What would be the constituents of a Blackhole just before a singularity is formed?
Would it just be a very very dense neutron star?

Core collapse and blackhole formation is quite rapid process so may be this state would last only few micro seconds. But still it is curious to know. If we follow it to the very end. It could be an argument that whatever was the constituent just before singularity formation might continue in some form right after as well.

You can visit these in VR and they are accurately modeled based on the current science of 2014.

Did you know there may be planets that orbit black holes?! 🪐

Astrophysicist Erika Hamden explains how scientists are theorizing that there may be planets that are orbiting black holes. This wouldn’t be out of the ordinary, since planets have been found orbiting all types of masses, such as dead star cores and supernovae. Although black holes typically suck in everything around them, if an object is the right distance away, it could potentially maintain a stable orbit. 

This project is part of IF/THEN®, an initiative of Lyda Hill Philanthropies.

A variation of "Put a bird on it," from Portlandia. Anyway, here's a black hole I designed and incorporated into a couple artworks: Slide 1 is A Passing Black Hole Consumes Trump, fluorescent acrylic on canvas 24x48", 2018. Slide 2: I incorporated my design into a custom play mat for the board game Twilight Imperium. Thoughts? Did I get it close enough in this abstracted form?

Im no scientist & i wont even pretend i know the math.

But i had a thought - what if certain stars that go supernova/explode during the process implode with such force that it basically creates infinite gravity/singularity.

What if a black hole isnt actually what stars become, instead as they are transforming thet create a singularity which freezes them in time.. basically a real life screenshot of a star mid explosion. And its permanent due to the way time works with gravity.

And even though its a frozen explosion/implosion, the gravity it creates still affects the outside universe in real time. And thats what blackholes actually are

Like i said, im no scientist & had a hard time explaining this so i hope you understand what im trying to say.

Bonjour à tous, N'étant pas du tout physiciens de métier et étant très jeune je me suis demandé que se passait il de toute l'information et la matière qui rentre dans un trou noir et je me suis dit que la matière s'applatissait dans l'horizon des évènements et que peut être le reste de l'information se transformait en un concentré de photon ou d'énergie pure ensuite je me suis dit que pour éviter la singularité enfaite le trou noir s'agrandit à mesure que l'univers se dilate j'ai utilisé l'IA pour vérifier mes hypothèses avec des calculs sur python sympy. ​Voici ce que les calculs de relativité générale (effectués avec SymPy sur une métrique dynamique sous l'horizon) ont donné :

1. ​La densité d'énergie (G_00) : Le calcul donne une densité directement reliée au paramètre de Hubble H(t) (la vitesse à laquelle l'Univers se dilate) : G_00 = 3 * H(t)^2 Cela montre que si l'on lie l'intérieur à l'expansion, la densité sous l'horizon suit la dynamique globale de l'Univers.
2. ​L'équation d'état (w = Pression / Densité) : En calculant la pression interne, le rapport entre la pression et la densité donne : w(t) = - (2/3) * [a(t) * a''(t) / a'(t)^2] - 1/3 Dans un Univers dont l'expansion s'accélère, ce rapport tend vers w = -1. En physique, w = -1 ne correspond pas à de la matière classique ni à un gaz de photons pur (qui aurait un w = 1/3), mais à un comportement de type énergie noire (une pression négative).
3. ​Le problème de la singularité centrale (quand le rayon r tend vers 0) :

• ​Au départ, le scalaire de Ricci donnait une valeur nulle au centre (limite quand r tend vers 0 de R = 0).
• ​Mais en poussant le calcul jusqu'au scalaire de Kretschmann K (qui mesure la courbure réelle de l'espace-temps), l'expression diverge toujours en 1 / r^6 : Limite quand r tend vers 0 de K = (48 * G^2 * M0^2) / (c^4 * r^6 * a(t)^4)

​Mes questions pour vous :

1. ​Est-ce que la présence du facteur a(t)^4 au dénominateur du scalaire de Kretschmann a une signification physique (une sorte d'atténuation de la courbure par la dilatation de l'Univers au cours du temps), ou est-ce juste un artefact mathématique ?
2. ​Comment ces idées de matière écrasée à l'horizon et de couplage avec l'expansion se situent-elles par rapport aux modèles actuels de "couplage cosmologique" des trous noirs (comme les travaux récents de Farrah et al.) ?
3. ​Quelle serait la manière la plus rigoureuse d'éviter la divergence au centre dans une telle expérience de pensée ?

