instruments.md

Instruments for Falsification

Status: CANONICAL

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Instrument Overview

Instrument	Operator	Measurement	SSZ Prediction	Timeline
NICER	NASA/GSFC	NS mass-radius, redshift	z_SSZ = z_GR + 13%	2025–2027
NANOGrav	Int. Consortium	Pulsar timing	Δt_SSZ = Δt_GR + 30%	2025–2028
ngEHT	EHT Collaboration	BH shadow (high res)	Shadow -1.3% vs GR	2028–2030
XMM-Newton	ESA	X-ray redshift of NS	Confirm +13%	Ongoing
GRAVITY/VLTI	ESO	S-star orbits (Sgr A*)	SSZ ≡ GR (weak field)	Ongoing
SKA	Int. Consortium	Pulsar timing (precision)	Shapiro +12%	2028+
LISA	ESA/NASA	Gravitational waves	Modified ringdown freq	2034+

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Detailed Instrument Profiles

NICER (Neutron Star Interior Composition Explorer)

• Location: International Space Station
• Capability: X-ray timing of millisecond pulsars
• Key targets: PSR J0030+0451, PSR J0740+6620
• SSZ relevance: Direct NS mass-radius measurement → redshift comparison
• Precision needed: Δz/z < 5% to distinguish SSZ from GR

NANOGrav (North American Nanohertz Observatory for Gravitational Waves)

• Capability: Pulsar timing arrays
• Key data: 15-year dataset (2023 release)
• SSZ relevance: Strong-field timing residuals
• Precision needed: Δt < 10% to distinguish

Next-Generation EHT (ngEHT)

• Status: In development
• Improvement: 3-10x resolution over current EHT
• SSZ relevance: BH shadow diameter measurement
• Precision needed: 1.3% shadow size resolution

GRAVITY/VLTI

• Location: Very Large Telescope Interferometer, Paranal, Chile
• Objects: S2, S0-2 and other S-stars near Sgr A*
• SSZ relevance: Weak-field validation (SSZ = GR)
• Anti-circularity: Data not used for SSZ calibration

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Experimental Data Sources

ESO S-Star Data (Sgr A*)

• GRAVITY Collaboration, ESO
• Perihelion precession, redshift comparison
• Data not used for SSZ calibration (anti-circularity)

NICER Neutron Star Data

• NASA Goddard Space Flight Center
• Mass-radius determination, redshift predictions
• Prediction: z_SSZ = z_GR + 13% (testable!)

GPS Time Measurements

• US Naval Observatory, BIPM
• Time difference ground ↔ satellite = ~45.85 μs/day
• Weak-field validation (SSZ ≡ GR)
• Accuracy: < 1 ns/day

Pound-Rebka Experiment

• Gravitational redshift over 22.6 m height
• Δν/ν = 2.46 × 10⁻¹⁵
• Weak-field validation (SSZ ≡ GR, <0.01% deviation)

EHT Black-Hole Shadow

• M87* (2019), Sgr A* (2022)
• Shadow diameter measurement
• SSZ prediction: -1.3% smaller than GR

Gaia Stellar Catalog

• ESA Gaia Mission, DR3 (2022)
• Parallaxes, proper motions, radial velocities
• Stellar parameters for validation

Schumann Resonance Data

• Various observatories (Hylaty, Nagycenk)
• Fundamental frequency ~7.83 Hz and overtones
• Explorative scaling analysis (ssz-schumann repo)

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© 2025–2026 Carmen N. Wrede, Lino P. Casu