QM + GR = black holes cannot exist

Bingo!

 

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I'm afraid that's wrong. A gravitational field alters the motion of light and matter through space. A black hole doesn't suck space in or grow fat on vacuum energy. We do not live in some Chicken-Little world where the sky is falling in. Have a look at this essay where Einstein is talking about field theory. See this paragraph:

Note how a gravitational field is "a state of space". That state is not falling inward like it's vanishing down some plughole. It's an inhomogeneous state, modelled as curved spacetime. See this paper, and Einstein's 1920 Leyden Address:

 

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Gravitational potential determines time dilation. This isn't an illusion, it's a fact. Your analogy is OK but one would 'imagine' the fish continuing to swim at their normal pace, fighting against the current; if they were wearing watches you might be thinking that their watches are not slowing down in any manner. This fails because it's actually the rate of time passing which slows down, not the apparent net distance swam. If you acknowledge that GPS must make gravitational time dilation corrections then you must also acknowledge that mass literally slows down time relative to observers distant to it. Farsight is also mistaken on this point.

 

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I'm sorry paddoboy, but that's cargo-cult nonsense from the sort of people who would tell you in all seriousness that the universe is quite literally made of mathematics. You know that space isn't falling past you into the floor. You know it's nonsense.

 

Cargo-cult popscience trash. Don't you know another tune? This one is boring.

 

It's an analogy. The same as the rubber sheet and bowling ball....or the raisin loaf.
Gravity is a state of space certainly, actually a state of spacetime curvature, which you appeared to be pedantically arguing against earlier.
Any curvature of spacetime of course can easily be Imagined to be "pulling in" the spacetime, as per the heavy bowling ball on a rubber sheet.


The following may help in visualising what actually happens....
http://casa.colorado.edu/~ajsh/home.html

 

Even more nonsensical in actual fact, could be the case of the three or four Alternative hypothesis pushers on this forum, all claiming to have a ToE, but completely fail the scientific method and peer review.
Again my view aligns with accepted mainstream models, so I let your claims of cargo cult nonsense, and where it lays, speak for itself.

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Time dilation depends on ones FoR.
From the fish's frame of Reference, time passes as per normal.

 

We're all familiar with that picture, and I've said that you can plot something like that using light clocks in an equatorial slice through the Earth and the surrounding space:

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But it isn't a "pulling in". Note the energy-pressure diagonal in the stress-energy tensor. It's a "pushing out". And to imagine it you have to try to forget about the curvature of the Earth. You zoom in, like this:

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Imagine each cell has a volume, and the volume varies in line with the Ricci curvature tensor. Because space is inhomogeneous, the coordinate speed of light varies and light curves, and we model it as curved spacetime.

There's a lot in there. Can you be more specific?

You believe in cargo-cult nonsense that totally contradicts general relativity, and you are kidding yourself that it's mainstream.

How so? I've never said anything untoward about gravitational time dilation.

 

It was interesting looking at that site. I found this on http://jila.colorado.edu/~ajsh/insidebh/waterfall.html

"The picture of spacing falling into a black hole has a sound mathematical basis, first discovered in 1921 by the Nobel prize-winner Alvar Gullstrand2, and independently by the French mathematician and politician Paul Painlevé3, who was Prime Minister of France in 1917 and then again in 1925.
It is not necessary to understand the mathematics, but I do want to emphasize that, because the concept of space falling into a black hole is mathematically correct4, inferences drawn from that concept are correct.

The Gullstrand-Painlevé metric is

\(ds^2=−d{t^2}_{ff}+(dr−vdt_{ff})^2+r^2(dθ^2+sin^2θdϕ^2)\)
which is just the Schwarzschild metric expressed in a different coordinate system. The free-fall time tff is the proper time experienced by observers who free-fall radially from zero velocity at infinity. The velocity v in the Gullstrand-Painlevé metric equals the Newtonian escape velocity from a spherical mass M
\(v=−2 \sqrt{\frac{GM}{r}}\)
with a minus sign because space is falling inward, to smaller radius.
Physically, the Gullstrand-Painlevé metric describes space falling into the Schwarzschild black hole at the Newtonian escape velocity. Outside the horizon, the infall velocity is less than the speed of light. At the horizon, the velocity equals the speed of light. And inside the horizon, the velocity exceeds the speed of light. Technically, the Gullstrand-Painlevé metric encodes not only a metric, but also a complete orthonormal tetrad, a set of four locally inertial axes at each point of the spacetime. The Gullstrand-Painlevé tetrad free-falls through the coordinates at the Newtonian escape velocity.

It is an interesting historical fact that the mathematics of black holes was understood long before the physics. Einstein himself misunderstood how black holes work. He thought that the Schwarzschild geometry had a singularity at its horizon, and that the regions inside and outside the horizon constituted two separate spacetimes. I think that even today research into general relativity is too often dominated by abstract mathematical thinking at the expense of conceptual understanding."

 

Coming from someone who has claimed he has a ToE, and vilifies the scientific method and peer review, I find that remark rather amusing.

 

except there is ,at this moment, 23 pages showing you " real physics " which you are continuing to ignore.

 

I thought you were mistaken when you said...

...because I followed that up with the fact that the light does slow down as the mass and its density increases...but that's only true from a distant source. As I copied your quote I noticed that you restricted this observation to the person holding the laser pointer. My bad!

 

Only it doesn't. It just doesn't. The space in the room you're in is not falling down.

I think he was right about that. Nowadays people tend to say it's a mere artefact, but I think it's something very real.

I'm not sure if you said that, but it's true.

Not so your bad. You perhaps missed something here. It's rather counterintuitive, but it's crucial. You know gravitational time dilation reduces as you ascend? You know how Einstein said a curvature of rays of light can only occur when the speed of light varies with position? You know how an optical clock goes faster if you raise it up? That optical clock goes faster because the coordinate speed of light increases. Because light goes faster. And as the ascending photon goes up, it doesn't slow down. It goes faster and faster. That's the nub of Einstein's GR that you never ever hear about.

Time for bed.

 

Yes, the distant observer would say that the speed of light increases as it ascends. I agree with you. This is the same thing as saying the speed of light decreases as it descends, agreed? But when you said

I was answering. It's because at that point where the black hole comes into existence coordinate time and the speed of light have stopped.

 

Note how Farsight has quotation marks around "a state of space", but the original does not contain that phrase. Indeed, in the very passage that Farsight quotes, Einstein refers to gravity as "structural properties of the space - time continuum", a direct contradiction to Farsight's claim that, according to Einstein, gravity is a property of space, not spacetime.

 

The Schwarzschild geometry has a coordinate singularity at r=2M. Einstein would have to be as clueless as you not to understand Schwarzschilds solution. The rain coordinates don't predict space is falling into the black hole. You're living proof that conceptual understanding can be misinformed nonsense when you don't understand what you're talking about.

 

Nice pickup.
Hmmm, not only misinterpretations, phrases out of context, but now claiming quotes attributed to people that weren't.
Not that I see much difference between space and spacetime, although I prefer the latter.

You having been telling us all what you agree and disagree with for ages...You have also told us you have a ToE.....
That does not make either claim as factual or true.

 

The point to remember is that it is a useful analogy. Spacetime is not a river nor is light a fish. Spacetime is not a rubber sheet or a raisin loaf either, but each are analogous as to how gravity, light and BH's appear to operate.
The only thing we can be sure of, is that space exists, time exists, and as a consequence, spacetime exists.

 

Hi, Farsight. Here's Prof. Moore's reply to your thought experiment: