What is the Universe expanding into..

[Disco-Pete]

@ Discopete.

I see you are still quoting the entire previous post.

My lesson seems to have been in vain!

I'm a victim of instant gratification, and it appears, instant aggravation as well.😀

 

[Disco-Pete]

The fact that the night sky is not completely lit up by the almost infinite number of stars and galaxies in the universe has become known as "Olbers' Paradox".

I knew you were going to bring this up.

 

[Disco-Pete]

Aren't you paying attention?

LaPoint, who has since gone into hiding, was talking a lot of Sheetrock! 😛

Interestingly enough, others with unorthodox ideas that could upend and change the order of things so to speak have suddenly "gone into hiding" as well.

 

[MITsound]

The fact that the night sky is not completely lit up by the almost infinite number of stars and galaxies in the universe has become known as "Olbers' Paradox".

My science teach brought this up to me in 1981.
The answer I gave him is that photons radiate in all directions, like rays, from every star. Since stars are distant, very few rays are aimed at our eyes, and there are fewer as the stars become more distant from us. This makes it harder to see them, and I didn't view it as a paradox.
Now I think my 1981 answer, derived from a put on the spot 10 seconds consideration, isn't enough.

 

[N101N]

Coulomb came up with that back in 1785.

 

[MITsound]

Coulomb came up with that back in 1785.

So what?

 

[N101N]

So it`s been known for 235 years that radiation falls off with distance. No paradox, nor does it imply that the Universe is expanding.

 

[Galu]

So it`s been known for 235 years that radiation falls off with distance. No paradox, nor does it imply that the Universe is expanding.

I'm no cosmologist, but even I can see the contradiction in what you have just said.

The alternative to an expanding universe is a static universe of infinite size.

In such a universe, inverse square law of radiation not withstanding, there should be a continuous background wash of light in the night sky.

The fact that there isn't - which is the apparent paradox - can be explained if we accept that the universe is not static, but expanding.

Cosmologists are in agreement that the universe is expanding, the only debate is as to the rate at which it is expanding.

 

[N101N]

The phenomenological redshift, Doppler shift or whatever shift cannot reasonably imply that the Universe is expanding. The Universe is not expanding simply because it does not have a physical size, shape or structure. Also, such continuous system does not have a beginning or end. This may be extremely hard for people with a fixed mindset to accept.

 

[MITsound]

The phenomenological redshift, Doppler shift or whatever shift cannot reasonably imply that the Universe is expanding. The Universe is not expanding simply because it does not have a physical size, shape or structure. Also, such continuous system does not have a beginning or end. This may be extremely hard for people with a fixed mindset to accept.

So you are saying that the increasing distance between galaxies everywhere in general doesn't mean expansion.
I guess you mean space stays static, so every bit of matter in it must be contracting then, apparently increasing relative distances.

 

[Bill Coltrane]

The phenomenological redshift, Doppler shift or whatever shift cannot reasonably imply that the Universe is expanding.

Yes it can.

 

[kevinahcc20]

The phenomenological redshift, Doppler shift or whatever shift cannot reasonably imply that the Universe is expanding. The Universe is not expanding simply because it does not have a physical size, shape or structure. Also, such continuous system does not have a beginning or end. This may be extremely hard for people with a fixed mindset to accept.

A bold statement of rigid absolutes...please expand on your alternative explanation, the supporting mathematics and a few predictions made by your alternative model that would allow it to be tested. Perhaps you could also pass your magic bong around so that the rest of us mouth breathing droolers with fixed mindsets might be able to glimpse your lofty intellectual heights!

 

[N101N]

Oops, not exactly what you were taught at school?

 

[kevinahcc20]

Oops, not exactly what you were taught at school?

Interestingly the static model of the Universe was what I learned in school some 50 years ago.

 

[Galu]

The Universe is not expanding simply because it does not have a physical size, shape or structure. Also, such continuous system does not have a beginning or end. This may be extremely.hard for people with a fixed mindset to accept.

I see you offer no alternative explanation of why the night sky is not awash with light, other than to say that the light from distant astronomical objects is dim, which is, frankly, irrelevant.

The first Friedmann model of the expanding universe suggests that the universe is not infinite in space, but neither does it have a boundary. Gravity is so strong that spacetime is bent round on itself. However, in this model, gravity would eventually halt the expansion of the universe, leading to its collapse.

We can measure the velocities at which distant galaxies are moving away from us using the cosmological red shift. However, as I've conceded earlier, the distances to these galaxies are not well known as we can only measure them indirectly (cosmic candles and all that). So all we know for certain is that the universe is expanding. Cosmologists are still uncertain as to the influences affecting its rate of expansion - enter the search for evidence of the existence of dark matter.

You see, cosmologists are not the ones who have a fixed mindset. On the contrary, they are continually modifying their hypotheses to fit new observational data.

 

[N101N]

I did not say it`s static. Change is a prerequisite of physical existence.

 

[Galu]

"Reality leaves a lot to the imagination" - John Lennon

 

[Gyuri]

Dark Matter May Be Older Than The Big Bang, Study Suggests << News from The Johns Hopkins University

 

[Galu]

Thanks Gyuri. According to the article, the idea is not new, but theorists have now come up with a framework of mathematical calculations which support the idea. P.S. For 'mathematical' read 'beyond my ability to understand'! 🙂

This sentence interested me most: "We will soon learn more about the origin of dark matter when the Euclid satellite is launched in 2022". This prompted me to find out more about Euclid, and here is a summary of my findings:

Euclid is a space telescope which will orbit around the Sun, at an average distance of 1.5 million km beyond Earth’s orbit. This special location, known as the L2 Lagrangian point, keeps pace with Earth as we orbit the Sun.
Its objective is to understand the nature of dark energy and dark matter by accurate measurements of both the accelerated expansion of the Universe and the strength of gravity on cosmological scales.

More information here: ESA Science & Technology - Euclid

 

[Disco-Pete]

Electromagnetism can't substitute for the gravitational attraction of dark matter.

This is because the electromagnetic force caused by an electric dipole dies off quickly as the inverse of distance cubed, 1/r3, and not slowly as the inverse of distance squared, 1/r2, like gravity does.

So, on an astronomical scale, gravity dominates over electromagnetism.

Since either force can only be observed acting on an object, is it possible that when combined, the resulting force is greater than the sum of both separately? Is electromagnetic force considered a factor in cosmology?