9 ms·

Or maybe there's nothing wrong with the equations, they're just the wrong equations. Or based on a fundamentally wrong assumption.

fxj 1y ago
The equations that we already have are sufficient to describe the universe to 99.9999999% but they are a hodge podge of several different theories that all work very very well in their respective regime. QM + GR + Lambda CMD + ... But this just doesnt look nice to eye and the mind. The laws of nature "must" be shorter, more symmetric. Thats why we invented Superstrings which solves everything, but can never be tested... my 2 ct
- tsimionescu 1y ago
  QM and GR are mutually exclusive: if one is right, the other must be wrong (of course, it's very much still possible that both are wrong). If you use GR to predict the movement and interactions of photons in a medium, it's just wrong. If you use QM to predict the movement of light around a huge body, especially a black hole, it's just wrong. And what's worse, there is no limit or term you can add such that you could say "QM works only for objects up to size X, GR works for objects larger than size Y". Also, we're nowhere near explaining 99.99999999% of the behaviors we see in the universe. In fact, we're not even able to explain 6% of the things we see in cosmology - as is often explained, dark matter accounts for 27% of all energy in the universe, and dark energy for 68% - and we have no ideas what these actually are, if they exist at all.
  - fxj 1y ago
    Well, actually we have developed a very good feeling when to apply which theory. From subatomic particles to the large scale structure of the universe the right theories applied give us excellent results. lambda CDM models very well fit to the observed structures and the standard model describes all the particles that have been observed so far. We are desparately looking for effects that are unexplained by the standard model in particle physics so far. That is the reason why it is so difficult to justify yet another particle accelerator at CERN. my 2 cent
    - tsimionescu 1y ago
      Sure, we have a feeling for when to use one and when the other, but a feeling is not a physical theory. Also, the Lambda CDM literally doesn't explain what 95% of the universe is made of and how it behaves, it simply posits that it exists. So even if the Lambda CDM is perfectly correct, it's still extremely far from a complete model. Not to mention, the reason the tension between GR and QM is not very prominent is that we don't know how to conduct "medium scale" experiments, even though the vast majority of physical objects on Earth are in this medium scale: far too big to count particles, too small to measure observe gravitational bending effects. Basically, both QM and GR are completely useless for telling you what happens in compel scenarios like two billiards balls colliding on a frictionless table. They both have equations that are far too complex to actually solve for anything like this. And QM is even worse - even if you could solve the equation, it doesn't tell you what the balls will do, it only tells what chance they have atof being at some position with some velocity and spin if you were to measure that, whatever "measurement" might mean.
- nonrandomstring 1y ago
  > laws of nature "must" be shorter Coming at this from philosophy of science rather than as a physicist, I feel those quotes around "must". I think you also recognise how that might be a sort of "fundamentally wrong assumption". Imagine your words replayed 50 years in the future, not on physics but applied tp the problem of general AI/sentience. "The equations that we already have are sufficient to describe human thought to 99.9999999% but they are a hodge podge of several different theories...." Whereupon a psychologist/neuroscientist in any epoch would say: "Why on Earth are you looking for a *singular*, unified explanation of human experience?" What you can have is a set of "best they can be", internally self-consistent and well evidenced theories, none of which can ever fully explain the system - and that is the nature/feature of the system. Isn't that what Godel and Russell showed us?
  - TheOtherHobbes 1y ago
    It may be - probably is - a feature of the limits of our mental processes so far. But there's no good reason to assume the system itself just happens to mirror those limits. It would be very strange if the entire universe worked in inconsistent ways that matched the naive reasoning of some not very interesting animals on an ordinary star in the middle of nowhere.
    - nonrandomstring 1y ago
      We agree on human incompleteness. One limitation of recent tree-dwellers on utterly unremarkable small blue-green planets on the western spiral arm of the galaxy might be how we think about things like "consistent"? Or "knowable"? What if those things weren't a component of intelligence at all, but features a singularity which looks different depending on which side you approach it from? In maths, that's not even weird? [0] [0] https://cmsa.fas.harvard.edu/event/yip-2025/ https://cmsa.fas.harvard.edu/event/yip-2025/

