Renormalization - a dippy process - R. Feynman

[Buckeye]

Buckeye, your ignorance of experimental high energy physics doesn't imply that the successes of the Standard Model are only theoretical in nature. If you want to read up on how successful the Standard Model is, go to the library.

Now as for the success of perturbative field theory methods, look no further than calculating the fine structure constant. You will find the theoretical prediction to be very close to the experimental value.

Could you be more specific as to my alleged ignorance of experimental high energy physics? Now you have my attention. Fine Structure Constant. Please give me a few words on PFT and how it is used to calculate "alpha". Thanks!

 

[Buckeye]

Name one
PLEASE STOP INSOLTING US. This is annoying. Because we know more than you do and you are frustrated about it does not give you the supreme right to have public contempt towards us

If you are that much smarter than me, then why haven't you developed a more even temperment? If you want to use the word "supreme", then maybe you should note that my last name is a derivative of a name used to identify: the followers of Christ.

 

[Normouse]

Testie professionals

If you are that much smarter than me, then why haven't you developed a more even temperment? If you want to use the word "supreme", then maybe you should note that my last name is a derivative of a name used to identify: the followers of Christ.

I am a little surprised how sensitive the physicists are to a little questioning of what they so thoroughly believe in. I don't find Buckeye's questions particularly aggressive. As a matter of fact I think similarly sometimes about how physicist attack and explain phenomena. I hate to break it to you but it seems a little closed to outsiders. Which is ok if it is legitimate. I don't agree that in order to understand physics, on any level, it takes a profound knowledge and working experience in mathematics. To break new ground you probably need those resources but once it is thoroughly worked out, like quantum physics, unlike string theory, it takes a little generosity and time by clear thinking individuals. For instance, the explanation given about why renormalization seemed "dippy" to Feynman. Excellent picture, positively exciting. But for the snobs that are little overly expressed with their mathematical prowess remember you did not invent this math you simply learned how to regurgitate it,( and possibly use it to a minor degree).

 

[Buckeye]

I am a little surprised how sensitive the physicists are to a little questioning of what they so thoroughly believe in. I don't find Buckeye's questions particularly aggressive. As a matter of fact I think similarly sometimes about how physicist attack and explain phenomena. I hate to break it to you but it seems a little closed to outsiders. Which is ok if it is legitimate. I don't agree that in order to understand physics, on any level, it takes a profound knowledge and working experience in mathematics. To break new ground you probably need those resources but once it is thoroughly worked out, like quantum physics, unlike string theory, it takes a little generosity and time by clear thinking individuals. For instance, the explanation given about why renormalization seemed "dippy" to Feynman. Excellent picture, positively exciting. But for the snobs that are little overly expressed with their mathematical prowess remember you did not invent this math you simply learned how to regurgitate it,( and possibly use it to a minor degree).

If you hang around a while, and put on your Teflon coated shoulder pads, you should see that it is only the younger ones who are sensitive to the questioning of their faith and their 4-8 years of learning how to properly regurgitate formula.

For me, I find it stimulating to be called on to help others to understand XPS, surface physics, their application and my bold idea on the nature of the electon. If I can not explain something in a simple manner to a beginner then it means I don't fully grasp the concepts, the physics or the electron-optics etc. It means I need more practice at explaining the basics and kinematics before I can attempt to justify the theory.

Such is life. Full of challenges.

Oh, I forgot to mention that Milawi and Humanino have been following my posts quite energetically. Perhaps, for the reasons you stated above.

 

[Buckeye]

By the way, guys and gals.
Feynman published his QED book, with the "dippy" statement in 1985, just a little more than 20 years ago.

Has advanced physics really advance that much over the past 20 yrs?

 

[humanino]

Was it really Albert or his 1st wife who developed most of the theory of Albert's first 3 papers?

It was Riemann and Hilbert. Indeed, you need to buy a math book.

 

[humanino]

Has advanced physics really advance that much over the past 20 yrs?

Physics advances as we loose our time "discussing" here.

 

[malawi_glenn]

Normouse: The thing is that he claims that he knows much, but he doesn't. He is already convinced that the physical paradigm of today is wrong. He is not even a physicist. It would be different if it were a person who just started college and had a bunch of questions. But this guy is working on his own (crackpot) theories, without even knowing what the heck is is refusing.

Buckeye:
What if the physics of a process CAN'T be explained to a beginner?

As we have written here quite a lot now, it doesen't matter if Feynman would have published his text 3years ago (if he was alive). Physics don't follow prophets.. Einstein never believed in quantum physics, Fred Hoyle never believed in the Big Bang. And so on..

