Does this explain what generates gravity?

Gravity ?

You can make studies : long way
You can ask Brad Pitt : can be long too
You can ask GPT : can be... (ask GPT)

If Gravity is a question time related and vis versa then you are in " de salles draps" ! (aka beginning of where is your Knewton spot to have a reference point to move the universe with your lever, sorta).
 
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Circular reasoning:
Since no one has observed a black hole, it does not make sense to create graphs based on arbitrarily interpreted and labeled observations;-)-;
 

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Since no one has observed a black hole
One problem is that the nearest one can't be imaged due to dust and gas clouds. Radio can do something but in some ways isn't as informative as optical including IR.
Oddly a well known "reliable" news outfit gives info on how event horizon imaged it
https://www.foxweather.com/earth-sp...e-black-hole-at-center-of-our-galaxy-revealed
Processing loads of images even with a weighting

They are also good for the media but fact is many images that are around are artists impressions. It's easy to find paintings by Picasso of human faces that don't look much like the real thing. Black hole ones are based on theory only. Those theories can only be checked via observation and that is a bit tricky in a number of areas.

Photons are a bit bizarre from
https://www.wtamu.edu/~cbaird/sq/2015/01/12/why-is-light-pure-energy/
Momentum – This is a motional property that describes light's ability to collide with other objects and get them moving.
Kinetic Energy – This is the energy of the light due to its motion. Note that because a photon has no mass, its kinetic energy equals its total energy. The energy of light allows it to create a gravitational field according to General Relativity
For instance, the energy E of a photon equals its frequency f times a constant, E = hf. Similarly, the momentum p of a photon equals its wavevector k times a constant, p = ℏk


One of the arguments against red shift tired light ideas is absorption lines. LOL I've wondered why these can't move as well. They show in frequency spectrums positions know when they aren't produced far away. Something else can shift them,
Spectral lines can also be redshifted due to the influence of strong gravitational fieldsthis is not surprisingly known as gravitational redshift.

Tired light gets mentioned now again even if when dismissed eg
https://www.sciencetimes.com/articl...y-being-twice-as-old-as-initially-thought.htm

Big Bang figures as well against it.
 
cumbb, I wonder what Planet you live on sometimes!

View attachment 1193577

https://en.wikipedia.org/wiki/Sagittarius_A*

I think you are wrong and Einstein was right.. consider it a grow-up moment. :)
Kids planet, it seems;-)

Circular reasoning:
"... arbitrarily interpreted and labeled observations"-)-;

... especially since again it is not mentioned, under which circumstances, how elaborate also in image processing, thus also in flowing in previous interpretation, up to arbitrary design and also fraud. It is about "money", not about "science"!
 
Again from the Solar Orbiter, the highest resolution image of the Sun’s full disc and outer atmosphere, the corona, ever taken (see attachment).

An image of the Earth is included for scale, at the two o'clock position.
 

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;-)
I remember:
"Our equations for the sun, for example, as a ball of hydrogen gas, describe a sun without sunspots, without the rice-grain structure of the surface, without prominences, without coronas. Yet, all of these are really in the equations; we just haven't found the way to get them out."
https://www.goodreads.com/quotes/6879068-we-have-written-the-equations-of-water-flow-from-experiment
https://books.google.de/books?id=4r...without prominences, without coronas.&f=false

Suns are Anodes. Like in tubes it glows;-)
 
A spinning supermassive black hole was discovered in 2014, after it tore apart a star that strayed too close, causing a flash of bright light that was spotted by a system of optical telescopes.

That black hole’s event horizon is about 300 times bigger than the Earth.

It was clocked to be spinning at 50% of the speed of light.

The few supermassive black holes whose rotation rates have been clocked to date have been found to whip around between 33% of the speed of light and the theoretical upper limit of 84%.
 
You might ask, "How is the spin of a black hole measured?".

A consequence of Einstein's theory of relativity is that the faster a black hole spins, the closer its accretion disk can lie to it.

Scientists assess how close the inner edge of an accretion disk comes to a black hole by analysing the X-ray radiation coming from the black hole.

Because this distance depends on the black hole's spin, the spin rate can then be determined.

1689528738047.png


The mathematics may be complex, but the necessary observations have been made by NASA's Nuclear Spectroscopic Telescope Array (NuSTAR), together with the European Space Agency's XMM-Newton telescope.
 
Quick interrupt, how fast does a black hole spin?

With the greatest respect, that is, and there is no nice way to say this, a dumb question!

You have not specified any particular Black Hole. Therefore the Kerr Metric is unknown.

My honest view is the Answer lies within the Question. Once you ask an honest question, the answer lies within it.

Most folks in this life are incredibly lazy. They want quick answers without doing any WORK!

I always recommend a bit of reading to such immature people:

The Curious Incident of the Dog in the Night-Time.jpg

https://en.wikipedia.org/wiki/The_Curious_Incident_of_the_Dog_in_the_Night-Time

After that, Einsteinian Physics is easy enough. But you will argue! There, I have said it. :(
 
I always recommend a bit of reading to such immature people...

Does anyone else get the impression that Steve could do with a bit of reading of his own! ;)

1689545527825.png


The Kerr metric he mentions is an equation for a spinning, spherical mass that includes its spin or, more precisely, its angular momentum per unit mass.

You can find the mathematics here: https://medium.com/quantaphy/the-ke...ativity-and-rotating-black-holes-89b1a6e977fa

A simplified model of a Kerr black hole includes a ring singularity, an event horizon and an ergoregion - a region located outside its event horizon.

1689547092906.png


Spacetime in the ergoregion is being pulled around by the rotating black hole and so participates in its rotation - an effect known as frame dragging.

Learning all the time! :D
 
Apologies, I was getting frustrated by the endless random comments, which don't seem to be solving anything and are making this thread hard to follow.

If I have done the rough calculation for this Black Hole correctly:

https://en.wikipedia.org/wiki/GRS_1915+105

It's 18 solar masses, about 40km shwarzschild radius (if that applies to a Kerr Black Hole) and rotates 1150 times per second.

The accretion disk rotates in the same direction as the Black Hole pulled along by frame-dragging.

I haven't done the exact sums, but I would guess this rotation is close to the speed of light, as with Galu's example. Which is a bit mind-boggling.

This is all preposterous Physics. But seems to be how it is.
 
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To understand "theories", to be critical of "theories", one has to look into the history of "theories", into the biographies of their "theorists"!
Not truths but methods are discussed in "science"!

Clearer: Since the RT is based on the equation of two obviously different phenomena, it is nonsense, unscientific: At the beginning there is e.g. the "equivalence principle", where the "observer" is put into two boxes. This is deception (like "Hubble Law" - e.g. prohibit of discuss), forcing subjective observation and interpretation (unscience principle) instead of objective observation and interpretation (science principle). Result is non-science and sloppiness only -
see #1048: Coriolis effect = Gravity!

ALL the "physical conclusions" that follow from this are therefore unscientific. Including mathematics (arbitrary constants, reification of "time" - starts 1909 by mathematical gimmick by Herman Minkowsky -, "space"....).
More precisely: for the observer and interpreter in the game box (is after all one only - "equivalent") there may be black holes, dark matter, dark energy, wormholes, parallel universes, strings.... may exist mental, NOT physical. But just in the game box only;-)-;
Further: Conclusions on the "world out there" should not make the observer in the box at all, because this cannot exist for him.
Or also: Or if "world outsinde" is known by him: conclusions made in the box must not be transferred to a "world outside".
And so on;-)-;

Restricted admission of observation is THE condition for Einstein's RT. But with that they are UN-scientific!