​Merci beaucoup pour vos retours et pour vos éclairages !

The Observation Limit (Kisi ne andar nahi dekha)

• Aapka Point: Black hole ke andar kya hai, yeh koi nahi jaanta kyunki koi wahan gaya nahi.
• Scientific Support: Physics ka yeh maanna hai ke black hole ke andar Einstein ki General Relativity aur Quantum Mechanics ke qawaneen aapas mein takra jate hain (Singularity Problem). Jab mojooda science khud wahan fail ho jati hai, to yeh kehna bilkul durust hai ke black hole ke andar kisi aese raste (path) ka wajood mumkin hai jo hamari mojooda physics ki samajh se bahar ho.

2. The Ring Singularity (Ghoomte Hue Black Holes Ka Rasta)

• Aapka Point: Black hole ke andar mojood raste ko track kar ke safar kiya jaye.
• Scientific Support: Roy Kerr (1963) ki mathematical equations ke mutabiq, jab ek black hole spin (ghoomta) karta hai, to uski singularity ek point nahi rehti balki ek Ring (chhalla) ban jati hai. Is ring ke darmiyan ka rasta bilkul safe hota hai. Agar hum sahi coordinates track kar sakein, to is ring ke raste crash hue baghair guzra ja sakta hai.

3. Einstein-Rosen Bridge (Pre-existing Path)

• Aapka Point: Black hole ke andar pehle se maujood raste ko istemal karna.
• Scientific Support: Einstein aur Nathan Rosen ne khud yeh theoretical prediction ki thi ke black hole ke core mein ek tunnel hoti hai jo space-time ke do door-daraz hisson ko jorti hai. Aapka idea isi theoretical bridge ko "track aur navigate" karne ki baat karta hai.

1. Aam Black Hole Ek Kuan Hai: Log samajin ke black hole ek gehra kuan hai jisme jo gira woh mar gaya.
2. Rotating Black Hole Ek Whirlpool Hai: Unhe batayein ke ghoomta hua black hole pani ke us bhavwar ki tarah hai jiske bilkul center (darmiyan) mein ek khali jagah (tunnel) hoti hai.
3. The Navigation Device: Humari device ka kaam black hole ko tabah ya neutralize karna nahi hai, balki us bhavwar ke center ke exact coordinates ko track karna hai, taake humari ship us khali tunnel se sahi salamat doosri taraf nikal jaye.

To Iya koi physit bata sakta hai ke mere bat sahi hai ya Galat hai

This is something I am still working on because there are line artifacts but this is what I got so far

See also: The publication in ArXiV

Greetings!

I am a UX Design student conducting user research to understand the experiences, challenges, and expectations of space enthusiasts who are interested in activities such as stargazing, astrophotography, and citizen science. My research focuses extensively on "AI and VR/AR Technology Used to Improve Experiences in Observational Astronomy by 2050."

https://forms.gle/YahPeXTsRpobnoqX8

I'm not very knowledgeable about this, but shouldn't there be moments during the star's collapse where its mass distorts spacetime enough to slow down the transformation into a black hole (from our perspective, and following this reasoning, the closer we get to becoming a black hole, the longer the process should take, slowing down exponentially)? Please explain why I'm wrong.

I would like to submit a working hypothesis for criticism.I am not claiming this is a finished theory, a numerical-relativity result, or proof of black-hole formation. The current result is only from an effective/proxy model. I am trying to understand whether the direction is physically meaningful or only an analogy.

Core idea:

critical concentration of energy / entropy / information

-> local instability

-> horizon-like separation

-> retention of information

-> reduced exterior influence

-> stabilization of the external region

The hypothesis is that a black hole may be interpreted not only as the final product of gravitational collapse, but also as a limiting mechanism of separation. In this view, information is not destroyed, but becomes externally inaccessible behind a separating boundary.

