Boundary representations, geometry of matrix ranges, and C$^*$-envelopes of finite-dimensional operator systems
Bibliographic record
Abstract
An analysis of the boundary representations and C$^*$-envelopes of some finite-dimensional operator systems $\mathcal R$ is undertaken by considering relationships between operator-theoretic properties of a $d$-tuple $\mathfrak x=(x_1,\dots, x_d)$ of elements in a unital C$^*$-algebra $\mathcal A$ and operator-system properties of the linear span $\mathcal O_{\mathfrak x}$ of $\{1_\mathcal A,x_1,x_1^*,\dots,x_d,x_d^*\}$. This approach lends itself well to the study of certain phenomena in single- and several-variable operator theory, such as the Smith-Ward property. The matrix range of a $d$-tuple of elements $\mathfrak x$ is matrix-affinely homeomorphic to the matrix state space of the operator system determined by $\mathfrak x$, and many of our methods connect the geometry of these compact matrix convex sets to operator system properties, including various forms of nuclearity and lifting properties.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".