9 ms·

One other mystery not mentioned is the problem of fine tuning. The standard model requires certain parameters (like alpha, the fine structure constant) to have

One other mystery not mentioned is the problem of fine tuning. The standard model requires certain parameters (like alpha, the fine structure constant) to have their current values accurate to many orders of magnitude for the universe as we know it to exist. There are two philosophical schools of thought about that -- (a) we're in the universe we're in, so by definition it must exist and there's a selection bias there; or (b) there is an underlying detailed structure that gives the values of supposed 'fundamental' quantities their shape as an emergent property of something more beautiful – and thus they're not "free" at all. This is one of the things that SUSY was supposed to solve – but it's been experimentally found to not really exist by the LHC. A good introduction about this (in the context of the Higgs mass, where the need for fine tuning is really apparent) is here: https://www.physicsmatt.com/blog/2016/11/17/paper-explainer-precision-corrections-to-fine-tuning-in-susy https://www.physicsmatt.com/blog/2016/11/17/paper-explainer-...

Ginden 5y ago
> (a) we're in the universe we're in, so by definition it must exist and there's a selection bias there; This has basically 3 possible explanations - insane coincidence, multiverse (with many versions of constants; certain forms of mathematicism also provide such "multiverse") or "reason" (simulation admin/God).
pfortuny 5y ago
Thanks for this detailed explanation. Did not know about the fine-tuning problem.
- andrewgleave 5y ago
  You may find this an interesting read: https://www.bretthall.org/fine-structure.html https://www.bretthall.org/fine-structure.html
  - pfortuny 5y ago
    Well, thanks again!
    - rrdharan 5y ago
      Also this free book on the Anthropic Principle is great: https://www.anthropic-principle.com/q=book/table_of_contents/ https://www.anthropic-principle.com/q=book/table_of_contents...
- jessermeyer 5y ago
  It's only framed as a problem when it is assumed that the values could be other than what they are. But we have no reason to suspect that they could be different. We have no idea how unlikely the current selection is given our observation is a single observable. For all we know, it's certain. 'What really interests me is whether God had any choice in creation' - Albert Einstein
  - brink 5y ago
    > It's only framed as a problem when it is assumed that the values could be other than what they are. Well then your problem would be "What fixed those values to what they are?", which I don't think is the lesser of a problem.
    - jessermeyer 5y ago
      That's not really a problem in the sense that it doesn't align with expectations. That's a genuine unknown.
WithinReason 5y ago
The article has some more instances of pysicists naming things: "The partner of the Higgs, the higgsino." "The partner of the top quark, the stop squark."
- steerablesafe 5y ago
  Mandatory SMBC: https://www.smbc-comics.com/?id=1452#comic https://www.smbc-comics.com/?id=1452#comic
- wongarsu 5y ago
  The stop squark is one of the sfermions (the superpartner particles of their associated fermions). As such they are all sparticles. Some of the other sfermions would be the sup squark, the scharm squark, the sstrange squark, the selectron or the stau. [1] In my opinion physicists are great at naming things :D 1: https://en.wikipedia.org/wiki/Sfermion https://en.wikipedia.org/wiki/Sfermion
  - saalweachter 5y ago
    It seems kind of seems hipster. "I'll name the particles something that I can later disavow as a joke if people don't like it, so I'm not risking myself."
    - mbg721 5y ago
      I mean, you only get to use "Particle McParticleFace" once.
      - Taniwha 5y ago
        Pretty sure it's its own anti-particle
    - whatshisface 5y ago
      What alternative would you propose? Greek naming? Latin?
  - 5y ago
Mizza 5y ago
“This is rather as if you imagine a puddle waking up one morning and thinking, 'This is an interesting world I find myself in — an interesting hole I find myself in — fits me rather neatly, doesn't it? In fact it fits me staggeringly well, must have been made to have me in it!' This is such a powerful idea that as the sun rises in the sky and the air heats up and as, gradually, the puddle gets smaller and smaller, frantically hanging on to the notion that everything's going to be alright, because this world was meant to have him in it, was built to have him in it; so the moment he disappears catches him rather by surprise. I think this may be something we need to be on the watch out for.” --Douglas Adams
- crznp 5y ago
  The puddle being in a hole implies a world outside of the hole. If the puddle has no means to perceive the outside world except a careful inspection of its own bounds, isn't that an interesting mystery?
- teorema 5y ago
  See also Professor Pangloss.
AnIdiotOnTheNet 5y ago
To me the fine tuning problem is a bit like saying "circles wouldn't exist without π being exactly the value it is" and wondering why π has that value specifically and not any other value. I don't think A and B are mutually exclusive. The values seem perfectly tuned for our universe because we exist in our universe, and they are probably emergent from a more fundamental parameter, possibly something like the particular Calabi-Yau manifold topology that happens to correspond to our universe (in the case of superstring theory). If we lived in a different CY topology that was capable of supporting intelligent life then we'd wonder why that one's constants are so precisely tuned for us. But then, I'm and idiot who just watches PBS Space Time and nods his head, not a physicist.
