PieFedRegarding the dark energy debate/question, has anyone factored for the output of the stars themselves?
Disclaimer: I know enough about astronomy to know that I know pretty much nothing.
As dark energy was explained to me, it is a placeholder in the equation(s) for measuring the expansion of the universe. Rephrasing, we know the universe is expanding but we can’t account for some amount of the force involved.
I hope I am making sense and I am not too far out in the weeds.
To my question: all of the stars are blasting out not just photons but also substantial amounts of physical matter in various states (gas, plasma, solid) that also includes material from the various objects in the solar system (eg atoms of water from mars). Wouldn’t that mixture of massless photons and physical material have some significant influence on everything else?
Share on Mastodon
Share on Reddit
Share on WhatsApp
The problem is Dark Energy is the majority of energy in the universe, by ~3x (very roughly, I of course forget the exact proportions).
That immediately excludes ALL energy given off by stars/etc, as not only is it way more than would ever be possible, but traditional energies would DECREASE the expansion rate, not accelerate it.
There is also the massive problem of how it appears: between galaxies. NOT within galaxies, but on a larger scale. If it were caused by stars, it would be concentrated around denser galaxies, not literally the opposite of that.
I didn’t realize how significant the issue is, at most I was thinking maybe just barely double but not significantly beyond it.
On it being in the “empty” space or void between galaxies, could it be some of quirk of gravity? What I mean is that the absence of sufficient mass would lead to these voids “expanding”. Using the typical example of a stretched elastic sheet, the demonstration is to show how mass pulls space in upon itself. Except this would be the inverse with the mass collecting on the border of the void, causing it to be stretched apart instead.
Any chance you could recommend reading material on this?
Yes it ‘could’ be a misreading of how gravity works, but there is A LOT of math that shows Einstein’s general relativity is very accurate for describing spacetime. To the point that several recent studies completely exclude MOND (modified newtonian dynamics, that says it’s not unseen but misunderstood dynamics at larger scales) has recently been proven wrong.
Spacetime is VERY tough stuff in GR. Earth, and IIRC, even the Sun’s gravity well (before collapse), really produces time-bending forces over space-bending forces. ALL of the time dilation we see for GPS/etc is because time slows near mass. NOT because space bends towards mass. Space is VERY rigid. (hence why black holes were so ludicrous to scientists for a long while: They’re CRAZY dense)
I genuinely wish I had a good list of reading material. The best I can personally attest to is the PBS Space Time channel on YouTube that covers a ton of stuff from how GR evolves from Newtonian Dynamics to the latest questions of WTF kind of universe we live in. They’ve been spitting out videos for nigh a decade (or more?? I’m scared to check!) explaining everything, and the older videos that are just trying to catch people up to modern understanding are still excellent.