Why can’t universe expansion be explained by…



The fact that subatomic particles are popping into existence and out of existence all the time in empty space? Wouldn’t the temporary presence of untold numbers of particles exert some influence on expansion? I haven’t heard any documentary or publication talk about this idea. Is it dumb?

In: Physics

As anyone on Earth who has ever thrown something up in the air can verify, gravity tends to pull objects down/towards the nearest large source of mass.

If you add up all of the mass in the known universe, the pull of that mass/it’s gravity should be slowing down universal expansion. Basically the stars should be starting to slow down by this point, with an eventual goal of stopping, and starting to fall back towards the center of the universe.

Instead, everything we’re observing makes it seem like the rate of expansion is actually increasing (the starts are moving faster and faster away). With everything we can see, and everything we know about physics, we have no idea what is causing this increase. Basically the universe is behaving the exact opposite of how it should, based on our current understanding.

Virtual particles, the particles you are referring to here, aren’t real. They arise as a mathematical trick in QFT. But even if they were real what would the effects be? Well they are particles with mass so total mass of the universe would increase. If mass increases so does gravity and we should see a slowing of expansion, not acceleration.

I don’t think this is a stupid idea.

If I recall correctly Lawrence Krauss in his book “A Universe from Nothing” uses this example as one of the possibilities of ‘where the universe came from. Specifically that the very first thing arouses from quantum fluctuation.

If we would add the assumption that in such energy density gravity starts being repulsive – this adds the source of expansion power.


Note that all this is more speculation than science ATM.