diff --git a/tests/rootfile/test_lawful_collapse_universe.py b/tests/rootfile/test_lawful_collapse_universe.py
index 5119fea..f1f0d93 100644
--- a/tests/rootfile/test_lawful_collapse_universe.py
+++ b/tests/rootfile/test_lawful_collapse_universe.py
@@ -103,6 +103,21 @@ def test_field_tensor_is_deterministic():
     assert first["field_energy"] > 0
 
 
+def test_field_tensor_accepts_canonical_bar_list():
+    market_state = {
+        "ohlcv": [
+            {"high": 1.1010, "low": 1.0990, "close": 1.1000},
+            {"high": 1.1020, "low": 1.1000, "close": 1.1015},
+        ],
+        "microstructure": {"mid": 1.1015},
+    }
+
+    tensor = compute_maxwell_tensor(market_state, {"phi": 0.2})
+
+    assert tensor["electric_impulse"] > 0
+    assert tensor["field_energy"] > 0
+
+
 def test_causal_violation_marks_field_inadmissible():
     tensor = {"magnetic_liquidity": 0.00001, "electric_impulse": 0.00001}
     result = check_causal_reach({"entry": 1.0, "target": 2.0}, tensor)
diff --git a/trading/fields/maxwell_tensor.py b/trading/fields/maxwell_tensor.py
index 1efc779..a665b20 100644
--- a/trading/fields/maxwell_tensor.py
+++ b/trading/fields/maxwell_tensor.py
@@ -2,7 +2,7 @@
 
 from __future__ import annotations
 
-from typing import Dict, Iterable
+from typing import Any, Dict, Iterable
 
 
 def _last(values: Iterable[float], default: float = 0.0) -> float:
@@ -10,13 +10,27 @@ def _last(values: Iterable[float], default: float = 0.0) -> float:
     return float(seq[-1]) if seq else default
 
 
+def _series(ohlcv: Any, key: str) -> list[float]:
+    if isinstance(ohlcv, dict):
+        values = ohlcv.get(key, [])
+    elif isinstance(ohlcv, list):
+        values = [
+            item.get(key)
+            for item in ohlcv
+            if isinstance(item, dict)
+        ]
+    else:
+        values = []
+    return [float(value) for value in values if value is not None]
+
+
 def compute_maxwell_tensor(market_state: Dict, geometry_data: Dict) -> Dict[str, float]:
     """Compute a compact field tensor from OHLCV, microstructure, and geometry."""
     ohlcv = market_state.get("ohlcv", {}) if isinstance(market_state, dict) else {}
     micro = market_state.get("microstructure", {}) if isinstance(market_state, dict) else {}
-    close = [float(value) for value in ohlcv.get("close", []) if value is not None]
-    high = [float(value) for value in ohlcv.get("high", []) if value is not None]
-    low = [float(value) for value in ohlcv.get("low", []) if value is not None]
+    close = _series(ohlcv, "close")
+    high = _series(ohlcv, "high")
+    low = _series(ohlcv, "low")
 
     latest_close = _last(close, float(micro.get("mid", 0.0) or 0.0))
     prev_close = close[-2] if len(close) >= 2 else latest_close