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"Reasoning in Physics"

30 Comments -

1 – 30 of 30
Blogger Matthew Rapaport said...

Excellent review as always Dr. H! Since I am a philosopher I find myself appreciating your appreciation. I am presently re-reading E.J. Lowe's "The Possibility of Metaphysics" (1998) which is specifically directed at metaphysical clarification for the sake of advancing science (in general not physics specifically) another good read for you if ever you had the time. Glad you are enjoying the conference. Hope you have a nice holiday season

8:43 AM, December 21, 2016

Blogger Sabine Hossenfelder said...

Matthew,

I'm presently reading a book on metaphysics, and while it's not bad I don't find it particularly useful either. So, thanks for the reading recommendation.

9:28 AM, December 21, 2016

Blogger Uncle Al said...

time-symmetry in quantum mechanics implies retro-causality Pure reason absent empirical postulates fails. Euclid’s Fifth Postulate is incomplete re maps, Shroud of Turin. Newton bobbled c, h, and k_b. The Equivalence Principle prohibits baryogenesis.

Breaking time reversal symmetry creates chirality. arXiv:1006.0762, doi:10.1103/PhysRevA.82.043811. Chirality is the strong arrow of time. The Second Law is statistical. doi:10.1038/nature08680; arXiv:hep-ph/0501282, doi:10.1103/PhysRevD.71.057501; arXiv:condmat/0307056, doi:10.1103/PhysRevLett.91.247404; doi:10.1016/0009-2614(90)87240-R

Matter in excess of antimatter prohibits retro-causality. SUSY and M-theory are not empirical at exact spatial mirror symmetries. Dark matter is Milgrom acceleration, Noetherean leakage of angular momentum via trace spatial chiral anisotropy.

10:54 AM, December 21, 2016

Blogger TheBigHenry said...

"Should “constern” be a verb? Discuss."

I don't think so since the word "consternate" already exists for the implied meaning of "constern".

11:45 AM, December 21, 2016

Blogger Mathias Frisch said...

Thanks Sabine! But you did bestow two extra 't's on me!
Best, Mathias Frisch :)

1:23 PM, December 21, 2016

Blogger Rick Roesler said...

"Constern" is a great word! Particularly because it sounds so much like "concern" but with more depth of concern-edness. It's like my old boss who used to say he was "flustrated" = "flustered" + "frustrated"

6:01 PM, December 21, 2016

Blogger Arun said...

Just as the Standard Model may not be a UV-completion of strong, weak & EM, a theory of quantum gravity might go beyond an effective quantum theory of gravity based on general relativity, but not be UV-complete.

10:37 PM, December 21, 2016

Blogger Sabine Hossenfelder said...

Mathias, Sorry about that, I took back a few 't' :o)

1:27 AM, December 22, 2016

Blogger Sabine Hossenfelder said...

Arun,

Yes, it might. What I'm saying is that if you want to develop a theory on purely mathematical grounds (well, we all know there's no data, right?) then you need a very convincing mathematical criterion for guidance, and UV-completion is exactly this. The thought being that the lack of UV-completion is how we *know* (can't emphasize this enough) the current theories are incomplete.

Now if you say I don't care about UV-completion, you can do all kinds of things, fine. But what's your reason to believe it has anything to do with nature? If you do that to construct a testable phenomenological model, fine - these models have a different purpose, they're there to guide theory development all by themselves. But if you allow people to construct theories that neither solve a problem nor are testable, where'd this get us? (That's basically what happened with inflation, and there you can see where it got us.) Best,

B.

1:32 AM, December 22, 2016

Blogger B said...

That's basically what happened with inflation.....

Care to elaborate what you mean by that?

5:13 AM, December 22, 2016

Blogger Sabine Hossenfelder said...

B,

Inflation was invented to solve several finetuning problems. It's debatable whether these are problems that needed solving to begin with - they're clearly not on a mathematical level as rigorous as self-consistency. Either way, inflation doesn't actually solve these problems. But now it's become a business, so people are producing more and more models. There are infinitely many field configurations and potentials that one can think up, and therefore I don't see any end to this model production. Hence I think it's a good example what happens if you take away a quality criterion (in this case, limiting finetuning). It gives people a free pass to do anything, basically (provided you play by the rules of the field). The outcome is a lot of publications with very little lasting scientific value. Best,

B.

