Jump to content

What is "real" in physics?


swansont

Recommended Posts

 

I don't think a hole exists per se. It is an abstract concept like and probably related to the idea of 'nothing' ...it is a particular state of absence of something.

 

 

Without the existence of holes, you could not tie a knot and Topology would be a very different branch of Mathematics.

Just as number theory would be very different without a solution to the equation x2 = -1

Edited by studiot
Link to comment
Share on other sites

The hole is defined by the surrounding material (or the expanded spatial relations ^_^).

Most things consist of both presences and absences. If I fill the contours of a motor with hot steel to make a solid block of steel, I'm not taking anything away, yet I take away its motor-likeness. Would you really contend that every block of pure steel has a motor inside?

 

This looks to me like a nicer way of describing what I have proposed as units of the volume we call space. I like it even though I don't understand the "common focus" part.



Maybe a better term would be "common endpoint".
Rather than change independently, spatial relations always change in corresponding ways. For example, motion toward (lower distance from) you may correspond with motion away from (higher distance from) swansot.
"Motion" of a "common endpoint" denotes the collaborative adjustment of all spatial relations having that common endpoint as one of two endpoints. It's like a spider web, but with distance values instead of strands of spider silk.

Edited by MonDie
Link to comment
Share on other sites

 

Most things consist of both presences and absences. If I fill the contours of a motor with hot steel to make a solid block of steel, I'm not taking anything away, yet I take away its motor-likeness. Would you really contend that every block of pure steel has a motor inside?

 

No of course not, why should I ?

 

But I would contend that a block of pure steel containing a motor is different from one that does not. Just as any object with a hole is different from a similar one without.

 

 

The hole is defined by the surrounding material (or the expanded spatial relations ^_^).

 

 

 

Of course the hole has defining limits. The ones I offered before have material boundaries.

 

Various attempts have been made to create sustained artificial fusion reactors.

Do you know of any where the containment was within a material body?

In this case the containment (hole) was non material.

 

But thank you for your thoughts.

 

:)

Edited by studiot
Link to comment
Share on other sites

Pardon my earlier rather silly post. I was trying to get across that I am not just shooting the breeze, but trying to convey certainty.

 

Some responses to remarks above.

 

There is no such thing as a fundamental particle. This is obvious. In order to exist a particle requires the prior, or at least simultaneous, existence of time and space. Clearly, then, particles are not fundamental.

 

The question of whether something that is non-physical can exist is an easy one. We all know that this is possible. Even if all mental phenomena have a physical correlate, they are still not res extensa.

 

The more difficult question is whether something can exist if it is fundamental. If it is fundamental then it has an independent existence. Otherwise is has only a relative existence. But how, if it is independent, can it exist in the absence of space and time? It cannot. This is why the only fundamental theory that makes the slightest bit of sense would state that what is fundamental does not exist in time and space, and, also, that it would be misleading even to state that it exists. Rather, it would be real. Sometimes people describe it as existing and not-existing, allowing for the two ways we might conceive of it.

 

I say 'it', but of course we're talking here about the source of every phenomena and 'the world as a whole, so we cannot actually separate ourselves and describe it as an object.

 

The logic would be what is important here. A fundamental theory for which the Absolute exists in the same way as the Moon will inevitably fail and have to remain non-reductive. This is the reason why physics cannot understand ex nihilo creation. It sees the absence of time and space and assumes this must be Nothing. It is a good theory, but it is non-reductive. For it to work, we would need a phenomenon that looks exactly like Nothing to any observer, but is in fact the source of all existence.

 

Either that or it's turtles all the way down.

Edited by PeterJ
Link to comment
Share on other sites

There is no such thing as a fundamental particle. This is obvious. In order to exist a particle requires the prior, or at least simultaneous, existence of time and space. Clearly, then, particles are not fundamental.

 

It's not obvious to me that time and space didn't exist prior to particles.

 

The question of whether something that is non-physical can exist is an easy one. We all know that this is possible. Even if all mental phenomena have a physical correlate, they are still not res extensa.

 

The more difficult question is whether something can exist if it is fundamental. If it is fundamental then it has an independent existence.

 

I don't think you're using fundamental the way it's usually used in physics.

Link to comment
Share on other sites

Yes, I'm not using it the way physics uses it. I'm using the dictionary definition. Physics uses the phrase 'fundamental physics', a phrase which assumes that whatever is fundamental is observable, like a planet or hydrogen. I'm suggesting that there is no such thing as fundamental physics.

