Big Bang Theory Primer

[Thief]

Once again the rate of expansion is seen to decrease with time due to radiation energy density.
.

last I heard .....the universe is expanding.....and GAINING speed

 

[sayak83]

last I heard .....the universe is expanding.....and GAINING speed

Yes. That is due to dark energy. To be covered in the next post.

 

[Thief]

Yes. That is due to dark energy. To be covered in the next post.

so the calculations for speed reduction are good for what?

 

[sayak83]

so the calculations for speed reduction are good for what?

There are three energy contributions to the universe. Mass, Radiation and Vaccum Energy. The first two decelerate and the last accelerate. The balance between the three helps us calculate and predict the expansion rate in the past and in the future. So all three are important for predictive science.

 

[Polymath257]

For a start you can try to calculate why the stars in galaxies all have the same orbital velocity around the galactic center, known as "the anomalous galactic rotation curve".

And what do you suggest? Modified gravity doesn't eliminate the need for dark matter. The gravitational lensing seen around galaxies and clusters also shows the existence of a source of gravity we don't see. And the amount required too explain the rotation curve also explains the lensing. Seems like we are using the universe too fit the calculations. As you wanted.

 

[Thief]

There are three energy contributions to the universe. Mass, Radiation and Vaccum Energy. The first two decelerate and the last accelerate. The balance between the three helps us calculate and predict the expansion rate in the past and in the future. So all three are important for predictive science.

and you might argue.....no central point
even though expansion would point back to it

 

[Thief]

There are three energy contributions to the universe. Mass, Radiation and Vaccum Energy. The first two decelerate and the last accelerate. The balance between the three helps us calculate and predict the expansion rate in the past and in the future. So all three are important for predictive science.

and the four items I grew up with are gone?

electromagnetism, gravity, the strong and weak forces

 

[Polymath257]

and you might argue.....no central point
even though expansion would point back to it

Except that it doesn't. The nature if the expansion us such that all locations see the same basic expansion away from them. All points have equal claim to being the 'center's.

 

[Polymath257]

and the four items I grew up with are gone?

electromagnetism, gravity, the strong and weak forces

Those are the four basic forces. The radiation, matter, and vacuum energy are what gravity is produced by. Radiation, for example, us mostly made of photons: e&m particles.

 

[`mud]

The only mathematical question that I have is:
what is the Cosmos expanding into ?
Or...must we accept that there is a `void or nothingness` out there ?
Or...must the `singularity` not have existed ?
Confused again am I !

 

[Thief]

Except that it doesn't. The nature if the expansion us such that all locations see the same basic expansion away from them. All points have equal claim to being the 'center's.

I see that as an illusion

so you think the universe was never held in one location

( if all current locations appear to be moving away from each other.....
there would still be that point of origin)

 

[Thief]

Those are the four basic forces. The radiation, matter, and vacuum energy are what gravity is produced by. Radiation, for example, us mostly made of photons: e&m particles.

last I heard....gravity need only have a substance to show itself

that is.....TWO items.....tugging upon each other

or perhaps you would say....the primordial singularity
was held in ONE location

the 'bang' remains a mystery for it's Cause

 

[Polymath257]

I see that as an illusion

so you think the universe was never held in one location

( if all current locations appear to be moving away from each other.....
there would still be that point of origin)

Nope. The only 'point of origin' is in the past.

last I heard....gravity need only have a substance to show itself

Mass, energy, momentum, all produce gravity. The issue is how much and how does that lead to the observed behavior. That's why dark matter and dark energy are required .

 

[Polymath257]

The only mathematical question that I have is:
what is the Cosmos expanding into ?
Or...must we accept that there is a `void or nothingness` out there ?
Or...must the `singularity` not have existed ?
Confused again am I !

We aren't expanding into anything. Space itself is expanding. The best answer mathematically is that we expand into the future .

 

[Native]

And what do you suggest? Modified gravity doesn't eliminate the need for dark matter. The gravitational lensing seen around galaxies and clusters also shows the existence of a source of gravity we don't see. And the amount required too explain the rotation curve also explains the lensing. Seems like we are using the universe too fit the calculations. As you wanted.

I suggest "gravity" to be quite removed from all equations since the forces in cosmic motions are all electromagnetic with both attractive and repulsive motions.
"Gravitational lensing" is nothing but a simple refraction phenomenon which scientists assume is "gravity".
Yes ve use calculations on many observations, but many cosmological assumptions are philosophically wrong which is why scientists adds metaphysical "dark this and that" in order to fit the Universe to their calculations and assumptions.

 

[Thief]

Nope. The only 'point of origin' is in the past.



Mass, energy, momentum, all produce gravity. The issue is how much and how does that lead to the observed behavior. That's why dark matter and dark energy are required .

It seems you have confused a value of 'time'......which does not exist
to the property of location

mass has gravity....as a property
gravity effects the other components
and should not be confused with the other components

 

[Thief]

I suggest "gravity" to be quite removed from all equations since the forces in cosmic motions are all electromagnetic with both attractive and repulsive motions.
"Gravitational lensing" is nothing but a simple refraction phenomenon which scientists assume is "gravity".
Yes ve use calculations on many observations, but many cosmological assumptions are philosophically wrong which is why scientists adds metaphysical "dark this and that" in order to fit the Universe to their calculations.

so .....you don't buy it.....dark matter....dark energy....

there's no proof except for numbers

I always thought it shallow to explain the universe by numbers
and insisting there is more dark 'stuff'......than the 'stuff' we can detect.....

seems an act of FAITH in numbers

 

[Polymath257]

I suggest "gravity" to be quite removed from all equations since the forces in cosmic motions are all electromagnetic with both attractive and repulsive motions.
"Gravitational lensing" is nothing but a simple refraction phenomenon which scientists assume is "gravity".
Yes ve use calculations on many observations, but many cosmological assumptions are philosophically wrong which is why scientists adds metaphysical "dark this and that" in order to fit the Universe to their calculations and assumptions.

Sorry, E&M simply doesn't explain what we see. For example, the type of fields required for the motions we see would produce polarizatio nd not seen.

We don't assume the lensing to be due to gravity. If it was refractio n, we would observe absorption lines in the spectra that are not there. Perhaps it is your philosophy that is wrong?

 

[Polymath257]

It seems you have confused a value of 'time'......which does not exist
to the property of location

mass has gravity....as a property
gravity effects the other components
and should not be confused with the other components

Well, I said it us the best possible answer. Even better is to note the question has no valid answer because it contains false views about the expsnsion.

 

[Polymath257]

so .....you don't buy it.....dark matter....dark energy....

there's no proof except for numbers

I always thought it shallow to explain the universe by numbers
and insisting there is more dark 'stuff'......than the 'stuff' we can detect.....

seems an act of FAITH in numbers

Well, I'm sorry you dont like accuracy and predictability, which is what numbers provide.