Can the rotation of distant galaxies be explained without the use of Dark Matter and Energy?

[tar]

My thought is that the distance and size of distant galaxies is not taken into consideration when applying rotational and gravitational equations.

 

To apply the equation the rotation of the galaxy in question is considered as one thing rotating at once.

This is not what we see.    We see the closer parts of the galaxy 10s of thousands of years before the further parts.   

 

That is we cannot use one equation that takes the whole galaxy at once because we are seeing the galaxy at different times and any motion needs to be thusly "played back" to arrive at a position of the various stars at one moment where they were all in the same moment and then derive their positions in the next moment.

Regards, TAR

[Genady]

12 minutes ago, tar said:

My thought is that the distance and size of distant galaxies is not taken into consideration when applying rotational and gravitational equations.

 

To apply the equation the rotation of the galaxy in question is considered as one thing rotating at once.

This is not what we see.    We see the closer parts of the galaxy 10s of thousands of years before the further parts.   

 

That is we cannot use one equation that takes the whole galaxy at once because we are seeing the galaxy at different times and any motion needs to be thusly "played back" to arrive at a position of the various stars at one moment where they were all in the same moment and then derive their positions in the next moment.

Regards, TAR

Do you have a reference to this kind of miscalculation?

[tar]

Genady, 

My thought that the calculations are missing something is that they need dark matter to provide the extra mass to arrive at the observed rotation.

Imagine if there IS no such thing as dark matter and the observations are incorrectly interpreted.

it is easier in my thinking to discard imaginary dark matter and look for the manner in which the equations are misapplied.

Regards TAR

After all we don't notice any dark matter locally.   It is only noticed in the rotation of distant galaxies.   It is a device to true the equations.   Perhaps there is  another way to true the equations.

Optical illusions are possible.   

Things big look small far away.  Things very far away from each other look close to each other when they are at the same inclination and rotation but the one is 10lyrs from us and the other is 100ly.   Stars on the other side of the Galaxy are NOT where we see them.  They have traveled around the Milky Way for 10K years since they were in the position we see them in.

There are two different nows we should imagine.   One that includes the stars in the positions we see them and one that includes the stars in the position that a God would find them now.

the close part of a distant galaxy is in the position it was in 5 million years ago.  The further parts might be in a position they were in 5.01 

we do not know if gravity works instantaneously or whether it works over time.

Thusly you cannot use the same equation for gravitational rotation when you are looking at elements that are in a position at a defined time when they are no longer actually in that position.

 

We can imagine an arrangement all at once in our minds, but in actually light and probably gravity take time to travel across great distances.   One part of the image is not immediately known to the other part in reality as it is in the image in our minds.

[Genady]

22 minutes ago, tar said:

It is only noticed in the rotation of distant galaxies.

This is incorrect. It is noticed in the rotation of our own Milky Way.

[tar]

I have a foundational understanding that we build an analog version of the universe within the folds and synapses of our brain that we hold all at once, the whole universe at once.  However the universe does not happen all at once, it takes time for one part of it to reach another part.   Each point in the universe is surrounded by thje others at increasing distances and the far away stuff has not yet communicated its current position to us...etc.

 

The situation is we match external reality to our image of it that we build in our brains through what we see and hear and feel and smell and taste and deduce.

If your image of the world exactly matches what you sense you have it exactly right.

If a lot about the external world needs to change in order for your image to be correct your image is likely incorrect.

It is MUCH easier to adjust your image to match the world than to adjust the world to match your image.

Dark Matter is a made up thing.  Easier to discard it and bold an image that matches our senses.

 

Regards, TAR

18 minutes ago, Genady said:

This is incorrect. It is noticed in the rotation of our own Milky Way.

How so?  Are we assuming the distant parts of our galaxy are in the same time as the close parts?  

The dark matter is added because the equations don't come out right and the observed rotation requires more mass.   The dark matter is not observed.  It is proposed as being present to explain the rotation.

[Genady]

4 minutes ago, tar said:

Are we assuming the distant parts of our galaxy are in the same time as the close parts?

No, we are not. We know how to calculate the difference.

[tar]

dark matter is by definition not observed

4 minutes ago, Genady said:

No, we are not. We know how to calculate the difference.

Perhaps we know but perhaps not Genady.  For instance it is NOT usually mentioned whether we are considering the position of an observed star as it was when the light left it, as it appears to be now or as it actually is after traveling around the Millky Way center for the time it took the light to reach us.   Three different positions.  We perhaps know how to calculate the differences but what is the assumption being made by the calculator as to what is being held as the reference and what difference is being caluculated.  

Like I said, everything in your mind happens at the same time,  everything you observe already happened as long ago as the distance

[Genady]

7 minutes ago, tar said:

everything you observe already happened as long ago as the distance

It is well-known and taking it in consideration is so elementary that, as you've said,

8 minutes ago, tar said:

it is NOT usually mentioned

 

[tar]

Let me ask the question this way.

How many supernovas are there currently in our galaxy?

All depends on what you consider currently.  In actually the supernovas currently going on in our galaxy are not know to us.   It take their light thousands of years to get to us.  Astronomers 2 or 5 or 10k years from know will see them.

you are suggesting everyone already takes the time and distance into consideration but I know for a fact that people, scientists in particular use the word now and mean different things without "mentioning" what they are calling now.

 

[Genady]

2 minutes ago, tar said:

Let me ask the question this way.

How many supernovas are there currently in our galaxy?

All depends on what you consider currently.  In actually the supernovas currently going on in our galaxy are not know to us.   It take their light thousands of years to get to us.  Astronomers 2 or 5 or 10k years from know will see them.

What do supernovas have to do with the dark matter in our galaxy?

