How to explain the benefits of string theory to my grandmother

[chrisina]

(in the first video, the most interesting starts in my view at about the 20th min.)

 

[rewebster]

First of all, to mjsd, no, my grandmother was not being cynical, but genuinely interested in the question. I had just shown her this "elegant universe" TV show that I found via this forum. The thing, you should meet my grandma, she's going on her 95th birthday but is still very alert and loves to keep up to date ... maybe the fact that, as a young woman she was between 1932 and 1939 the secretary of a certain Louis de Broglie at the Paris University is for something...
Secondly, I do not buy in the "fun / sexiness" arguments. I am passionately convinced that we are living some of the most exciting years in Physics since the 1920s, because there seems to be so much we need to understand again. I mean so much Fundamental we need to understand.

Hey---

---YOU haven't answered MY questions first!---did granma REALLY work for de Broglie ?------AND does she have any juicy* stories about the times there that she is WILLING to share (or unwilling even)?

-------------------------

juicy*----I mean, related to PHYSICS, of course

 

[chrisina]

no, I'm not joking, she really worked for him before the war.
She wasn't a Physicist, she was only his secretary. De Broglie didn't speak good English, so she had to translate all the time.
Those days, De Broglie was organising a regular seminar in Paris on what was then called wave mechanics. In this context, she remembers meeting with most of the greatest names of this century (Einstein, Heisenberg, Pauli, Schrödinger,Born, Fermi...etc). What was clear to her then, was how De Broglie and Einstein were so close (from a frienship and philosophical standpoint) and shared the same views on causality / determinism. They were always in one camp in the debates, against all the others.
It's strange in a way that this debate is still not over now, especially when you look at the current debate between people like Smolin / Rovelli and people like Süsskind / Polchinski on Background independence or not.

 

[rewebster]

Well, just a suggestion along this thing---I would get all the memories of everything that she can remember (set up a video camera as a type of video diary) --as she recalls different things over the next months. There's not too many people left in the world that have been in her situation and it would be a great loss to you (and all of us) if it isn't recorded for history.

 

[Fra]

I think Chrisina has some good reflections.

I think that if anyone senses that some proposed ultimate answer doesn't seem to match the ultimate question of their preference, that answer doesn't have very much value from their point of view, even if it is possible to devise a question to which it is the answer.

I have lately had a strong impression that there is something wrong, not only with the theories, but with the application of the scientific method.

When model complexity increases, the number of possible routes of expansion naturally also increases to the point where the originally not very sophisticated guessing routines gets quite inefficient, and the chances are that unless we can evolve some higher level of sophistication to make progress we will die. I think this requires not only looking at new formalisms, but also looking at new methods for looking.

So what is the ultimate tool a lifeform needs? A grand unification of all physical forces in nature? I hardly think that's it, is it? I think we need to revise the questions we are trying to answer.

Experience tells us that usually one answer often results in follow up questions by some desire to reach out further. So the ultimate question seems to be, what the next question should be. Because the response of the first answer is usually another question.

I've been called philosopher a lot but to speak for myself I do not believe in anything such as ridicilous as the ultimate answer, or the ultimate question.

This simply and obvious observation has lead my to think that any candidate GUT that is to make much sense at all, must at least aspire to implement and explain this evolutionary rule, and therefore I think the answer is not a infinite dimensional monster model, I think it is a basic evolutionary rule. At the same it should also be clear that at each level of evolution, there is most certainly possible to find a fixed model that explains everything. But if we have reason to think that new questions will eventually be asked whose answer is outside this model, it should become almost obvious that the larger and more complex the model becomes, the more essential is it that is has the able to respond to this request and evolve accordingly.

So, in addition to the falsification property, I think any sensible theory should at lest TRY to implement an emergency response to the unexpected. At least in my personal quest for scientific answers, I have hard to take anything that ignores this as even possibly fundamental.

All the thinking I've done suggest that these evolutionary ideals is a deep thing, and is far more than just some analogy with biology. I would say it is not really an analogy with biology, except in our heads, it's deeper than that.

This is also something that I think would be understandable to the public.

/Fredrik

 

[chrisina]

cannot agree more with you Fra, evolution seems to be a fundamental aspect of nature that particle physicists and cosmologists have not really taken into account so far... if it applied to organic molecules, why not to the fundamental constituents of our universe ?

I like to study the history of science, there are some jewels :

at the very end of the 19th century, Ludwig Bolzmann was asked "are there things that science still cannot explain ?" He replied, "there are two small things that puzzle me, where does the law of blackbody radiation come from, and why doesn't the Michelson-Morley experiment work"

Well we all know what happened next. These were the two fundamental trigger points which gave birth to most of the 20th century physics.

