Some questions for better understanding of Main Stream Cosmology

[origin]

But we certainly do have Red Shift due to Gravity. Refer to Pound Rebka experiment, which could observe red shift due to gravity attraction on Earth. The point is if they could see a very small fraction of Red Shift on Earth, then the photon which is travelling millions of years and passing through various Gravitational Zones will certainly get nicely hammered on both the sides (Red - Blue)... do not tell me that it will neutralize.

I know this is all new to you, but there are "standard candles" that allow astronomers to know how far distant objects are and the red shift from those distant objects agree with the standard candle distance. There is no issue with graviational red shift. If you expended a little bit of effort you would be able to learn about the red shift and why gravitationl red shift is negligable. Oh and in general the red and blue shift from gravity will cancel out.

Moreover the Great dark matter Halo also won't leave photon unscathed, at least on Gravitational aspect ( do not confuse with no interaction of Photon with Dark Matter - We are talking about Gravitational Shift).

The amount of blue shifting from the graviation of our galaxy (dark matter and all) is negligable. So now you accept that dark matter is a viable theory! Well, at least you have learned something.

Also I could not see any integration calculations of Red Shift from a remote Galaxy, it should be done because cosmological expansion is present everywhere. The red shift is simply treated as that happened with d = galaxy start point space.

No matter how many time you state this misunderstanding of yours, it will remain an incorrect assumption. The red shift is from the expansion of the universe along the photons entire distance of traveled.

 

[origin]

What is correct about that weird explanation ?? In the red shift we are not talking about change in energy once it collides with Earth (collide = just to equate with your weirdo), while the example which you have given is simple elementary Physics, hence the friendly advise. You should have safely kept this Energy Conservation conundrum to relativity only like Aqueous did. Because there is no better explanation.

I should have assumed that you would not be able to understand the point, but I thought I would try.:shrug:

 

[PhysBang]

I know this is all new to you, but there are "standard candles" that allow astronomers to know how far distant objects are and the red shift from those distant objects agree with the standard candle distance. There is no issue with graviational red shift. If you expended a little bit of effort you would be able to learn about the red shift and why gravitationl red shift is negligable. Oh and in general the red and blue shift from gravity will cancel out.

If one takes a look at the papers where redshift is a factor, one can see the immense work that goes into trying to figure out the origin of the redshift for particular observations and for observations in general. Many papers run simulations to determine the chance that their observations are influenced by red or blue shifts that are not cancelled out and what the likely influence is if the shifting is not cancelled out.

If one suspects that there might be this kind of influence, one can sit down and work through just how much that influence could possibly be. In many ways, this is exactly the job of the physicists working in cosmology: to come up with the possible confounding factors and work out just how much this factor could influence their results. Because this is the job, paper after paper, especially the Nobel-Prize-winning papers, are filled with calculations of the possible confounding factors along with references to other papers that do nothing but work out confounding factors. So far, I believe that every objection to cosmological claims that I have seen on the internet has been worked out in detail by a cosmologist and addressed. I even think that both weirder and more damning objections to cosmology have been raised in the mainstream papers than I have seen on the internet.

 

[paddoboy]

Not sure why paddoboy wrote this.

He seems to be saying that you will not see a redshift from expansion due to gravity, but that does not fit with what he has previously said about cosmology. Lets wait to see his response.

I'm saying that the expansion of spacetime we see at large scales, is not obvious at smaller scales such as local galactic groups, and clusters of groups due to gravity's overwhelming attraction due to mass/energy densities of those regions.
This seems to be a real problem for Rajesh to accept.

 

[origin]

I'm saying that the expansion of spacetime we see at large scales, is not obvious at smaller scales such as local galactic groups, and clusters of groups due to gravity's overwhelming attraction due to mass/energy densities of those regions.
This seems to be a real problem for Rajesh to accept.

Agreed on both points.

 

[Farsight]

I'm saying that the expansion of spacetime we see at large scales

Spacetime doesn't expand, space expands.