[tar]

actuality

 

[Genady]

4 minutes ago, tar said:

I know for a fact that people, scientists in particular use the word now and mean different things without "mentioning" what they are calling now.

Do they do so in research papers?

[tar]

Just now, Genady said:

What do supernovas have to do with the dark matter in our galaxy?

The whole idea of dark matter came about by studying the motion of a supernova in a distant galaxy

I use them here to point out that someone measuring the rotation of our galaxy based on a supernova is looking at a supernova that already happened here long ago.  We saw it long after it occurred and the other galaxy sees it long after we saw it.

Not sure.  I base my  concerns on stuff I have read in the past.   I mentioned some of what I am mentioining not on this forum years ago.  I do not know which of what I have said is currently incorporated into the calculations.

[Genady]

2 minutes ago, tar said:

The whole idea of dark matter came about by studying the motion of a supernova in a distant galaxy

This is incorrect. See Dark matter - Wikipedia.

[tar]

now on this forum not not on this forum.  Sorry.

Do you believe in two difffernent nows.   One that we observe and one that we imagine from a godlike perspective?

[Genady]

6 minutes ago, tar said:

one that we imagine from a godlike perspective

What are you talking about?

[tar]

Sorry but the article was not comprehensible to me.

I talked about motion in the early universe and later and now and miscalculations and previous definitions of dark matter and the expansion rate of the universe and such and I have no idea how they have come up with such things and what they are trying to say.

Bottom line, they seem to not have "found" the particle required to account for the dark matter they need in their velocity of rotation calculations.

This makes me double down on my speculation.  Perhaps they are trying to apply kepler's law concerning the solar system to the Galaxy and perhaps the size of the galaxy affects the gravity between the components in such a way as interactions are not instantaneous and the gravitational effects are delayed and speed of rotation is NOT as if a fixed connected disk is rotating but the gravitational "pulls" are at vectors related to where mass "was" not to where mass currently "is".

14 minutes ago, Genady said:

What are you talking about?

A consideration of mine that is not mainstream.

Relativity assumes there is no special frame of reference.

I assume that here and now is our special frame of reference and we can subtract and add back and such to figure what the orientation and arrangement of the universe around us is most likely currently like, as well as what is was like at various times in the past.

Nothing we see is current.  It is all old news, but we can imagine things progressing without us seeing their progression yet.

So if you imagine where a star you see in the night sky actually exists currently you are looking at it from a Godlike perspective.

[Genady]

5 minutes ago, tar said:

interactions are not instantaneous and the gravitational effects are delayed

It is all known for more than hundred years now and it is a part of calculations. After all the delays are taken into account, more mass is required for the motions to be what they are. Nobody calculates galaxy rotation "as if a fixed connected disk is rotating."

You do not have any basis to claim that astronomers do not take distances and times into account.

Can you show how your calculation makes a difference? I mean calculation, not words.

[tar]

57 minutes ago, Genady said:

No, we are not. We know how to calculate the difference.

do we know how to locate the actual position of a star currently, not the position it was in when the light we see tonight left it?

[Genady]

1 minute ago, tar said:

do we know how to locate the actual position of a star currently, not the position it was in when the light we see tonight left it?

See Relativity of simultaneity - Wikipedia.

[tar]

41 minutes ago, Genady said:

Do they do so in research papers?

 

27 minutes ago, Genady said:

What are you talking about?

 

4 minutes ago, Genady said:

It is all known for more than hundred years now and it is a part of calculations. After all the delays are taken into account, more mass is required for the motions to be what they are. Nobody calculates galaxy rotation "as if a fixed connected disk is rotating."

You do not have any basis to claim that astronomers do not take distances and times into account.

Can you show how your calculation makes a difference? I mean calculation, not words.

suppose a star is seen at vector A but is 10 ly away and has traveled in those 10years it took the light to reach us to vector B.    Does the Kepler equation used to figure the speed of rotation of the galaxy use vector A as the star's position or vector B?

2 minutes ago, Genady said:

See Relativity of simultaneity - Wikipedia.

Genady, I have mused on this quite a bit.  I have some relativity books downstairs and have discussed this on this forum in the past.

My thought is that one CAN assume simultaneity regardless of observer by positing the godlike perspective that puts everything in the universe currently existent at the age of the universe.

Of course we cannot see it because it take light time to get here.  We NEVER see the universe as it is presently, we always see it as it was when the light that left it, left it.

The "same" time is observer dependent and as you say an observer closer to the event sees it before an observer more distant, but the fact remains that the event occured already and other events other places in the universe occurred at that same moment.

Regards, TAR

[Genady]

7 minutes ago, tar said:

 

 

suppose a star is seen at vector A but is 10 ly away and has traveled in those 10years it took the light to reach us to vector B.    Does the Kepler equation used to figure the speed of rotation of the galaxy use vector A as the star's position or vector B?

A star in position A has velocity V. This does not depend on when it happens or when we observe it. 

[tar]

Genady,

We cannot know the position and velocity of a particle such as an electron of an atom with certainty.

what makes you think we can know the position and velocity of a star with certainty?

[Genady]

3 minutes ago, tar said:

Genady,

We cannot know the position and velocity of a particle such as an electron of an atom with certainty.

what makes you think we can know the position and velocity of a star with certainty?

The scale of this uncertainty is Planck's constant. It is too small to affect calculations for stars.

[Ghideon]

9 minutes ago, tar said:

We cannot know the position and velocity of a particle such as an electron of an atom with certainty.

what makes you think we can know the position and velocity of a star with certainty?

Are you referring to the Heisenberg uncertainty principle? 

If so, what makes you think that it has a practical impact on scientists abilities to measure positions and velocities of macroscopic objects such as stars? 

(edit: x-post with @Genady )

Edited 9 hours ago by Ghideon
x-post