Dark Energy

[metastable]

I have a question having to do with black holes, astrophysical jets, redshift, gravitational redshift, the relativistic aberration, the visible universe and dark energy...

My understanding of the relativistic aberration is objects moving near the speed of light exhibit the searchlight effect to stationary observers, where the trajectory of uniformly emitted photons in the rest frame of the relativistic emitter appear bent towards the moving object's direction of motion to the stationary observer. This can be seen in some relativistic jets because the "receding" jet may appear invisible due to the searchlight effect.

So my question has to do with what % of photons emitted uniformly in all directions in the rest frame of an object which is moving very near the speed of light directly away from very near a black hole will be gravitationally redshifted? If two spaceships were moving towards each other, but both were moving very nearly the speed of light away from a massive black hole, could they observe their transmissions to be redshifted?

In other words how do we prove that the visible universe isn't part of a relativistic jet moving nearly the speed of light away from an unfathomably large black hole which is within the universe, but outside the observable universe, but still "close" and large enough to cause the observed redshift proportional with distance? How would growth in mass of such a black hole over time affect the observed redshift over time?

[notFritzArgelander]

The emitted photons are 100% redshifted as determined by the point of origin.

Your model has problems in that the homogeneity and isotropy of the cosmic microwave background refutes it.

[metastable]

[mention]notFritzArgelander[/mention] thank you for your response. I had based the conjecture on trying to estimate what % of photons emitted uniformly in all directions in the rest frame of the emitter would be gravitationally redshifted based on the initial velocity away from the black hole and the relativistic aberration formula. Unless I made a mistake my findings were:

Initial V=299792457.6086310810085m/s

A = cos(motion path angle relative to the vector from the observer to the source at the time when the light is emitted)
B = 299792457.6086310810085
C = C = 299792458m/s
D = cos(angle observed to source) = 0 = cos(90deg)

A = -1 * ( ( ( -1 * B ) - ( D * C ) ) / ( C + ( D * B ) ) )

A = -1 * ((( -1 * 299792457.6086310810085 ) -( 0 * 299792458 ) )/ ( 299792458+( 0 * 299792457.6086310810085)))

A = 0.9999999986945338064792 = cos(0.00292766)

0 degrees + 0.00292766 degrees = 0.00292766 degrees blueshifted towards black hole

180 degrees - 0.00292766 degrees = 179.99707234 degrees redshifted away from black hole

0.00292766 / 180 = 0.00162647% of photons gravitationally blueshifted when initial V = 299792457.6086310810085m/s

100-0.00162647= 99.99837353% of photons gravitationally redshifted when initial V = 299792457.6086310810085m/s

[mention]notFritzArgelander[/mention] So in your view no initial velocity and size of black hole could result in observed redshifts that approach homogeneity and isotropy?

[notFritzArgelander]

@notFritzArgelander thank you for your response. I had based the conjecture on trying to estimate what % of photons emitted uniformly in all directions in the rest frame of the emitter would be gravitationally redshifted based on the initial velocity away from the black hole and the relativistic aberration formula. Unless I made a mistake my findings were:

I'm not going to go into the weeds with your calculations. One should never begin a calculation without knowing the answer beforehand. You risk playing three card monte with yourself and creating self deception.

@notFritzArgelander So in your view no initial velocity and size of black hole could result in observed redshifts that approach homogeneity and isotropy?

I would make a stronger statement. It is not just my view. It is a matter of physics that your scenario is falsified by CMB homogeneity and isotropy. No "my view" about it.

A jet is limited in size in two spatial directions and has a highly preferred direction in the third. Such symmetry considerations imply that homogeneity and isotropy are impossible. No calculation is needed to confuse a very simple issue.

[notFritzArgelander]

Let me add a quote by the great theoretical physicist J A Wheeler: https://www.goodreads.com/quotes/988735 ... nswer-make

“Never make a calculation until you know the answer. Make an estimate before every calculation, try a simple physical argument (symmetry! invariance! conservation!) before every derivation, guess the answer to every paradox and puzzle. Courage: No one else needs to know what the guess is. Therefore make it quickly, by instinct. A right guess reinforces this instinct. A wrong guess brings the refreshment of surprise. In either case life as a spacetime expert, however long, is more fun!”

Before I read this I knew it was true. I remember my first advanced physics course's 1st midterm. It was classical mechanics. The problem was that two folks (different masses) were standing back to back on a plank (mass given, uniform density) on perfectly frictionless ice. They began a complicated kabuki dance described by equations that were given. The requested result was "how much did the center of mass move after the dance finished".

