Physical Paradox

[Meridian]

I've been trying to argue that paradoxes are linguistic in form, like contradictions, but have met claims that 'physical paradoxes' are not. The example I've received is the so-called Grandfather Paradox. To make a summary, it is the apparent paradox of a man travelling back in time to kill his own biological grandfather; as a result making it impossible that the time-traveller would be conceived.

Personally, I think this 'paradox' makes some assumptions about time travel, and perhaps it rather points to faulty theory than to anything like a 'physical paradox'. However, it could be that there are other examples of apparent physical paradoxes?

I think this is interesting because I believe modern advancement in science can still produce metaphysical questions. But I have trouble unravelling it because of the scientific language I am unfamiliar with.

[Rosa Lichtenstein]

But, if the description of the attempt even to travel back in time is non-sensical, then there is no paradox.

May I suggest you read 'Causal Loops', by Michael Dummett on this. You can find it in his book, The Seas Of Language.

The following argument, in greatly simplified form, is my own version of it.

Suppose that at noon (Greenwich Mean Time) on the 10th of October, 2010 A wants to travel back in time, say, to noon October 10th, 1850, and to a specific location, for whatever reason.

If A does so, then it is now (i.e., at noon 10th October, 2010) true that she's already there (or the journey will have failed) If so, then when she tries to travel back to that time, she cannot travel back to the very same spot, or she would crush her past self.

So, she must travel back to a different spot, in the same location. But, if she does that then it is now true that she is already there, in both spots!

So, she must now travel to a different spot, or crush herself, once more.

But, and once again, if she does that, it must now be true that she is already there...

So, if it is possible to travel in time, then there will be an infinite number of 'copies' of A in the past.

Did anyone in 1850 report this odd fact?

Worse, if it is possible to travel back, or forward, to any point in time, then there must be an infinite number of A's at every point in time.

If this is so, it will be impossible for you to read this for all those copies of A in the way!

Or for you even to breath for the almighty crush of bodies everywhere.

[RedMaterialist]

To make a summary, it is the apparent paradox of a man travelling back in time to kill his own biological grandfather; as a result making it impossible that the time-traveller would be conceived.

One possible resolution of this paradox is that time travel is done in parallel or alternate universes. Thus, you might go back to a parallel universe, kill your grandfather, then return to the original universe. The idea of parallel, multiple, alternate universes appears to be gaining acceptance by scientists. If such a thing turns out to be true then it opens up almost infinite possibilities.

[Rosa Lichtenstein]

KM:


One possible resolution of this paradox is that time travel is done in parallel or alternate universes. Thus, you might go back to a parallel universe, kill your grandfather, then return to the original universe. The idea of parallel, multiple, alternate universes appears to be gaining acceptance by scientists. If such a thing turns out to be true then it opens up almost infinite possibilities.

This option fails to escape my refutation -- it's just more tedious to extend it into other 'dimensions' and 'parallel' time zones.

[RedMaterialist]

So, she must travel back to a different spot, in the same location. But, if she does that then it is now true that she is already there, in both spots! So, she must now travel to a different spot, or crush herself, once more

While this [I]may[I] be logically correct, it is not impossible. As I mentioned in the "Dialectic" thread, physicists have proven that two points can occupy the same location at the same time or at different times, one point can occupy different locations at the same time, or one location at different times. All of this is consistent with time travel. Most physicists agree that time travel is possible but would require more energy than now is known to exist in this universe.

[RedMaterialist]

RL


KM:


This option fails to escape my refutation -- it's just more tedious to extend it into other 'dimensions' and 'parallel' time zones.

Not parallel time zones, parallel universes. 'Tedious' multiple universes? I doubt even your old friend Kant would agree with that description.

By the way, I would assume you would agree that time cannot move at a different speed depending on how fast or slow you are going?

[Rosa Lichtenstein]

KM:


While this [I]may[I] be logically correct, it is not impossible. As I mentioned in the "Dialectic" thread, physicists have proven that two points can occupy the same location at the same time or at different times, one point can occupy different locations at the same time, or one location at different times. All of this is consistent with time travel. Most physicists agree that time travel is possible but would require more energy than now is known to exist in this universe.

