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"No, physicists have no fear of math. But they should have more respect."

21 Comments -

1 – 21 of 21
Blogger Scons Dut said...

Well ... philosophy is not a conceptual mud ...

7:51 AM, December 08, 2016

Blogger driod33 said...

Yes you should never make assumptions! I think some physicists might be afraid of what the maths suggests (like the many world's theory)and reject it due to personal reasons.

8:11 AM, December 08, 2016

Blogger Matthew Rapaport said...

Lack of "fine tuning" is an assumption yes. Naturalness seems more of an aesthetic judgement to me unless by this you mean 'naturalism' as in "all explanations must be physical". Lastly, philosophers too should make their assumptions explicit..

8:51 AM, December 08, 2016

Blogger Sabine Hossenfelder said...

Matthew,

I explained here what physicists mean by "naturalness".

9:33 AM, December 08, 2016

Blogger Sabine Hossenfelder said...

driod33,

Every theory needs assumptions. The problem isn't the existence of assumptions, the problem is the lack of clarity about what exactly is assumed and what follows from what.

9:34 AM, December 08, 2016

Blogger Uncle Al said...

an entirely self-consistent construction and yet not have anything to do with reality Sakharov conditions, matter in excess of antimatter, demand parity violation. Opposite shoes embed within mirror-asymmetric space (mount a left foot) with different energies. They vacuum free fall along divergent minimum action trajectories. Atom-scale emergent (unit cell) opposite shoes are visually and chemically identical, single crystal test masses in enantiomorphic space groups (doi:10.1107/S0108767303004161), P3(1)21 versus P3(2)21 or P3(1) versus P3(2). we need more math We need orthogonal observation. Measurably violate the Equivalence Principle.

http://thewinnower.s3.amazonaws.com/papers/95/v1/sources/image004.png
In lack of experimental guidance test space-time geometry with geometry. Look outside physics with chemistry.

10:44 AM, December 08, 2016

Blogger driod33 said...

Sorry,never jump to conclusions due to personal thoughts like that's impossible.

11:35 AM, December 08, 2016

Blogger Sabine Hossenfelder said...

driod33,

It's logically impossible, there's no jump in that argument. A theory without assumptions isn't a theory of anything.

1:06 PM, December 08, 2016

Blogger Unknown said...

I can read a paragraph of English almost at a glance. I can understand a graph or a diagram with ease. But I find that to understand an equation, I have to copy it down on a piece of paper, so it has gone through my brain. My guess is that there are people who can absorb equations like I can absorb written English. Are there any studies of this? (When I was at last in Greece I looked forward to reading signs, since as a scientist I am thoroughly familiar with the Greek alphabet. But I was shocked to find that I almost had to sound out every single word on a billboard. That tells me a lot about my ability to read English so fast.)

7:00 PM, December 08, 2016

Blogger Uncle Al said...

An ammonia molecular beam splits in an inhomogeneous electric field. Multipole selection of the population inversion into an ammonia maser is non-classically eerie. So what? Observation that only respects respected theory will be weak toward improvement and sterile toward discovery.

8:03 PM, December 08, 2016

Blogger Bill said...

Thank you for another interesting post, Dr. B. Just an observation -- I much prefer "physics math" to "math math," whose odd symbols and ever-present unintelligible proofs represent a completely different language to me. I was trained in both physics and engineering, and I can assure you that whatever fear physicists might have of math, it's far worse for engineers. Maybe it's my engineering brain that prevents me from truly comprehending the math of string theory and supersymmetry, but it's heartening to know that many physicists also have a hard time with these subjects.

1:44 PM, December 09, 2016

Blogger DocG said...

Bea, this is totally off topic -- but as far as I can tell, you've never posted on what for many is THE number one scientific issue of our time, the question of anthropogenic climate change. I may have missed a post or two, so if I'm wrong, I'd appreciate it if you would correct me, and post the link. If I'm right, however, then it seems logical to conclude that you must be a skeptic on this issue, because just about every scientist in the "warmist" camp seems to be hammering away at the dangers of "climate change" and what we need to do about it NOW. And nowadays I'd imagine any scientist whose research is dependent on funding from any establishment source would be reluctant to risk being labeled a "denier" in the poisonous atmosphere in which we now live.

I've engaged online with climate scientists, expressing doubts based on my own assessments of the data, and the responses I'm getting strike me as not only unsatisfactory from a scientific point of view, but also remarkably juvenile, filled with crude insults and ad hominem arguments.

