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Joined 3 years ago
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Cake day: June 12th, 2023

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  • The distance does matter. There are ways of measuring/estimating distances other than red shift. So basically you plot the distances against the red shift and if the relation is linear, the rate of expansion is constant, and that isn’t the case. Interestingly, it seems lately that the rate is different based on which way of measuring you use. Something is probably wrong and nobody knows what. That is exciting, because this is how you discover new things.






  • It also depends how you define physical matter.

    If it’s something you cam touch, then there definitely is, starting with neutrinos.

    If you mean particles we know about, can describe and sort of understand, then there’s dark matter, which is probably particles we don’t know yet, but have several candidates we didn’t manage to confirm or disprove yet. They can only interact by gravitational (and perhaps weak?) force.

    If you mean something we know at least something solid about, there’s dark energy, which isn’t absolutely 100% certain that it exists, but is widely accepted.

    If you mean something physics doesn’t detect and try to explain, then obviously not.








  • Lab animals don’t just run around. If they escape, there’s a serious problem in the research facility. Their teeth are only a concern for the researchers working with them.

    Everyone would be happy if we had an easier model than animals. If organoids could give us all the answers we get from lab animals, all the scientists would be happy. Not only would it get rid of many ethical issues (and associated administrative), it would also be cheaper. Sadly, it’s not the case and we cannot effectively replace lab animals by other model systems. Not for many applications anyway.