Well, you miss the point; if it is possible to travel to any point in time, then it will thereby be impossible to do so, since every location at that point in time will be occupied by copies of the 'time traveller' concerned. There'd be no room for her.


Most physicists agree that time travel is possible but would require more energy than now is known to exist in this universe

And most physicists used to think the earth was at the centre of the universe.

[Rosa Lichtenstein]

KM:


Not parallel time zones, parallel universes. 'Tedious' multiple universes? I doubt even your old friend Kant would agree with that description.

1) Tedious to give the proof -- you need to read more carefully.

2) Kant is no more my friend than George W is yours.


By the way, I would assume you would agree that time cannot move at a different speed depending on how fast or slow you are going?

What happens is that clocks slow down. Time is unaffected.

[RedMaterialist]

KM


What happens is that clocks slow down. Time is unaffected.

Not only does time slow down, the aging process slows down. If you get on a space ship and travel near the speed of light (as I'm sure you've heard) in 20 years you will be 20 yrs older. Your dialectical opponent on earth will be thousands of years older.

Tedious proof of parallel universes? Seems like a pretty interesting idea to me.

Looking briefly at your anti-dialectic writings it is clear that you reject all things dialectic; you apparently believe that the dialectic has destroyed communism in Russia and is pretty much on the way to destroying communism in China, and, I suppose, in Vietnam.

If dialectical materialism has hi-jacked "true" communism, then whom should we read to get back on the right track? Apparently not even Trotsky is not pure enough for you.

[Rosa Lichtenstein]

KM:


Not only does time slow down,

You are confusing the measurement of time with time itself.


the aging process slows down.

And you know this how?


If you get on a space ship and travel near the speed of light (as I'm sure you've heard) in 20 years you will be 20 yrs older. Your dialectical opponent on earth will be thousands of years older.

So, this scientistic fantasy would have you believe, but there is no evidence for it.

You seem to be confusing science fiction and speculation with science itself.


Tedious proof of parallel universes? Seems like a pretty interesting idea to me.

My referene to a 'tedious' proof was to the job of extending my refutation into all the domains you have dreamt up, not those domains themsleves.


Looking briefly at your anti-dialectic writings it is clear that you reject all things dialectic; you apparently believe that the dialectic has destroyed communism in Russia and is pretty much on the way to destroying communism in China, and, I suppose, in Vietnam.

Where have I said this?


If dialectical materialism has hi-jacked "true" communism, then whom should we read to get back on the right track? Apparently not even Trotsky is not pure enough for you.

'Pure enough' (with respect to individuals) does not enter into science. I think you are confusing Historical Materialism with religious faith.

[¿Que?]

I don't know much about them, but I've always found Zeno's Achilles and the Turtle, The Dichotomy Paradox, and The Arrow Paradox inherently interesting.

[Rosa Lichtenstein]

^^^They all fail, too, since they use ordinary words in rather odd ways, just like the alleged paradoxes of 'time travel' use "time" in an odd way.

Indeed, as Marx indicated:


The philosophers have only to dissolve their language into the ordinary language, from which it is abstracted, in order to recognise it, as the distorted language of the actual world, and to realise that neither thoughts nor language in themselves form a realm of their own, that they are only manifestations of actual life." [Marx and Engels (1970) The German Ideology, p.118. Bold added.

And that is why the last 2400 years of philosophical speculation is almost entirely non-sensical.

I have tried to show how this is so with the 'time travel paradox' -- how it collapses into absurdity if we refuse to go along with this misuse of language -- but it can be extended quite easily to show how the other alleged 'paradoxes' also fall apart.

[Meridian]

Thanks for your contributions everyone.

I do agree with Rosa Lichtenstein in that time travel, at least along a singular time line, doesn't seem to make sense. I don't see how (f.ex.) the argument she posted can be disproved. Yet many scientists believe time travel could work. I suppose it is because they approach it from a more technical point of view, or that they believe in multiple time lines. Personally I doubt "time lines" are anything but representations we can make of successions of events, not unlike calendars, but obviously I am no expert in this area.

El Vagoneta, I am not really familiar with those paradoxes, but I would be interested in hearing about them.

[RedMaterialist]

And that is why the last 2400 years of philosophical speculation is almost entirely non-sensical.