A possible explination can be that Feynman never read articles after the 1970's, or just wasn't smart enough to understand what he read. I have one professor in particle physics who thinks Supersymmetry is junk. And another professor who believe very strongly in it. That is why consensus is important. You can't use your authority all the time.

 

[Buckeye]

Physics advances as we loose our time "discussing" here.

No one forces you to respond, so why do you?

 

[Buckeye]

Normouse: The thing is that he claims that he knows much, but he doesn't. He is already convinced that the physical paradigm of today is wrong. He is not even a physicist. It would be different if it were a person who just started college and had a bunch of questions. But this guy is working on his own (crackpot) theories, without even knowing what the heck is is refusing.

Buckeye:
What if the physics of a process CAN'T be explained to a beginner?

As we have written here quite a lot now, it doesen't matter if Feynman would have published his text 3years ago (if he was alive). Physics don't follow prophets.. Einstein never believed in quantum physics, Fred Hoyle never believed in the Big Bang. And so on..

A possible explination can be that Feynman never read articles after the 1970's, or just wasn't smart enough to understand what he read. I have one professor in particle physics who thinks Supersymmetry is junk. And another professor who believe very strongly in it. That is why consensus is important. You can't use your authority all the time.

Pray tell me, where did I claim to know much?
Yes, I believe there are some fundamental problems that are blocking our progress. Would you believe that I even have doubts about Coulomb's results, the repulsive nature of like particles, Newton's law of gravitation? Surely, this is blasphemy, and I should be hung out to dry.

Now it seems you are belittling Feynman where I did not. You seem to be belittling Einstein and Hoyle. Why?

Consensus is the reason why all the lemmings jumped off the white cliffs of Dover as the Piped Piper played his merry tune, or, as least, that's how the adage goes. Me, I prefer to think for myself, and to ask others for responses to my questions when I am unsure of my reading.

Oh, I forgot. If you can't explain the physics of a process to a beginner, then I suggest that you never become a teacher, professor, manager or director.

 

[Buckeye]

I knew you were being sarcastic, and I think your argument is rather ignorant. You don't have to know _everything_ about something in order to gain value from it. Renormalization is taught because it provides very accurate, very useful results and predictions. We know some other theory will supercede it, just as all theories are eventually superceded. You can't be so childishly dismissive of something that's been so successful if you don't have a better alternative. And your analogy to teaching that the Earth is flat is completely wrong: in fact, a "flat" Earth is immensly useful for certain types of cartography. Should we eliminate the use of mercator projections and the like because they're not perfect?

FEYNMAN has standing to call renormalization "dippy". No one on this forum does, however.

By supercede, do you mean move forward with a better math argument?
What do we do, if the right answer, requires that we go back to the fundamentals and fix some concepts that are wrong, but our math allowed us to move ahead, despite the error?

I agree 100%. Feynman has the standing. Just like M. Kaku has the standing to say that QFT has its problems and that string theory has its problems.

Yes, teaching renormalization is useful as long as the proper warnings and limitations are also taught so someone in the future will have the good sense to question infinity / infinity = 1. I'm not sure, but it seems as though my question may have led you to call me "childishly dismissive"? Is that about right?

 

[malawi_glenn]

You claimed that you had read 80books cover to cover, that is more than I've ever did ;)

The thing is that a person can't be an expert on everything. Einstein was the father of theory of relativity, and one of the most important physicsts ever lived. Hoyle was the father of nuclear astrophysics, but we can't say that since he said that Big Bang is junk, big bang IS junk.

This is an old Swedish wisdom word:

"Thinking free is great, thinking right is greater"

 

[Buckeye]

Renormalization was weird when it first came out back in the day, but the mystery was largely resolved in the 70s with the advent of the renormalization group and lattice gauge theory. It seems perfectly natural now and it would be weird if you *didn't* have to perform such a process.

Hmmm,
That's strange. Does that mean that Feymann, in his 1985 book on QED, did not know that renormalization and lattice gauge theory in the 70s contradicted his writing in 1985, or was he still at odds with renormalization?

 

[Normouse]

Time for alarm

I have no illusions,(not too many). I know that I am a fiesty third-grader in the ring with Mike Tyson but one hopes that he would be too embarrassed to take my head off. But I am mildly alarmed that Physics has turned into a new form of mathematics(extremely wide ranging and complex) with a lab. That lab is reality. Mentioned in the thread was science was to be able to calculate and predict tangibly the results of experiments. Who said that? Did God whisper in someone ear when I wasn't looking. Why is science only that? What about non-mathematical insights? What about intuition,(non-mathematical)? Unless you know the math completely, not much of those things are around even mathematically. Are we going toward a mathematical wall where only the inventors of the new mathematics can conceptualize Physics? Unless you professional boxers are willing to share a little and value visualization of reality a little more we amateurs will be totally left out. We then have no choice but to come up with our own theories, which some of you ungraciously call "crackpot" just to participate. Cut a brother a break.

