3 ms·

You could not practically ever measure the difference in a lab, but it’s still a real effect. Look up the stress-energy tensor. I could equivalently say that a

You could not practically ever measure the difference in a lab, but it’s still a real effect. Look up the stress-energy tensor. I could equivalently say that a spinning ball weighs more than the same ball when stationary.

throw1234651234 6y ago
W=mg Weight is mass times gravity. It is the mass of the object. As affected by a single force - gravity. Gravity is a force. A spinning ball has ANOTHER force acting on it, and therefore cannot be defined by "weight". In short, this is an absurd statement that tries to redefine a scientific definition for...I don't even know? Sensationalism?
- Xcelerate 6y ago
  You are not considering the effect of general relativity. See theoretical physicist Professor Matt Strassler's page where he gives the exact same example of how energy can be stored that I did: https://profmattstrassler.com/articles-and-posts/particle-physics-basics/mass-energy-matter-etc/mass-and-energy https://profmattstrassler.com/articles-and-posts/particle-ph.... All forms of energy, including potential energy in the form of a compressed/stretched spring, couple to the gravitational field. Again, read about the stress-energy tensor for how this works. > In short, this is an absurd statement that tries to redefine a scientific definition for...I don't even know? Sensationalism? What I've said is not even remotely controversial in the physics community. Don't take my word for it; ask anyone who has taken a basic graduate course in general physics and they will agree that a compressed spring or a spinning ball weighs an imperceptibly (i.e., immeasurably) small amount more than the uncompressed spring or stationary ball, should you have a hypothetical scale that was so precise as to be able to measure the difference.
  - throw1234651234 6y ago
    Will read and come back, maybe I am missing something. Thanks.
- jabirali 6y ago
  You’re assuming the Newtonian theory of gravity, the parent poster uses Einstein’s general relativity. These theories disagree on quite a lot; e.g. general relativity predicts that light is affected by gravity, while Newton’s theory would not since photons are massless particles. Einstein was proven right here too. Note however that the quoted effect – difference in weight between a compressed and uncompressed spring – will realistically be so small that I doubt you could measure that in a lab. To get a sense of how small that effect is, try comparing the E=mc^2 mass-energy of a spring to its E=kx^2 compression energy...
  - throw1234651234 6y ago
    Will look into all of this, thanks.

throw1234651234 6y ago

W=mg Weight is mass times gravity. It is the mass of the object. As affected by a single force - gravity. Gravity is a force. A spinning ball has ANOTHER force acting on it, and therefore cannot be defined by "weight". In short, this is an absurd statement that tries to redefine a scientific definition for...I don't even know? Sensationalism?

Xcelerate 6y ago
You are not considering the effect of general relativity. See theoretical physicist Professor Matt Strassler's page where he gives the exact same example of how energy can be stored that I did: https://profmattstrassler.com/articles-and-posts/particle-physics-basics/mass-energy-matter-etc/mass-and-energy https://profmattstrassler.com/articles-and-posts/particle-ph.... All forms of energy, including potential energy in the form of a compressed/stretched spring, couple to the gravitational field. Again, read about the stress-energy tensor for how this works. > In short, this is an absurd statement that tries to redefine a scientific definition for...I don't even know? Sensationalism? What I've said is not even remotely controversial in the physics community. Don't take my word for it; ask anyone who has taken a basic graduate course in general physics and they will agree that a compressed spring or a spinning ball weighs an imperceptibly (i.e., immeasurably) small amount more than the uncompressed spring or stationary ball, should you have a hypothetical scale that was so precise as to be able to measure the difference.
- throw1234651234 6y ago
  Will read and come back, maybe I am missing something. Thanks.
jabirali 6y ago
You’re assuming the Newtonian theory of gravity, the parent poster uses Einstein’s general relativity. These theories disagree on quite a lot; e.g. general relativity predicts that light is affected by gravity, while Newton’s theory would not since photons are massless particles. Einstein was proven right here too. Note however that the quoted effect – difference in weight between a compressed and uncompressed spring – will realistically be so small that I doubt you could measure that in a lab. To get a sense of how small that effect is, try comparing the E=mc^2 mass-energy of a spring to its E=kx^2 compression energy...
- throw1234651234 6y ago
  Will look into all of this, thanks.