Link to comment
Share on other sites

In physics, fundamental particles are ones with no structure and can't be broken down, e.g. electrons and quarks. Fundamental physics is at the lowest level we can observe, e.g. tests of the standard model.

Link to comment
Share on other sites

 

So there are no fundamental particles, according to this view.

No, I suggested that the units of space are the fundamental particles and that they are not capable of initiating any independent action; they are inert.

 

The obvious implication is that some external influence was required to get them moving and produce all the phenomena we experience. I anticipate your response to be that a posited external influence means that space is not fundamental. I agree. So I must limit the idea of units of space being fundamental to them being the fundamental units of space and not the fundamental units of a posited external influence or some external environment.

 

Science is limited to what can be discovered. I expect that anything apart from space will not be discovered. I will not deny that space could be a sub-set of something external, but I don't see how we could know that without leaving space.

Link to comment
Share on other sites

Okay, I get that Swansont. I suppose it's a fair use of the word if it means the lowest level accessible to physics. But it is very misleading term outside of physics. It could be interpreted to mean that particles that are indivisible are fundamental.

 

Didn't someone recently split an electron? I'm sure I read about the experiment somewhere.

 

Fred - I feel you are stuck in physics mode, whereby we can know nothing except what our physical sense can detect. We'll probably have to go on disagreeing about this.

Edited by PeterJ
Link to comment
Share on other sites

 

I will not deny that space could be a sub-set of something external, but I don't see how we could know that without leaving space.

 

 

You could claim the same about being unable to discover what happens in the sky, without leaving the planet's surface.

But it has probably been known since prehistoric times that clouds cast shadows.

 

You could say the same about what happens in nearby space without leaving the planet.

Again eclipses and other occlusions have been observed since antiquity.

 

You could say the same about outer space without leaving the solar system.

But what about the prediction and subsequent discovery of Le Verrier's Planet?

 

So I could continue to extend outwards, you get the drift.

Link to comment
Share on other sites

Or, we can leave space. Obviously this is not usually thought to be possible in physics, although a few well-known physicists have argued that it is. I cannot prove that it is. But a vast quantity of people claim that it is possible to transcend time and space to see what is prior. For instance, seeing as how I've already blotted my copybook by mentioning Lao-tsu, he would be one of them. He writes 'Knowing the ancient beginnings is the essence of Tao'. That is to say, his Taoism is all about knowing this.

 

I'm not trying to derail the thread. It's just that this other view should at least get a mention. For Lao-tsu Taoism is not a religion but a philosophy and metaphysical scheme. As such, it works, and overcomes the problems that are being discussed here. Just because it would work is, I agree, not a reason to fall over and endorse it. But neither can we completely dismiss it without coming up with something better.

 

Some people who argue for the views of Lao-tsu and his like are anti-science. I am not anti-science, but I wish its limits were better recognised.

 

Massimo Pugliucci has just posted a relevant article on this topic at Scienta Salon subsequent to his hosting a discussion between Brian Greene and Peter Galison. My browser won't copy the link, but it'll be googlable under the title 'The Evidence Crisis' - Scienta Salon (his blog and online journal).

Link to comment
Share on other sites

Didn't someone recently split an electron? I'm sure I read about the experiment somewhere.

 

No. There are composite systems where charge is spin are localized differently, but that's not the same thing as splitting an electron.

Link to comment
Share on other sites

I would have thought Scientific American was careful enough for most people.

 

You need to look at the details of the article, not just the headline or the teaser. The "split" was in a composite system. Saying it was an electron is lazy and sensationalist.

Link to comment
Share on other sites

Okay Thanks for the clarification. A lot of people have said the same thing though. There are dozens of articles out there explaining this as 'splitting' an 'electron'. Yet, despite this torrent of news, an electron has not been split. It's no wonder people get the wrong idea about such things. Anything for a headline I suppose.

 

It makes no difference to me whether an electron has been split or not, so I'm certainly not arguing, but there's something I do not understand here.

 

The Scientific American article begins...

 

"In a feat of technical mastery, condensed matter physicists have managed to detect the elusive third constituent of an electron - its 'orbiton'"

 

How can this be announced if it is a fact that an electron has no constituents?

Link to comment
Share on other sites

 

You could claim the same about being unable to discover what happens in the sky, without leaving the planet's surface.

But it has probably been known since prehistoric times that clouds cast shadows.

 

You could say the same about what happens in nearby space without leaving the planet.

Again eclipses and other occlusions have been observed since antiquity.