- dogma1138 5y ago
  That’s not that great analogy for fine tuning. The quantized representative value of Pi is arbitrary based our numerical system, the relationship that derives it is fixed if the relationship would change circles indeed would not exist. Let’s move the analogy to triangles a triangle has 180 degrees but that only holds true when it’s on a flat surface if you have a curvature it can have more or less than 180 degrees. So this isn’t a fine tuning problem on its own, if you would lived in a universe where triangles have less or more than 180 degrees it would represent a universe with negative or positive curvature. The issue with fine tuning is that the curvature of the universe is directly tied to the mass/energy density and any deviation from an extremely narrow range which our universe seems to sit in out of all possible values would not just produce a universe with triangles with fewer or more degrees than 180 but would either produce a universe that would collapse on itself within a blink of an eye or expand so fast that gravity would never be strong enough to cause even the most basic structures to form. So the issue really is that to produce a universe which will form galaxies and stars and survive long enough to produce life you need a lot of parameters at a certain very specific value even the smallest of deviations would not produce a universe that would ever support life, yet alone an intelligent life. What’s even stranger iirc is that the values have to be really what they are now you can’t simply 2X all of them to maintain the proportions and get the same result. And this is really what people are looking to solve, yes the androcentric is a solution if they were anything than what they are now we wouldn’t be here to discuss why, but the issue is that out of all other possible combinations you don’t seem to find another stable state and that is the true mystery.
coremoff 5y ago
somewhat related, I think, is the enormous disparity between the strength of the strong/week/electromagnetic forces and gravity (30 or 40 orders of magnitude); possible indication that there's something missing
- tsimionescu 5y ago
  Why is this a problem? If the other three forces were perfectly equal, or in regular intervals, maybe this would have meant something, but the other three forces' strength varies by x, y, z between them. Other than human intuition, there is nothing inherently different between x = 2 and x = 10^30-40.
  - coremoff 5y ago
    I don't know that it's a problem, and I'm no expert; my understanding is that differences like that can sometimes indicate that there's something else at play
  - MarkusQ 5y ago
    > there is nothing inherently different between x = 2 and x = 10^30-40 Fermat begs to differ. :)
throwawaylinux 5y ago
Isn't the whole thing made up to fit observation though? Why is that any more arbitrary than, say, electromagnetism existing?
- TheOtherHobbes 5y ago
  It's an explanatory theory with a lot - a lot - of gaps. It has been extended with some nice predictions like the Higgs. But basically it's a Franken-patchwork of math glued together quite awkwardly. Because that is what it is. Literally. It was developed by thousands of grad students and their supervisors throwing math at the wall and keeping anything that matched observations. So there was a lot of random searching involved. What's missing is a central guiding metaphor. Relativity has one. In comparison, the Standard Model is very epicycle-ish tool for calculating Lagrangians with plenty of "Yes but" and "Except when".
  - throwawaylinux 5y ago
    I'm not sure I quite explained myself, although I do appreciate the reply. See, I also don't see how one central guiding metaphor would be any less arbitrary than none, or ten metaphors. What I am asking is why would α = 0.0072973525693 be more of a problem than electromagnetism or the speed of light being constant or e=mc^2? If the fine structure constant was exactly 1 would that make it better? Why is 1 less arbitrary or more good? I understand the beauty in simplicity, fewer concepts or ideas, smaller formulas explaining more things, 1 being "nicer" than other numbers, etc. So I understand that aspect of goodness, so it is the connection to underlying observable reality I'm asking about. Because isn't it also arbitrary to think that if we could explain things in more beautiful ways then it would be a deeper understanding or closer to the truth?
    - abrichr 5y ago
      It sounds like you're asking why parsimony is desirable in science. From https://aeon.co/essays/are-scientific-theories-really-better-when-they-are-simpler https://aeon.co/essays/are-scientific-theories-really-better...: > The upshot is that there are three parsimony paradigms that explain how the simplicity of a theory can be relevant to saying what the world is like: > Paradigm 1: sometimes simpler theories have higher probabilities. > Paradigm 2: sometimes simpler theories are better supported by the observations. > Paradigm 3: sometimes the simplicity of a model is relevant to estimating its predictive accuracy. > These three paradigms have something important in common. Whether a given problem fits into any of them depends on empirical assumptions about the problem. Those assumptions might be true of some problems, but false of others. Although parsimony is demonstrably relevant to forming judgments about what the world is like, there is in the end no unconditional and presuppositionless justification for Ockham’s Razor.

