SciPost Submission Page
A Short Introduction to Cosmology and its Current Status
by Pedro G. Ferreira, Alexander Roskill
Submission summary
| Authors (as registered SciPost users): | Pedro Ferreira |
| Submission information | |
|---|---|
| Preprint Link: | scipost_202511_00041v1 (pdf) |
| Date submitted: | Nov. 18, 2025, 8:23 p.m. |
| Submitted by: | Pedro Ferreira |
| Submitted to: | SciPost Physics Lecture Notes |
| for consideration in Collection: |
| Ontological classification | |
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| Academic field: | Physics |
| Specialties: |
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| Approaches: | Theoretical, Computational, Phenomenological, Observational |
Abstract
The current cosmological model, known as the $\Lambda$-Cold Dark Matter model (or $\Lambda$CDM for short) is one of the most astonishing accomplishments of contemporary theoretical physics. It is a well-defined mathematical model which depends on very few ingredients and parameters and is able to make a range of predictions and postdictions with astonishing accuracy. It is built out of well-known physics - general relativity, quantum mechanics and atomic physics, statistical mechanics and thermodynamics - and predicts the existence of new, unseen components. Again and again it has been shown to fit new data sets with remarkable precision. Despite these successes, we have yet to understand the unseen components of the Universe and there has been evidence for inconsistencies in the model. In these lectures, we lay the foundations of modern cosmology.
Anonymous on 2025-11-19 [id 6049]
Not sure whether “Hubble constant” should be changed to “Hubble parameter”. I’ve sometimes read that “constant” is a misnomer since, in general, it is not constant in time. While that is true, the reason why it is called a constant is that it is like the constant a in y=ax, in contrast to y and x, which are variables. So the law is v=HD and H is the constant while v and D are variables. That H can change with time is a different issue.