- #1
Helios
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Questions I have arrive from other forum by request.
I asked: Why can't an infinite motionless lattice be stable or even possible?
We set the stage with an infinite lattice and an exactly zero cosmo-constant ( which I gather results in infinite Minkowski space ) universe, what happens? Can't a lattice be stable if it is balanced with just the right negative pressure from a vacuum or some other agent? I thought this was stasis in the Gen.Rel. context.
Peter Donis Says:
"(1) If there is no cosmological constant, the stress-energy of the objects in the lattice will produce attractive gravity, meaning the lattice can't remain motionless for more than an instant."
Here I am confused. I must be misunderstanding the cosmological constant. If there is no cosmological constant then it equals zero. If the stress-energy of the objects in the lattice produce attractive gravity, then it does not equal zero. This seems like a contradiction.
Peter Donis Says:
"(2) If there is a cosmological constant, the lattice can be motionless for more than an instant if the repulsive gravity due to the cosmological constant exactly cancels the attractive gravity of the objects in the lattice; but this can only be the case for a finite lattice."
Here I am again confused. If the repulsive gravity due to the cosmological constant exactly cancels the attractive gravity of the objects in the lattice, then why doesn't the cosmological constant equal zero? What afflicts an infinite lattice that does not afflict a finite lattice when a finite lattice can be so large as to be indistinguishable from an infinite lattice?
I gather here that the lattice objects are not mere dust, but carry information requiring nonzero stress-energy. If the vacuum has nonzero stress-energy, does it also carry information? Is there vacuum information and can it stabilize our lattice?
I asked: Why can't an infinite motionless lattice be stable or even possible?
We set the stage with an infinite lattice and an exactly zero cosmo-constant ( which I gather results in infinite Minkowski space ) universe, what happens? Can't a lattice be stable if it is balanced with just the right negative pressure from a vacuum or some other agent? I thought this was stasis in the Gen.Rel. context.
Peter Donis Says:
"(1) If there is no cosmological constant, the stress-energy of the objects in the lattice will produce attractive gravity, meaning the lattice can't remain motionless for more than an instant."
Here I am confused. I must be misunderstanding the cosmological constant. If there is no cosmological constant then it equals zero. If the stress-energy of the objects in the lattice produce attractive gravity, then it does not equal zero. This seems like a contradiction.
Peter Donis Says:
"(2) If there is a cosmological constant, the lattice can be motionless for more than an instant if the repulsive gravity due to the cosmological constant exactly cancels the attractive gravity of the objects in the lattice; but this can only be the case for a finite lattice."
Here I am again confused. If the repulsive gravity due to the cosmological constant exactly cancels the attractive gravity of the objects in the lattice, then why doesn't the cosmological constant equal zero? What afflicts an infinite lattice that does not afflict a finite lattice when a finite lattice can be so large as to be indistinguishable from an infinite lattice?
I gather here that the lattice objects are not mere dust, but carry information requiring nonzero stress-energy. If the vacuum has nonzero stress-energy, does it also carry information? Is there vacuum information and can it stabilize our lattice?