And note that in gravitational redshift, the photon doesn't actually lose any energy. It appears to, but it doesn't. Conservation of energy applies to gravitational redshift, and gravitational blueshift. I know that this isn't what you read on websites or in textbooks, but they're wrong. You can work this out for yourself by imagining a 511keV photon falling into a black hole. The black hole mass increases by 511keV/c², not by a gazillion tonnes.

 

[RajeshTrivedi]

Whats happening to this forum ?? Only boys with half cooked knowledge from internet are responding to questions, a querist can be pardoned for asking silly questions, but self assumed "Know ALL" cannot afford to answer loosely. So much of silly responses and on top of that arrogance to the extent that the person who asks the question is either termed as having an agenda or declared illiterate.

 

[RajeshTrivedi]

The amount of blue shifting from the graviation of our galaxy (dark matter and all) is negligable. So now you accept that dark matter is a viable theory! Well, at least you have learned something.

Huh!

Days are not so bad for mainstream cosmology that people will have to be trapped to accept that.

They are certainly wonderful theories and great concepts calling for tremendous amount of hard work and intelligence. But you and couple of other people should learn more and be more careful when responding to questions. You guys are working on incorrect premises that you have to defend it, That is not expected of you and neither it falls in your domain, you just have to respond to questions. Theory will automatically defend itself in due course.

 

[paddoboy]

Spacetime doesn't expand, space expands.

Crap...spacetime certainly does expand.

And note that in gravitational redshift, the photon doesn't actually lose any energy. It appears to, but it doesn't. Conservation of energy applies to gravitational redshift, and gravitational blueshift. I know that this isn't what you read on websites or in textbooks, but they're wrong. You can work this out for yourself by imagining a 511keV photon falling into a black hole. The black hole mass increases by 511keV/c², not by a gazillion tonnes.

Your arrogance and audacity is only matched by your obvious delusions of grandeur and erronious conclusions.

 

[origin]

You guys are working on incorrect premises that you have to defend it,

Like what?

 

[paddoboy]

Whats happening to this forum ?? Only boys with half cooked knowledge from internet are responding to questions, a querist can be pardoned for asking silly questions, but self assumed "Know ALL" cannot afford to answer loosely. So much of silly responses and on top of that arrogance to the extent that the person who asks the question is either having an agenda or an illiterate.

You have it arse up.
The problem is the questions themselves, some which have been answered over and over, but not to your satisfaction, others that are just not creating the problems in cosmology that you so fanatically want to see them as doing..
Then you say you do not have an agenda?
As origin has said a few times, if you are interested in accepted mainstream cosmology, do some reading, but that doesn't seem to be the case now does it?...Hence that agenda again.

 

[paddoboy]

You guys are working on incorrect premises that you have to defend it, That is not expected of you and neither it falls in your domain, you just have to respond to questions. Theory will automatically defend itself in due course.

Mainstream cosmology on the whole, does not need defending. It has already run the gauntlet and passed peer review.
What is being attacked and derided, is obviously agenda driven questions on problem areas, that you claim invalidate all of cosmology.
Let's get it straight...The BB/Inflationary model of universal/spacetime evolution is not going to be rescinded any time soon.
Cosmological expansion is observed, and "tired light"as an alternative, has been invalidated long ago.
Observational evidence shows DE exists. As yet we have no actual data that tells us what it is.
Observational evidence shows that DM exists. As with DE, as yet we are not sure what it actually is.
SR/GR/the BB all support and validate each other, and each within there own particular realm, are at the top echalon of certainty for scientific theories.

 

[RajeshTrivedi]

...The BB/Inflationary model of universal/spacetime evolution is not going to be rescinded any time soon.

Again slipped. You have developed this severe tendency of foot in mouth syndrome..Take some rest, cosmology and its prevalent theories will stay put even without your defense and of course even with as you mistakenly call agenda driven questions.

 

[origin]

And note that in gravitational redshift, the photon doesn't actually lose any energy.

What do you mean that a gravitational redshifted photon doesn't actually lose energy? Do you think that a photon that has a gravitational blue shift doesn't actually gain energy? How about an asteriod that starts out at a speed of 0 mph relative to the earth and then is accelerated by the earths gravity to 25,0000 mph by the time it reaches the earth. Has the asteriod not actually gained any energy?