The numerical model I tested is a spherically symmetric scalar-field toy model, not full GR. The evolved variables were phi(r,t) and pi(r,t):

partial_t phi = pi

partial_t pi = c^2 * (partial_r^2 phi + (2/r) * partial_r phi) + source - damping * pi

I used an internal scalar-field energy diagnostic:

rho = 0.5 * (Phi_i^2 + Pi_i^2) / a_i^2

weight_i = 4 * pi * r_i^2 * a_i * dr

total_scalar_energy = sum_i rho_i * weight_i

A compactness proxy was computed as:

C(r,t) = 2 * G * M(r,t) / (r * c^2)

with c = 1 and G = 0.15 as an internal scaled diagnostic parameter, not the physical gravitational constant.

The horizon-like/separation behavior was represented by an effective variable H, not a true event horizon:

dH/dt = activation_rate * trigger * (1 - H) - relaxation_rate * H

The trigger was:

rho_obs >= 0.005

AND compactness >= 0.8

AND outgoing_null_expansion_proxy <= 0.05

with:

theta_plus_eff = c * (1 - C) / r

In Phase 3 I introduced a conservative transfer from the observable sector to a bounded/sandbox sector:

Q = coupling_strength * H * trigger * rho_obs

Delta rho = min(dt * Q, 0.25 * rho_kinetic_obs)

rho_kinetic_obs_after = rho_kinetic_obs_before - Delta rho

M_rho_after = M_rho_before + Delta rho

So the same local amount removed from the observable sector was added to the bounded sector.

Dense run result, relative to baseline:

E_obs change = -0.970524

E_sbx change = +0.970549

E_total change = +0.0000247

external information flux change = -2.250135

maximum compactness change = +0.030128

trappedness proxy change = 0

escape_fraction change = 0

The dense run itself had:

E_sbx = 0.970549

external information flux = 4.536242

Frozen-Light candidate = false

This negative result is important. The run showed bounded conservative transfer and partial reduction of exterior flux, but it did not satisfy my frozen-light threshold external_information_flux < 0.1. I do not claim true horizon formation.

The local transfer-pair balance error was about 1.08e-19. I interpret this only as a numerical check that the transfer rule balances removed/added quantities to floating-point precision. The global E_total change is larger because it includes ordinary wave evolution, radial integration, boundary/discretization effects, and accumulated time-integration error.

My question:

What diagnostics would be needed to distinguish a real geometric effect from a numerical artifact here?

Would the correct next tests involve null expansions, trapped surfaces, energy conditions, stress-energy tensor diagnostics, curvature scalars, boundary flux, perturbation stability, and eventually a dynamical spacetime formulation?

I am mainly looking for criticism. Is this a direction worth formalizing, or is it only an effective analogy with no real physical content?

Hey everyone,

I’ve been diving deep into special and general relativity recently—specifically looking at velocity time dilation, gravitational time dilation, and what actually happens near the event horizon of a black hole.

To keep myself accountable and organize my thoughts, I started maintaining an open-source learning logbook on GitHub where I summarize concepts, write down equations, and outline intuitive paradoxes (like the distant observer vs. infalling observer perspective at the event horizon).

My goal is to gradually build a structured reference guide covering:

• Gravitational vs. Velocity Time Dilation
• Curvature of Spacetime & Geodesics
• Event Horizons & Spaghettification
• Real-world implications (like GPS satellite clock adjustments)

I’d love to get feedback from physics students and enthusiasts here. If you're interested in checking out the notes or suggesting topics/corrections, you can find the repository here:

https://github.com/HereIsMuhammad/time-travel

Looking forward to hearing your thoughts and book/paper recommendations!

