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"Book Review: “Why String Theory?” by Joseph Conlon"

35 Comments -

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Blogger Buttersky20000 said...

Sandick?

9:52 AM, May 30, 2016

Blogger Sabine Hossenfelder said...

Nope - not the person I had in mind. But in case I'm wrong, I'm happy to let myself be educated, so if you have a reference please post it. The paper I am referring to is from 1985.

9:56 AM, May 30, 2016

Blogger Joel Oredsson said...

I think it is Edward Witten (together with Mark Goodman)!

9:56 AM, May 30, 2016

Blogger Phillip Helbig said...

Ed Witten.

9:56 AM, May 30, 2016

Blogger Sabine Hossenfelder said...

Yes, right! It's Ed Witten :)

The book goes to Joel - Sorry Phillip, he beat you by like 10 seconds or so!

Joel, can you send a note to hossi[at]fias.uni-frankfurt.de and let me know the address you want the book be shipped to?

9:59 AM, May 30, 2016

Blogger Phillip Helbig said...

You need to increase the resolution of the timestamps. :-)

At least on some blogs, the order in which comments appear does not always reflect the order in which they were received. :-|

To boost my credibility here is the reference:

Goodman, Mark W.; Witten, Edward: "Detectability of certain dark-matter candidates", Physical Review D, Volume 31, Issue 12, pp.3059-3063, 15 June 1985

10:02 AM, May 30, 2016

Blogger Joel Oredsson said...

Woho!

Done, thanks!

10:10 AM, May 30, 2016

Blogger Daniel de França MTd2 said...

Sabine, this is the paper you are referring to: http://kicp.uchicago.edu/~collar/goodman.pdf

They calculate the cross sections for certain types of dark matter, but the proposal, according to this very paper, is due: Drukier and Stodolsky, citation number 5. Goodman and Witten show that in the 2nd paragraph of their paper.

10:19 AM, May 30, 2016

Blogger Sabine Hossenfelder said...

Daniel,

They proposed the detector - to detect neutrinos, as it says in there. Goodman and Witten pointed out it could also be used to detect dark matter (certain types thereof).

10:24 AM, May 30, 2016

Blogger Wolf Dancer said...

A good review. It is clear from his metaphors that he either never took college literature or his teachers were asleep at the job. Every good writer needs to have suffered through one or more merciless but correct lit professors who prune them of their bad metaphors and trite phrases.

Of course things change with time, in 1975 I would have gotten nailed for using the "prune" one here. But it is not so over-used today.

10:36 AM, May 30, 2016

Blogger Uncle Al said...

"string theory, supersymmetry, the multiverse and other fantasies " The maths are deep, elegant, and hugely published. No performed experiment validates. Attempt falsification. Geometry is a proper test of spacetime geometry.

A geometric Eötvös experiment sources physics' chiral quirks (e.g., baryogenesis). Physics excludes it. Chemistry embraces it. Exhaustively validated physics apparatus runs it. Observe single crystal left-handed alpha-quartz versus single crystal right-handed alpha-quartz violating the Equivalence Principle. No prior observation is contradicted. The worst it can do is succeed.

11:54 AM, May 30, 2016

Blogger Andrew Thomas said...

I've almost finished the book and I thought it was fair and objective about the current state of string theory. A nice change from the usual. Perhaps too much detail meant some of the later chapters dragged. I think your review says it all.

11:58 AM, May 30, 2016

OpenID johnduffieldblog said...

And the second prize which goes to Phillip, is two copies!

Nice review, Sabine. I share your sentiments.

12:34 PM, May 30, 2016

Blogger Sabine Hossenfelder said...

John,

The other copy is in a poor shape, not only because I ran out of sticky notes and bent over multiple corners, but I also dropped it on the ground and almost ran over it with my car. Also, I'd prefer to keep a copy myself, it might come in handy as a reference for this or that.

12:55 PM, May 30, 2016

Blogger pete said...


"He somehow forgets to mention that the AdS/CFT predictions for heavy ion collisions at the LHC turned out to be dramatically wrong, and by now very few people think that the duality is of much use in this area."

I know you've talked about the failure of AdS/CFT to correctly predict results when it comes to heavy ion collisions before, but I was wondering what exactly this might mean in relation to the prospects of string theory (which I still consider myself a fan of). Is there something in the calculations we're missing? Does the quark-gluon plasma generated by those collisions behave in a way that wouldn't actually justify using AdS/CFT? Does not being applicable "in this area [high energy particle collisions]" say anything about it's generality?

I've always wondered how serious a problem this is for the theory, especially considering the fact that several things could be going wrong outside of AdS/CFT actually being wrong in some sense. I'd really appreciate any help clearing all this up!

10:31 AM, May 31, 2016

Blogger akidbelle said...