6:35 AM, December 22, 2016

Blogger David Thornton said...

Bee, interesting blog. I really enjoy your quirky, slightly 'sarky', and insightful sense of humour - especially in this case as neatly embodied in the fourth paragraph outlining workshop themes. BTW, do you ever respond to Uncle Al's posts?

1:19 PM, December 22, 2016

Blogger Bob said...

I am not a science professional, but I have a question that has worried me for a while: Do those of you who rely on mathematics as a proof believe that math is an analogy? That is, that math is an analogous, or symbolic, system that describes reality (like language, maybe)rather than a reality itself?

3:56 PM, December 22, 2016

Blogger Matthew Rapaport said...

I am not a physicist or mathematician but I do believe you are correct. Math follows reality, it doesn't determine it.

9:17 AM, December 23, 2016

Blogger Uncle Al said...

...1) Organic chemists respect chiral consequences. Perhaps Bee is amused by my heresies’ trivial testability.
...2) Theoretical physics is rigorous, aesthetic, then tuned to observation. String/M-theory quashed falsifiability.
...3) Experimental physics as business model observes within theory. 1928 Cox recanted parity violation. 1956 Yang and Lee had Madame Wu.
...4) Green’s function removes geometric chirality. Mirror asymmetry has ugly matrices and prolix equations. Empirical error is merely ~10^(-10), prohibiting baryogenesis and requiring dark matter, spraying theory with tiny holes.

Physics, “Idiot! Now we are both in the hole.”
Chemistry, “I live in this hole. I know a way out.”

Stalemate.

11:00 AM, December 23, 2016

Blogger Sabine Hossenfelder said...

David,

Thanks. I rarely respond to Uncle Al's posts. He rarely seems to actually want a reply.

11:21 AM, December 23, 2016

OpenID darwinwins said...

Hello Dr. Hossenfelder

I enjoyed this article. Thank you for your highly informative posts throughout the year. I learn a lot from them.

Happy holidays.

Neil Bruce

12:37 PM, December 23, 2016

Blogger David Thornton said...

Bee, Indeed! Since I started reading your blogs a little while back, Uncle Al's posts have usually been statements and not questions! They are very Alice-in-Wonderland-ish, and seem to stem from a supremely hard-core physicist/chemist. They invariably leave me with an underlying sense of questioning that make me think that I really don't know much - or that he is poetically simply 'pulling my leg'! Anyway, I'm looking forward to all your future blogs - they brighten and enlighten my day - I'm glad that I stumbled onto your interesting blog site! Happy Holidays!

1:09 PM, December 23, 2016

Blogger Rob van Son (Not a physicist, just an amateur) said...

Uncle Al's writings always remind me of the postmodern text generator and it's descendants:

SCIgen - An Automatic CS Paper Generator
https://pdos.csail.mit.edu/archive/scigen/

http://dh.elsewhere.org/pomo/

1:18 PM, December 23, 2016

Blogger Uncle Al said...

An alpha-quartz single crystal is self-similar down to one 0.113 nm³ unit cell, enantiomorphic space groups P3(1)21 right-handed or P3(2)21 left-handed. Every atom is in a 3-fold helix, 3(1) or 3(2). A geometric Eötvös experiment loads four 5-gram P3(1)21 test masses against four 5-gram P3(2)21 test masses, 6.68×10^22 pairs of 0.113 nm³ opposite shoes. All measurable observables exactly cancel, geometry perfectly diverges (anonymous unit-mass point distribution in space. doi:10.1107/S0108767303004161, Section 3ff).

...1) The Equivalence Principle fails. Baryogenesis happened. Exact space-time mirror symmetry is flawed. No postulate can resist empirical falsification.
...2) The Equivalence Principle holds. Baryogenesis is forbidden. Space-time is exactly mirror-symmetric.

https://bruceravel.github.io/demeter/artug/atoms/space.html
...Middle of page, "enantiomorphous pairs"
http://mazepath.com/uncleal/flack.pdf
...Exhaustive crystallographic handedness. P3(1,2)21 and P3(1,2) are maxima.

11:36 AM, December 24, 2016

Blogger Sabine Hossenfelder said...

piein,

I didn't approve several of your comments, not because of the "babe" but because they don't contain any relevant information. I don't care at all what you think I should "admit to myself" or what "But have fun with yourself being wined and dined by the hungry wolves" is supposed to mean, but nobody here will have any benefit from your rambles. Neither, for that matter, do I care whether you think your comments were "reasonable". If I don't think a comment is useful for my readers, I'll not post it. Best,

B.