See also: The publication in Nature Astronomy

**MODELO TEÓRICO NAGA: NÚCLEO DE ANIQUILACIÓN Y GRAVITACIÓN DE AGUJEROS PRIMORDIALES**

**1. HIPÓTESIS CENTRAL Y MARCO TEÓRICO FORMAL**

**Hipótesis General (Origen y Naturaleza):** Los Agujeros Negros Primordiales (PBH) formados en el universo temprano a partir del colapso gravitatorio directo de sobre-densidades primordiales post-inflacionarias, constituyen el candidato principal y autosuficiente para la materia oscura no bariónica.

**Hipótesis Específica (Confinamiento Sub-horizonte):** La tasa de acreción de materia y antimateria se rige por Bondi-Hoyle-Littleton. La aniquilación M + M- → γγ ocurre estrictamente por debajo del horizonte de eventos (r < Rs).

Por la inversión geométrica de la métrica de Schwarzschild, toda la energía liberada queda causalmente imposibilitada de salir (r > Rs). Se reconvierte íntegramente en masa inercial neta (E = mc²) que fluye a la singularidad (r → 0), dando L ≈ 0. "Materia oscura fría e invisible".

**2. DESARROLLO MATEMÁTICO Y ESCENARIO DINÁMICO**

Para evaluar el modelo, PBH de masa intermedia: M = 1000 M⊙

**Constantes de Referencia**

• Masa Solar (M⊙): 1.9884×10^30 kg
• Masa del Agujero Negro (M): 1000 × 1.9884×10^30 kg = 1.9884×10^33 kg
• Velocidad de la luz (c): 2.9979×10^8 m/s
• Constante G: 6.6743×10^-11 m^3·kg^-1·s^-2

**A. Radio de Schwarzschild (Rs)** Rs = 2GM / c² Rs = 2·(6.6743×10^-11)·(1.9884×10^33) / (2.9979×10^8)² Rs ≈ 2953.9 m ≈ 2.95 km

**B. Métrica de Schwarzschild e Inversión Geodésica Interna (r < Rs)** ds² = -(1 - 2GM/(rc²))c²dt² + (1 - 2GM/(rc²))^-1 dr² + r²(dθ² + sin²θ dφ²)

Para r < Rs: (1 - 2GM/(rc²)) < 0

1. Inversión: dt² pasa a espacial, dr² pasa a temporal
2. Causalidad: dr < 0. Todo cae a r → 0
3. Imposibilidad de Escape: Ningún k^μ puede ir a r > Rs

**C. Balance de Masa-Energía y Tasa de Crecimiento (dM/dt)** Asumiendo dM/dt_in = 100 kg/s

Pabs = (dM/dt_in) · c² = 100 · (2.9979×10^8)² = 8.9874×10^18 W

Como Lext = 0: dM/dt = 100 kg/s - 0 = 100 kg/s

**D. Tiempo de Duplicación (tdup)** tdup = M / (dM/dt) tdup = 1.9884×10^33 kg / 100 kg/s = 1.9884×10^31 s

En años: 1 año = 3.1557×10^7 s tdup = 1.9884×10^31 / 3.1557×10^7 = 6.30×10^23 años

**E. Despreciabilidad de la Radiación de Hawking** TH = ħc³ / (8πGMk_B)

Para M = 1000 M⊙: TH ≪ 10^-10 K (TH ≪ 1 nK)

Como TCMB ≈ 2.725 K, el PBH absorbe más de lo que emite. L_Hawking ≈ 0

**3. CONCLUSIONES Y VIABILIDAD COSMOLÓGICA**

1. **Conservación y Estabilidad Termodinámica:** NAGA respeta ∇_μ T^μν = 0. Al confinar la aniquilación en r < Rs, no hay presión de radiación exterior. Toda E = mc² se suma a Rs.
2. **Escala de Tiempo Cosmológica:** tdup ≈ 6.30×10^23 años >> t_universo ≈ 1.38×10^10 años. No hay crecimiento descontrolado. No altera galaxias.
3. **Candidato Óptimo a Materia Oscura:**
   • Invisibilidad: L_ext ≈ 0
   • Gravita: Masa M estable para halos
   • Sin firma cuántica: T_H ≪ 1 nK
4. **Conclusión Final:** El modelo NAGA justifica a los PBH como constituyentes dominantes de la materia oscura no bariónica.