5 ms·

If the "particles" don't have any mass, the "issues" you're assuming are likely irrelevant, as they would result in division by 0.

SpaceRaccoon 6y ago
But massless particles still have relativistic mass due to their velocity. That's why photons still have momentum and can exert pressure.
- rrobukef 6y ago
  Only if the particle has energy. This leaves the door open for information without energy. Quantum physics generally adds energy to measure. Though information should have energy, I can't say information must be either mass or light. So maybe there is a second relativistic effect for massless, lightless particles. /amateur scientist
  - pas 6y ago
    Doesn't this seem to violate thermodynamics? You need to fight entropy to encode information, which requires energy, right?
    - hilbert42 6y ago
      Good question, see if you can figure it out from the Landauer Principle links I've posted above (QM overload fatigue has set in from too many unresolved questions for one day, I'll worry about later). I must admit it makes sense, but ages ago when I first came across the notion that say a kilo of matter had a definite limit on the amount of information it can contain is a bit overwelming, especially so when one realises how huge that number is. That reminds me of a Feynman quote about there being 'pleanty of room at the bottom'.
      - pas 6y ago
        There's this limit https://en.wikipedia.org/wiki/Bremermann%27s_limit https://en.wikipedia.org/wiki/Bremermann%27s_limit that says that there's a maximum information processing throughput per kilogram of mass. There's this limit https://en.wikipedia.org/wiki/Bekenstein_bound https://en.wikipedia.org/wiki/Bekenstein_bound that describes the maximum density of information per area. So it seems if it would be possible to have/process information without energy those limits would be infinite. At least my layman reasoning leads me to believe this.
        hilbert42 6y ago
        "<...>a computer with the mass of the entire Earth operating at the Bremermann's limit could perform approximately 1075 mathematical computations per second.<...>" Yeah, right, it's a number so large on a human scale that it's essentially incomprehensible. However, if you think about it for a moment you can begin to imagine the enormity of the complexity. Leaving aside how you'd calculate said figure or dream about how it could ever be implemented, just try to consider the humongous amount of information that's contained in just one gain of sand. One must account for the amount of information contained within the configuration or quantum state of the trillions upon trillions of atoms and molecules along with all their constituent particles, electrons, protons, quarks—all of which contain information that's arisen from the quantum states of the various binding forces—the state of electromagnetic, strong and weak forces. Then there's information generated by the couplings and various physical characteristics of all the crystal lattices including all geometric information contained in each crystal's facets to be considered, not to mention various charges/interconnecting effects involved with crystal binding such as van der Waals forces and other quantum effects/fluctuations. Then we've also to consider all information generated from the sand grain's thermodynamic state (and that alone would be enormous). And that's not all, even information from phonon movement (noise) generated from within each crystal as well all noise coupled from external sources must be included. Vibrational/phonon energy, which in the real world is lossy, generates information from its dissipated thermal energy (even information is generated from the physical state/properties of matter that actually cause those losses). Thus, the total amount of information in just one grain of sand alone is simply mind-boggling. Now extrapolate all that to all those other grains of sand until we get to earth-size. And now also take into account the fact that when all those many grains are closely packed together, they generate even more information by virtue of their couplings (van der Waals forces now act between individual grains of sand, and so on and so on). 'Mind-boggling' doesn't come even close to describing the informational complexity!
  - hilbert42 6y ago
    Information is supposed to have mass by the Landauer mass-energy-information equivalence principle. Now some even reckon it stands the test: https://physics.aps.org/articles/v11/49 https://physics.aps.org/articles/v11/49 https://aip.scitation.org/doi/10.1063/1.5123794 https://aip.scitation.org/doi/10.1063/1.5123794
- eigenket 6y ago
  Photons do not have mass (their relativistic mass is zero). Momentum and pressure do not require mass to exist.
  - drdeca 6y ago
    Huh? Their rest mass is 0, but, they have energy, E = h * frequency iirc, so, shouldn't they therefore have a relativistic mass? (if one is going to use the concept relativistic mass at all that is)
    - deleted 6y ago
      [deleted]
    - dogma1138 6y ago
      No, relativistic mass in SR is dependent on the observer and it’s tied to the invariant mass if it’s 0 the relativistic mass is also 0. Photons have inertia not mass, or relativistic mass. The formula for relativistic mass is [invariant mass] / the square root of (1 - [speed of the observer]^2/C^2)
      - drdeca 6y ago
        That formula appears to say the the relativistic mass of a photon is 0/0 though?
        drdeca 6y ago
        I mean, because the relative velocity between the photon and the observer is always c.
        dogma1138 6y ago
        It doesn't work for photons, if you want to calculate the momentum (mass) of photons it will be planck's constant / λc. Going going by the standard relativistic mass calculation of SR alone m = γm0, γ = 1/[square root of (1 − v2/c2)], you get a division by zero which is well a no no, but this is where as you approach the speed of light your mass becomes infinite comes from.
hilbert42 6y ago
Agreed, I mentioned the mass aspect in my earlier post a few days ago but I got a bit sidetracked by alpha and other stuff and didn't explain what I meant very well. As I see it, the crucial aspect is whether or not the claim that the wavefunction collapses in a finite measurable time can be verified. If it can be measured then it seems to me that we then have to concern ourseles with all that other stuff, the electric constant, alpha and so on. That's a new ballgame, methinks.