 

[Haelfix]

Buckeye, the difference is renormalization gives experimental agreement in hundreds of thousands of experiments that take place daily, to fantastic accuracy. Be sure its a working mechanism, whether its particle physics or condensed matter.

When mathematicians catch up (and they will, as they already have in 3d toy models) all that will happen is they will say 'ok we've proved renormalization 100% rigorously in the continuum, infinite volume limit '. They might even tell us something we don't already know, but they won't contradict the results we do predict and have measured.

Its really no different than when Dirac invented a fictitious function (the delta function), which took a couple decades before the theory of distributions made it rigorous.

Anyway this discussion is boring, since there is absolutely no specifics about exactly what you don't like. I'll finish by pointing out lattice gauge theory is a perfectly rigorous mathematical construct. It is by its nature a controlled approximation, so you need numerical methods to deal with it, but that's fine. And I have no idea what Feynman thought in the early 80s. Most of us have a more thorough understanding of field theory than he did, since we've benifited from nearly thirty years of collective work by thousands of physicists that he never had access too.

 

[malawi_glenn]

Normouse: Physics and math has always have a strong relationship. The inventors of the math we use today (calculus etc) was also natural scientists. It is just natural, if the world is rational and logical, then one needs a rational and logical way to describe it.

I don't complain that I have to study intro chemistry in 3 years in order to understand DNA. I try to find what my talents are and try to improve them. If math isn't your thing - then either practice more or try another thing.

 

[Haelfix]

Normouse, unfortunately advanced physics requires a lot of sophisticated mathematics. Intuition does play a role, but its much more subtle than what a layman can expect to understand.

Thats just the way nature is, and alas there is probably nothing that can be done about it (thank Einstein and the founders of qm for their wonderfully unintuitive yet valid insights). Fortunately all this stuff is available in the public domain, so if you do take the pain to learn it, it does indeed make perfect logical sense in the end.

I do know people who have a decent understanding of this stuff who learned it from scratch without the aid of a university or classes, so it is possible.

 

[malawi_glenn]

Hmmm,
That's strange. Does that mean that Feymann, in his 1985 book on QED, did not know that renormalization and lattice gauge theory in the 70s contradicted his writing in 1985, or was he still at odds with renormalization?

Those are two options yes.

I must ask you one thing, you wants to think on your own, but you put a lot of emphasis on persons who are regarded as 'legends' when they agree with you. We who are physicsists knows that we don't follow prophets.

 

[vanesch]

Yes, teaching renormalization is useful as long as the proper warnings and limitations are also taught so someone in the future will have the good sense to question infinity / infinity = 1. I'm not sure, but it seems as though my question may have led you to call me "childishly dismissive"? Is that about right?

I don't know if you read my earlier post in this thread. The "proper warnings and limitations" are inherent in ANY scientific activity, and good science students (should) know that. Nothing in science is "true" or is "right". In fact, it is generally accepted by, I would guess 95% or more, of the particle physicist community that the standard model is "ultimately wrong". I don't think there are many particle physicists out there who think that the standard model is the "correct description of nature" - there are indeed many reasons for people to think that it is not, and renormalization is one of them (although not for the reasons you think it is).

But what counts in science is whether it WORKS (not whether it is "true"). Many people don't understand this, they think that science is an endeavor like religion which looks for "the ultimate truth". Even some scientists as of today make that error (the "theory of everything" and other nonsense).

This is why I lined out that the science of "the flat earth" is good science when looking at a local map, or building a house, or things like that.

Another remark is that especially physicists often use "erroneous math" which works, to find out later that one can make the mathematics fully rigorous. Of course, there's a danger that one really makes mistakes that way. But as long as it *works*, that's no problem. A historical example was Heaviside, who invented a lot of improper functions used in electrical engineering (the "Dirac deltafunction" etc...). Heaviside's way of doing is still taught in electrical engineering, even though it "doesn't make sense that way" to a mathematician. But (long after Heaviside) mathematicians invented a theory (the theory of distributions) which DOES allow one to use equivalent mathematical objects as Heaviside used intuitively, and where one can rigorously show that the calculational techniques used by Heaviside DO give correct results (even though the way it is done is not "correct"). But most electrical engineers don't bother with this more involved way of exact maths, they use the Heaviside way of doing things, knowing that they will obtain correct results (the same results they would obtain if they did it "correctly" in distribution theory).