Hi Sabine; one thing is certain, I won't by this book.

After 40+ years of quasi-stagnation, maybe SciFi is all that remains to be found...
On the other hand, I assume you do have a clearly agreed list of what needs to be solved or found. I mean agreed by the community.

Following the last 40+ years, and considering the integral sum(IQ x time) or the sum sigma(ink + paper) involved on those problems, it is somewhat natural to considering that the manner is not appropriate. String Theory is not better, OK, but at least it seems seductive and there is nice work to do...

In my opinion, the alternate possibility would be that the list is wrong. If you take that seriously, the question you may need to ask is: what kind of problem do we miss to solve in order to explain some observations which, based on your generation's theoretical background, are not problems at all?

Cheers,
J.

10:56 AM, May 31, 2016

Blogger Henning Dekant said...

"... the book is reasonably well written."

Damning with faint praise.

The wikipedia entry on that idiom should link to this review :-)

11:54 PM, May 31, 2016

Blogger Sabine Hossenfelder said...

Henning,

I actually meant it. The writing is good, it's easy to follow, it's not dull either, and the sentences are understandable. There are some authors who manage to fabricate sentences I have to read a couple of times to parse, but I had no problems with this book. The oddest thing about the writing in this book is, as I mentioned, that Conlon goes to length to explain all kinds of technical expressions (like strong and weak coupling) but then clutters the text with Latin, French, and German - why? I mean, I learned both Latin and French (and speak German), but still I had too look up some of the lesser used expressions just to figure out what he was trying to say. Did he do this to show off or to annoy the reader? It doesn't make any sense to me. Best,

B.

1:18 AM, June 01, 2016

Blogger Sabine Hossenfelder said...

pete,

No, it says that the quark gluon plasma probably isn't as strongly coupled as they originally thought it is, which makes the AdS/CFT duality even less useful as they initially thought it is (QCD not being supersymmetric). There might be some aspects for which you can use it, but you'd still have to add some perturbative calculations. And then, once it turned out that the real world is messy, most string theorists seem to have lost interest in the topic.

Don't get me wrong, I don't blame them - I come from an institute where everybody worked on heavy ion physics and wanted nothing to do with it. Instead I went to the US with the intention to become a string theorist. So I totally understand the sentiment. I also think though this was clear from the very beginning that string theory wouldn't turn out to be a magic wand to solve heavy ion physics. I am mostly annoyed that first they go around and make rather silly big claims and then when they figure it isn't that easy, instead of admitting they might have been a little too naive, simply hurry away and pretend it's never happened. Best,

B.

1:28 AM, June 01, 2016

Blogger Sabine Hossenfelder said...

akidbelle,

I think you will like my upcoming book...

1:30 AM, June 01, 2016

Blogger akidbelle said...

Hi Sabine,

you don't take much risk writing this; I like what you write already.
I am sure you will let us know when it's out...

By the way, when?

J.

3:45 AM, June 01, 2016

Blogger Sabine Hossenfelder said...

akidbelle,

My deadline is Dec 2017, and then it might take 9-12 month to publication. But the way it looks presently I might be done earlier. So... I am guessing some time between late 2017 and late 2018. I'll tell you more about this once I know the details better. Best,

B.

3:53 AM, June 01, 2016

Blogger Noa Drake said...

Indeed akidbelle, certainly on your last remark.

11:38 AM, June 01, 2016

Blogger Noa Drake said...

Curious about your book Sabine, good luck. My guess is the next 10 years will be pivotal for physics research.

11:42 AM, June 01, 2016

Blogger Shantanu said...

Sabine, I wish I was as luck as you to get free copies of all these books :-)
Anyhow does the book address/acknowledge the criticisms of string theory by Woit, Smolin,others?
If so, what does it say?
Thanks

7:13 PM, June 01, 2016

Blogger Sabine Hossenfelder said...

Shantanu,

The book has a chapter addressing criticism, but it's not explicitly aimed at any person. I don't have the book with me and can't recall exactly which point it picked up on. Not the ones that I personally find troublesome. One was the question of UV finiteness I think.

Well, they send me the books because they want me to write a review on them. You should look at it this way: I get a 30$ book for free, and in exchange I have to read 250 pages and write 1000 words. It's not a particularly great deal.

12:28 AM, June 02, 2016

Blogger Mark said...

Hi Sabine,

I would say your main criticism of the failure of holography in heavy ions is unfounded. While many in the field (myself included) remain highly skeptical of it's applicability, it nevertheless has remained a very active non-perturbative technique. For instance the bound for the ratio of shear viscosity to entropy density from holography has held up fairly well with even the most sophisticated relativistic hydrodynamic models. Also, the equation of state from holography is sometimes used in model building (normally as a comparison to a lattice EoS), and it remains one of the only ways to really compute many of the transport coefficients (which the lattice living in Euclidean space has a hard time doing). Holography has been important as a strong coupling comparison to the more canonical non-pertubative but weak coupling approaches for studies of thermalization and also anomalous transport effects. Jet quenching is obviously still a problem (I'm guessing this is where you're criticism is most heavily based on), but holography is still thriving for the time being in HICs.

