Hewerton22 wrote:Source of the post It's like the "atmosphere" of the object, right? But it's very dense.
No, it's just a boundary of no return.
Hewerton22 wrote:Source of the post It's like the "atmosphere" of the object, right? But it's very dense.
Hewerton22 wrote:Source of the post It's like the "atmosphere" of the object, right? But it's very dense.
Propulsion Disk wrote:Source of the post But anyway, so mass BENDS spacetime and doesn't stretch or shrink it, is that what the "relativity of simultaneity" is?
Propulsion Disk wrote:Source of the post Also, you say that 6x10-10 is the energy density of quantum flux which is hard to believe, I understand that there is a discrepancy between two different values for the energy density, but I argue that there is something that "cancels out" most of the energy to get your value, but in truth, the undisturbed energy density I say is 10e+113 J/m3 because if not, the zero-point energy of the flux is wrong, and several well proven theories are now wrong also.
Propulsion Disk wrote:Source of the post But thanks for the explanations, they really make you think, I guess relativity does that though.
Watsisname wrote:
Stellarator wrote:Source of the post If it doesn't make any sense, just keep re-watching it 'till it does.
Watsisname wrote:Stellarator wrote:Source of the post If it doesn't make any sense, just keep re-watching it 'till it does.
And ask questions, of course.
Watsisname wrote:Source of the post Propulsion Disk, the image was an animated gif, so perhaps that was the problem. I replaced with two static images, see if it shows up for you now.
Watsisname wrote:Source of the post Propulsion Disk wrote:Source of the post But anyway, so mass BENDS spacetime and doesn't stretch or shrink it, is that what the "relativity of simultaneity" is?Not quite. The relativity of simultaneity is a feature of special relativity, not requiring any mass or curvature. It basically means that two observers who are moving with respect to one another will disagree on whether two events are simultaneous, because of how space and time transform between their reference frames (the Lorentz transformations).
Stellarator wrote:Source of the post This particular video is probably the most important one to ever see if you want to understand causality and relativity, Propulsion Disk. If it doesn't make any sense, just keep re-watching it 'till it does.
Watsisname wrote:Source of the post 6x10sup {vertical-align: super; font-size: smaller;}-10 joules per cubic meter is the density of whatever sort of energy that is consistent with the observed acceleration of the universe. We don't know what that energy is exactly, but the simplest working model is that it is a sort of vacuum energy, because it has the same density everywhere and that density appears to remain constant over time despite the expansion. In general relativity, any energy density associated with the vacuum can be represented as a cosmological constant, which is that capital Lambda (Λ) in the ΛCDM model.We (cosmologists) are also confident that the value for the vacuum energy for the universe cannot be as large as 10sup {vertical-align: super; font-size: smaller;}113 J/msup {vertical-align: super; font-size: smaller;}3. If it was, it would break the universe very badly. A vacuum energy of even just 10sup {vertical-align: super; font-size: smaller;}-8 J/msup {vertical-align: super; font-size: smaller;}3 would be inconsistent with the universe starting out dense enough to form the CMB and also having its current age and expansion rate. This high of an energy density would also make the spacetime so strongly positively curved (like the 3D version of the surface of a sphere, or hypersphere) that light would make multiple circulations around the universe. We would see multiple images of the same objects all across the sky, as if living in a hall of mirrors. Going as high as 10sup {vertical-align: super; font-size: smaller;}113 J/msup {vertical-align: super; font-size: smaller;}3 becomes ridiculous. My computer can't even handle simulating it! So I agree completely with you, I think the solution to this problem must be that the vast majority of the vacuum energy density predicted by quantum field theory somehow cancels out to be consistent with cosmological observations.
Propulsion Disk wrote:Source of the post is that what he meant by "reversing the direction of your changing spacetime interval"
Stellarator wrote:Source of the post I could answer this question more thoroughly, but at risk of messing up my physics and embarrassing myself, I'll let Watsisname explain it instead. Suffice to say that I don't think a faster procession of time for one observer would radically change the space-time diagram, aside from shortening the intervals between events for one worldline by the amount it is ahead of other worldlines, since all time is relative.
Propulsion Disk wrote:Source of the post if you could somehow make time go faster, how would that look on the diagram?