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Einstein made a small improvement to Newton. People seem think think this allows our current theories to be wrong..... Perhaps there might be small issues wit

Einstein made a small improvement to Newton. People seem think think this allows our current theories to be wrong..... Perhaps there might be small issues with Einstein theories, personally I doubt it, but, to me, I really don't think small fixes to the theory will explain this stuff away.

fibo 10y ago
Even if Einstein theory need a fix, some math achievements would keep valid: for example the Bianchi identities Einstein used.
madaxe_again 10y ago
It's not actually clear that there is any problem with current theory - it may just be that our understanding and application of it is incorrect. You can have a perfect mathematical model, but if just one of your premises is incorrect, the output can be nonsensical. I am a physicist (well, I studied as one, before going technology entrepreneur), and have always sat in the "dark matter is bullshit" camp - so my opinion is likely tainted. I think a far more likely explanation, as this paper could suggest, is that something far more mundane is happening. For instance, we already understand tidal forces - that bodies can become tidally locked, that there is an inertial frame shear that drags bodies along around a rotating centre of mass, and exchanges energy between an orbiting body and the centre.... So why is it infeasible that galaxies are tidally locked, and the lack of fall-off in radial velocity is down to the gravitational shear from the galactic core being far more intense than we anticipate, causing the behaviour we see. It doesn't require a rewrite of relativity, "just" of galactic evolution. Either that, or galaxies are sprites, and lazily rendered ones, at that.
- dnautics 10y ago
  I've half joked that dark matter might be cumulative IEEE floating point rounding errors.
  - adrianN 10y ago
    I hope God doesn't use IEEE floats.
    - aminorex 10y ago
      A Catholic one would.
- kmm 10y ago
  > For instance, we already understand tidal forces - that bodies can become tidally locked, that there is an inertial frame shear that drags bodies along around a rotating centre of mass, and exchanges energy between an orbiting body and the centre.... So why is it infeasible that galaxies are tidally locked, and the lack of fall-off in radial velocity is down to the gravitational shear from the galactic core being far more intense than we anticipate, causing the behaviour we see. It doesn't require a rewrite of relativity, "just" of galactic evolution. Because someone has indubitably already ran the numbers. The tidal force only has a non central, orbit changing influence on spatially extended bodies, and its effects even on objects as large as our solar system are completely negligible, as it doesn't seem to have a measurable effect on the orbits of the planets. The rotation curves are way off, which is a huge chunk of excess angular momentum that no tidal force can conjure. Where would it even come from, the rotational angular momentum of component stars?
  - madaxe_again 10y ago
    You're aware that mercury is tidally locked, as is our moon, mars' moons, and others? I would call those real, physical effects, not negligible. As to running the numbers - agreed - but one can get an answer which is correct but incorrect if your premises are incorrect. At a galactic scale the perturbations are likely tiny, but a tiny force applied over enough time adds up. Anyway. It's a poor example that's almost certainly wrong but my point was more about how a single incorrect assumption can wreck a model.
kowdermeister 10y ago
"a small improvement" I'd rather call it a paradigm shifting revolutionary idea ;)
hzhou321 10y ago
Acknowledge and embracing the assumption that the speed of light is a universal constant -- disregard of reference frame? And as a consequence, allowing space and time to curve? That is not a small fix. That is a fundamental faith jump.
scott_s 10y ago
If you look at the equations, relativity looks like a refinement to Newtonian physics: at small masses and low velocities, relativity makes the same predictions as Newtonian physics. However, it is not correct to call this a "small improvement." Relativity was a radical change to our understanding of how the universe behaves. In a Newtonian universe, information (including gravitation, electrical attraction, and light) travelled instantaneously. This does not happen in relativity, and nor does it happen in the universe we live in. Einstein did not merely improve upon Newton's work; Einstein proposed a theory which explained the ways in which we do not live in a Newtonian universe. Thomas Kuhn goes into this concept in detail in "The Structure of Scientific Revolutions."
- Keysh 10y ago
  There's nothing in Newtonian theory that requires light to travel instantaneously, and Ole Romer first demonstrated that light had a finite speed in the 1670s, roughly a decade before Newton published the "Principia".