7:43 PM, June 02, 2016

Blogger Sabine Hossenfelder said...

Mark,

You're putting words in my mouth I didn't use. I never spoke of a "failure of holography", I spoke of a failure of its applicability to heavy ion collisions at the LHC. And yes, I am referring to jet-quenching. I don't actually disagree with you, I just think we have a different interpretation of "thriving". Either way, to come back to my criticism, don't you think that to give a balanced account the author of the book should have mentioned that AdS/CFT doesn't just allow one to compute what's happening in a heavy ion collision? Because you could have gotten away with that impression. Best,

B.

12:16 AM, June 03, 2016

Blogger piein skee said...

"astonishing amount of so-called “science” books about string theory, supersymmetry, the multiverse and other fantasies note careful chosen placement of commata) "

Unfortunately, commas placed there do not have your desired effect. You're still saying it's all fantasy. Maybe it's different in German.

Something else: One has the distinct impression concepts like 'multiverse' you elsewhere have supported, possibly defended. Likewise String Theory.

It would add a lot clarity, if you announced major developments of your personal stance. Also it's very interesting to hear what tipped the balance.

or do I got that wrong?

3:42 PM, June 03, 2016

Blogger Sabine Hossenfelder said...

pien,

I practice the Oxford comma. And just in case the reader didn't figure that, I even explicitly drew attention to it. If I left you with the impression that I "support" the multiverse, you must have dramatically misread me. I might have said that some variants of the multiverse have some aspects that might possibly one day in the far future be useful for something. That's a far cry from being "supportive".

As I explained here, the reason we see "multiverses" popping up is that physicists don't want to realize it's logically impossible to construct a theory of nature using mathematical consistency alone. Best,

B.

2:11 AM, June 05, 2016

Blogger Uncle Al said...

Another vote for the Oxford comma:
1) I leave my estate to Tom, Dick, and Harry Each get 1/3.
2) I leave my estate to Tom, Dick and Harry. Tom gets 1/2; Dick and Harry each get 1/4.

I'd go for "number" of books rather than amount. However, "amount" could be a subtle insult to the cumulated number of pages absent their partitioning into books and authors. Basic science is a religion searching for the Answer within dogma. Grant funding is a business plan intolerant of risk. It's been done before. It terrifically failed.

The multiverse is obscene. It demands that failing to validate one string theory vacuum validates all string theory vacua. Not assigning grades in a competition validates the excellence of all competitors? No. Trying real hard is not indistinguishable from doing real well. Labor input does not create value.

10:36 AM, June 05, 2016

Blogger akidbelle said...

Hi Sabine,

I like the last sentence... a real lot! It reminded me of something I read some time ago:

In Disturbing the Universe, Freeman Dyson writes, "Dick [Feynman] fought back against my skepticism, arguing that Einstein had failed because he stopped thinking in concrete physical images (as MDT does!) and became a manipulator of equations. I had to admit that was true. The great discoveries of Einstein’s earlier years were all based on direct physical intuition. Einstein’s later unified theories failed because they were only sets of equations without physical meaning. Dick’s sum-over-histories theory was in the spirit of the young Einstein, not of the old Einstein. It was solidly rooted in physical reality."

What do you think Sabine?

J.

12:04 PM, June 05, 2016

Blogger Phillip Helbig said...

My favourite example of what can go wrong when not using the Oxford comma: "I dedicate this thesis to my parents, God and L. Ron Hubbard".

6:05 AM, June 06, 2016

Blogger piein skee said...

"I practice the Oxford comma"

First to say that, what you said when 'explicitly drawing attention' was sufficient that I'm sure everyone reading was clear you wanted your sentence to be read as 'multiverses only' as fantasy.

So there's no problem, but I am presuming you are interested to known when something isn't right at the level of language.

The Oxford Comma is a stylistic....it's not something that is declared. You have to actually put the comma in a specific position. In your sentence that would immediately before the 'and' in 'and other fantasies'.

But whether you put it there, or where you put it, the comma in that situation does not change the intuitive and grammatically correct interpretation that you regard all three as fantasies.

9:08 AM, June 06, 2016

Blogger Sabine Hossenfelder said...

piein,

You're not making sense. You understood what I meant, you even say that it was clear to everyone reading, so for what I am concerned the grammatical construction I chose did exactly what it was supposed to do. Honestly, I don't really care if you think it's correct, as long as it says what I want it to say.

9:47 AM, June 06, 2016

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