fxj 1y ago

The equations that we already have are sufficient to describe the universe to 99.9999999% but they are a hodge podge of several different theories that all work very very well in their respective regime. QM + GR + Lambda CMD + ... But this just doesnt look nice to eye and the mind. The laws of nature "must" be shorter, more symmetric. Thats why we invented Superstrings which solves everything, but can never be tested... my 2 ct

tsimionescu 1y ago
QM and GR are mutually exclusive: if one is right, the other must be wrong (of course, it's very much still possible that both are wrong). If you use GR to predict the movement and interactions of photons in a medium, it's just wrong. If you use QM to predict the movement of light around a huge body, especially a black hole, it's just wrong. And what's worse, there is no limit or term you can add such that you could say "QM works only for objects up to size X, GR works for objects larger than size Y". Also, we're nowhere near explaining 99.99999999% of the behaviors we see in the universe. In fact, we're not even able to explain 6% of the things we see in cosmology - as is often explained, dark matter accounts for 27% of all energy in the universe, and dark energy for 68% - and we have no ideas what these actually are, if they exist at all.
- fxj 1y ago
  Well, actually we have developed a very good feeling when to apply which theory. From subatomic particles to the large scale structure of the universe the right theories applied give us excellent results. lambda CDM models very well fit to the observed structures and the standard model describes all the particles that have been observed so far. We are desparately looking for effects that are unexplained by the standard model in particle physics so far. That is the reason why it is so difficult to justify yet another particle accelerator at CERN. my 2 cent
  - tsimionescu 1y ago
    Sure, we have a feeling for when to use one and when the other, but a feeling is not a physical theory. Also, the Lambda CDM literally doesn't explain what 95% of the universe is made of and how it behaves, it simply posits that it exists. So even if the Lambda CDM is perfectly correct, it's still extremely far from a complete model. Not to mention, the reason the tension between GR and QM is not very prominent is that we don't know how to conduct "medium scale" experiments, even though the vast majority of physical objects on Earth are in this medium scale: far too big to count particles, too small to measure observe gravitational bending effects. Basically, both QM and GR are completely useless for telling you what happens in compel scenarios like two billiards balls colliding on a frictionless table. They both have equations that are far too complex to actually solve for anything like this. And QM is even worse - even if you could solve the equation, it doesn't tell you what the balls will do, it only tells what chance they have atof being at some position with some velocity and spin if you were to measure that, whatever "measurement" might mean.
nonrandomstring 1y ago
> laws of nature "must" be shorter Coming at this from philosophy of science rather than as a physicist, I feel those quotes around "must". I think you also recognise how that might be a sort of "fundamentally wrong assumption". Imagine your words replayed 50 years in the future, not on physics but applied tp the problem of general AI/sentience. "The equations that we already have are sufficient to describe human thought to 99.9999999% but they are a hodge podge of several different theories...." Whereupon a psychologist/neuroscientist in any epoch would say: "Why on Earth are you looking for a *singular*, unified explanation of human experience?" What you can have is a set of "best they can be", internally self-consistent and well evidenced theories, none of which can ever fully explain the system - and that is the nature/feature of the system. Isn't that what Godel and Russell showed us?
- TheOtherHobbes 1y ago
  It may be - probably is - a feature of the limits of our mental processes so far. But there's no good reason to assume the system itself just happens to mirror those limits. It would be very strange if the entire universe worked in inconsistent ways that matched the naive reasoning of some not very interesting animals on an ordinary star in the middle of nowhere.
  - nonrandomstring 1y ago
    We agree on human incompleteness. One limitation of recent tree-dwellers on utterly unremarkable small blue-green planets on the western spiral arm of the galaxy might be how we think about things like "consistent"? Or "knowable"? What if those things weren't a component of intelligence at all, but features a singularity which looks different depending on which side you approach it from? In maths, that's not even weird? [0] [0] https://cmsa.fas.harvard.edu/event/yip-2025/ https://cmsa.fas.harvard.edu/event/yip-2025/