I've followed this blog for some time and I've always been impressed, both with your expertise and your ability to explain sometimes difficult topics clearly. And I've never known you to respond in an insulting manner to any comment, no matter how naive. I'm willing to admit that my take on all this could be wrong, but I have yet to receive a satisfactory answer as to why.

I'm hoping, therefore, that you'd be willing to post your thoughts on this topic sometime soon, as I trust your ability and your judgement and would be more likely to accept your viewpoint than that of the obnoxious so-called "scientists" currently attempting to control everyone else's thinking by crudely dismissing anything that challenges their dogma.

I am currently a skeptic, but if anyone can change my mind it is you -- so I'm hoping you'll be willing to share your thoughts.

12:07 AM, December 10, 2016

Blogger Sabine Hossenfelder said...

DocG,

Yes, it's clearly off-topic, but I think I should answer this question. I have never written about climate change and I very rarely touch political questions. The reason is that on most matters I don't think I have anything to say that hasn't been said a million times by other people already.

I also seem to be the theorist all through, meaning I care more about how humanity handles the questions (badly) than about the questions themselves. I know more about political theory and sociology and economics and the way we make decisions than I know about the particular issues that need to be decided today.

Having said that, I think the evidence that the climate is changing is overwhelming. The question is just what, if anything, should we do about it. That partly depends on what you believe is causing this and that seems to be what most of the discussion circles about. Unfortunately, what gets drowned in this discussion is that we'll have to deal with it regardless of what's causing it and the longer we postpone coming up with action plans for this, the more economically costly it will get.

Now here's the rub: I often write about what's going wrong in the scientific communities that I'm part of. In a nutshell, nobody's taking any measures to prevent social and cognitive biases in theory development. But these are systemic problems and are almost certainly present also in other disciplines. The consequence is, sad but true, that I am having more and more difficulties to trust scientists generally.

Hence, for me the top one concern isn't climate change. Or immigration. Or Trump. The top one concern is to make sure we can trust science to work correctly.

Having said that, I'll not start writing about climate change because it would eat up a lot of my time and I don't think anyone would benefit from it. I also have to say that since I'm very future oriented, climate change isn't among my top worries. It seems exceedingly unlike it'll eradicate mankind. We'll survive this somehow and adapt.

We might however face some centuries of regress. And we will all be losers: There won't be some nations who will come out ahead and others behind - we'll all go down together. You don't need a degree in economics to see that if many people have to spend time fixing problems caused by climate change they have less time to do other things. So that's why we have to talk about this.

But what worries me much more is that I'm not sure our present systems are resilient to phases of downturn. Meaning, we might run into a feedback circle in which even a short phase of regress leads to much more regress. The reason is that in some areas of our lives we only cope because we're constantly working full power. Take antibiotic resistance. Can we afford to slow down on that front even a little bit? Take our whole information-culture. If access becomes even a little more difficult (ie costly) it'll cut off lots of people quickly, leading to more downturn, which will cut off more people, etc.

In summary, for me it all starts with the scientific system itself. We'll have to fix our own problems first. In a nutshell, that's what my upcoming book is about. (I'm done writing. I'm now waiting for my editor to get back to me.) Best,

B.

1:34 AM, December 10, 2016

Blogger Giotis said...

Well, you don't have to put everyone in the same sack, there are good theorists who are not afraid of math indeed and there are many bad ones who are.

Besides that math and physics are two different worlds in terms of formalism and terminology, physicists often loosely talk about physical concepts without even knowing their mathematical counterparts and the surrounding mathematical formalism and terminology.

I believe that right now only a handful of String theorists (Witten, Vafa and Moore are prime examples ) can follow mathematical formalism and read in productive way a mathematical paper; they are first rate physicists and Mathematicians effectively combining the two worlds.

There are also great theorists with brilliant intuition in Physics but weak in backing up their ideas with Mathematical consistency, Susskind is an example I can think of on the top of my head.

On the other hand there are (primary Mathematical) physicists lost in the Mathematical formalism who simply can't see the Physical picture or essence behind it i.e. what is physical important beneath this formalism.

So things are not black and white as you present them.

3:05 AM, December 10, 2016

Blogger S.E. Grimm said...

@Sabine,

I know, a blog is not a paper, but I miss an aspect about mathematics (in relation to physics). Nearly all the mathematical tools are designed to simplify reality. That’s why mathematics is extremely successful when applied to phenomenological physics (the relations between phenomena). However, if we want to describe the foundations of physics – reality at the most fundamental level – nearly all the mathematical tools are useless.

