

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6 hours ago, coffeesippin said:

but in the end you fail where most science fails in thinking you are at the end of the answer instead of the beginning of further understanding. 

You are mistaking a description of our current understanding for a statement of fact. This is a science forum. Everyone knows that theories are provisional and subject to change with new evidence. It doesn't need to be a stated  every time. 

5 hours ago, coffeesippin said:

if the consensus says the theory is not useful, it prevents time and talent and money going into a theory .. and then someone outside that power structure comes along, perhaps a someone in another nation, proves the theory to be useful after all, and there nation gains supremacy over the other nation. 

Such paradigm shifts happen fairly frequently  -  there have been several in my lifetime. I'm not sure how you think this is related to nation states. Most science today is completely multinational. 

5 hours ago, coffeesippin said:

As was pointed out to me, a fact that is not a fact is not a fact. 

Science is not really about "facts". I suppose you could call evidence "facts" but evidence can change. 

 

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1 hour ago, Eise said:

Well, I personally think that in QM we are at some kind of end. In this case the end is that we cannot look behind our measurements. That would be a contradiction. To understand what 'really' happens in EPR/Bell situations is a question that asks to go beyond what we can observe. And that is a dead end per definition. We can only accept what the equations of QM predict, and find situations in which we can use them for even more astonishing feats than the EPR/Bell experiments themselves: topics like quantum computing, quantum encryption, 'teleporting', quantum erasers, experiments to observe quantum effects on scales visible for the (nearly) naked eye, etc come to mind. But these are all applications from the same underlying principles.

Sorry this gets at your head now (I've seen this use of 'facts' already more often by other posters here ('Evolution is a fact')), but I hate this kind of misuse of the word 'facts'. Facts for me are true descriptions of concrete events, occurring at a certain place and time. So science is based on facts, but its results are theories: abstract descriptions of classes of events. Science can err on many places. To name a few: it may have its facts wrong (i.e. wrong descriptions of events), it can have plain wrong theories (phlogiston), or it supposes that its domain of application is bigger than it in fact is (classical vs relativistic mechanics). 

This third category is what concerns us here: with the relative small masses and velocities in daily life we get our facts right within measurable limits. So classical mechanics is still valid, but as a limit of relativistic mechanics. Now it is my educated guess that the situation for EPR/Bell situations will turn out to be at most such a limiting case (valid based on the specific values of our parameters), but even more probable, as I argued above, really the last word.

@String Junky: Now, can you rewrite your post, based on a better usage of the concepts of 'facts' and 'theories'...

Really? I think there is more than just 'usefulness'. To be honest, I like the 'truth aspect' of science very much (e.g. like the topic at hand), but I am less enthusiastic about the ways it is useful (atomic bombs?). But that would lead to a totally different discussion.

Matter of taste. GR explains why we believed Newton was correct: in the limiting case of low speeds and masses we get Newton's equations. 

Hmmm... If you would have written 'Truth' I would agree with you. But I would defend that science has found many 'truths'. With established scientific theories applied to their domains of validity, we can predict events, given initial conditions. I think that is as close to 'truth' you can get. In natural science, knowing the causal role of its objects, is knowing the objects. Science should not pretend more, but surely also not less.

No, definitely not. Lawyers apply man made rules in such a way to gain maximum results. Philosophers try to clarify our way of thinking in different areas, scientific thinking being one of them. Maybe you are thinking about old-fashioned metaphysics, in which is speculated about how the world is 'behind the scenes'. But, again per definition, this is doomed to stay speculative, because in science we deal with the scenes themselves, and therefore can observe and experiment. If we could do 'metaphysical experiments', then it is not metaphysics anymore, but science.

. Truths cannot change and science changes.

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1 hour ago, StringJunky said:

. Truths cannot change and science changes.

So it could be that we discover tomorrow that objects that fall on earth will not fall according to our present knowledge? That's why I like to distinguish between scientific theories in general, which might be speculative (e.g. tested in a limited number of cases, or not even that), and established scientific theories, on which e.g. we base our technology, and are even prepared to bet our lives on it. Would you not fly on a modern airplane, because QM might be false, and as computers are based on QM. and planes are completely dependent on computers?

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1 hour ago, Eise said:

So it could be that we discover tomorrow that objects that fall on earth will not fall according to our present knowledge? That's why I like to distinguish between scientific theories in general, which might be speculative (e.g. tested in a limited number of cases, or not even that), and established scientific theories, on which e.g. we base our technology, and are even prepared to bet our lives on it. Would you not fly on a modern airplane, because QM might be false, and as computers are based on QM. and planes are completely dependent on computers?