Ginden 5y ago

> (a) we're in the universe we're in, so by definition it must exist and there's a selection bias there; This has basically 3 possible explanations - insane coincidence, multiverse (with many versions of constants; certain forms of mathematicism also provide such "multiverse") or "reason" (simulation admin/God).

pfortuny 5y ago

Thanks for this detailed explanation. Did not know about the fine-tuning problem.

andrewgleave 5y ago
You may find this an interesting read: https://www.bretthall.org/fine-structure.html https://www.bretthall.org/fine-structure.html
- pfortuny 5y ago
  Well, thanks again!
  - rrdharan 5y ago
    Also this free book on the Anthropic Principle is great: https://www.anthropic-principle.com/q=book/table_of_contents/ https://www.anthropic-principle.com/q=book/table_of_contents...
jessermeyer 5y ago
It's only framed as a problem when it is assumed that the values could be other than what they are. But we have no reason to suspect that they could be different. We have no idea how unlikely the current selection is given our observation is a single observable. For all we know, it's certain. 'What really interests me is whether God had any choice in creation' - Albert Einstein
- brink 5y ago
  > It's only framed as a problem when it is assumed that the values could be other than what they are. Well then your problem would be "What fixed those values to what they are?", which I don't think is the lesser of a problem.
  - jessermeyer 5y ago
    That's not really a problem in the sense that it doesn't align with expectations. That's a genuine unknown.

WithinReason 5y ago

The article has some more instances of pysicists naming things: "The partner of the Higgs, the higgsino." "The partner of the top quark, the stop squark."

steerablesafe 5y ago
Mandatory SMBC: https://www.smbc-comics.com/?id=1452#comic https://www.smbc-comics.com/?id=1452#comic
wongarsu 5y ago
The stop squark is one of the sfermions (the superpartner particles of their associated fermions). As such they are all sparticles. Some of the other sfermions would be the sup squark, the scharm squark, the sstrange squark, the selectron or the stau. [1] In my opinion physicists are great at naming things :D 1: https://en.wikipedia.org/wiki/Sfermion https://en.wikipedia.org/wiki/Sfermion
- saalweachter 5y ago
  It seems kind of seems hipster. "I'll name the particles something that I can later disavow as a joke if people don't like it, so I'm not risking myself."
  - mbg721 5y ago
    I mean, you only get to use "Particle McParticleFace" once.
    - Taniwha 5y ago
      Pretty sure it's its own anti-particle
  - whatshisface 5y ago
    What alternative would you propose? Greek naming? Latin?
- 5y ago

Mizza 5y ago

“This is rather as if you imagine a puddle waking up one morning and thinking, 'This is an interesting world I find myself in — an interesting hole I find myself in — fits me rather neatly, doesn't it? In fact it fits me staggeringly well, must have been made to have me in it!' This is such a powerful idea that as the sun rises in the sky and the air heats up and as, gradually, the puddle gets smaller and smaller, frantically hanging on to the notion that everything's going to be alright, because this world was meant to have him in it, was built to have him in it; so the moment he disappears catches him rather by surprise. I think this may be something we need to be on the watch out for.” --Douglas Adams

crznp 5y ago
The puddle being in a hole implies a world outside of the hole. If the puddle has no means to perceive the outside world except a careful inspection of its own bounds, isn't that an interesting mystery?
teorema 5y ago
See also Professor Pangloss.

