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Earlier quoted context omitted.
Not a physicist by any means, but from the article it talks about gravity in the context of the graviton (as one plausible solution to the problem mentioned). Which is still hypothetical, so it's not like they've proven gravity from first principle or anything.
As a layman reading this, it’s funny. Because I do not need gravity proven to me from first principles ;)
The content of the article is very interesting and worth reading, but the framing feels circular. Some laws of nature are fundamental and other laws are inevitable consequences of those laws. If the inevitable laws were not inevitable, then they would be fundamental. As our knowledge and explanatory power grows, some laws that first appeared fundamental have been explained in terms of deeper laws, but we must still a…
Earlier quoted context omitted.
As a layman reading this, it’s funny. Because I do not need gravity proven to me from first principles ;)
Proven is the wrong word. You cannot prove a theory. Deriving a description of gravity from first principles would be more appropriate
I can certainly prove things about, say, addition.
Is that a typo, or is it really possible to have spin -0?
> When bootstrapping, physicists determine how elementary particles with different amounts of “spin,” or intrinsic angular momentum, can consistently behave. In doing this, they rediscover the four fundamental forces that shape the universe. They have derived gravity through quantum mechanics? What rock have I been living under?
"...bootstrappers find that many different spin-0 particles are possible." Is that a typo, or is it really possible to have spin -0?
The content of the article is very interesting and worth reading, but the framing feels circular. Some laws of nature are fundamental and other laws are inevitable consequences of those laws. If the inevitable laws were not inevitable, then they would be fundamental. As our knowledge and explanatory power grows, some laws that first appeared fundamental have been explained in terms of deeper laws, but we must still a…
But this itself is not strictly logical because changing the fundamental constants doesn't imply a change of the fundamental laws. The fundamental laws may very well work fine with different constants but we may just not be there to observe them in action because the outcomes may not result in a universe conducive to life (hence: anthropic principle).
As a bad analogy, physics affects an egg falling to the surface of a planet in low gravity in the same way as an egg falling in high gravity. The outcomes may be different, but the laws are the same. And of course, in the latter case it's less likely for something to survive the fall and live to even ask these questions in the first place.
There are some interesting possibilities that arise at this point. e.g. What if this Universe is only "somewhat" tuned for intelligent life? What if, on some more "appropriate" level of "tuning", more stable, fundamental particles are observable for longer periods of time yielding even more insight into the fundamental laws of the universe?
Lots of interesting stuff to talk about around a camp fire...
"...bootstrappers find that many different spin-0 particles are possible." Is that a typo, or is it really possible to have spin -0?
The content of the article is very interesting and worth reading, but the framing feels circular. Some laws of nature are fundamental and other laws are inevitable consequences of those laws. If the inevitable laws were not inevitable, then they would be fundamental. As our knowledge and explanatory power grows, some laws that first appeared fundamental have been explained in terms of deeper laws, but we must still a…
Assuming the existence of some abstraction called spin to derive the fundamental forces is a great exercise in internal consistency, but hardly meets any definition of "bootstrapping" as I understand the term.
The only theory I've ever encountered that passes this smell test to me is the mathematical universe hypothesis[0] because it's intuitive to me that math just "is" in some sense and does not require any upstream mechanisms or assumptions. As far as I'm concerned, if you have to assume the existence of anything whatsoever, it's not bootstrapping.
[0] https://en.wikipedia.org/wiki/Mathematical_universe_hypothes...
Wondering if anyone could recommend a layman's introduction to "spin". I've read the Wikipedia article, I broadly understand it, but just curious as to how it was discovered, why it is considered an "intrinsic" form of angular momentum, and why it is so fundamental a concept in our universe.
The way the book will describe it is from the perspective of group theory. If you assume that the laws of nature in a relativistic flat spacetime do not change under rotations, translations (in both space and time), and boosts (transformation between frames of reference of constant velocity), then these transformations define a Lie group called the Poincaré group. Representation theory then says that the representations of the Poincare group are characterized by two numbers. These two numbers are identified as a nonnegative mass and a spin. One interpretation is that these representations are indeed what "particles" are in Quantum Field Theory.