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Don Lincoln on superstrings

Fermilab's talking head, Don Lincoln, has recorded numerous videos on cool physical topics so it shouldn't be surprising that he has added the coolest topic of all as well, superstrings.



This 8-minute video begins with the classification of elementary particles in the Standard Model, says that the list of ingredients is messy, and argues that there should be a simpler picture. Superstrings represent particles of different species as different "Chladni patterns" of white powder on a speaker. He mentions that the real superstrings vibrate in 11 spacetime dimensions – well, there are no 1-dimensional strings in 11 dimensions (in M-theory) but I don't want to be picky here. ;-)




Lincoln says that the theory is totally "cool" but you should "not believe it" because there is "zero evidence".




I understand the sociological perspective from which these proclamations are fair and balanced. After all, many string theorists like to say the same thing. On the other hand, I still do find this fair and balanced picture irrational.

A rational person believes something if the probability that it is valid obtained by rational arguments is greater than (or much greater than) 50 percent. In science, the rational arguments always rely on some empirical input at the end. But the way how the empirical input is used to decide about the fate of theories is always indirect to some extent – it is either slightly indirect or very indirect, the arguments rely on lots of complicated gadgets and/or lots of mathematics or a small amount of those intermediate agents.

When it comes to these epistemic principles, string theory doesn't differ in any qualitative way from quantum field theory – or from simpler theories, for that matter. So saying that one "should not believe" string theory is about as reasonable or, more realistically, as unreasonable as saying that one "should not believe" quantum field theory or general relativity.

They're just two frameworks that boast the explanatory power to explain all the observations we have ever made. They are really competitors of one another. Quantum field theory uses a language that is closer to what we immediately observe. After all, effective quantum field theory is directly constructed to contain all the relevant objects and processes at a given length scale.

But the fundamental theory of the Universe doesn't have any reason to use a language that is close to some mundane scale of 21st century experiments. Another advantage of quantum field theory is that we know rather clearly how we should adjust its list of fields, particles, and interactions to yield a model (the Standard Model) that immediately describes the observations; in string theory, we have many rather different compactifications to produce a realistic vacuum.

Nevertheless, when we compare the two competitors according to any other feature, string theory has a smaller or larger edge in comparison with quantum field theory.

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reader Dilaton said...

I hope I will see the cute little kitty string-theorist at work too, when I'll watch the video at home ... :-)


reader physicsnut said...

I was reading the Polyakov article in "50 years of Yang-Mills"
and he notes a few string applications, but sounds like a moderate about it.


reader Don said...

Hermann Weyl would agree with this very much. The link with experience is much more theory-dependent than people nowadays seem to appreciate. Weyl explains how even the concept of "mass" refers to something we never sense or experience. Mass is only a theoretical concept, an essential part of a theoretical framework used to calculate consequences in terms of things we can sense, such as movements of different types (inertial, accelerating, etc).

WE DO NOT SENSE MASS!! We are only aware of the various qualities of our perceptions. Mass is not one of those qualities. We only infer it's existence indirectly via theories.

People today seem to be too literal minded and have forgotten that the theory sets the terms in which any experiment is interpreted. There are no "facts", really. Just points where experience and theory overlap, which points are generally few and far between, as you insinuate by the term "indirect".

I think this lack of philosophical nuance plays some role how things seem to be stalled today. At the beginning of the 20th century, people were entertaining a diversity of interrelated questions like: (1) what does it mean to be objective? (2) what is math? (e.g. Hilbert vs Brower), (3) what is measurement and how does it relate to the qualities of perception?, and so on. Both QM and Relativity emerged from considering such issues.

The result were two new formalisms. One formalism said measurement had to account for noncommuting properties, which previously did not need to be considered. The other, Relativity, led to a much more nuanced handling of geometry as an accounting device, basically saying we could not assume Euclidean geometry was an adequate accounting device.

Both cases seem to amount to more refined accounting devices. But it seems to me that people have, in some sense, mythologized the qualitative content of QM and Relativity, got all caught up in "magical" things like the double slit experiment, or the twin paradox, etc. but forgot the basic fact that QM and Relativity are really just forms of accounting necessitated by more refined ways to interpret our sensory experience.