AnIdiotOnTheNet 5y ago

To me the fine tuning problem is a bit like saying "circles wouldn't exist without π being exactly the value it is" and wondering why π has that value specifically and not any other value. I don't think A and B are mutually exclusive. The values seem perfectly tuned for our universe because we exist in our universe, and they are probably emergent from a more fundamental parameter, possibly something like the particular Calabi-Yau manifold topology that happens to correspond to our universe (in the case of superstring theory). If we lived in a different CY topology that was capable of supporting intelligent life then we'd wonder why that one's constants are so precisely tuned for us. But then, I'm and idiot who just watches PBS Space Time and nods his head, not a physicist.

dogma1138 5y ago
That’s not that great analogy for fine tuning. The quantized representative value of Pi is arbitrary based our numerical system, the relationship that derives it is fixed if the relationship would change circles indeed would not exist. Let’s move the analogy to triangles a triangle has 180 degrees but that only holds true when it’s on a flat surface if you have a curvature it can have more or less than 180 degrees. So this isn’t a fine tuning problem on its own, if you would lived in a universe where triangles have less or more than 180 degrees it would represent a universe with negative or positive curvature. The issue with fine tuning is that the curvature of the universe is directly tied to the mass/energy density and any deviation from an extremely narrow range which our universe seems to sit in out of all possible values would not just produce a universe with triangles with fewer or more degrees than 180 but would either produce a universe that would collapse on itself within a blink of an eye or expand so fast that gravity would never be strong enough to cause even the most basic structures to form. So the issue really is that to produce a universe which will form galaxies and stars and survive long enough to produce life you need a lot of parameters at a certain very specific value even the smallest of deviations would not produce a universe that would ever support life, yet alone an intelligent life. What’s even stranger iirc is that the values have to be really what they are now you can’t simply 2X all of them to maintain the proportions and get the same result. And this is really what people are looking to solve, yes the androcentric is a solution if they were anything than what they are now we wouldn’t be here to discuss why, but the issue is that out of all other possible combinations you don’t seem to find another stable state and that is the true mystery.

coremoff 5y ago

somewhat related, I think, is the enormous disparity between the strength of the strong/week/electromagnetic forces and gravity (30 or 40 orders of magnitude); possible indication that there's something missing

tsimionescu 5y ago
Why is this a problem? If the other three forces were perfectly equal, or in regular intervals, maybe this would have meant something, but the other three forces' strength varies by x, y, z between them. Other than human intuition, there is nothing inherently different between x = 2 and x = 10^30-40.
- coremoff 5y ago
  I don't know that it's a problem, and I'm no expert; my understanding is that differences like that can sometimes indicate that there's something else at play
- MarkusQ 5y ago
  > there is nothing inherently different between x = 2 and x = 10^30-40 Fermat begs to differ. :)

throwawaylinux 5y ago

Isn't the whole thing made up to fit observation though? Why is that any more arbitrary than, say, electromagnetism existing?

TheOtherHobbes 5y ago
It's an explanatory theory with a lot - a lot - of gaps. It has been extended with some nice predictions like the Higgs. But basically it's a Franken-patchwork of math glued together quite awkwardly. Because that is what it is. Literally. It was developed by thousands of grad students and their supervisors throwing math at the wall and keeping anything that matched observations. So there was a lot of random searching involved. What's missing is a central guiding metaphor. Relativity has one. In comparison, the Standard Model is very epicycle-ish tool for calculating Lagrangians with plenty of "Yes but" and "Except when".
- throwawaylinux 5y ago
  I'm not sure I quite explained myself, although I do appreciate the reply. See, I also don't see how one central guiding metaphor would be any less arbitrary than none, or ten metaphors. What I am asking is why would α = 0.0072973525693 be more of a problem than electromagnetism or the speed of light being constant or e=mc^2? If the fine structure constant was exactly 1 would that make it better? Why is 1 less arbitrary or more good? I understand the beauty in simplicity, fewer concepts or ideas, smaller formulas explaining more things, 1 being "nicer" than other numbers, etc. So I understand that aspect of goodness, so it is the connection to underlying observable reality I'm asking about. Because isn't it also arbitrary to think that if we could explain things in more beautiful ways then it would be a deeper understanding or closer to the truth?
  - abrichr 5y ago
    It sounds like you're asking why parsimony is desirable in science. From https://aeon.co/essays/are-scientific-theories-really-better-when-they-are-simpler https://aeon.co/essays/are-scientific-theories-really-better...: > The upshot is that there are three parsimony paradigms that explain how the simplicity of a theory can be relevant to saying what the world is like: > Paradigm 1: sometimes simpler theories have higher probabilities. > Paradigm 2: sometimes simpler theories are better supported by the observations. > Paradigm 3: sometimes the simplicity of a model is relevant to estimating its predictive accuracy. > These three paradigms have something important in common. Whether a given problem fits into any of them depends on empirical assumptions about the problem. Those assumptions might be true of some problems, but false of others. Although parsimony is demonstrably relevant to forming judgments about what the world is like, there is in the end no unconditional and presuppositionless justification for Ockham’s Razor.