 

[origin]

You guys are working on incorrect premises that you have to defend it, That is not expected of you and neither it falls in your domain, you just have to respond to questions.

?? We are responding to your questions, explaining to you what the theories say, it is not a matter of defending the theory, it is simply a matter of trying to help you to understand the theory. When you work so hard not to understand what we are saying, you shouldn't be surprised to see some frustration on our part.

 

[wellwisher]

We can prove, in the lab, that high mass density, expanding into lower mass density, will cause local space-time to expand; explosion. This scenario has matter leading the expansion of space-time. How do you prove, in the lab, that space-time can expand first and carry mass along with it; distance between galaxies, like the current consensus theory? The answer is dark energy.

The problem is, dark energy has not been seen in the lab, so there is no provable energy source, other than the premise of a self looping theory? Isn't the concept of dark energy, conceptually no different from Big Foot, in that we can see what appears to be the impact of Big Foot's feet in the snow, but we never see him close up to verify he is real. The concept of dark energy is using the same 2nd degree proof approach used for Big Foot and Aliens; inferred by the imagination from apparent affect, but without direct lab proof. I understand the appeal of mythology and how this can be a good sales tool, but what about lab proof to avoid the Big Foot science approach?

If we put mass, leading the movement of space-time, like we can proof in the lab, we can infer that the blue shift between galaxies is due to increasing mass density due to the impact of gravity. There is no need for Big Foot style inference. If we assume energy conservation, the apparent gain of energy implicit of the blue shift, should be equal to the apparent energy loss; red shift elsewhere. Maybe this is what is called dark energy but it is not that dark you assume mass leads space-time like in GR.

 

[Dr_Toad]

That made no sense whatsoever. Is the sun over the yard-arm in your time zone?

 

[origin]

We can prove, in the lab, that high mass density, expanding into lower mass density, will cause local space-time to expand; explosion. This scenario has matter leading the expansion of space-time.

False. Changing the density of matter does not cause space-time to expand.

How do you prove, in the lab, that space-time can expand first and carry mass along with it; distance between galaxies, like the current consensus theory? The answer is dark energy.

False. Dark energy is not the driver of expansion.

The problem is, dark energy has not been seen in the lab, so there is no provable energy source, other than the premise of a self looping theory? Isn't the concept of dark energy, conceptually no different from Big Foot, in that we can see what appears to be the impact of Big Foot's feet in the snow, but we never see him close up to verify he is real. The concept of dark energy is using the same 2nd degree proof approach used for Big Foot and Aliens; inferred by the imagination from apparent affect, but without direct lab proof. I understand the appeal of mythology and how this can be a good sales tool, but what about lab proof to avoid the Big Foot science approach?

If we put mass, leading the movement of space-time, like we can proof in the lab, we can infer that the blue shift between galaxies is due to increasing mass density due to the impact of gravity. There is no need for Big Foot style inference. If we assume energy conservation, the apparent gain of energy implicit of the blue shift, should be equal to the apparent energy loss; red shift elsewhere. Maybe this is what is called dark energy but it is not that dark you assume mass leads space-time like in GR.

The rest is the typical poorly thought out anti-science rant of someone who has no science education.

 

[PhysBang]

Spacetime doesn't expand, space expands.

Can you please show us your theory where there is space expanding and no spacetime? Because if you cannot show us how your theory can get measurement evidence, then we will have to reject it in favor of physics theories.

And note that in gravitational redshift, the photon doesn't actually lose any energy.

Please take any cosmology textbook you would like and discuss the error they make when they discuss energy loss due to redshift.

 

[Walter L. Wagner]

Please take any cosmology textbook you would like and discuss the error they make when they discuss energy loss due to redshift.

For that matter, take any introductory physics text, and show the error. I believe he mis-spoke. Happens a lot around here. Red shift is always a lengthening of wave-length (with concomitant lowering of frequency to keep the speed at c), with a lower energy for the resultant photon.