by chris-h » Thu 14 Oct 2004, 12:44:36
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2. Thermodynamics? well since you brought it up........
"energy cannot be destroyed or created" - really? you went back and checked how the universe began, if it did begin
That easy.
The universe started with an overall energy level of zero and its energy level is still zero.
Gravity has a negative energy since you need energy to get out of a gravity field.
The total energy of the universe is still zero.
Energy cannot be created or destroyed. First law is still valid.
For a more scientific analysis here
http://www.astrosociety.org/pubs/mercur ... thing.html$this->bbcode_second_pass_quote('', 'I')n the inflationary theory, matter, antimatter, and photons were produced by the energy of the false vacuum, which was released following the phase transition. All of these particles consist of positive energy. This energy, however, is exactly balanced by the negative gravitational energy of everything pulling on everything else. In other words, the total energy of the universe is zero! It is remarkable that the universe consists of essentially nothing, but (fortunately for us) in positive and negative parts. You can easily see that gravity is associated with negative energy: If you drop a ball from rest (defined to be a state of zero energy), it gains energy of motion (kinetic energy) as it falls. But this gain is exactly balanced by a larger negative gravitational energy as it comes closer to Earth’s center, so the sum of the two energies remains zero.
The idea of a zero-energy universe, together with inflation, suggests that all one needs is just a tiny bit of energy to get the whole thing started (that is, a tiny volume of energy in which inflation can begin). The universe then experiences inflationary expansion, but without creating net energy.
What produced the energy before inflation? This is perhaps the ultimate question. As crazy as it might seem, the energy may have come out of nothing! The meaning of "nothing" is somewhat ambiguous here. It might be the vacuum in some pre-existing space and time, or it could be nothing at all – that is, all concepts of space and time were created with the universe itself.