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Interesting article. In lieu of any qualification to verify the claims; the comment section seemed on superficial reading populated with experienced scientists
by stareatgoats 9y ago
Interesting article. In lieu of any qualification to verify the claims; the comment section seemed on superficial reading populated with experienced scientists that gave some support.
Another takeaway was the introduction (for me) to the concept of "naturalness", with which the author has some issues. It is however not possible to do away with it (if I'm not mistaken about its meaning), except in cases where the assumptions of naturalness turn out to be wrong, as it seems it was in this case.
It seems to me that some concept of "naturalness", is what we use to interpret empirical facts, without which we could not make sense of it at all. Examples of what I would consider "naturalness": that the past precedes the present, that large things contain smaller things (perhaps in infinity), ad that small things are contained in larger things (perhaps in infinity), etc.
Granted, our sense of naturalness could be completely wrong, and empirical data constantly challenge what we consider natural, which is how it should be.
- platz 9y agoYour understanding of what naturalness is seems odd. If you get rid of naturalness, you just have fine tuning. Fine tuning is not beautiful but it is not a logical disaster as you describe.
- stareatgoats 9y agook thanks, on further investigation I realize my interpretation of "naturalness" was a laymans uninitiated one: "In physics, naturalness is the property that the dimensionless ratios between free parameters or physical constants appearing in a physical theory"[0] I have no idea what that means atm [0] https://en.wikipedia.org/wiki/Naturalness_(physics) https://en.wikipedia.org/wiki/Naturalness_(physics)
- auntienomen 9y agoIncomplete quote: '...dimensionless ratios between free parameters or physical constants appearing in a physical theory should take values "of order 1" and that free parameters are not fine-tuned.' It just means that theorists are suspicious of theories where the parameters have to be adjusted to high precision to match reality. That's reasonable grounds for suspicion, but it's not natural law.
- mikekchar 9y agoI'll take a stab (I Am Not A Physicist (in fact I couldn't handle the math and moved to CS ;-) ). Parameters or constants in a theory generally have units (i.e. speeds, density, whatever). But lots of things (usually ratios) have no units because they all cancel out. Those are called "dimensionless". Pi is dimensionless, as is e. What the naturalness property seems to be saying is that these dimensionless parameters (which you have to stick into the equations to make the math work out) should all be around the same order of magnitude and not require too much precision. If there is such a parameter that is super huge or super small (in relation to the others) or requires a lot of precision, it's an indication that the theory is incomplete. There should be an observable reason for that difference/precision. If I've gotten that right, then I can see why people would be sceptical of naturalness. If naturalness was correct, I would actually be curious of why it was correct.
- manyoso 9y agoMoreover, "naturalness" is not mathematically well-defined even though many of its most passionate proponents claim that it is. This is one of the primary objections that Sabine has of "naturalness", not only might it be wrong, but when you plumb the motivations for it and actually try to make it mathematically well-defined, the motivations turn out to all disintegrate.