QM might be false because it may not be a complete description of nature in some future analysis, but it is useful right now. I think it is a matter of principle towards always keeping an open mind that many scientists avoid saying something is 'the truth'.

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17 minutes ago, StringJunky said:

QM might be false because it may not be a complete description of nature in some future analysis, but it is useful right now. I think it is a matter of principle towards always keeping an open mind that many scientists avoid saying something is 'the truth'.

I agree, when you talk about 'the truth'. Or better 'The Truth'. But I think that in in established scientific theories we find many 'truths'. If it turns out that QM is not complete, it will hardly effect the fact that we can e.g. recognise hydrogen by the Balmer series. And airplanes will not fall from the air because QM is not complete. 

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6 hours ago, Eise said:

Sorry this gets at your head now (I've seen this use of 'facts' already more often by other posters here ('Evolution is a fact')), but I hate this kind of misuse of the word 'facts'. Facts for me are true descriptions of concrete events, occurring at a certain place and time. So science is based on facts, but its results are theories: abstract descriptions of classes of events.

How does claiming evolution to be a fact change this? Evolution happens (how could it not?), and the Theory of Evolution explains the process. One is fact, the other theory and subject to change as we discover new evidence. 

As to the OP, it's highly unlikely any present theory is going to be completely overthrown (although the methodology allows this could happen). There's simply been too many successful predictions based on mainstream theory to throw it all out. Changes will happen, but they're refinements rather than total game-changers.

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Evolution is both fact and theory (it's a floor wax and a dessert topping!)

Evolution has happened and is happening — that is a fact. The theory that explains the process is also called evolution.

It may be a tad unusual (and thus confusing), because we don't call the theory behind the cat pushing something off a table and having it fall on the floor ( a thing that happened and is thus a fact) the theory of things falling on the floor, or the theory of why things fall. We call it gravity (or, on occasion, General Relativity) 

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1 hour ago, Phi for All said:

As to the OP, it's highly unlikely any present theory is going to be completely overthrown (although the methodology allows this could happen). There's simply been too many successful predictions based on mainstream theory to throw it all out. Changes will happen, but they're refinements rather than total game-changers.

I'm not so sure. There have been a couple of major paradigm shifts just in my lifetime. We have gone from a static Earth to plate tectonics, with continents drifting around and colliding (although, maybe that doesn't count as so many people - pretty much every child - had noticed things like the similarity of the coastlines of South America and Africa, for example). And then we went from a static, eternal universe to one that is expanding and appears to have a finite life. There could be others, but it is probably impossible to guess where they might be.

1 hour ago, swansont said:

Evolution is both fact and theory (it's a floor wax and a dessert topping!)

Evolution has happened and is happening — that is a fact. The theory that explains the process is also called evolution.

Similarly, gravity is a fact (things fall down). But facts at that level of detail are not very useful. Once you start getting data (in what way have species changed, how fast things fall) then that can be evidence in support of (or against) a theory.

But that evidence is subject to change and reinterpretation as we get more and more accurate data.

So the facts themselves are of limited use (other than saying: we should look into this). And the evidence can't always be considered factual, as it is provisional.

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9 hours ago, Eise said:

Sorry this gets at your head now (I've seen this use of 'facts' already more often by other posters here ('Evolution is a fact')), but I hate this kind of misuse of the word 'facts'. Facts for me are true descriptions of concrete events, occurring at a certain place and time.

So how should it be called then. When we look gene pools we observe that they generally change over time. Isn't this a fact? Or perhaps a different example. If we measure outside temperature we will see that it fluctuates throughout the day. Is that a fact? If so, what is the difference between these two statements?

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Well, this seems more or less a semantic discussion. I just like, for clarity of discussion, to distinguish between singular facts (true descriptions of events) and correct theories (that are abstract, i.e. do not contain any singular facts, but with specific initial conditions can be used to predict events).

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3 hours ago, Eise said:

Well, this seems more or less a semantic discussion.

A little disappointed to see that from you :) (I hate it when people dismiss (*) an argument with "it's just semantics". Of course it is semantics, we are discussing the meanings of words!)

But agree completely with your point

Edit: (*) I know this is not what you are doing 

Edited by Strange
Footnote

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