91–100 of 408 posts
I never liked that the physics community shifted from 'high energy' particle physics (the topic of the article) to referring to this branch as just 'particle physics' which I think leaves the impression that anything to do with 'particles' is now a dead end. Nuclear physics (ie, low/medium energy physics) covers diverse topics, many with real world application - yet travels with a lot of the same particles (ie, quark…
Isn't it the mathematics that is lagging? Amplituhedron? Higher dimensional models? Fun fact: I got to read the thesis of one my uncles who was a young professor back in the 90's. Right when they were discovering bosons. They were already modelling them as tensors back then. And probably multilinear transformations. Now that I am grown I can understand a little more, I was about 10 years old back then. I had no idea…
Tensors are like 200 years old in mathematics. Gauss talked about Tensors.
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Even better, there are the "nightmare" scenarios where dark matter can only interact gravitationally with Standard Model particles.
Personally—and this is where I expect to lose the materialists that I imagine predominate HN—I think we are already in a nightmare scenario with regard to another area: the science of consciousness. The following seem likely to me: (1) Consciousness exists, and is not an illusion that doesn't need explaining (a la Daniel Dennett), nor does it drop out of some magical part of physical theory we've somehow overlooked u…
I am sure others will say it better, but the cat-in-the-box experiment is a shockingly bad metaphor for the idea behind quantum states and observer effect. I will commit the first sin, by declaring without fear of contradiction the cat actually IS either alive or dead. it is not in a superposition of states. What is unknown is our knowledge of the state, and what collapses is that uncertainty. If you shift this to th…
[0] Well, and the hidden variables are non-local, which is a whole 'nother can of highly non-intuitive worms.
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One argument (while unsatisfying) is there are trillions of possible configurations, but ours is the one that happened to work which is why we're here to observe it. Changing any of them even a little bit would result in an empty universe.
There’s a name for that: the Anthropic principle. And it is deeply unsatisfying as an explanation. And does it even apply here? If the charge on the electron differed from the charge on the proton at just the 12th decimal place, would that actually prevent complex life from forming. Citation needed for that one. I agree with OP. The unexplained symmetry points to a deeper level.
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This is your regular reminder that epicycles were not an incorrect theory addition until an alternative hypothesis could explain the same behavior without requiring them.
Sure, but in that regard dark matter is even more unsatisfying than (contemporary) epicycles, because not only does it add extra complexity, it doesn't even characterize the source of that complexity beyond its gravitational effects.
But this might be easier to read: https://www.space.com/astronomy/black-holes/did-astronomers-...
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Doesn't that imply our theories are "good enough" for all practical purposes? If they're impossible to empirically disprove?
Typically whenever you look closely at an object with complex behavior, there is a system inside made of smaller, simpler objects interacting to produce the complexity. You'd expect that at the bottom, the smallest objects would be extremely simple and would follow some single physical law. But the smallest objects we know of still have pretty complex behavior! So there's probably another layer underneath that we don…
Incompleteness is inherent to our understanding as the universe is too vast and endless for us to ever capture a holistic model of all the variables.
Gödel says something specific about human axiomatic systems, akin to a special relativity, but it generalizes to physical reality too. A written system is made physical writing it out, and never complete. Demonstrates that our grasp of physical systems themselves is always incomplete.
I am sure others will say it better, but the cat-in-the-box experiment is a shockingly bad metaphor for the idea behind quantum states and observer effect. I will commit the first sin, by declaring without fear of contradiction the cat actually IS either alive or dead. it is not in a superposition of states. What is unknown is our knowledge of the state, and what collapses is that uncertainty. If you shift this to th…
There are various theories about what's actually happening in quantum mechanics. Some theories have hidden variables, in which case the issue is simply one of measurement (i.e. there really is an "objectively correct" value, but it only looks to us like there isn't).[0] However, this is not known to be the case, and many theories really do claim that position and momentum fundamentally cannot both be well-defined at…
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Newtonian physics is good enough for almost everything that humans do. It's not good for predicting the shit we see in telescopes, and apparently it's not good for GPS, although honestly I think without general relativity, GPS would still get made but there'd be a fudge factor that people just shrug about. For just about anything else, Newton has us covered.
quantum mechanics (also very much not Newtonian) is much more important to our day-to-day lives.