Imprint of Distortions in the Oort Cloud on the CMB Anisotropies
Bibliographic record
Abstract
We study the effect of a close encounter of a passing star on the shape of the inner Oort Cloud, using the impulse approximation. The deviation of the perturbed Oort Cloud from sphericity adds angular fluctuations to the brightness of the Cosmic Microwave Background (CMB) due to thermal emission by the comets. An encounter with a solar-mass star at an impact parameter of $1750 \au$, as expected based on the abundance and velocity dispersion of stars in the solar neighborhood, leads to a quadrupole moment in the square of the fractional CMB intensity fluctuation of $C_2 = 4.5 \times 10^{-15}, 6.7 \times 10^{-12}, 1.1 \times 10^{-9}$ at $ν= 30, 353, 545 \GHz$ (these being the frequency bands of the upcoming Planck satellite). We also quantify the quadrupole spectral distortions produced by the Scattered Disc, which will exist regardless of any perturbation and the subsequent shape of the Oort Cloud. For comparison, the square fractional temperature fluctuation quadrupole moment predicted by the current cosmological model is $C_2 = 1.76 \times 10^{-10}$, which corresponds to fluctuations in the CMB intensity of $C_2 = 2.9 \times 10^{-10}, 6.8 \times 10^{-9}, 1.6 \times 10^{-8}$ at $ν= 30, 353, 545 \GHz$. Finally, we discuss how a measurement of the anisotropic spectral distortions could be used to constrain the trajectory of the closest stellar fly-by.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.001 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".