Careful, you tread on dangerous ground. You dismiss intellectual giants like Socrates, Plato, Aristotle, Aquinas, Hobbes, Hume, Mills, Rousseau, Kant, Adam Smith, Hegel, Engels, Marx, as non-sensical. Why should we take seriously intellectual midgets like Max Eastman, who ended his life working for Joseph McCarthy?

[RedMaterialist]

So, this scientistic fantasy would have you believe, but there is no evidence for it.

You seem to be confuing science fiction and speculation with science itself.

Ahhh! Yes there is proof. If you have ever used a GPS device you have proved it yourself. The GPS device on earth moves at a slower speed than the satellite in orbit which it communicates with. The clock on the satellite moves just slightly slower than the clock in the GPS. Therefore, technicians on earth have to readjust the clocks every few hours to keep them synchronized. If they did not do this the GPS location would slowly become more and more inaccurate, until finally it would be off by hundreds of miles.

This is a practical application of the principle of Einstein's theory of relativity. Laboratory experiments since then have proven that time (or clocks, if you will) does slow down if the clock is moving faster relative to a clock that is moving slower.

[Rosa Lichtenstein]

Meridian:


I do agree with Rosa Lichtenstein in that time travel, at least along a singular time line, doesn't seem to make sense. I don't see how (f.ex.) the argument she posted can be disproved. Yet many scientists believe time travel could work. I suppose it is because they approach it from a more technical point of view, or that they believe in multiple time lines. Personally I doubt "time lines" are anything but representations we can make of successions of events, not unlike calendars, but obviously I am no expert in this area.

It's possible to show that even when there are 'multiple time lines' similar absurdities soon follow.


El Vagoneta, I am not really familiar with those paradoxes, but I would be interested in hearing about them.

Here they are:

http://en.wikipedia.org/wiki/Zeno's_paradoxes

http://plato.stanford.edu/entries/paradox-zeno/

You can find my post on 'What the Tortoise said to Achilles', here:

http://www.revleft.com/vb/philosophy-and-humor-t142696/index.html

[Rosa Lichtenstein]

KM:


Careful, you tread on dangerous ground. You dismiss intellectual giants like Socrates, Plato, Aristotle, Aquinas, Hobbes, Hume, Mills, Rousseau, Kant, Adam Smith, Hegel, Engels, Marx, as non-sensical. Why should we take seriously intellectual midgets like Max Eastman, who ended his life working for Joseph McCarthy?

Yes I know they are highly regarded, but not by me (except perhaps Aristotle). You can read why I think the philosophical ideas of all those I have highlighted descend into non-sense, here:

http://www.revleft.com/vb/showpost.php?p=1718346&postcount=61

And where did I say this of Adam Smith, or of Marx?

And I do not take Max Eastman seriously -- except in this one regard: he was right about you dialecticans.

[Rosa Lichtenstein]

KM:


Ahhh! Yes there is proof. If you have ever used a GPS device you have proved it yourself. The GPS device on earth moves at a slower speed than the satellite in orbit which it communicates with. The clock on the satellite moves just slightly slower than the clock in the GPS. Therefore, technicians on earth have to readjust the clocks every few hours to keep them synchronized. If they did not do this the GPS location would slowly become more and more inaccurate, until finally it would be off by hundreds of miles.

This is a practical application of the principle of Einstein's theory of relativity. Laboratory experiments since then have proven that time (or clocks, if you will) does slow down if the clock is moving faster relative to a clock that is moving slower.


Yes, I have already agreed that the measurement of time, with clocks and/or other devices, moves slower -- but that does not mean time does -- any more than if you run slower, time slows alongside you.

And we are still waiting for your proof that certain particles are 'entangled' right across the galaxy, let alone the universe.

As well as your proof that life/aging slows down.

[RedMaterialist]

[QUOTE=Rosa Lichtenstein;1892365]KM:


any more than if you run slower, time slows alongside you.


No, time goes faster the slower you run. Remember, the person in the spaceship stays the same age, relatively, while on earth it is 10K years later.


And we are still waiting for your proof that certain particles are 'entangled' right across the galaxy, let alone the universe.

