4 ms·
This is a great introduction into how real astrophysics is done. We don't know how far away things are until we measure, but our measurements are never precise
by ltbarcly3 3y ago
This is a great introduction into how real astrophysics is done. We don't know how far away things are until we measure, but our measurements are never precise, and we don't have very many 'calibrated' distances to compare to. Little by little it's possible to exclude possibilities and narrow down on the likely true value.
- ForOldHack 3y agoI almost got my degree on astrophysics. Yes, I read a lot of bad and good textbooks. This one is rather brilliant, lucid, and well done. But I have to follow up with: "Well, but... how do we really know?" A: We have followed up well worn paths of scientific inquiry, and looked at our assumptions, in designing an experiment that, we assume to fail. When it does not follow our assumption, then we can only rule out failure, and call it a success. This follows centuries of this type of exacting and painstaking scientific work. Although I would normally have 10 ~ 12 citations of very diverse work, that exercise is left to the reader.
- eichin 3y agoIndeed, this might be good methodology background for the current "crisis in cosmology" where new JWST observations "close the gap" so that it no longer includes some previous upper/lower bounds at all ( https://www.youtube.com/watch?v=-kTe0xRAU1w https://www.youtube.com/watch?v=-kTe0xRAU1w for a scicomm explainer with more detail )
- ltbarcly3 3y agoWell, and the crisis! The allowed regions from different methodologies don't overlap, pointing to one of the pillars of cosmology potentially being wrong.