I am curious as to whether quantum particle-pair creation could be responsible for cosmological inflation. Question 1: Is there any theory about quantum particle-pair creation effect on local space-time? Obviously, where a particle exists there is gravitation, where no particle exists there is no gravitation. Quantum particle-pair creation must have some impact on the gravitational field and space-time. If gravity and space-time are equivilent, does particle-pair creation mean local spacetime expansion? Or is gravity and spacetime not as tightly related as I am supposing? Question 2: Is neutrino/anti-neutrino a valid candidate for quantum particle-pair creation? I only find electron/positron pairs mentioned in articles about quantum particle-pair creation. Perhaps there is there a reason that the quantum field does not create neutrino/anti-neutrino pairs? Question 3: For particle-pair creation to inflate the universe, very long-lived particles are required. Obviously electron/positron pairs would attracte and annihilate each other quickly. I thought maybe neutrino/antineutrino pairs might survive longer. However, none of this idea works if the neutrino has a short half-life. Is there any information available on the half-life of the neutrino or anti-neutrino?