You see, I'm stuck in the same way of thinking (maybe I should have lived in the 19th century) :

there are two "small" things we do not understand :
1. where do the parameters from the standard model come from,
2. and what is this dark energy / cosmological constant that seems to constitute more than 90% of what the universe is made of.

String theory developed in an attempt to answer question 1, and question 2. was not known at that time.

Now it seems that string theory is saying that the best answer to these questions is a form of quasi infinite landscape of parameters and some form of anthropis explanation.

I am afraid that if we would have invoked the same "anthropic principle" to Ludwig Bolzmann's questions, I wouldn't be typing on this damn computer, because the interent, electronics, etc would not have been invented.

 

[rewebster]

What have you told your grandma so far?


or, Is she a 'classical'/'quantum' woman?

 

[Careful]

I don't know if anyone said this already but first I would explain my grandma about gauge theories which are universally accepted (shut up about the problems in the formulation of a quantum field theory, keep everything on the classical level). Then, I would pick out the solution of the vector potential for a point particle in an external electric field in Lienard Wiechert form, and show her explicitely where hidden strings and two branes can be found. Next, I let her imagine how pure radiation interacting with matter could be seen as scattering of closed strings (on something else) and then I would tell her about the work which has been done in the eighties on string gauge duality and how to derive fermions from bosons (because I don't want to explain her Grassman calculus).

Probably I would first have to tell her about the hypothesis of atomism versus a spacetime field theory though (since I keep everything classical).

 

[Fra]

I went through Smolin's paper on alternatives to the anthropic principle listed by marcus in https://www.physicsforums.com/showthread.php?t=166703 and while I think he has som good points, I can help finishing the paper very unsatisfied.

I sense there is a very categorical tone of reasoning, and that some things are simply true and some are false, based on not crystal clear reasoning. I would have thought that modern physiscs should have suggested that the better way of reason is to consider degrees of truth. Where complete certainty and complete uncertainty are really only extremals, and these extremals is almost all you've got back in the classical world. For various reaasons, for example finite resolution of measurement and finite data storage, I think it doesn't make sense to reduce the degrees of support to true and false. Moreoever, I think it should also seem clear that degrees of truth can be relative, or subjective if you want. This makes me doubtful about Smolins categorical use of the term "shared evidence" because upon closer investigation in my opinion at least, this is not as easily defined as in classical world.

/Fredrik

 

[Fra]

The main problem I have with the categorical reasoning is that it risks overseeing other seemingly "unlikley" (but still possible) possibilities, that in the boolean reasoning are simply taken to be false.

/Fredrik

 

[Demystifier]

... evolution seems to be a fundamental aspect of nature that particle physicists and cosmologists have not really taken into account so far... if it applied to organic molecules, why not to the fundamental constituents of our universe ?

Because they are, by assumption, fundamental. Unless you think that "fundamental" constituents are not really so fundamental?

 

[chrisina]

but isn't that precisely the idea behind trying to find some logic in the whole "zoo" of of particles in the standard model ?

There might be no logic, I agree, but that statement should not stop people from trying to find one... We might discover something, in the same way as we discovered something when we tried to explain the periodic table of elements.

I'll be away for a couple of weeks...

 

[chrisina]

and by the way, I'm more and more inclined to believe that the key lies in our understanding of the vacuum.
This is just a crackpot hypothesis, I know, but maybe one day someone will come up with a model for the vacuum which will explain the "zoo", the uncertainty principle, and the foundations of GR.
And I bet it will be some form of deterministic system and will entail dimension reduction, not augmentation.

Just a bet, who wants to take it ?

In that line, there's one paper I love from G. 't Hooft

gr-qc/9903084 "quantum gravity as a dissipative deterministic system"

BTW, the latest paper by E. Witten (see other thread by Ensabah 6) seems that more people are looking in what happens when one simplifies GR and looks at it in 2+1 dimensions.

The question will of course be, if something comes out of this, how to derive from this a model for the real world (3+1). But let's wait and see, I'm inclined to think that it is a new direction, and certainly opposite to the old ST multiplication of solutions.

 

[Fra]

Because they are, by assumption, fundamental. Unless you think that "fundamental" constituents are not really so fundamental?

IMO, there is at least a certain way they are not "fundamental".

IMO the "fundamental" constitutents are IMO, first of all, really a part of of our model, our best understanding of how things seem to work. We like to think that this models reflects the true nature of things, but the real question is, what is the difference between the nature of things and our best knowledge of how things seems to behave. Because the fundamental thing here is IMO, is that whatever the "nature of things is", it is not given to us. We have to learn, and find out. The truth is not given to use, it's something we apparently acquire or "find out". And this the process of "finding out" - the scientific process - can at least IMHO not be trivially separated from the result.