Many folks did furious calculations. They were marked wrong. There were different degrees of wrongness depending on how well they calculated.

I simply noted: "There are no external forces on the system therefore the center of mass does not move from its initial position." Alone, I got full credit.

[metastable]

The assumptions for my scenario was that the width of the jet would be greater than the width of the visible universe—a jet of sufficient in size that all visible matter would be composed of jet material, the black hole would be of similar size to the observable universe or larger, the velocity of the jet sufficient that the relativistic aberration would cause all but a tiny fraction of uniformly directed photons emitted from within the jet to travel away from the black hole, and our distance from the event horizon at of at least one event horizon radius.

[notFritzArgelander]

The assumptions for my scenario was that the width of the jet would be greater than the width of the visible universe—a jet of sufficient in size that all visible matter would be composed of jet material, the black hole would be of similar size to the observable universe or larger, the velocity of the jet sufficient that the relativistic aberration would cause all but a tiny fraction of uniformly directed photons emitted from within the jet to travel away from the black hole, and our distance from the event horizon at of at least one event horizon radius.

1) That all still leaves a preferred direction (of the flow of the jet) to break symmetry.
2) If you are building in by hand dimensions of size to make your model untestable by observation then it's not a good model. I objected to MOND because it was an example of "hiding" from observations. It simply is not the scientifically honest thing to do and should not be entertained.
3) What observation is predicted by your model that the standard cosmology DOESN'T predict?
4) If you have no new prediction that shows a difference from the standard cosmology, then Ockham's bright and shiny razor prefers the standard cosmology.

[notFritzArgelander]

Furthermore, in a thread entitled dark energy, the proposed model does nothing to explain dark energy. It would only explain an expansion without acceleration. The expansion would be in only two dimensions (the cross section of the proposed jet) and there would be no expansion in the third spatial direction, the direction of the jet.

[metastable]

I thought if the jet were fast enough under such circumstances, it would appear to those within it that objects become more redshifted with increasing distance, because although those observers comoving with the jet might believe they were shining a light back towards the black hole, due to their velocity and the relativistic aberration almost all of those photons would actually be traveling away from the black hole. To answer your question the observation predicted by the model is redshift proportional with distance between 2 observers, along with a mechanism (gravitational redshift).

I’m saying under such circumstances, even if 2 objects weren’t moving away from each other, they might mistake the gravitational redshift for doppler redshift, and assume the distance between them was increasing.

[notFritzArgelander]

I thought if the jet were fast enough under such circumstances, it would appear to those within it that objects become more redshifted with increasing distance, because although those observers comoving with the jet might believe they were shining a light back towards the black hole, due to their velocity and the relativistic aberration almost all of those photons would actually be traveling away from the black hole. To answer your question the observation predicted by the model is redshift proportional with distance between 2 observers, along with a mechanism (gravitational redshift).

I’m saying under such circumstances, even if 2 objects weren’t moving away from each other, they might mistake the gravitational redshift for doppler redshift, and assume the distance between them was increasing.

It's too complicated. Very much in this style: https://en.wikipedia.org/wiki/Rube_Goldberg

It cannot deal with the symmetry issues I've raised. Nor does it provide a mechanism for the observed expansion appearing to accelerate.

[metastable]

As for the accelerating expansion, I mentioned in my first post “How would growth in mass of such a black hole over time affect the observed redshift over time?”

As for the symmetry, my understanding is the closer the velocity of the jet is to the speed of light, the more symmetrical the effects would become. I mean that due to the relativistic aberration, as the velocity approaches light, the angle of all emitted photons emitted by the jet approaches the angle of motion of the jet to a hovering observer. Within the jet, my understanding is the closer to the speed of light the velocity of the jet was with respect to the black hole, the more uniformly objects from different directions would appear redshifted with respect to distance from the observer (whether above, below or to the side with respect to the hole), it is conjectured.

[notFritzArgelander]

As for the accelerating expansion, I mentioned in my first post “How would growth in mass of such a black hole over time affect the observed redshift over time?”

It wouldn’t. You’ve located this object outside the observable universe so its effects are unobservable.

As for the symmetry, my understanding is the closer the velocity of the jet is to the speed of light, the more symmetrical the effects would become. I mean that due to the relativistic aberration, as the velocity approaches light, the angle of all emitted photons emitted by the jet approaches the angle of motion of the jet to a hovering observer. Within the jet, my understanding is the closer to the speed of light the velocity of the jet was with respect to the black hole, the more uniformly objects from different directions would appear redshifted with respect to distance from the observer (whether above, below or to the side with respect to the hole), it is conjectured.