Weyl did not "believe" in facts. He called Nature the "transcendental" in references to Kant's idea that we can never know a "thing in itself". We cannot know what is outside of our mind. Weyl accepted this and concluded all we can do is try to construct self-consistent accounting devices (e.g. models) and look for special points in our sensory experience where we can measure some aspect of the model to test the accounting scheme.

I think this was Weyl's equivalent to Bohr's pragmatism. Both had, in their own ways, relinquished the classical idea that our mind can know the truth of "nature". This seems to have been forgotten. People today have reverted back to thinking that there is some objective reality that our mind perceives and that the math is supposed to capture. I think this is a regression.

Thank you, Sir, for the opportunity to express these ideas.

Best wishes,
Don


reader lucy loo said...

Dea Lubos – It’s so very
disheartening to reaId some of this from you. What you say looks just like what
all the other fields are trying to saay as well. That prediction has no real distinctiveness
and science will work just as well without it, due to rational argument. you really be this misconceived about Science?

Predictions are a basic expectation. If there’s a new theory that
goes further than the incumbent, presumably it has something new to tell us
about objective reality? Ancd that’s just another way of describing a
prediction.

Prediction events are
overwhelmingly the dynamic by which robust knowledge extends. Abstract theories
get accepted for good predictions. Down the line the abstract theory is
replaced with a better one. But the robust knowledge arising when the
prediction gets confirmed, sticks around a lot longer.

Prediction events are
also the bridge from science to engineering and technology. All the paradigm
shifting breakthrough theories of sciencie so far, have given rise to
equivalent revolutions across engineering, technology and the economy. Typically a new way to
understand energy and a new way to tap that energy arises from these events.
These events are nothing other than the most precise most powerful prediction
events Science produces. E.g. V=IR….every single time an electric circuit
performs exactly as theory requires…a huge precise prediction is in play. That
gets corroborated.

What you are saying above amounts to
arguing for a ‘new kind’ of sciene, that never again produces energy
revolutions. Without predictions Science is nothing but explanations.
Philosophy in other words. And how much have they produced?


reader pEGO said...

I am working on Calabi Yau see picture below.

https://petervesely.files.wordpress.com/2015/01/calabi-yau-build-string-theory-cold-fusion.jpg

Formula of Calabi Yau is too robust and for thousand of pages, there is not math for humans due to too robust calculations.
I developed new kind of fractal RTDG, that is computer algorithm based on simulation physics of light near perfect realism, that could calculate it. I am working on Calabi Yau with them, please see below picture. String theory is unifaction theory of field and my preliminary calculations say that include
also gravity.

Aim of my work is use it for cold fusion reactor based on vacuum polarisation during this phenomenon photons break
down to electron-positron pairs they split and produce energy.

Preliminary
calculation below link

https://petervesely.files.wordpress.com/2012/08/cold-fusion-premilinary-calculation-fractal-rtdg.jpg


MY COLD FUSION Reactor
progress:

PRINCIPLE ↓

PHOTONS “shots” (I am preparing math mechanism for that) into vacuum (there is boiling in vacuum — creating and destroying particles, there is enough energy for “changing” so elementary particles like Photons into electron-positron
pairs, scientific article below link regarding light particles of supernova SN 1987A arrived 4.7 hours later than expected, say
there is possible) then “changing” into electron-positron pairs and they anhilate therefore I am calling it Cold fusion reactor because this event is at room temperature.