SpaceRaccoon 6y ago

But massless particles still have relativistic mass due to their velocity. That's why photons still have momentum and can exert pressure.

rrobukef 6y ago
Only if the particle has energy. This leaves the door open for information without energy. Quantum physics generally adds energy to measure. Though information should have energy, I can't say information must be either mass or light. So maybe there is a second relativistic effect for massless, lightless particles. /amateur scientist
- pas 6y ago
  Doesn't this seem to violate thermodynamics? You need to fight entropy to encode information, which requires energy, right?
  - hilbert42 6y ago
    Good question, see if you can figure it out from the Landauer Principle links I've posted above (QM overload fatigue has set in from too many unresolved questions for one day, I'll worry about later). I must admit it makes sense, but ages ago when I first came across the notion that say a kilo of matter had a definite limit on the amount of information it can contain is a bit overwelming, especially so when one realises how huge that number is. That reminds me of a Feynman quote about there being 'pleanty of room at the bottom'.
    - pas 6y ago
      There's this limit https://en.wikipedia.org/wiki/Bremermann%27s_limit https://en.wikipedia.org/wiki/Bremermann%27s_limit that says that there's a maximum information processing throughput per kilogram of mass. There's this limit https://en.wikipedia.org/wiki/Bekenstein_bound https://en.wikipedia.org/wiki/Bekenstein_bound that describes the maximum density of information per area. So it seems if it would be possible to have/process information without energy those limits would be infinite. At least my layman reasoning leads me to believe this.
      - hilbert42 6y ago
        "<...>a computer with the mass of the entire Earth operating at the Bremermann's limit could perform approximately 1075 mathematical computations per second.<...>" Yeah, right, it's a number so large on a human scale that it's essentially incomprehensible. However, if you think about it for a moment you can begin to imagine the enormity of the complexity. Leaving aside how you'd calculate said figure or dream about how it could ever be implemented, just try to consider the humongous amount of information that's contained in just one gain of sand. One must account for the amount of information contained within the configuration or quantum state of the trillions upon trillions of atoms and molecules along with all their constituent particles, electrons, protons, quarks—all of which contain information that's arisen from the quantum states of the various binding forces—the state of electromagnetic, strong and weak forces. Then there's information generated by the couplings and various physical characteristics of all the crystal lattices including all geometric information contained in each crystal's facets to be considered, not to mention various charges/interconnecting effects involved with crystal binding such as van der Waals forces and other quantum effects/fluctuations. Then we've also to consider all information generated from the sand grain's thermodynamic state (and that alone would be enormous). And that's not all, even information from phonon movement (noise) generated from within each crystal as well all noise coupled from external sources must be included. Vibrational/phonon energy, which in the real world is lossy, generates information from its dissipated thermal energy (even information is generated from the physical state/properties of matter that actually cause those losses). Thus, the total amount of information in just one grain of sand alone is simply mind-boggling. Now extrapolate all that to all those other grains of sand until we get to earth-size. And now also take into account the fact that when all those many grains are closely packed together, they generate even more information by virtue of their couplings (van der Waals forces now act between individual grains of sand, and so on and so on). 'Mind-boggling' doesn't come even close to describing the informational complexity!
- hilbert42 6y ago
  Information is supposed to have mass by the Landauer mass-energy-information equivalence principle. Now some even reckon it stands the test: https://physics.aps.org/articles/v11/49 https://physics.aps.org/articles/v11/49 https://aip.scitation.org/doi/10.1063/1.5123794 https://aip.scitation.org/doi/10.1063/1.5123794
eigenket 6y ago
Photons do not have mass (their relativistic mass is zero). Momentum and pressure do not require mass to exist.
- drdeca 6y ago
  Huh? Their rest mass is 0, but, they have energy, E = h * frequency iirc, so, shouldn't they therefore have a relativistic mass? (if one is going to use the concept relativistic mass at all that is)
  - deleted 6y ago
    [deleted]
  - dogma1138 6y ago
    No, relativistic mass in SR is dependent on the observer and it’s tied to the invariant mass if it’s 0 the relativistic mass is also 0. Photons have inertia not mass, or relativistic mass. The formula for relativistic mass is [invariant mass] / the square root of (1 - [speed of the observer]^2/C^2)
    - drdeca 6y ago
      That formula appears to say the the relativistic mass of a photon is 0/0 though?
      - drdeca 6y ago
        I mean, because the relative velocity between the photon and the observer is always c.
        dogma1138 6y ago
        It doesn't work for photons, if you want to calculate the momentum (mass) of photons it will be planck's constant / λc. Going going by the standard relativistic mass calculation of SR alone m = γm0, γ = 1/[square root of (1 − v2/c2)], you get a division by zero which is well a no no, but this is where as you approach the speed of light your mass becomes infinite comes from.

hilbert42 6y ago

Agreed, I mentioned the mass aspect in my earlier post a few days ago but I got a bit sidetracked by alpha and other stuff and didn't explain what I meant very well. As I see it, the crucial aspect is whether or not the claim that the wavefunction collapses in a finite measurable time can be verified. If it can be measured then it seems to me that we then have to concern ourseles with all that other stuff, the electric constant, alpha and so on. That's a new ballgame, methinks.