feat: Add comprehensive Location Proofs research documentation

docs/core-concepts/location-proofs.md

@@ -1,30 +1,40 @@
 # Location Proofs
 
-Location proofs are verification evidence that can be attached to location attestations. While location attestations contain the actual spatial data (coordinates, geometries, etc.), location proofs provide evidence or verification of the authenticity of that spatial data.
+Location proofs are digital artifacts that combine multiple independent pieces of evidence to support claims about *where and when* events occur. They serve as the verification layer for location attestations in the Astral ecosystem.
 
-## What are Location Proofs?
+## Core Concepts
+
+A **location stamp** is a single piece of verifiable evidence (e.g., a GNSS reading, an IP lookup, or a signed affidavit).
+A **location proof** is what you get when multiple stamps are combined and verified together to create a higher-confidence claim.
 
 Location proofs serve as the verification layer for location attestations. They:
 
-- Provide evidence that a claim about a location is valid
+- Combine multiple independent evidence sources to increase confidence
 - Can be generated through various verification strategies
 - Are attached to location attestations as part of the Location Protocol
+- Make location fraud more difficult through multifactor verification
 
-## Types of Location Proofs
+## Evidence Strategies
 
-The Location Protocol supports many different approaches to verification:
+The Location Protocol supports seven broad categories of location evidence:
 
-- **Authority-based proofs**: Verification from trusted entities like event organizers
-- **Social proofs**: Verification from other users who can confirm location claims
-- **Hardware-based proofs**: Evidence from devices like Bluetooth beacons, NFC, or RFID
-- **Network-based proofs**: Evidence from network triangulation or signal analysis
-- **Sensor data proofs**: Evidence from environmental readings that match expected values
+- **[Machine Identifiers](../location-proofs/strategies/machine-identifiers.md)**: Wi-Fi, Bluetooth, cell towers, IP addresses
+- **[Network Measurements](../location-proofs/strategies/network-measurements.md)**: GNSS, RTT latency, signal strength
+- **[Sensor Data](../location-proofs/strategies/sensor-data.md)**: IMU, camera, microphone, environmental sensors
+- **[Delegated](../location-proofs/strategies/delegated.md)**: Third-party services like ride logs, utility bills
+- **[Social](../location-proofs/strategies/social.md)**: Peer attestations and community validation
+- **[Authority](../location-proofs/strategies/authority.md)**: Institutional records and certifications
+- **[Legal](../location-proofs/strategies/legal.md)**: Formal documents like bills of lading
 
 ## Relationship to Location Attestations
 
 Location attestations are the primary data structure in the Location Protocol, while location proofs provide the evidence that makes these attestations trustworthy:
 
 - **Location attestation**: "I was at coordinates 37.7749° N, 122.4194° W at 2:00pm"
-- **Location proof**: Evidence supporting that claim, such as a beacon signal, network data, or third-party verification
+- **Location proof**: Multiple pieces of evidence supporting that claim, such as GNSS data + Wi-Fi signals + device attestation
+
+## Research & Implementation
+
+For detailed technical research on location proof strategies, signals, and implementation approaches, see the [Location Proofs](../location-proofs/overview.md) section.
 
-The Location Protocol is designed to accommodate various proof strategies through the [Location Proof Extensions](../location-protocol/strategies-recipes.md) framework.
+The Location Protocol accommodates various proof strategies through the [Location Proof Extensions](../location-protocol/strategies-recipes.md) framework.