On Monday, October 28, 2019 at 7:21:40 PM UTC-5, Lawrence Crowell wrote: > > On Monday, October 28, 2019 at 8:24:39 AM UTC-6, John Clark wrote: >> >> On Sun, Oct 27, 2019 at 8:56 PM Alan Grayson <[email protected]> wrote: >> >> On Sunday, October 27, 2019 at 10:04:42 AM UTC-6, Lawrence Crowell wrote: >>> >>> *Quantum mechanics makes no particular prediction on the continuity of >>>> spacetime. If one equates the Schwarzschild radius with a Compton >>>> wavelength you get the Planck scale of 1.6x10^{-35}m. However, this really >>>> just tells us one is not able to locate a qubit in a region smaller than >>>> this scale. The Fermi and Integral spacecraft data on arrival times of >>>> different wavelengths of radiation from burstars indicates spacetime is >>>> smooth to two orders of magnitude smaller than the Planck length.* >>>> >>> >>> *> You're out of my depth here. If the Schwartzshild radius has one >>> value, and the Compton wavelength has another value, why would anyone want >>> to equate them? AG* >>> >> >> The Compton wavelength of a particle is just the wavelength light would >> have if the mass of the particle were converted to energy. As the >> wavelength gets smaller the energy gets larger, at some point the energy >> gets so high and the distance so small it turns into a Black Hole; that >> distance is the Planck length the time it takes light to move that distance >> is the Planck Time and the amount of mass required is the Planck Mass which >> is about the mass of a flea egg. The most acceleration anything can have >> is the Planck Acceleration, it is the amount of acceleration needed to move >> something from a speed of zero to the speed of light in the Planck Time, >> and the hottest that things can get is the Planck Temperature (1.4*10^32 >> Kelvin) because anything hotter would start radiating Black Holes instead >> of Blackbody Radiation. Or at least that's what Quantum Mechanics says, but >> if the evidence from the Fermi and Integral spacecraft holds up and >> spacetime really is smooth then something is wrong with this picture. >> >> John K Clark >> > > That is basically it. The Planck scale does not say that spacetime is > sliced and diced up into chunks. It just says that if you try to localize a > qubit onto a region smaller than √(Għ/c^3) ~ 1.6×10^{-35}m one gets a > quantum of black hole that conceals the qubit for a tiny time interval > √(Għ/c^5) ~ 5×10^{-44}sec before it explodes into a huge number of low mass > particles. It is a sort of Heisenberg microscope argument. > > The LQG machers were forced into a frantic fix on their loop theories that > had spacetime chopped up near the Planck scale. The data very much appears > to indicate that spacetime is not built up from chunks, but instead it may > be built from nonlocal quantum entanglements. So rather than spacetime > being a highly localized structure, with it might be added a lot of fine > tuning of variables, it is more an emergent phenomenon due to nonlocaly of > QM and entanglements. > > LC >
Of course space being made of "variables" vs. foam is a more mathematically Platonistic view. *Emergent 4-dimensional linearized gravity from spin foam models* https://arxiv.org/pdf/1812.02110.pdf <https://www.google.com/url?q=https%3A%2F%2Farxiv.org%2Fpdf%2F1812.02110.pdf&sa=D&sntz=1&usg=AFQjCNEvHw9-QxNM9tkpfXe2G2qqf4IB7Q> In this paper, we show for the first time that smooth solutions of 4-dimensional Einstein equation emerge from Spin Foam Models (SFMs) under an appropriate semiclassical continuum limit (SCL). @philipthrift -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/everything-list/638ce8ca-5d85-4cf1-8e40-66cdbd0015d1%40googlegroups.com.