This phenomenon already has occured in nature, when light
particles of supernova SN 1987A arrived 4.7 hours later than expected
(below link ↓ )

http://www.dailymail.co.uk/sciencetech/article-2672092/Was-Einstein-wrong-Controversial-theory-suggests-speed-light-SLOWER-thought.html

MY COLD FUSION reactor preliminary CALCULATIONS ↓
based on Photoelectric effect

http://petervesely.files.wordpress.com/2014/10/cold-fusion-premilinary-calculation-fractal-rtdg.jpg?w=788

GRAPHs


Mapping of Photons v.01 comparison to NASA photo of cluster from
which X-Ray possible produced by sterile neutrinos were observed

http://petervesely.files.wordpress.com/2014/10/cold-fusion-reactor-mapping-of-photons-v01-comparison-to-x-rays-possible-produced-by-sterile-neutrinos-nasa-fractal-rtdg.jpg?w=788

Electron magnetic field (looks like that of bar magnet 8 )

http://petervesely.files.wordpress.com/2014/10/electron-cold-fusion-reactor-fractal-rtdg.jpg?w=788

This is field model generated from fractal RTDG HeSPe v03. Transform show us the actual transition of waveform in space. Green -Red colors are show EM field surrounding Photon and changing field at time. Other colors show us intergration of Photon into surrounding local gauges and
fields. In the middle of this graph you could see mapping into electron-positron pair (electron magnetic field looks like that of bar magnet 8 ).

This is product of fractal RTDG (n-dimensional enlargement) research, main focus of it is Calabi Yau manifold build . Photon mapping v.01 is HeSPe v.03 scene with core object sphere. EM field described on graph do match with field of 3d rotating
Photon. This is version v.01 of Photon mapping and I am going to further research.

Based on new kind fractal that I developed RTDG (Reflection Three Dimensional Graphical), there is 3d CAD scena only with one core object that reflections only one same pattern or part of it, that serves to n-dimensional enlargement.


3d CAD rendering script/ simulation for computation physics of light near perfect realism
(not presentation for scientific purpose yet !!)

DETAIL ZOOM Mapping of Photons into Electron-Positron pairs HERE !!!

http://pixels.com/featured/cold-fusion-mapping-of-photons-into-electron-positron-pairs-peter-vesely.html


reader Steve G. said...

Brilliantly said.

To add a couple of refinements, Kant's transcendental originates in Plato's great Theaetetus, and Bohr's full-blown Heracliteanism was his secret weapon against Einstein. Most strangely, neither Newton nor Einstein understood the connection.


reader Pigasus said...

One notes Don says he doesn't believe in Superstrings. I might add that I don't "believe" in Gravity in a similar sort of way of communicating the idea of the value of belief in science. There is zero "experimental evidence." He does not say there is "zero evidence." Wink wink going on.


reader Don said...

Thanks, but it wasn't me. I'm just spitting back what I read in Weyl. But thank you for the additional historical links, I will have to look into them to get more insight into what you are saying. -Don


reader Don said...

Was this directed at my comment below? Sorry, I don't follow your thinking. I was just commenting on Lubos' comment (that somehow got mangled): "But the way how the empirical input is used to decide about the fate of theories is always indirect to some extent".


reader kashyap vasavada said...

You have an interesting point. It is probably true that experimentalists are much more wedded to the so called *objective reality* than theorists. After all they work with
their hands and strongly interpret the data in terms of reality!! People forget
that every data has to pass through our consciousness for interpretation though
the inputs are sensory! Just remember arguments in connection with Bell’s
theorem and related experiments. But in the quantum world that is the way it is.
BTW in the following reply to Pigasus, I think, it was a "comedy of errors" ! Pigasus was probably commenting on Don Lincoln’s comments, not you Don!


reader kashyap vasavada said...

Sorry. The above comment was a reply to Don and not pEGO. I wish there is a way to edit comments after you press a button!


reader pEGO said...

It is OK,
but next time you plan before do, because of check that time is too late for
act. Anyway present time I am preparing scientific presentation of fractal RTDG
for n-dimensional enlagrement and I am going to post soon.


reader Don said...

Hi kashyap

Thanks for the clarification! Interestingly, I am an experimentalist! Unfortunately, there is no theory to explain the data I work with and gather. It is a wild free for all where people can say almost anything they like and get away with it. Recently I have been trying to develop a theory of cell injury. But the inertia is overwhelmingly against it. I am working right now with a physicists and he is in awe at how biomedicine "works". I, on the other hand, am in awe of how organized physicists are, in spite of whatever little philosophical quips I may throw out there. Nice to hear from you, Sir! -Don