"매 spacetime 의 region where escape velocity > c". Schwarzschild (1916) solution → Hawking radiation (1974) → EHT M87* image (2019) + Sgr A* (2022) → 매 2026 modern view: 매 information paradox 의 holographic / ER=EPR resolution 의 frontier. 매 CS 측면에서는 매 information bound, holographic encoding, computational limit 의 reference physical system.
매 핵심
매 정의 / 종류
Schwarzschild (non-rotating, no charge): r_s = 2GM/c².
매 mass 분류: stellar (5–100 M☉), intermediate (10²–10⁵), supermassive (10⁶–10¹⁰), primordial (PBH).
매 entropy / information
Bekenstein–Hawking entropy: S = k·A / (4·ℓ_P²).
매 information 매 area 에 비례 — 매 holographic principle 의 origin.
Hawking T = ℏc³ / (8π·G·M·k_B) — 매 radiation 의 thermal.
매 information paradox: 매 unitary evolution vs thermal radiation. 2020 island formula (Penington, Almheiri 등) 의 Page curve 도출.
매 CS / 정보이론 연결
Holographic bound: 매 region 의 max info ≤ A / (4·ℓ_P²) bits.
Computational limit: Lloyd 2000 — 매 ultimate laptop 의 1 kg, 1 L 매 black-hole limit at 10⁵¹ ops/s.
Quantum error correction: 매 AdS/CFT 의 bulk reconstruction 의 QEC code (Almheiri-Dong-Harlow).
ER=EPR: 매 entanglement = wormhole — 매 quantum gravity 의 unification 의 hint.
💻 패턴
Schwarzschild radius
G,c,MSUN=6.67430e-11,2.99792458e8,1.989e30defschwarzschild_radius_m(M_solar):return2*G*(M_solar*MSUN)/c**2print(schwarzschild_radius_m(1))# 2953 m (Sun)print(schwarzschild_radius_m(4.3e6))# Sgr A*
Hawking temperature & lifetime
importmathhbar,kB=1.054571817e-34,1.380649e-23defhawking_T(M_kg):returnhbar*c**3/(8*math.pi*G*M_kg*kB)defevap_time_s(M_kg):return5120*math.pi*G**2*M_kg**3/(hbar*c**4)print(hawking_T(MSUN))# ~6e-8 Kprint(evap_time_s(MSUN)/3.15e16)# ~2e67 yr
lP2=2.612e-70# Planck area m^2defBH_entropy_bits(M_kg):rs=2*G*M_kg/c**2A=4*math.pi*rs**2returnA/(4*lP2)/math.log(2)print(f"{BH_entropy_bits(MSUN):.2e} bits")# ~1e77
Holographic bound check
defholographic_max_bits(area_m2):returnarea_m2/(4*lP2)/math.log(2)# 매 1 m² boundary 매 ~1e69 bits maximum.
Image-plane shadow radius (EHT-style)
defshadow_radius_uas(M_solar,distance_kpc):rs=schwarzschild_radius_m(M_solar)shadow_m=3*math.sqrt(3)*rs# photon ring diameter ≈ 5.196·r_s/2d_m=distance_kpc*3.086e19return(shadow_m/d_m)*(180/math.pi)*3600*1e6print(shadow_radius_uas(6.5e9,16800))# M87* ~ 42 µas
매 결정 기준
상황
Approach
Newtonian regime (r ≫ r_s)
Newtonian gravity
Static, spherical
Schwarzschild metric
Rotating astrophysical
Kerr metric
Quantum-gravity / info
Page curve + island formula
Holographic / dual CFT
AdS/CFT
Numerical merger
Numerical Relativity (Einstein Toolkit)
기본값: 매 astrophysics 면 Kerr, 매 CS / info-theoretic discussion 면 Bekenstein–Hawking + holographic bound.
🔗 Graph
🤖 LLM 활용
언제: 매 information-theoretic 한 entropy bound, 매 holographic / quantum gravity 의 thought experiment, 매 cosmology numerical estimation.
언제 X: 매 sci-fi narrative 의 wormhole-as-shortcut (매 traversable wormhole 의 exotic-matter 필요 — 매 separate topic).
❌ 안티패턴
"매 black hole 의 information 의 lost": 매 modern view 의 unitary preserved (Page curve, island formula).
"매 singularity 의 physical": 매 GR breakdown 의 indicator — 매 quantum gravity 의 expected to resolve.
"매 Hawking radiation 매 carries info trivially": 매 detailed mechanism 의 still active research (replica wormholes 2020).
Mixing M_BH ↔ r_s units: 매 SI (kg, m) vs geometrized (M = G·M_kg/c²) 매 cross-check 항상.