12:54 AM, December 25, 2016

Blogger Pfogle said...

Dear B, thank you for the considerable time and effort you put into these posts, which are my main line into a critical (but reasonable!) view of, particularly, physics and gravity. They are my favorite read on the internet.

I can see how a combination of advances using analogue systems, and the work on theory space, could bring fresh ideas and new insights on their validity, but I'm not clear on how these relate to the 'real world'. At some point there has to be predictions that intersect our energy regime, and are accessible to experiment.

3:56 AM, December 25, 2016

Blogger Vedran said...

Recent particle physics experiments may be telling us there's no SUSY, GUTs, etc.
(May or may not, for the sake of the argument let's say they do.)

If all these ideas are wrong may these experimental results be telling us that the initial hypotheses that led to them were wrong too?
(extension of gauge group, unification/enlargement of gauge groups, hierarchy, naturalness,...)

If that is the case (and again, it may or may not be), how far back should we look to find a nice solid ground again? Experimentally it is clear which "truths" hold and which do not. But how about the theory? Which theoretical "truths" can we be truly certain about?

Cheers,
V

2:13 PM, December 25, 2016

Blogger piein skee said...

wow, took the easy target sentence out of the middle of its context and heaped ridicule on it for lacking content, and finished with a glob of self-glorifying insincerity about the good of your readers. Consider me humiliated. On your side you'd have to literally murder someone or sell crack or something like that to get any lower. I don't personally give a shit, but just to say you will eventually make enemies with one sided humiliations based on a deceit facilitated by a misuse of position. This blog constitutes a tiny little chunk sized baby mushed exposure to power, and yet you fail to resist the temptation to misuse it for personal convenience. That's a catastrophic failure of character. I challenge you to post my whole original statement, and criticize all of it, and allow me to defend. Because from reading this blog I am confident that your knowledge is patchy. Did you switch from mathematics to physics because you were failing or giving up? I think the answer to that is yes.

6:47 PM, December 25, 2016

Blogger Sabine Hossenfelder said...

piein,

I am posting your comment so that everybody can see the quality of your comments, and will then move on to put you on the blocked list. Good bye,

B.

12:50 AM, December 26, 2016

Blogger Sabine Hossenfelder said...

Vedran,

Well, yes, we should reconsider these hypotheses. But it isn't happening. Best,

B.

12:51 AM, December 26, 2016

Blogger Sabine Hossenfelder said...

Pfogle,

Yes, eventually you want to arrive at testable predictions, that's the point. If you use one quantum system to 'compute' what another one does, you can then go and test how well it did. Or, somewhat closer to home for me, you want to test how far an analogy between gravity and (certain types of fluids) holds. Best,

B.

12:55 AM, December 26, 2016

Blogger Louis Tagliaferro said...

Sabine said, "I’m frustrated by the lack of self-reflection among theoretical physicists"

It's good to see a researcher say that for the same reason as you've said in other articles; more honest self-reflection would likely hasten the science progress. I believe we may both share a frustration that advancements are unnecessarily slowed by human behaviors that creep into scientific methodology, even though the "behavior creep" is most often unintentional.

1:19 PM, December 27, 2016

Blogger rene anand said...

Hello Sabine

Like your comment "This consterns me because, as I explained a decade ago, it’s an unsound abuse of probability calculus. You can’t randomly distribute events that are causally related. It’s mathematical nonsense, end of story"!

I have the same problem with the use of statistical mechanics in market analysis (human behavior is yoked) but the probability theory makes the assumption the particles are not yoked in anyway; and in biomedical applications where the degrees of freedom (genetic diversity and especially during brain development) are not only unknown but highly variable in the statistical methods used often. I suspect much of the popular statistical outcomes publicized in medicine of A causes B or A is not the cause of B garnered from large scale population studies is flawed. Genomic sciences like the human 1000 genome project reveals huge diversity. Worry, we need more incisive thinking rather than relying on mindless probability calculus machine algorithms in the future. Love to hear your thoughts on this.

8:42 AM, January 18, 2017

Blogger Sabine Hossenfelder said...

rene,

It's not a topic I know much about, sorry.

11:33 AM, January 18, 2017

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