This is just wrong. In a jet there’s a preferred direction. No further confused word salad is required.

[notFritzArgelander]

Furthermore in such a model the conditions of Noether’s Theorem don’t hold globally. So conservation of energy, momentum and angular momentum don’t hold either.

[metastable]

For reference, such jets on a smaller scale than proposed are obervable:

https://www.cv.nrao.edu/course/astr534/ ... actic.html

[notFritzArgelander]

For reference, such jets on a smaller scale than proposed are obervable:

EA1FF843-6B23-47AC-B532-496BD65F1ABC.jpeg

https://www.cv.nrao.edu/course/astr534/ ... actic.html

Yes. So what? This is, of course, completely irrelevant to the point: there is nothing in your proposal that isn't covered or predicted better by the standard model of cosmology. All the machinery of your idea is UNOBSERVABLE.

Your idea is:
1) falsified by SN data on the acceleration of Hubble expansion (it would predict zero acceleration)
2) falsified by CMB data on the homogeneity and isotropy the universe
3) is likely falsified by not accounting for Gig Bang nucleosynthesis
4) is falsified by having cylindrical rather than spherical symmetry
5) because it has a broken global symmetry Noether's Theorem is violated so energy, momentum, and angular momentum conservation cannot hold.

So there are five (at a minimum) fatal flaws to your idea. I don't want to bother to look for more.

[metastable]

I was reading this article entitled “4 Anomalies in the Big Bang Afterglow”...

https://futurism.com/4-anomalies-in-the ... -afterglow

...when I stumbled across this passage about the “cold spot” in the data....

...any comments would be greatly appreciated.

[notFritzArgelander]

It is unlikely, not impossible, that it's merely a statistical fluctuation.

The overly hyped alternatives in the Futurism article are much less likely for various reasons.

https://en.m.wikipedia.org/wiki/CMB_cold_spot

[notFritzArgelander]

It is unlikely, not impossible, that it's merely a statistical fluctuation.

The overly hyped alternatives in the Futurism article are much less likely for various reasons.

https://en.m.wikipedia.org/wiki/CMB_cold_spot

I'll expand a bit with a personal take.

The Futurism article rightly labels the alternatives of 1) interaction with a different universe and 2) a universe in mass black hole as "fringe hypotheses" and rightly so. Where I fault the article is that it labels these ideas as fringe but doesn't say why. Thus it hypes fringe ideas by giving them exposure but not providing corrective criticism. I'll undertake that here.

1) The cold spot as interaction with a different universe

This hypothesis is simply self contradictory in several ways. Multiple universes are invoked by a small group of string theory cosmologists as a solution to the fine tuning problem in cosmology: why are the laws of physics and the physical constants as they are? It postulates simultaneously existing spatially separated universes in which laws of physics and values of physical constants take on different values. There are two logical flaws in invoking multiverses as a cause of the cold spot and one killer physical flaw.

• The observable universe consists of all measurable phenomena, therefore https://www.youtube.com/watch?v=sqcLjcSloXs

• Since the laws of physics vary from multiverse to multiverse it is impossible to predict what effect one would have on another. Heat? Cool? Nothing?

• Since spatially coexistent multiverses have different physical laws the conditions for Noether's theorem do not hold and conservation laws for energy, momentum, and angular momentum conservation do not hold. This is contrary to experience.

2) The cold spot is a universe mass black hole

Current observations (Planck mission) indicate the universe is flat with an average energy density of zero accounting for gravitating normal and dark matter, radiation, and dark energy. So the volume of the universe is infinitely large and the density is infinitesimally small and the total mass is undefined.

The proponents of this idea (AFAIK) have also done no calculations to show this is possible for even a very large mass object.

So an improbable void, which is only mildly improbable, is still a heckuva lot more probable than these unsupported frogmen ideas!

[notFritzArgelander]

.....
So an improbable void, which is only mildly improbable, is still a heckuva lot more probable than these unsupported frogmen ideas!

Is an autocorrect induced typo. It should have read:

So an improbable void, which is only mildly improbable, is still a heckuva lot more probable than these unsupported fringe ideas!

[metastable]

This 2017 paper presents significant evidence the CMB cold spot isn’t caused by a void

https://arxiv.org/pdf/1704.03814.pdf