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"A new theory SMASHes problems"

29 Comments -

1 – 29 of 29
Blogger David Schroeder said...

From the description of the theory that you have so excellently outlined, it sounds more like a mishmash of ideas glued together, rather than something that is derived from a simpler conceptual foundation from which solutions of the major problems of contemporary physics/astrophysics naturally fall out.

9:57 AM, November 16, 2016

Blogger akidbelle said...

Hi Sabine,

thanks, I laughed a lot. Once more it looks to me like the only recipe at hand is to piling-up fields and particles. Maybe nobody knows the answers, but many know how to word it, including syntax and grammar! Is that all there is in theoretical physics?

J.

10:11 AM, November 16, 2016

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

This SM*A*S*H. model has a strong "wheels inside wheels" feel.

10:25 AM, November 16, 2016

Blogger Uncle Al said...

Chirp a gravity wave (ocean not vacuum), get a tsunami[1]. Clap hands before a New World stepped pyramid, Quetzalcoatl chirps back (sonic diffraction grating)[2]. Spring winds' chirping sounds are birds.

The neutrino see-saw mechanism is Wesley Crusher brain lint. Axions are easily detected but unseen. Double beta-decay experiments are sterile. Ice Cube says "three generations of neutrinos." The "Higgs" is insufficiently massive to stabilize the universe.

SM*A*S*H sums the worst of physical theory curve fittings. The universe is what it appears to be. A geometric Eötvös experiment opposing enantiomeric alpha-quartz looks. Look.

[1] http://onlinelibrary.wiley.com/doi/10.1029/2005GL023783/full
[2] http://news.nationalgeographic.com/news/2002/12/1206_021206_TVMayanTemple.html

10:33 AM, November 16, 2016

Blogger Xerxes said...

I'm confused. All the ideas "proposed" in this paper are just Standard Model (plus axions). Right-handed fermions? SM. Inflaton is an existing field? SM. Strong-CP problem solved by axions? Not the SM but certainly a standard solution.

Is the objection that the adjustable parameters won't actually work out to solve the problems it purports to solve?

10:38 AM, November 16, 2016

Blogger N said...

How about proton decay?

11:38 AM, November 16, 2016

Blogger Sabine Hossenfelder said...

N,

Don't know what you mean. For all I can tell there are none of the troublesome operators in this model. Note that it's not a grand unification.

12:04 PM, November 16, 2016

Blogger naivetheorist said...

sabine:

"The name SM*A*S*H stands for Standard Model*Axion*Seesaw*Higgs portal inflation.". well, the model meets the first requirement for any model in theoretical physics - a clever or cute acronym.

richard

3:36 AM, November 17, 2016

Blogger Sesh Nadathur said...

Alternatively, it could be a modification of gravity. Regardless of what xkcd says.

Theories of modified gravity without any non-baryonic dark matter component fail to fit the CMB power spectrum. In fact they are guaranteed to fail to fit the CMB, unless they are also non-local - in that the gravitational force somehow points in a different direction to the location of baryonic mass. This is a well-known fact, acknowledged even by prominent MOND proponents like McGaugh.

Every attempt to get modified gravity theories to fit the CMB had either failed, or has introduced another form of dark matter anyway (and generally still failed).

So in fact XKCD was literally correct: the idea that there is no dark matter and it is all a modification of gravity simply does not fit the data on the largest scales.

4:24 AM, November 17, 2016

Blogger Sesh Nadathur said...

(Note that I am not claiming the CMB proves dark matter must be CDM, or that it must be WIMPS, or anything other than that it must be dark - not coupled to photons - and it must exist, even in theories of modified GR.)

4:26 AM, November 17, 2016

Blogger Maro said...

How many (new) parameters does this model have?

6:33 AM, November 17, 2016

Blogger Sabine Hossenfelder said...

Maro,

I don't know, it doesn't say so explicitly in the paper. Please see the second to last paragraph for my counting of what the model adds. It brings me to at least 12 new parameters, but I'm not sure that's a complete count. The reason is that the paper doesn't explain much about the Higgs portal thing and it's not a topic I know very much about. Best,

B.

6:36 AM, November 17, 2016

Blogger Maro said...

Sabine, do you know if it's possible to make new predictions / experiments that can be used to verify/disprove this model? I'm asking because you write "... if I think this model might be correct. The answer is almost certainly no.", which implies to me you think this is the sort of model that _does_ make testable predictions, so it's (fortunately) possible to talk about correct / not correct.