 

You could say the same about outer space without leaving the solar system.

But what about the prediction and subsequent discovery of Le Verrier's Planet?

 

So I could continue to extend outwards, you get the drift.

Yes, I get your point. I think the discovery of something outside space could be accomplished only if space were finite, situated in a larger volume of a universe of something that is not-space and something in that not-space were interacting with matter in our space. This is way too far from our experience for me to buy into it.

 

Could it be possible? Maybe. Is it likely that we could recognize it? I doubt it, mostly because we are creatures of our space and I expect we just don't have the physical makeup required to experience anything other than our space. Never say never of course, but I think we will have to discover much more about our space before we have evidence sufficient to seriously postulate a larger environment.

Link to comment
Share on other sites

...

Fred - I feel you are stuck in physics mode, whereby we can know nothing except what our physical sense can detect. We'll probably have to go on disagreeing about this.

I don't want to limit what we can experience to "our physical sense". Hume used the term "experience" when he said all we can know is what we experience. The implication is that experience may include more than physical sense.

 

However, is it not true that for quite a long time now the consensus philosophy in science has been that we can accept as true only what we can observe and such observation is limited to our senses (and our machines which enhance our senses)? Even our most advanced machines must "show" us something in order for us to accept it.

 

If this is "physics mode" then, when it comes to physics, I'm in it. Tell me how a blind man can gather evidence on his own sufficient to accept that there are stars.

Or, we can leave space. Obviously this is not usually thought to be possible in physics, although a few well-known physicists have argued that it is. I cannot prove that it is. But a vast quantity of people claim that it is possible to transcend time and space to see what is prior. For instance, seeing as how I've already blotted my copybook by mentioning Lao-tsu, he would be one of them. He writes 'Knowing the ancient beginnings is the essence of Tao'. That is to say, his Taoism is all about knowing this.

 

I'm not trying to derail the thread. It's just that this other view should at least get a mention. For Lao-tsu Taoism is not a religion but a philosophy and metaphysical scheme. As such, it works, and overcomes the problems that are being discussed here. Just because it would work is, I agree, not a reason to fall over and endorse it. But neither can we completely dismiss it without coming up with something better.

 

Some people who argue for the views of Lao-tsu and his like are anti-science. I am not anti-science, but I wish its limits were better recognised.

 

Massimo Pugliucci has just posted a relevant article on this topic at Scienta Salon subsequent to his hosting a discussion between Brian Greene and Peter Galison. My browser won't copy the link, but it'll be googlable under the title 'The Evidence Crisis' - Scienta Salon (his blog and online journal).

If you can accept that religion is a philosophy for living, then isn't Taoism a religion? I see philosophy of or about a subject as the approach to that subject. Everyone approaches living their life in some way. That way is their philosophy and, consequently, their religion. It may not be well thought out, codified or deliberate but it is what they do and since everyone does his or her own thing as they live their life, to me, everyone practices his or her own religion.

 

I accept my own experiences beyond my five physical senses, and I have had several, as true or real but I am not able to provide physical evidence of them or share them with others. Since I cannot present evidence of them, I cannot ask others to include them in our physics. However, there are enough anecdotal accounts of such experiences from others, especially when I consider my own, for me to accept that there is something that happens beyond our five senses.

 

My understanding of metaphysics is that it is where we express our a priori notions and our experiences beyond our five senses. In light of the fact of continuing discoveries, I can think of metaphysics as the "bleeding edge", in today's terms, of physics. It seems to me that throughout history, and before, a priori notions have given way to theories which have given way to discoveries which have forced and allowed us to develop more a priori notions. In other words, it seems right to me to include metaphysics as the "first chapter" in our physics book.

Edited by Fred Champion
Link to comment
Share on other sites

Okay. Let's agree to differ about the limits of physics and whether it is capable of describing the world.

 

But let us for the moment suspend disbelief sufficiently to concede that it might not be. Then we can talk about Taoism and metaphysics. .

 

Metaphysics takes the results of physics as a priori knowledge and extrapolates from it in an attempt to explain these results within a fundamental or completely general theory. So it is both the first chapter and the last. It comes both before and after physics. It also takes into account phenomena that are not observable, consciousness being the most prominent.

 

Metaphysics says, okay, so we have nonlocal effects, curved space, Higgs fields, cause and effect, the laws of logic, our human ability to reason, the evidence of our own senses, the evidence of our own experiences, the findings of many generations of philosophers and so forth. Let us put them all in the mix and see if we can construct a fundamental theory that would explain how all this is possible.

