
Physicists Uncover Geometric ‘Theory Space’ - srameshc
https://www.quantamagazine.org/using-the-bootstrap-physicists-uncover-geometry-of-theory-space-20170223
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eigenschwarz
I work directly in this field. This article covers a lot of a material that is
at the forefront of theoretical high energy physics where we are neck-deep in
the 'fog of war.' Truthfully, I can think of few subjects more difficult to
describe to people not in the field than the conformal bootstrap; there are a
lot of technical details that are easy to get hung up on but are crucial for
understanding the big picture.

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slewis
Can you recommend some reading material, maybe a textbook, for folks who want
to get into the details?

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eigenschwarz
Jared Kaplan, one of the researchers mentioned in the article, has a good set
of notes here: [http://sites.krieger.jhu.edu/jared-
kaplan/files/2016/05/AdSC...](http://sites.krieger.jhu.edu/jared-
kaplan/files/2016/05/AdSCFTCourseNotesCurrentPublic.pdf)

David Tong does a good job explaining background physics and his notes can be
found here:
[http://www.damtp.cam.ac.uk/user/tong/teaching.html](http://www.damtp.cam.ac.uk/user/tong/teaching.html)

The fourth chapter of his string theory notes are about as approachable an
introduction to conformal field theory that there is. His QFT notes are good
too.

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Cacti
I really enjoy this magazine, but them and a couple others seem to have an
"earth shattering" theory announcement nearly every week and it is often hard
to tell from the articles if these are truly fundamental discoveries or I'm
just being taken for clickbait.

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amelius
I don't understand the point of most of these pop-sci articles. They are too
difficult to understand for the layman, but they are too handwavy and contain
too many silly analogies and too little insight for those who are truly
interested.

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jakubp
Then it means they are for the layman. Layman isn't after understanding, but
curiosity, wonder, anger, whatever fuels his emotional needs at the moment.

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totalZero
Are you talking about cave people, or fellow human beings?

Curiosity and wonder are the motivation for understanding, even among
researchers.

Or do you believe that researchers do their work for a PhD and for the
compensation?

Not sure why you mention anger. I picture an angry plumber ripping up an issue
of Popular Science while sitting in a La-Z-Boy and drinking a Rolling Rock.

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pharrington
The cave man was _exactly_ as human as you.

Nowhere does his post condemn the satisfying of emotional needs. In fact,
given that emotions are primary action catalysts, his post asserts Quanta is
doing very important cultural work.

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totalZero
This is such a bizarre way to totally miss the point.

Let me respond to the left turn you just took. There are genetic and social
differences between our prehistoric ancestors and modern humans. Where exactly
we draw the line of who is a "caveman" and who is not, is ancillary to the
point:

You're evaluating the statement, a "then" statement, without considering the
antecedents from its parent comment.

He uses "laypeople" to describe a group of people who are not truly
interested, who are not seeking understanding, and who use pop-sci literature
to abate basal emotions like anger.

> In fact, given that emotions are primary action catalysts, his post asserts
> Quanta is doing very important cultural work.

By that logic, every magazine for people who are not truly interested and
don't seek understanding is potentially culturally important if it can connect
with emotions. I don't buy it.

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pharrington
Cave people is such a nebulous term that I probably shouldn't have responded
to that part of your post :\

He says the layperson isn't seeking understanding, yes. To conflate that, and
curiosity, wonder, and anger, with being -not truly interested-, baffles me.
Maybe you disagree that interest manifests in ways besides seeking
understanding?

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jakubp
Thanks for clarification, it was precisely my point: layman won't understand
true detail but they won't care, because the sense of interest in those
articles comes from other 'rewards' (more emotional).

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kraig911
Reading this made me realize how I sound explaining my job to my mother. The
sounds of cars rushing over my head and "What?" echoing between my ears...

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nimish
This "bootstrap" appears to not be the "bootstrap" regularly encountered in
statistics, just fyi if you were confused like me for the entirety of this
article.

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auntienomen
Correct. Both terms do, however, refer to Baron von Munchausen's levitation
technique.

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Myrmornis
What about "the bootstrap method"? That name is commonly associated with the
data resampling technique. Did the journalist make an error in saying that it
was also used for this thing in theoretical particle physics?

