Is dark matter’s “nightmare scenario” true?
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Is dark matter’s “nightmare scenario” true?
1–10 of 183 posts
Re: Is dark matter’s “nightmare scenario” true?
#2Honestly, I hope so. The universe isn't totally amenable to our inspection, and it'd be nice to have an example that just stared us in the face all the time.
Re: Is dark matter’s “nightmare scenario” true?
#3I've been wondering for a while if light could be the thing that pushes away the boundaries of the universe and that's the reason for the expansion, if u can push a solar sail... anyways, I don't understand enough about this.
Re: Is dark matter’s “nightmare scenario” true?
#4If the title is a question, the answer is no.
Re: Is dark matter’s “nightmare scenario” true?
#5I've been wondering for a while if light could be the thing that pushes away the boundaries of the universe and that's the reason for the expansion, if u can push a solar sail... anyways, I don't understand enough about this.
There are no known boundaries of the universe. The universe expands everywhere continuously. I think of it as though a little bit of extra volume is injected in between everything on a regular basis. Also when we look out as far back in time as we can, everything looks very similar, and there's no "boundary". Each year we can see a little bit farther out into the universe because those photons from billions of years ago finally got to us and so far things keep looking the same the farther out we can see. So as far as we know the universe is far larger than what we can see (what has had enough time to send us photons). I also don't understand enough about this.
https://en.wikipedia.org/wiki/Expansion_of_the_universe https://en.wikipedia.org/wiki/Observable_universe
Re: Is dark matter’s “nightmare scenario” true?
#6I've been wondering for a while if light could be the thing that pushes away the boundaries of the universe and that's the reason for the expansion, if u can push a solar sail... anyways, I don't understand enough about this.
We can calculate the force exerted on an object by a photon of light of a given frequency. I'm guessing it is not sufficient to produce the effect you envisage, although I have not done the calculation. Interestingly this photon pressure does put an upper limit on the mass of a star; the Eddington Limit [1]. If a star is too large (and therefore luminous) its photon pressure pushes away other material and stops is from growing larger!
Re: Is dark matter’s “nightmare scenario” true?
#7Nightmare for who? How hard it is to admit that their equations are incorrect? Even amateur like myself can see that the dark matter is adhoc value that was calculated in order to patch the standard model. There are several better alternatives but do we need to wait until these stubborn believers have passed away until the world can move forward?
Re: Is dark matter’s “nightmare scenario” true?
#8I've been wondering for a while if light could be the thing that pushes away the boundaries of the universe and that's the reason for the expansion, if u can push a solar sail... anyways, I don't understand enough about this.
There are no known boundaries of the universe. The universe expands everywhere continuously. I think of it as though a little bit of extra volume is injected in between everything on a regular basis. Also when we look out as far back in time as we can, everything looks very similar, and there's no "boundary". Each year we can see a little bit farther out into the universe because those photons from billions of years…
But at the same time we're also racing away. There is light from objects that will never get to us because we're moving away from it, due to expansion, faster than it'd ever get to us.
Eventually we'll have moved so far away from everything that we'll start seeing less and less (granted, "we" likely won't be around, our planet having long since been incinerated when Sol dies).
Re: Is dark matter’s “nightmare scenario” true?
#9Nightmare for who? How hard it is to admit that their equations are incorrect? Even amateur like myself can see that the dark matter is adhoc value that was calculated in order to patch the standard model. There are several better alternatives but do we need to wait until these stubborn believers have passed away until the world can move forward?
At the moment there are no better alternatives that satisfy all the observations. If you try to replace General Relativity with something like Modified Newtonian Dynamics (MOND) [1], then you can get good fits to galaxy rotation curves. However, there are many sources of astronomical/cosmological data that will not bend to alternative gravity models, e.g the precise fluctuations of the cosmic microwave background put stringent bound on the matter components of the Universe.
[1] https://en.wikipedia.org/wiki/Modified_Newtonian_dynamics#Ou...
Re: Is dark matter’s “nightmare scenario” true?
#10Earlier quoted context omitted.
There are no known boundaries of the universe. The universe expands everywhere continuously. I think of it as though a little bit of extra volume is injected in between everything on a regular basis. Also when we look out as far back in time as we can, everything looks very similar, and there's no "boundary". Each year we can see a little bit farther out into the universe because those photons from billions of years…
But at the same time we're also racing away. There is light from objects that will never get to us because we're moving away from it, due to expansion, faster than it'd ever get to us. Eventually we'll have moved so far away from everything that we'll start seeing less and less (granted, "we" likely won't be around, our planet having long since been incinerated when Sol dies).
I think its likely we will be around in some form, though perhaps very different to how we see ourselves today.