Daryl Janzen
@darylj.bsky.social
physicist/cosmologist trying to understand what reality is. don’t understand fragile egos: valid correction is a gift.
cosmiCave.org
cosmiCave.org
From a pure experimental/observational standpoint I don’t think there’s a significant enough difference to be detected. The consequences matter more for theory, and the issue of basing subsequent models on false premises.
November 16, 2025 at 5:56 PM
From a pure experimental/observational standpoint I don’t think there’s a significant enough difference to be detected. The consequences matter more for theory, and the issue of basing subsequent models on false premises.
Yep! My suspicion is that the “essentially frozen” still-collapsing ball is so close to a true, vacuous Kerr BH, observationally, that the idealized situation is insignificantly different from the actual one. It’s an important ontological correction, and misconceptions lead to more downstream. But..
November 16, 2025 at 5:54 PM
Yep! My suspicion is that the “essentially frozen” still-collapsing ball is so close to a true, vacuous Kerr BH, observationally, that the idealized situation is insignificantly different from the actual one. It’s an important ontological correction, and misconceptions lead to more downstream. But..
To answer your question directly: the models DO assume a formed event horizon. I’m not aware of any observable differences in the physics of pre-horizon balls coalescing. I don’t think anyone has worked through it because everyone falsely thinks the colliding BHs have formed horizons/singularities.
November 16, 2025 at 5:17 PM
To answer your question directly: the models DO assume a formed event horizon. I’m not aware of any observable differences in the physics of pre-horizon balls coalescing. I don’t think anyone has worked through it because everyone falsely thinks the colliding BHs have formed horizons/singularities.
The prior assumption in the models that they are already completed is at best a simplifying approximation of the ultra-compact, pre-horizon Kerr-like balls in our past light cone that actually collided. At worst it’s a ubiquitous misunderstanding among BH/GW physicists.
November 16, 2025 at 5:10 PM
The prior assumption in the models that they are already completed is at best a simplifying approximation of the ultra-compact, pre-horizon Kerr-like balls in our past light cone that actually collided. At worst it’s a ubiquitous misunderstanding among BH/GW physicists.
The image of Sgr A* and the GWs we observe from mergers, all carry information from a local time at the BH(s) prior to collapsing matter finally reaching the horizon.
November 16, 2025 at 5:06 PM
The image of Sgr A* and the GWs we observe from mergers, all carry information from a local time at the BH(s) prior to collapsing matter finally reaching the horizon.
It’s the only valid logical conclusion because of causality. Straight from the light cone structure in the geometry. The very definition of “event horizon” is that that event happens _after_ everything all external observers can ever see. That includes observed mergers.
November 16, 2025 at 5:05 PM
It’s the only valid logical conclusion because of causality. Straight from the light cone structure in the geometry. The very definition of “event horizon” is that that event happens _after_ everything all external observers can ever see. That includes observed mergers.
It then follows with BBH mergers and GWs that the models assume already completed BHs at the time they coalesce. But that’s actually straight up invalid. By straightforward logical proof (my pinned thread) the two BHs MUST have been actually pre-horizon at the time of collision.
November 16, 2025 at 5:01 PM
It then follows with BBH mergers and GWs that the models assume already completed BHs at the time they coalesce. But that’s actually straight up invalid. By straightforward logical proof (my pinned thread) the two BHs MUST have been actually pre-horizon at the time of collision.
The idea physicists tend to carry in their heads is linked to fig b. E.g. see the Penrose quote in my essay. Essentially, the BH actually forms “out there”, but we are left with a kind of ghost image of the collapsing object “before” the BH formed.
November 16, 2025 at 4:57 PM
The idea physicists tend to carry in their heads is linked to fig b. E.g. see the Penrose quote in my essay. Essentially, the BH actually forms “out there”, but we are left with a kind of ghost image of the collapsing object “before” the BH formed.
None of these follow from GR.
They follow from reading (b) incorrectly.
More detail here — happy to explain anything:
cosmicave.org/2025/11/06/w... (13/13)
They follow from reading (b) incorrectly.
More detail here — happy to explain anything:
cosmicave.org/2025/11/06/w... (13/13)
What if black holes never actually form?
For the better part of a century, physicists have treated the inevitable collapse of stars as proof that black holes already exist. But inevitability is not actuality—and confusing the two has prod…
cosmicave.org
November 13, 2025 at 10:15 PM
None of these follow from GR.
They follow from reading (b) incorrectly.
More detail here — happy to explain anything:
cosmicave.org/2025/11/06/w... (13/13)
They follow from reading (b) incorrectly.
More detail here — happy to explain anything:
cosmicave.org/2025/11/06/w... (13/13)
• Hawking radiation from already-formed horizons
• information-loss paradoxes
• naked singularities
• cosmic censorship
…all while the collapsing star is still collapsing in the external universe’s (eg our) causal past.