Well, its been proven that the entanglement takes place across a few feet.
Even though there is no way the particles could be "aware" or "know" what the other one was doing. And, gravity was proven to work on Earth; it wasn't till about a hundred yrs ago it was proven to work anywhere else in the universe.

[Rosa Lichtenstein]

KM:


No, time goes faster the slower you run. Remember, the person in the spaceship stays the same age, relatively, while on earth it is 10K years later.

You keep saying things like this but you forget to tell us what the experimental or observational evidence there is that supports the odd idea that the aging process is affected in any way. I know this is said by some to be one implication of the theory, but as yet there is no evidence that we age slower or faster if we speed up or slow down.


Well, its been proven that the entanglement takes place across a few feet.

I acknowledged this in an earlier reply to you -- and pointed out that there are scientific realists (who are also physicists) who question the statistics upon which these experiments are based.

But, even if these experiments were 100% reliable, and totally unquestionable, there is as yet (nor could there ever be) experimental or observational proof that this occurs across the galaxy, let alone the rest of the universe.

This is quite apart from the fact that 'entanglement' violates the special theory of relativity.


Even though there is no way the particles could be "aware" or "know" what the other one was doing. And, gravity was proven to work on Earth; it wasn't till about a hundred yrs ago it was proven to work anywhere else in the universe.

Well, I'm not sure what that is supposed to prove. We can observe distant stars and galaxies moving as predicted in a gravitational field (which itself has yet to be shown to exist), but what observations can you point to that support the odd idea that 'information' can travel instantaneously across billions of light years?

Once more, even if this were so, there are other explanations of this phenomenon, should it ever be confirmed, that do not rely on 'entanglement'.

[RedMaterialist]

This is quite apart from the fact that 'entanglement' violates the special theory of relativity.

That is true; however, all of quantum mechanics violates the theory of special relativity.


Once more, even if this were so, there are other explanations of this phenomenon, should it ever be confirmed, that do not rely on 'entanglement'.

Entanglement is extremely interesting. I don't pretend to understand it, but it certainly has definite dialectical qualities to it. Here are some quotes from Wikipedia (not a definitive source, I know.) With my own editing..The page is EBR Paradox.

"Measurements on an entangled state:

"We have a source that emits a (negative) electron and a (positive) positron pair, with the electron sent to an observer named Alice, and the positron sent to an observer named Bob.... (The electron has spin -z and the positron has spin +z, which apparently is not certain...my note). However, it is impossible to say whether either particle has a definite spin. The particles are thus said to be entangled...

"Alice now measures her particle. She can obtain one of two possible outcomes: +z or -z. Suppose she gets +z. According to quantum mechanics... if Bob subsequently measures the spin of his particle will obtain -z with 100% probability. Similarly, if Alice gets -z, Bob will get +z." (all emphasis mine.)

This result violates the causality principle of special relativity.

However, it seems to happen. You can look it up. Also, according to the same Wiki article there are now practical applications of entanglement:

"Technologies relying on quantum entanglement are now being developed. In quantum cryptography, entangled particles are used to transmit signals that cannot be eavesdropped upon without leaving a trace. In quantum computation, entangled quantum states are used to perform computations in parallel, which may allow certain calculations to be performed much more quickly than they ever could be with classical computers."

[Rosa Lichtenstein]

KM:


Entanglement is extremely interesting. I don't pretend to understand it, but it certainly has definite dialectical qualities to it. Here are some quotes from Wikipedia (not a definitive source, I know.) With my own editing..The page is EBR Paradox.

Yes, I have in fact been reading up on this since the early 1980s.

It has important critics, who agree with Einstein, and who are scientific realists -- not Idealists, like those who invented this theory (entanglement).


However, it seems to happen. You can look it up. Also, according to the same Wiki article there are now practical applications of entanglement:

"Technologies relying on quantum entanglement are now being developed. In quantum cryptography, entangled particles are used to transmit signals that cannot be eavesdropped upon without leaving a trace. In quantum computation, entangled quantum states are used to perform computations in parallel, which may allow certain calculations to be performed much more quickly than they ever could be with classical computers."

Well, we'll see if these 'technologies' work. I've heard such things many times before, and nothing came of them. But, even if they do, they cannot possibly verify the idea that entanglement stretches across the entire universe.