On Tuesday, July 14, 2020 at 4:27:35 PM UTC-6, Brent wrote: > > > > On 7/14/2020 2:36 PM, Alan Grayson wrote: > > > > On Tuesday, July 14, 2020 at 2:50:12 PM UTC-6, Brent wrote: >> >> >> >> On 7/14/2020 12:22 PM, Alan Grayson wrote: >> >> >> >> On Tuesday, July 14, 2020 at 11:31:42 AM UTC-6, Brent wrote: >>> >>> >>> >>> On 7/14/2020 3:34 AM, Lawrence Crowell wrote: >>> >>> On Monday, July 13, 2020 at 6:30:46 PM UTC-5, Alan Grayson wrote: >>>> >>>> >>>> >>>> On Monday, July 13, 2020 at 5:19:30 PM UTC-6, Lawrence Crowell wrote: >>>>> >>>>> On Monday, July 13, 2020 at 4:42:24 PM UTC-5, Alan Grayson wrote: >>>>>> >>>>>> >>>>>> >>>>>> On Monday, July 13, 2020 at 1:42:49 PM UTC-6, Alan Grayson wrote: >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Monday, July 13, 2020 at 11:57:50 AM UTC-6, Brent wrote: >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> On 7/12/2020 11:50 PM, Alan Grayson wrote: >>>>>>>> >>>>>>>> There can be because it's consistent with the equations. A black >>>>>>>>> hole doesn't include any matter. General relativity is non-linear, >>>>>>>>> that's >>>>>>>>> why there can be non-flat cosmologies that contain no matter. Of >>>>>>>>> course >>>>>>>>> there may be some different, better theory in which spacetime can't >>>>>>>>> be >>>>>>>>> curved without matter...but it seems unlikely since we have good >>>>>>>>> evidence >>>>>>>>> that gravitational waves exist. >>>>>>>>> >>>>>>>>> Brent >>>>>>>>> >>>>>>>> >>>>>>>> Yes, good evidence that gravitational waves exist, but as far I >>>>>>>> know they're always associated with material interactions such as >>>>>>>> collisions of black holes. In the case of EM waves, I'd be more >>>>>>>> receptive >>>>>>>> of your claim that they can exist independent of charges and/or >>>>>>>> currents, >>>>>>>> but as far as I know there's no evidence of that. AG >>>>>>>> >>>>>>>>> >>>>>>>> But a collision of black holes does NOT involve matter. Black >>>>>>>> holes (as far as the theory goes) are purely geometric things, i.e. >>>>>>>> made of >>>>>>>> empty space. >>>>>>>> >>>>>>>> Brent >>>>>>>> >>>>>>> >>>>>>> How then does the BH at the center of our galaxy weigh in at 4 >>>>>>> million solar masses? AG >>>>>>> >>>>>> >>>>>> It's measured by observing the rotation rates of stars near the >>>>>> galactic core, and not so small by comparison with other BH's at the >>>>>> center >>>>>> of galaxies, called Super Massive BH's. AG >>>>>> >>>>> >>>>> It is unfortunately apparent that you are pretty highly confused by >>>>> some of this. You need to sit down and read a comprehensive book or text >>>>> on >>>>> GR and related subjects. It is not going to be possible to clear this up >>>>> with dozens of email posts. >>>>> >>>>> LC >>>>> >>>> >>>> About the EP; I merely stated that it demonstrates that acceleration is >>>> locally indistinguishable from gravity, and then I stated what "locally" >>>> means. This is what Wiki and other sources say. Yet you say I am >>>> confused. >>>> How so? About masses of BH's, I watch documentaries which feature >>>> astrophysicists offering their opinions, and they *uniformly* claim >>>> that BH's have mass. How could it be otherwise if they're remnants of >>>> massive collapsed stars? Not one makes Brent's claim, that they're just >>>> geometric manifestations. AG >>>> >>> >>> I didn't say they lacked mass. I said they lacked matter. Thus >>> countering your assumption that gravity requires matter. >>> >>> Brent >>> >> >> I could have said that gravity requires mass/energy. What's the >> distinction between matter and mass? TIA, AG >> >> >> Some things, e.g. black holes, have mass without matter (at least as far >> as GR goes). >> >> Brent >> > > What's the distinction between matter and mass? AG > > > What's your problem. Do you just want to argument semantics. I don't > care if you want to call a black hole "matter", but nobody else does. > Everybody else means localized packets of mass-energy in the form of > fermions. > > Brent >
Do I just want to argue semantics? No, of course not, But you seem to want that. Otherwise, instead of trying to put me down, you could have just assumed I meant MASS! IIRC, at some point above I did refer to E=mc^2, which equates MASS with energy. AG -- 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/94dc4c91-11a1-46a8-a565-4983c5e82285o%40googlegroups.com.