(12/)
• information-loss paradoxes
• naked singularities
• cosmic censorship
…all while the collapsing star is still collapsing in the external universe’s (eg our) causal past.
(12/)
November 13, 2025 at 10:11 PM
• Hawking radiation from already-formed horizons
• information-loss paradoxes
• naked singularities
• cosmic censorship
…all while the collapsing star is still collapsing in the external universe’s (eg our) causal past.
(12/)
• information-loss paradoxes
• naked singularities
• cosmic censorship
…all while the collapsing star is still collapsing in the external universe’s (eg our) causal past.
(12/)
Formally, this picture is equally valid — and avoids all the paradoxes. The traditional reading (b) creates the illusion of:
• “real” completed black holes hiding offstage
• already-formed horizons and singularities
• mergers of singularities
(11/)
• “real” completed black holes hiding offstage
• already-formed horizons and singularities
• mergers of singularities
(11/)
November 13, 2025 at 10:10 PM
Formally, this picture is equally valid — and avoids all the paradoxes. The traditional reading (b) creates the illusion of:
• “real” completed black holes hiding offstage
• already-formed horizons and singularities
• mergers of singularities
(11/)
• “real” completed black holes hiding offstage
• already-formed horizons and singularities
• mergers of singularities
(11/)
GR also allows (c), where:
• the star is still collapsing toward its horizon
• the horizon is reached only at the end of time
• the singularity never actually forms
• the image we see is from earlier, but ontologically the object is still collapsing “out there”
(10/)
• the star is still collapsing toward its horizon
• the horizon is reached only at the end of time
• the singularity never actually forms
• the image we see is from earlier, but ontologically the object is still collapsing “out there”
(10/)
November 13, 2025 at 10:10 PM
GR also allows (c), where:
• the star is still collapsing toward its horizon
• the horizon is reached only at the end of time
• the singularity never actually forms
• the image we see is from earlier, but ontologically the object is still collapsing “out there”
(10/)
• the star is still collapsing toward its horizon
• the horizon is reached only at the end of time
• the singularity never actually forms
• the image we see is from earlier, but ontologically the object is still collapsing “out there”
(10/)
Picture (b) implicitly assumes:
• the star already reached its horizon
• the horizon already exists “now”
• the singularity already formed
• the image we see is just a delayed ghost
But none of this is guaranteed by GR.
(9/)
• the star already reached its horizon
• the horizon already exists “now”
• the singularity already formed
• the image we see is just a delayed ghost
But none of this is guaranteed by GR.
(9/)
November 13, 2025 at 10:10 PM
Picture (b) implicitly assumes:
• the star already reached its horizon
• the horizon already exists “now”
• the singularity already formed
• the image we see is just a delayed ghost
But none of this is guaranteed by GR.
(9/)
• the star already reached its horizon
• the horizon already exists “now”
• the singularity already formed
• the image we see is just a delayed ghost
But none of this is guaranteed by GR.
(9/)
AND GR permits (c) just as well.
GR does not discriminate.
We do. GR is ambiguous on distant simultaneity.(8/)
GR does not discriminate.
We do. GR is ambiguous on distant simultaneity.(8/)
November 13, 2025 at 10:09 PM
AND GR permits (c) just as well.
GR does not discriminate.
We do. GR is ambiguous on distant simultaneity.(8/)
GR does not discriminate.
We do. GR is ambiguous on distant simultaneity.(8/)
A second (related) issue:
Physicists interpret collapse using picture (b)—a naive Cartesian reading of a non-Euclidean geometry, described in one coordinate basis, projected onto a Euclidean plane, and then taken to represent ontological reality.
But GR only gives us (a) (7/)
Physicists interpret collapse using picture (b)—a naive Cartesian reading of a non-Euclidean geometry, described in one coordinate basis, projected onto a Euclidean plane, and then taken to represent ontological reality.
But GR only gives us (a) (7/)
November 13, 2025 at 10:09 PM
A second (related) issue:
Physicists interpret collapse using picture (b)—a naive Cartesian reading of a non-Euclidean geometry, described in one coordinate basis, projected onto a Euclidean plane, and then taken to represent ontological reality.
But GR only gives us (a) (7/)
Physicists interpret collapse using picture (b)—a naive Cartesian reading of a non-Euclidean geometry, described in one coordinate basis, projected onto a Euclidean plane, and then taken to represent ontological reality.
But GR only gives us (a) (7/)
So the objects that actually collided were:
- horizon-approaching Kerr-like balls,
not
- already-formed black holes with vacuum interiors and singularities.
The “two black holes collide” story is a modelling convenience—not something GR’s causal structure supports.
(6/)
- horizon-approaching Kerr-like balls,
not
- already-formed black holes with vacuum interiors and singularities.
The “two black holes collide” story is a modelling convenience—not something GR’s causal structure supports.