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jacobolus
These are all based on a saying from the early 19th century about the
foolishness of trying to do something impossible, e.g. “It is conjectured that
Mr. Murphee will now be enabled to hand himself over the Cumberland river or a
barn yard fence by the straps of his boots.” (1834)

An earlier tall tale (from the 18th century or before) is that the fictional
Baron Munchausen pulled himself out of a swamp by his own hair. Often the
bootstrap saying is claimed to come from this source, but there’s not much
proof of that, and it’s probably a misattribution.

In computing, the idea of “bootstrapping” (“booting”) dates from the 1950s,
and refers to a computer starting with some simple capabilities which can read
some data in and go through a series of steps each of which increases its
capability, until it has been fully initialized. Metaphorically, the computer
is pulling itself up by its own bootstraps rather than getting an external
boost.

There are many other later uses of this idea of “bootstrapping”, including in
statistics (from the late 1970s) and theoretical physics.

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Myrmornis
Cool, I didn't know the literature references. However what I was asking was
whether the specific phrase "the bootstrap method" was used for this thing in
theoretical physics. I only know the statistical concept, which _is_ called
"the bootstrap method"; this physics thing sounds to me more like a "theory"
or "model" than a "method" and I wondered if perhaps the journalist had got
"the bootstrap method" from google hits (which are overwhelmingly dominated by
the statistical concept) and thus muddied the waters slightly. A fairly
unimportant question, to be sure.

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auntienomen
The journalist did not invent the physics use of the term 'bootstrap method'.
As the article makes clear, it came from some Berkeley physicists in the
1960s.

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quadcore
_He conjectured that each particle is composed of other particles, and those
others are held together by exchanging the first particle in a process that
conveys a force. Thus, particles’ properties are generated by self-consistent
feedback loops._

Can someone rephrase that to me?

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tbrownaw
Particles are figments of their own imaginations.

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jandrese
I was having flashbacks to the end of Final Fantasy X. So I'm the son of a
dream of myself made by a dead civilization about its own death?

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qubex
Funny, I was thinking of Turing’s Theta fixed-point combinator.

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qubex
As somebody schooled in applied mathematics, it never fails to strike me how
totally inscrutable and abstruse these pieces sound. It reads like a passage
straight out of Harry Potter.

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Ascetik
Because it's made up, just like Harry Potter.

"Theory Space" the name alone should give you red flags.

Sounds like another term for 'scientists discovered' what Aristotle already
knew 2400 years ago... the term "potentiality".

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empath75
Why should 'theory space' throw red flags?

If you have a set of 'theories' with some structure attached to it, you have a
'theory space'.

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thanatropism
Usually the structure in "space" is topological, i.e. some concept of a
"neighborhood".

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Steuard
And indeed there is a concept of "neighborhood" here: a set of parameters
characterizing the conformal field theory in question.

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kitsune_
If anyone is interested, the animation seems to be from David Ope

[http://dvdp.tumblr.com/](http://dvdp.tumblr.com/)

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tzahola
It's definitely by him. There's even a link to his site in the corner...
[https://davidope.com/](https://davidope.com/)

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viach
Reading the comments, it seems like sometimes animation or illustration just
shouldn't be too good, otherwise the message is ruined.

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HONEST_ANNIE
Secular scientifically oriented mind considers theoretical physics as a
fundamental. Alas, very few can really understand what the high priests at the
Institute for Advanced Study are actually doing.

Visualizations and animations provide the analog of religious iconography.
They convey the feeling of sublime to 'mere mortals'. Person may not be able
to understand the Latin sermon, but there are beautiful pictures on the wall
to look at.

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dwaltrip
The vast majority of theoretical physicists know that they need strong
experimental confirmation. It is disingenuous to imply that this isn't the
case.

What are you trying to get at? Vague poetic denigration may be fun to write,
but it isn't an effective way to communicate.

~~~
romwell
This was not a jab at scientists, but at people who eat up scientific factoids
without having much understanding of science thereof.

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dwaltrip
If that was the intention, there are certainly much better ways of responding
to such people, than to snidely put them down.

I'm not really sure what the expectation is either... Theoretical physics is
not exactly something you pick up in afternoon.

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jvandonsel
I just burned 10 minutes of my day staring at that animated GIF.

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bencoder
Same. It's only 16 frames.

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Bromskloss
Slightly larger:
[https://media.wired.com/photos/59266b77af95806129f4f65b/mast...](https://media.wired.com/photos/59266b77af95806129f4f65b/master/w_1200%2Cc_limit/Quantalarge.gif)

