Allzén, Simon (2025) Evidential Reconfiguration as Bayesian Confirmation For Dark Matter in 1974: How Existing Data Become Evidence in New Structures. [Preprint]

	Text Evidential_Reconfiguration_as_Bayesian_Confirmation_For_Dark_Matter.pdf Download (219kB)
	Text bayes.pdf Restricted to Repository staff only Download (300kB)

Abstract

The 1974 papers by Ostriker et al. [1974] and Einasto et al. [1974] are considered by many to be pivotal in establishing the epistemic foundations for the dark matter hypothesis. From a theory confirmation point of view, the circumstances surrounding this pivot are difficult to reconcile with common approaches to epistemic support. First, the papers did not introduce any new observations. Second, they synthesized existing data from two separate contexts to construct a hypothesis under which the joint data became evidentially relevant. Third, this synthesis was motivated in part by non-empirical reasons. The situation excludes both temporal novelty and use novelty because already known data was used in the construction of the hypothesis. Yet, the papers are widely regarded as epistemically transformative. I argue that a Bayesian can model the epistemic significance of the 1974 papers without concession. By recognizing how the papers reconfigured the existing data to bear on a missing-mass hypothesis, a novel epistemic aspect emerges. By introducing a shared halo parameterization, they made the previously disjoint data mutually constrained, thereby changing their evidential role. I develop this idea through two concepts — evidential reconfiguration and structural novelty — leveraged through Myrvold’s Bayesian account of unification. The result makes Bayesianism faithful to the inferential practices in this significant part of scientific history, explains how the 1974 papers strengthened the evidential case for dark matter, and expands the Bayesian toolbox with a way to treat novel structure as epistemologically salient.

---

Export/Citation:

EndNote | BibTeX | Dublin Core | ASCII/Text Citation (Chicago) | HTML Citation | OpenURL

Social Networking:

Share |

---

Item Type:	Preprint
Creators:	Creators Email ORCID Allzén, Simon simon.allzen@philosophy.su.se 0000-0002-6124-8152
Keywords:	Bayesianism, Unification, Dark Matter, Theory confirmation
Subjects:	Specific Sciences > Physics > Astrophysics General Issues > Confirmation/Induction Specific Sciences > Physics > Cosmology General Issues > Evidence
Depositing User:	Dr Simon Allzén
Date Deposited:	21 Jan 2026 13:41
Last Modified:	21 Jan 2026 13:41
Item ID:	27966
Subjects:	Specific Sciences > Physics > Astrophysics General Issues > Confirmation/Induction Specific Sciences > Physics > Cosmology General Issues > Evidence
Date:	15 December 2025
URI:	https://philsci-archive.pitt.edu/id/eprint/27966

Available Versions of this Item

• Bayesian Unification in the History of Dark Matter: Confirmation by Restructuring Old Evidence. (deposited 15 Dec 2025 20:22)
  • Evidential Reconfiguration as Bayesian Confirmation For Dark Matter in 1974: How Existing Data Become Evidence in New Structures. (deposited 21 Jan 2026 13:41) [Currently Displayed]

Monthly Views for the past 3 years

Monthly Downloads for the past 3 years

Plum Analytics

Actions (login required)

View Item