Another angle is, I presume it's possible to pick those >10 params in a way to fit existing observations?

8:18 AM, November 17, 2016

Blogger Sabine Hossenfelder said...

Maro,

It's a phenomenological model. The whole point of making phenomenological models is that you can test them. So, yes, you can test that, in principle. Look for the axion, look for the signatures of Higgs inflation, and so on. Look at the paper??

Even if you'd find anything though, I suspect it would be very hard to find out it's this specific model. You'd need a tremendous amount of data for all kinds of things. Best,

B.

8:31 AM, November 17, 2016

Blogger Uncle Al said...

http://www.mpbio.com/images/product-images/molecular-structure/05211962.png
http://www.essentialchemicalindustry.org/images/stories/610_Polymethyl/PolyM2MP_01.JPG

Phthalo Blue hugely self-associates like a deck of cards. Even a dimer changes the optical absorption spectrum. It dissolves in 338 °C boiling concentrated sulfuric acid. Dissolve it in Plexiglas.

One free sample later, the VP R&D held 500 grams of 30 wt-% Phthalo Blue single molecules in Plexiglas, a masterbatch dye. Pour components into a desk top thingie, out comes stuff. (It usually makes jet turbine high temperature nickel superalloys.)

Physical theory has an empirically incomplete postulate. When derivation fails, look elsewhere.

10:23 AM, November 17, 2016

Blogger Bill said...

Thanks for the post and comments, Sabine.

It seems that particle physicists today are relying more and more on theories with clever pop culture titles (MADMAX, ORPHEUS, [Hulk] SMASH) based on hypothetical unseen or undetectable particles and fields. If a theory can never be tested (especially one based on Planck-level energies or ad hoc piled-on parameters), then it's no different from a religious belief. As you are wont to say, "it's an old idea," but it seems to be very much in vogue nowadays. Perhaps the idea is that if you can get enough people to believe in it (string theory, inflation), then it becomes true. (And I say that as an disillusioned American watching his country adopt lies as the truth).

10:33 AM, November 17, 2016

Blogger piein skee said...

No, because he's transformed x stand-alone ideas, each requiring effectivrly arbitrary parameter setting decisions. into a partially self-referential equation. As such the individual speculations, which would have to be summed, are exchanged for one level of speculation applicable to the system as a wh9ole. That hugely enhances the potential of the solution, compared with the sum of those same solutions run in isolation. Lots of mutually independent ways to demonstrate the enhancement e.g. Occam.

8:43 PM, November 17, 2016

Blogger piein skee said...

hi I'm just reposting the above comment because the excerpt from your post dropped out somehow. It's not really readable without the excerpt because the context for certain words is taken from there (e.g. 'speculation')

Doc Hossenfelder's concluding prognosis was "But when you combine several speculative ideas without observational evidence, you don’t get a model that is less speculative and has more evidence speaking for it. "

No, because he's transformed x stand-alone ideas, each requiring effectivrly arbitrary parameter setting decisions. into a partially self-referential equation. As such the individual speculations, which would have to be summed, are exchanged for one level of speculation applicable to the system as a wh9ole. That hugely enhances the potential of the solution, compared with the sum of those same solutions run in isolation. Lots of mutually independent ways to demonstrate the enhancement e.g. Occam.

10:25 AM, November 18, 2016

Blogger Sabine Hossenfelder said...

piein,

I think you misunderstand my point. I think you are saying that by throwing n ideas together you don't necessarily get Sum_n parameters. Fine. Though in this case for all I can tell you still indeed have all the parameters, you just remove some problems that previously were entirely fatal. What I said however was merely that the probability that a conjunction of two untested hypothesis is correct is always smaller than each of them separately, even if less than Sum_n. It goes under the name conjunction fallacy. Best,

B.

11:18 AM, November 18, 2016

Blogger piein skee said...

Sure that's right for the situation he strings together several independent ideas into a sequence where the subsequent depends the preceding being correct, because in that scenario the probabilities multiply. And that is what he's doing on one side hence it seems a very plausible first-approximation

But what he's actually doing is marrying from two different conceptually opposite directions, one being from problems, the other being from solutions. And that changes the equation in this particular sense relating to robustness

12:05 PM, November 18, 2016

Blogger Sabine Hossenfelder said...

piein,

And what makes you think that your argument "changes the equation"? Exactly what about it supposedly changes it? We have here a conjunction of ideas that supposedly explain a conjunction of problems (several of which didn't need solving in the first place). How do you think this makes this multi-model any more likely to be correct than right-handed neutrinos to be correct, just to pick a random example?