So I am a bit curious about your contribution to the new FQXi.org contest: “How can mindless mathematical laws give rise to aims and intention?”

5:41 AM, December 10, 2016

Blogger Sabine Hossenfelder said...

SE Grimm,

Not all mathematical tools are designed to simplify reality. Some of them weren't designed for anything in particular, they were just found to be useful. And it's more about describing reality, though in practice that often implies simplification.

I don't think I'll contribute to that essay, I don't find the question very interesting. Best,

B.

6:22 AM, December 10, 2016

Blogger Tom Andersen said...

Respect: I find it useful to look at the existing equations of physics - say a solution of the Einstein Equation - and ask myself what are the consequences of letting the solution taking you where it wants to go, rather than limiting it with community beliefs and unproven conjecture.

12:02 PM, December 10, 2016

Blogger DocG said...

Thanks so much, Bea, for your very thoughtful and reasonable response to my query re climate change. I understand your reluctance to go into detail on this topic, but I have a question regarding an essentially technical issue that comes up when I attempt to analyze certain types of data. As you know, there are various graphs now available that track global temperatures during various time periods, and when I study these graphs it seems that, as far as I can tell, there is no long term correlation between CO2 emission levels and temperature.

While CO2 levels have been steadily rising, according to virtually all the graphic displays, temperatures have been both rising AND falling AND remaining more or less level since roughly 1910, with no clear overall trend (though it is now warmer than it was 100 years ago). When I raise this issue on certain climate science blogs, I am very rudely dismissed as someone with no understanding of statistics. I am informed that if I understood how statistics worked I would realize that "eyeballing" the data means little, and the only "scientific" approach to understanding is via some sort of statistical analysis based on methods too complex for a non-scientist to understand. My response has always been that if there is a discrepancy between the data itself and some statistical analysis of that data, then something must be wrong. At that point my posts are greeted with howls of derision.

What do you think, Bea? When a graphic representation of the data itself is simple and straightforward enough to evaluate by eye, is it possible for a statistical analysis to reveal some truth hidden beneath the surface that only a mathematician can understand?

4:09 PM, December 10, 2016

Blogger Sabine Hossenfelder said...

DocG,

I am afraid I have to tell you that it is entirely correct what you have been told. Data can contain correlations that don't reveal themselves to the eyes and only a statistical analysis will pin them down.

Incidentally, my previous post discussed exactly such a case. You can study the data by eye and it will look like no correlation (look at the paper by the physicists). But do an appropriate (standard) analysis and you find a statistically significant trend. Incidentally, anybody who has done statistical data analysis can tell you that this happens frequenty. The opposite is also true: you might look at a data set and believe it has a correlation and yet the analysis will show it hasn't.

You ask "When a graphic representation of the data itself is simple and straightforward enough to evaluate by eye, is it possible for a statistical analysis to reveal some truth hidden beneath the surface that only a mathematician can understand?"

Well, you don't need to be a mathematician to understand that the human eye isn't a device to perform quantitative statistical analysis. Also, statistical analysis isn't all that complicated and it's much more used by scientists of various disciplines than by mathematicians themselves. Having said that however, graphic representation don't always reveal correlations to the eye.

I will not approve further comments on this. As I told you above I don't discuss these topics on my blog because they tend to become huge time sinks and I'm already running behind on to many things. I hope you understand.

Best,

B.


1:00 AM, December 11, 2016

Blogger DocG said...

Thanks so much for your response to my correlation question, Bea. What you've written is helpful. I'd love to get more specific on this issue, however, because I'm really curious regarding your thoughts on the manner in which statistical analyses can be used to produce artifacts driven by confirmation bias as well as legitimate correlations. But I do understand your situation and won't pursue this issue here. In my experience this sort of controversy never reaches a satisfactory conclusion in any case, and it can be a huge eater of time and energy.

6:18 AM, December 11, 2016

Blogger Vladimir Kalitvianski said...

When you write:

In lack of experimental guidance, what we need in the foundations of physics is conceptual clarity. We need rigorous math, not claims to experience, intuition, and aesthetic appeal. Don’t be afraid, but we need more math.

I could not agree with you more. But here I second P. Dirac who was pointing out conceptual problems within the existing physical theories and insisted on searching for better Hamiltonians in order to have sensible math applied. Yes, I am speaking of renormalizations and soft diagram summation. Here we have conceptual physical problems, the simplest of which is the self-induction of the electron. Math is right when it yields an infinite self-induction effect (self-mass or self-energy). It is we who impose a wrong physical construction.

4:48 AM, December 16, 2016

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