Hi Roc, Sure. Let me go ahead and start by assuming that we need to exist in an environment that began in a state of low entropy (so that life can evolve during the "increasing entropy phase" - I could also examine this assumption, but that's another discussion...). GR then does some interesting things. First, gravity in GR couples to energy and momentum, and everything has energy and momentum, so, er, it couples to everything (binding them all together like the one ring I suppose). It can thus essentially "get everybody on the same page" when things are starting out - forcing "everybody" (all the particle species) to "pay attention" and synchronize their behavior...

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GR can then do something quite cool. If you feed the Einstein equations with a scalar field that happens to have much more potential energy than kinetic energy, then the spacetime responds by growing exponentially (i.e. the curvature is in the time direction - the spatial directions are driven to be very flat (i.e. the angles inside a triangle add up to 180 degrees), with the overall scale factor growing exponentially (i.e. the overall size of the triangle is growing exponentially in time)). Thus, consider some complex universe with a lot of entropy. Entropy is an extensive quantity, and thus if we consider some tiny volume element dV then there can't be much "stuff" inside dV, and therefore there is very little entropy inside dV. If we can get a scalar field inside that dV to satisfy the condition that its potential energy is much larger than its kinetic energy, then blammo, we get inflation and that dV region can grow larger than our Hubble volume in a tiny fraction of a second (and then scalar field can decay, ending inflation, to be followed by a "standard" big bang...). It is by no means an open and shut case - there are lots of details to be filled in - but I think the overall picture makes a lot of sense... Sincerely, Travis On Jun 2, 6:35 am, Roc <roc...@gmail.com> wrote: > nice answer. > could you elaborate on this, though? > > Why then should spacetime be curved? There are at least 2 good reasons: > > 1) it allows for a big bang to happen, thus "starting things off" in a state > > > of low entropy. > > thanks -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to everything-list@googlegroups.com. To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.