Understandings tend to improve, and what was believe to be fundamental several thousand years ago, is not considered to be fundamental today. And finally the point would be that even if some constitutiens ARE fundamental - what is the sense in such a statement until we have acquired support for it? It's simply not there.

So IMO the better attitude is to consider expected fundamental constitutents. But we should have learned the lession that expectations tend to change, so I would be reluctact to carve anything in stone.

I suspect that some may feel the above argumentation seems to much hung up on "human understanding" but this is not necessarily so, because the idea is that there is close analogies and similarities with learning processes and physical processes.

This is why I personally take the attitude that the fundamental "constituents" are not irreducible facts, but rather the rule how we arrive by reasoning to this _supposed_ irreducible facts.

That is not perfect and foolproof, but I do not see a better way (atm) to the limit of my current understanding. That's all I'm asking of myself. In either case I can't stretch myself to ignore the possibility that even the to mankind best scientific knowledge of what is fundamental and is not, may come to be revised, as many times before.

/Fredrik

 

[Fra]

I'm more and more inclined to believe that the key lies in our understanding of the vacuum.
This is just a crackpot hypothesis, I know, but maybe one day someone will come up with a model for the vacuum which will explain the "zoo", the uncertainty principle, and the foundations of GR.
And I bet it will be some form of deterministic system and will entail dimension reduction, not augmentation.

Just a bet, who wants to take it ?

I agree that the "vacuum" is very interesting and is probably a key focus point. The critical scientific reasoning should also be applied to the vacuum. It seems "nothing" is not so innocent what you try to define the question better. The fact that we ask questions about vacuum seems to suggest that there is at minimum a connection to the questioner. A "vacuum" that has any meaning whatsoever to us, must have a connection to us, like a boundary. So it seems the qualifying support for the vacuum itself must emerge from the boundaries. To just picture complete vacuum with no boundaris and no interacting observer seems very ambigous. There is always a faint connection, or the question would hardly have appeared. At least I could't picture how.

/Fredrik

 

[rewebster]

Now---There's two terms that seem to be at the heart of the matter:


Logic

&

String/MWI theory



Two definitions of logic here?:

logic = a type of philosophy

or

logic = using math

(term usage: something seems to have happened about mid-century with the term 'logic' + and the 'math' of computers gaining prominence to push the 'term' 'logic' more toward a 'math' definition)



I know for myself that it (logic) SHOULD be some (a compatible level) combination of both (reasoning and possibilities).
---------------------------
String/MWI theorists would really, REALLY like their theory to be FUNDEMENTAL. Green's NOVA broadcast tried to push that thought through. ('did everyone buy the book right after the broadcast?', some 'anonymous' person asks.

 

[rewebster]

What percentage (0%-> 100%) do you (as personal opinions) assign to the logic (reasoning) and to the logic (math) of string/MWI theory, where the total of the two totals 100%?

-----------------------------------
For me:



logic (reasoning)= 5%

logic (math)= 95%

nb: not understanding some/all the math (for me) of string decreases the 'logic (reasoning)=' number.

 

[Fra]

IMO, mathematics has been the language of preference for any "theory" that is to make quantitative predictions, may it be physics, economy or many other things, because it's hard to quantify something without ending up inventing some kind of number system, and all the other stuff that unevitably follows from applying that. So to be into that business without at least some minimum of skills on the tools, makes it a lot harder. So math is good and necessary at least from an effective point of view.

However I think there is a substantial difference between understanding the language, and understanding whatever you are trying to say using that language. Neither do I think you need to be a math professor to have an opinion on string theory. Perhaps that explains my position.

It seems that the need to express something, often drives the development of tools and new formalisms and tools. But for me the tools has their main justification in the very questions they were originally designed to answer.

To apply a given well known and working theory, that's "applied science" to me. To learn how to use a given, and proven tool, is something different than reasoning why we need to invent new tools. And the inventive process is different than the application process.

In the inventive case I'd obviously put a massive emphasis on logical reasoning. But even in the process of reasoning mathematics is sometimes a tool.

Sometimes different tasks may have differently tools of choice, or perhaps sometimes some things can be done with different choices of tools. But it seems to be sometimes, certains tools are simply outperforming other tools in terms of effiency for certain tasks. This can be both in favour and in disfavour of math. Sometimes plain english outperforms symbolic math, in several ways, but more often in physics the opposite seems true.

Some people often argue that physics is just hard math, and everything else is just philosophy that leads nowhere. I couldn't disagree more with that attitude.

So I agree we need both. About the percentages I think I could put almost any numbers there, and find a way to defend it, depending on how the question is interpreted.