(6/)
November 13, 2025 at 10:08 PM
So the objects that actually collided were:
- horizon-approaching Kerr-like balls,
not
- already-formed black holes with vacuum interiors and singularities.
The “two black holes collide” story is a modelling convenience—not something GR’s causal structure supports.
(6/)
- horizon-approaching Kerr-like balls,
not
- already-formed black holes with vacuum interiors and singularities.
The “two black holes collide” story is a modelling convenience—not something GR’s causal structure supports.
(6/)
Applied to mergers:
The gravitational waves we detect were emitted during the merger event.
Since we detect them now—and since we can only ever receive signals from before horizon formation—it follows:
At the moment of collision, neither object had yet formed its horizon.
(5/)
The gravitational waves we detect were emitted during the merger event.
Since we detect them now—and since we can only ever receive signals from before horizon formation—it follows:
At the moment of collision, neither object had yet formed its horizon.
(5/)
November 13, 2025 at 10:08 PM
Applied to mergers:
The gravitational waves we detect were emitted during the merger event.
Since we detect them now—and since we can only ever receive signals from before horizon formation—it follows:
At the moment of collision, neither object had yet formed its horizon.
(5/)
The gravitational waves we detect were emitted during the merger event.
Since we detect them now—and since we can only ever receive signals from before horizon formation—it follows:
At the moment of collision, neither object had yet formed its horizon.
(5/)
Therefore every signal we detect was emitted while the collapsing objects were still outside their horizons.
The photons/GWs we detect now were emitted in the pre-horizon phase.
There’s no way around this — it’s pure causality.
(4/)
The photons/GWs we detect now were emitted in the pre-horizon phase.
There’s no way around this — it’s pure causality.
(4/)
November 13, 2025 at 10:07 PM
Therefore every signal we detect was emitted while the collapsing objects were still outside their horizons.
The photons/GWs we detect now were emitted in the pre-horizon phase.
There’s no way around this — it’s pure causality.
(4/)
The photons/GWs we detect now were emitted in the pre-horizon phase.
There’s no way around this — it’s pure causality.
(4/)
No event on or inside an event horizon ever lies in an external observer’s past light cone.
That’s literally what a horizon is.
So everything we detect carries information from before horizon formation.
(3/)
That’s literally what a horizon is.
So everything we detect carries information from before horizon formation.
(3/)
November 13, 2025 at 10:07 PM
No event on or inside an event horizon ever lies in an external observer’s past light cone.
That’s literally what a horizon is.
So everything we detect carries information from before horizon formation.
(3/)
That’s literally what a horizon is.
So everything we detect carries information from before horizon formation.
(3/)
We only detect signals from our past light cone —
that includes:
• photons (EM observations)
• gravitational waves (LIGO/Virgo/KAGRA)
Nothing else can reach us.
(2/)
that includes:
• photons (EM observations)
• gravitational waves (LIGO/Virgo/KAGRA)
Nothing else can reach us.
(2/)
November 13, 2025 at 10:06 PM
We only detect signals from our past light cone —
that includes:
• photons (EM observations)
• gravitational waves (LIGO/Virgo/KAGRA)
Nothing else can reach us.
(2/)
that includes:
• photons (EM observations)
• gravitational waves (LIGO/Virgo/KAGRA)
Nothing else can reach us.
(2/)
“Person with proven track record in analytical thinking thinks argument I’d hoped would be accessible to people with capacity for analytical thinking is right.”
I’ll take it!! 😂
I’ll take it!! 😂
November 12, 2025 at 5:29 PM
“Person with proven track record in analytical thinking thinks argument I’d hoped would be accessible to people with capacity for analytical thinking is right.”
I’ll take it!! 😂
I’ll take it!! 😂
Thanks, Glenn! I appreciate the feedback.
November 12, 2025 at 5:04 PM
Thanks, Glenn! I appreciate the feedback.
Yep that’s right! Actually figure a is essentially identical to figure 2 in the Penrose article I cited. It’s the classic collapse narrative, which you’ll also find in Penrose (1965) or MTW, for instance. I’m truly not trying to straw man here.
November 12, 2025 at 4:35 PM
Yep that’s right! Actually figure a is essentially identical to figure 2 in the Penrose article I cited. It’s the classic collapse narrative, which you’ll also find in Penrose (1965) or MTW, for instance. I’m truly not trying to straw man here.
Hey thanks for reading and sharing! I’m honestly curious if anyone thinks I skipped a beat in my logic. Unfortunately, “I think Penrose and Hawking misunderstood black holes” tends to hit a brick wall with my colleagues.
November 12, 2025 at 4:32 PM
Hey thanks for reading and sharing! I’m honestly curious if anyone thinks I skipped a beat in my logic. Unfortunately, “I think Penrose and Hawking misunderstood black holes” tends to hit a brick wall with my colleagues.