 

Really it is just thinking. When we look for an interpretation of QM, we are thinking about metaphysics. I cannot understand why physicists are so allergic to it.

 

Taoism grows out of three texts in particular, the Lao-tsu, Chuang-tsu and a third the name of which slips my mind for now. These are philosophical texts. You might argue, as you do, that all philosophy might as well be religion, but I think you'd struggle to define these words in such a way as to make them synonyms. Whitehead calls the Christianity he knew 'a religion is search of a metaphysic', and this seems the correct use of the words to me.

 

Religious Taoism, (which is an official branch of Taoism), was created about 500 years after Lao tsu. Gods were invented, along with a punishment and reward system, heaven and hell and all that, and Lao-Tsu was elevated to sainthood. From a philosophical perspective this might be seen as a degeneration of Taoism. But it nicely illustrates how a perfectly good philosophical doctrine can be turned into an incomprehensible muddle of beliefs and dogmas. It explains how it is possible to agree with Whitehead, while nevertheless believing that the writings of, say, Meister Eckhart, represent a sound metaphysical position.

 

You look at Taoism and see it just as Whitehead sees Christianity. But in both cases the core philosophy that underlies all the surface clutter of these religions is being ignored.

 

As you say, everyone practices their own religion. In metaphysics things are different. We have to demonstrate our arguments and make them valid and sound, and where they reach a result we are not free to endorse some other result, as if it was all a matter of opinion. If Lao-tsu's and Chuang-tsu's description of the world is wrong then let us falsify it. But let us not dismiss it unthinkingly on religious grounds. Religion has nothing to do with anything in metaphysics. Or not unless we are prepared to let our reason be infected by temperament and prejudice, and limited by dogma and orthodoxy.

 

It's the metaphysical scheme of Lao-tsu that is of interest in physics, not any of the later religious elaborations. In physics there is no case for walking in his footsteps, no grants would be available for ten years sitting in meditation, but we can easily examine what he claims to have discovered for its plausibility and usefulness, especially since as yet we have no better fundamental theory.

 

This is off the cuff. Hopefully it isn't all waffle.

Edited by PeterJ
Link to comment
Share on other sites

In my view, yes and no.

 

Empiricism has never succeeded in overturning a result of metaphysical analysis. This could be seen as constituting an empirical proof of these results. But this argument is not overwhelming and you may not agree.

 

I could point to a few million first-person reports confirming the results of metaphysics, but these would not constitute empirical evidence for a sceptic, just a massive coincidence. Some people reject consciousness as a scientific phenomenon for this reason, that there is no empirical proof for it. .

 

I could point to the elegance, simplicity and systematic integrity of the fundamental theory that emerges if we take metaphysical results seriously. But this argument doesn't work for string theory so it might be rejected.

 

I could point to the fact that no fundamental theory that ignores the results of metaphysics works. But I'm not sure this could be called empirical evidence.

 

All in all, I think that to do metaphysics we have to imagine that we were given a brain for a reason and might as well use it, and then use whatever standards of proof and evidence we can find. There is no empirical proof that all apples fall down, but induction seems a reasonable reason for imagining they do. There is no empirical proof that Materialism is true, and never will be, but it is a metaphysical theory that some people like, so they argue that there are logical reasons for endorsing it. There are double standards.

 

I would concede that in the sense that a physicist would use the word there is no empirical proof for metaphysical results. That is why they are metaphysical results. But in this case the OP's question 'What is real in physics' is a serious category error. It is not a question for physics. The only way to decide would be to work it out or use a form of empiricism that physics at this time does not recognise. Or, it is just asking 'what do physicists usually assume is real', which is an easy one. .

 

For myself, I see no point in drawing any kind of line between physics and metaphysics until it can be shown that they are not entirely consistent in their findings. But I'd have to agree that the evidence of our physical senses is never going to be able to decide questions such as what is real. .

 

If I may say some more. I respect your scepticism Swansont, and feel you take a thoughtful approach to these things. My problem here and elsewhere is that I am one of the most dogged critics of the way metaphysics is usually done. So when you criticise metaphysics I am torn between agreeing with you and defending it. You might appreciate this dilemma, since good physicists must often face the problem of defending physics in the face of the bad work that some people do, overstated claims, hasty conclusions, experimental errors, fraud and so forth. So I will defend the methods of metaphysics to the death, but I would not defend for a moment what passes for metaphysics in academia, which seems utterly dishonest and pointless to me.

Edited by PeterJ
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.