/Fredrik

 

[Fra]

I often find myself experiencing the almost paradoxal (though it's not really a paradox) situation that sometimes overly stringent and "narrow minded" formalisms may prevent you from even understanding a new questions. You simply don't see it, because what is outside the defined language, is by definition not "heard", it's silently disposed of as noise. You need to shutdown the anality and try to be more sensitive to even the most fuzzy apperances, before the question is understood, but then, in the process of answering the question, I often find myself, refining the question and eventually rediscovering a need to sharpen the view into a more "narrow minded" search again to find an (answer,question) set that is to satisfaction.

OTOH getting stuck in the wide but low res mode, may not yield satisfactory answers to any questions. Because the resolution in the language is too poor.

/Fredrik

 

[rewebster]

IMO, mathematics has been the language of preference for any "theory" that is to make quantitative predictions, may it be physics, economy or many other things, because it's hard to quantify something without ending up inventing some kind of number system, and all the other stuff that unevitably follows from applying that. So to be into that business without at least some minimum of skills on the tools, makes it a lot harder. So math is good and necessary at least from an effective point of view.

However I think there is a substantial difference between understanding the language, and understanding whatever you are trying to say using that language. Neither do I think you need to be a math professor to have an opinion on string theory. Perhaps that explains my position.

It seems that the need to express something, often drives the development of tools and new formalisms and tools. But for me the tools has their main justification in the very questions they were originally designed to answer.

To apply a given well known and working theory, that's "applied science" to me. To learn how to use a given, and proven tool, is something different than reasoning why we need to invent new tools. And the inventive process is different than the application process.

In the inventive case I'd obviously put a massive emphasis on logical reasoning. But even in the process of reasoning mathematics is sometimes a tool.
Sometimes different tasks may have differently tools of choice, or perhaps sometimes some things can be done with different choices of tools. But it seems to be sometimes, certains tools are simply outperforming other tools in terms of effiency for certain tasks. This can be both in favour and in disfavour of math. Sometimes plain english outperforms symbolic math, in several ways, but more often in physics the opposite seems true.

Some people often argue that physics is just hard math, and everything else is just philosophy that leads nowhere. I couldn't disagree more with that attitude.

So I agree we need both. About the percentages I think I could put almost any numbers there, and find a way to defend it, depending on how the question is interpreted.
/Fredrik

1) yes--absolutely

2) invention/discovery always comes first

3) I'm just asking your opinion (for placing the percentages) --not to be etched in stone

-----------------------------------------

and try to be more sensitive to even the most fuzzy apperances, before the question is understood,

sort of like those 'fuzzy stars' from before the 1920's or 1930's

 

[Fra]

3) I'm just asking your opinion (for placing the percentages) --not to be etched in stone

I figured that, but the above was my version of the answer :) But to give numbers how about

logic (reasoning)= 95% / logic (math)= 5%, during the early phase where the theory is nothing but a speculation on a fuzzy question, because in this early stage I think more effort should be spent on trying to understand what we are doing and what options we have...

...but suppose in the future IF this theory is largely supported by more experiment and finally ends upp accepted as a working TOOL, then most of the fuzzy is resolved already, and hopefully transladed into computational schemes... so in this later - mature state, I think perhaps one can axiomatize it and then perhaps logic (reasoning)= 5% / logic (math)= 95% seems more reasoanble.

As for right now, at least I've got a feeling that the early part has been rushed over, in eager to dig into juicy math. So I would personally like to see more reasoning, than what is typically seen.

/Fredrik

 

[rewebster]

Now, there's something 'metaphysical/paranormal'---the last few posts of this thread disappeared

---------oops different thread--never mind

 

[rewebster]

and by the way, I'm more and more inclined to believe that the key lies in our understanding of the vacuum.
This is just a crackpot hypothesis, I know, but maybe one day someone will come up with a model for the vacuum which will explain the "zoo", the uncertainty principle, and the foundations of GR.
And I bet it will be some form of deterministic system and will entail dimension reduction, not augmentation.

Just a bet, who wants to take it ?

In that line, there's one paper I love from G. 't Hooft

gr-qc/9903084 "quantum gravity as a dissipative deterministic system"

BTW, the latest paper by E. Witten (see other thread by Ensabah 6) seems that more people are looking in what happens when one simplifies GR and looks at it in 2+1 dimensions.

The question will of course be, if something comes out of this, how to derive from this a model for the real world (3+1). But let's wait and see, I'm inclined to think that it is a new direction, and certainly opposite to the old ST multiplication of solutions.

Define the BET a little more (since you initiated it)---and what the 'prize' for winning will be


--------------------------------------

Most ideas from theories, even relativity, can be usually 'translated' into a layman's language with 'illustrations' and 'analogies'. They may not be prefect in 'translation' , but even when Green 'tried' to animate strings in 'El.. Uni..', it (string) seemed like all the best they could do was similar to a piece of spaghetti bouncing around on a trampoline.

(I kept looking around for the fork to appear)