fibo 10y ago

Even if Einstein theory need a fix, some math achievements would keep valid: for example the Bianchi identities Einstein used.

madaxe_again 10y ago

It's not actually clear that there is any problem with current theory - it may just be that our understanding and application of it is incorrect. You can have a perfect mathematical model, but if just one of your premises is incorrect, the output can be nonsensical. I am a physicist (well, I studied as one, before going technology entrepreneur), and have always sat in the "dark matter is bullshit" camp - so my opinion is likely tainted. I think a far more likely explanation, as this paper could suggest, is that something far more mundane is happening. For instance, we already understand tidal forces - that bodies can become tidally locked, that there is an inertial frame shear that drags bodies along around a rotating centre of mass, and exchanges energy between an orbiting body and the centre.... So why is it infeasible that galaxies are tidally locked, and the lack of fall-off in radial velocity is down to the gravitational shear from the galactic core being far more intense than we anticipate, causing the behaviour we see. It doesn't require a rewrite of relativity, "just" of galactic evolution. Either that, or galaxies are sprites, and lazily rendered ones, at that.

dnautics 10y ago
I've half joked that dark matter might be cumulative IEEE floating point rounding errors.
- adrianN 10y ago
  I hope God doesn't use IEEE floats.
  - aminorex 10y ago
    A Catholic one would.
kmm 10y ago
> For instance, we already understand tidal forces - that bodies can become tidally locked, that there is an inertial frame shear that drags bodies along around a rotating centre of mass, and exchanges energy between an orbiting body and the centre.... So why is it infeasible that galaxies are tidally locked, and the lack of fall-off in radial velocity is down to the gravitational shear from the galactic core being far more intense than we anticipate, causing the behaviour we see. It doesn't require a rewrite of relativity, "just" of galactic evolution. Because someone has indubitably already ran the numbers. The tidal force only has a non central, orbit changing influence on spatially extended bodies, and its effects even on objects as large as our solar system are completely negligible, as it doesn't seem to have a measurable effect on the orbits of the planets. The rotation curves are way off, which is a huge chunk of excess angular momentum that no tidal force can conjure. Where would it even come from, the rotational angular momentum of component stars?
- madaxe_again 10y ago
  You're aware that mercury is tidally locked, as is our moon, mars' moons, and others? I would call those real, physical effects, not negligible. As to running the numbers - agreed - but one can get an answer which is correct but incorrect if your premises are incorrect. At a galactic scale the perturbations are likely tiny, but a tiny force applied over enough time adds up. Anyway. It's a poor example that's almost certainly wrong but my point was more about how a single incorrect assumption can wreck a model.

kowdermeister 10y ago

"a small improvement" I'd rather call it a paradigm shifting revolutionary idea ;)

hzhou321 10y ago

Acknowledge and embracing the assumption that the speed of light is a universal constant -- disregard of reference frame? And as a consequence, allowing space and time to curve? That is not a small fix. That is a fundamental faith jump.

scott_s 10y ago

If you look at the equations, relativity looks like a refinement to Newtonian physics: at small masses and low velocities, relativity makes the same predictions as Newtonian physics. However, it is not correct to call this a "small improvement." Relativity was a radical change to our understanding of how the universe behaves. In a Newtonian universe, information (including gravitation, electrical attraction, and light) travelled instantaneously. This does not happen in relativity, and nor does it happen in the universe we live in. Einstein did not merely improve upon Newton's work; Einstein proposed a theory which explained the ways in which we do not live in a Newtonian universe. Thomas Kuhn goes into this concept in detail in "The Structure of Scientific Revolutions."

Keysh 10y ago
There's nothing in Newtonian theory that requires light to travel instantaneously, and Ole Romer first demonstrated that light had a finite speed in the 1670s, roughly a decade before Newton published the "Principia".