 

[vanesch]

But I am mildly alarmed that Physics has turned into a new form of mathematics(extremely wide ranging and complex) with a lab.

That's the *definition* of physics: how mathematics applies to observations of nature! If it has no mathematical underpinning, it is not physics. It is not possible to do physics without some form of mathematics. Now, that mathematics can be approximative, and one can use intuition instead of calculations, but it is still "mathematics". For instance, saying that "pressure rises with the amount of gas in a container" is still a mathematical statement (even though it is not an equation, it specifies something about the functional relationship between two quantities (real numbers).

That lab is reality. Mentioned in the thread was science was to be able to calculate and predict tangibly the results of experiments. Who said that? Did God whisper in someone ear when I wasn't looking. Why is science only that? What about non-mathematical insights?

Well, unfortunately, that IS science. Science is the confrontation of a theory (a set of hypotheses, with their logical, hence mathematical, deductions) with observations (hence some form of quantitative assessment).
You cannot confront these if there's not some form of mathematical relationship between quantities (even inprecise, as stated above). And if you cannot confront them, then the theory is "non-falsifiable" and hence "non-scientific".

It's the very definition of science.

What about intuition,(non-mathematical)? Unless you know the math completely, not much of those things are around even mathematically. Are we going toward a mathematical wall where only the inventors of the new mathematics can conceptualize Physics?

No, you can use old mathematics too, with new hypotheses.

Unless you professional boxers are willing to share a little and value visualization of reality a little more we amateurs will be totally left out. We then have no choice but to come up with our own theories, which some of you ungraciously call "crackpot" just to participate. Cut a brother a break.

But that's about as interesting as saying that "you professional scribes should be willing to let us, who have never learned the alphabet or any grammar or vocabulary, also write our works of literary art...", in other words, you should also consider our meaningless scribbles on paper.

 

[Son Goku]

Hmmm,
That's strange. Does that mean that Feymann, in his 1985 book on QED, did not know that renormalization and lattice gauge theory in the 70s contradicted his writing in 1985, or was he still at odds with renormalization?

Feynman suspected that Quantum Electrodynamics did not make sense in a purely mathematical way. It is fantastic as a physical theory. Also, lattice gauge theory wasn't really around in the 1980s.

There is significant evidence that quantum electrodynamics doesn't make sense as a mathematical structure, unlike quantum chromodynamics which probably does make sense.
However this is a very technical issue.

 

[Normouse]

Whoa ego!

That's the *definition* of physics: how mathematics applies to observations of nature! If it has no mathematical underpinning, it is not physics. It is not possible to do physics without some form of mathematics. Now, that mathematics can be approximative, and one can use intuition instead of calculations, but it is still "mathematics". For instance, saying that "pressure rises with the amount of gas in a container" is still a mathematical statement (even though it is not an equation, it specifies something about the functional relationship between two quantities (real numbers).



Well, unfortunately, that IS science. Science is the confrontation of a theory (a set of hypotheses, with their logical, hence mathematical, deductions) with observations (hence some form of quantitative assessment).
You cannot confront these if there's not some form of mathematical relationship between quantities (even inprecise, as stated above). And if you cannot confront them, then the theory is "non-falsifiable" and hence "non-scientific".

It's the very definition of science.



No, you can use old mathematics too, with new hypotheses.



But that's about as interesting as saying that "you professional scribes should be willing to let us, who have never learned the alphabet or any grammar or vocabulary, also write our works of literary art...", in other words, you should also consider our meaningless scribbles on paper.

No, Wrong. I realize you have to have a least modest of confidence to tackle this mathematics but perhaps you should examine your way of expressing your ideas. Just because you put things in capital, by the way the rules say that is "shouting" and therefore rude, it isn't necessarily anymore true than when you write in lower case. Your judgment seems to be a little clouded by your occupation. None of you, or very small percentage, will even be able to conceive that notion. Back to the analogy. It's not that we haven't learned the alphabet or the grammar but that we haven't read Proust or Tolstoy yet. That doesn't mean we are illiterate. And furthermore your analogy fails again by calling what we write meaningless scribbles. Let me reminder you again that Einstein's theories were considered "meaningless scribbles" until he got lucky or should I say we got lucky and had it confirmed in a unlikely way in South America. Is the underlying idea here exclusivity? I'm beginning to wonder. Also the lecture about mathematics being the underpinning of physics is "silly" and a little condescending. My yellow lab "ginger" knows that. (She,s a pretty smart dog.) Please read a little more subtlety into the responses please.

 

[Doc Al]

A profoundly empty response.

This thread is going nowhere. Closed.