Best,

B.

1:04 PM, November 18, 2016

Blogger piein skee said...

xerxes says: I'm confused. All the ideas "proposed" in this paper are just Standard Model (plus axions). Right-handed fermions? SM. Inflaton is an existing field? SM. Strong-CP problem solved by axions? Not the SM but certainly a standard solutio

That's right, though I think you're reacting to the negative signalling from commenters more than doc hossenfelder's piece. The comments are considerably are absolutely in the negative whereas her piece was actually positive.

But you are right, what is not to like about solving a bunch of problems in terms of each-other? That is not curve-fitting uncle-al! This is like simultaneous equations. It's not curve fitting.

Doesn't mean it's right. I don't actually think it's right. But the methodology is definitely right.

1:12 PM, November 18, 2016

Blogger piein skee said...

hi doc hossenfelder - I'm not making those mistakes but I'm not being very clear either. What I'll do is assemble my best eloquence (which isn't great) and try again later. The reality is that you already will know the distinction - I'd take poison on that. I've seen you say it. It's just a case of knowledge that is general in of itself, does not automatically rise to the surface in a given context. Brains just don't provide that service...if they did the world wouldn't be so messed up. But they don't. I'll be back.

2:13 PM, November 18, 2016

Blogger Uncle Al said...

@piein skee "This is like simultaneous equations. It's not curve fitting. "

A swing pendulum measures weight. It fails in vacuum free fall. Its equation omits the bob. A torsion pendulum measures mass. It works in vacuum free fall. Its equation has the bob. Given equal periods, equate the equations. Gravitation/length is then inversely proportional to inertial moment. Run the units. Really?

10:44 AM, November 19, 2016

Blogger piein skee said...

Hi Uncle-Al - you might be right, but just to say that being 'like' something leaves a large amount to the context in play. Clearly, there's no way to write equations and benefit from mathematical certainty, at that sort of stage. But it is 'like' simultaneous equations in that you are trying to solve a set of problems in terms of each other. I'm going to try to capture the benefit in a short comment but I obviously accept the main reason I'm doing that is so that people are able to explain what's wrong with it. But to that end, will you mention why you see curve-fitting?

4:02 PM, November 21, 2016

Blogger Ali Lezeik said...

I don't know why people publish papers based on speculations, this way you'll get a new speculation which is based on a speculation, and others will use this new paper to publish a newer one, so it'll be speculation based on speculation based on speculation !! Speculationception !! I mean it's interesting and all, but it makes no sense to do all that work when there is no solid infrastructure to the whole theory. And I believe it's sad to see all these minds "wasting" their time on that rather than really trying to go from A to B and come up with a bright clear conclusion. Well it might not be a complete waste of time since you could find "Something" while doing the research, but I guess my point is clear enough.

5:29 PM, November 21, 2016

Blogger Uncle Al said...

@ piein skee Science is rigor that survives empirical falsification (Galileo, Popper). The penultimate sentence of my prior post is crap. Don’t believe proclaimed authority. Look.

If the equations’ periods are equal, then time = time. LOOK at the two equations’ dimensions, run the math (torque constant). Bee knows physics (uncomfortably) has never observed whether opposite shoes diverge at the required sensitivity level, whether reality is fundamentally not mirror symmetric as postulated. Gravitation theory would violently swerve, or not. Look.

10:23 AM, November 22, 2016

Blogger Mr Roboto said...

I like the general approach of the model: bottom-up rather than top-down. We've had forty years of supersymmetric, top-down models, each usually adding dozens of new fields and hundreds of new parameters, all in the name of more symmetry. But now that it's starting to look like supersymmetry isn't going to pan out--at least not in the energy ranges accessible to the LHC--I think it's time that more effort be put into these sort of modest, conservative extensions of the Standard Model. Such a minimal extension of the SM coupled to asymptotically safe gravity may in fact be the final theory, regardless of how satisfying physicists may find it.

12:26 AM, November 23, 2016

Blogger David Schroeder said...

This paper underscores the fact that we seem to be confronting a new 'aether' conundrum. The world awaits another Einstein, whether individual woman or man, or research team, who will illuminate the darkness, and perhaps usher in a major paradigm shift in our thinking.

7:27 AM, November 23, 2016

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