The current theoretical model for the composition of the universe is that it's made of normal matter, dark energy and dark matter. A new University of Ottawa study challenges this.
This model combines two ideas—about how the forces of nature decrease over cosmic time and about light losing energy when it travels a long distance. It’s been tested and has been shown to match up with several observations, such as about how galaxies are spread out and how light from the early universe has evolved.
These hypotheses never seem to stand up to rigorous analysis. Still, always welcome the discussion.
Absolutely. On the one hand, having ~26% of the known universe consisting of a substance that we cannot detect directly leaves a lot of questions open. On the other hand; dark matter is postulated because otherwise things like galaxy rotation curves don’t match what we believe they should be from general relativity, and this theory doesn’t seem to address that.
I’m no expert, and I don’t think we know for sure, but it sounds like it might be related to the increase in vacuum energy from the added space. It’s also possible the total amount of net energy in the universe is 0 and conserved
At some point we may have to review some theories though. The idea that light would lose energy over extra long distances at least makes sense unlike some kind of latter that we can’t detect and we can’t figure out why it would either still be there but not more than it is.
This is kind of how time was supposed to be absolute. Einstein never received a Nobel for the theory of relativity because of how suspicious it seemed at the time.
There being a substance that does not interact with light at all doesn’t seem that far fetched to me. There is nothing in the laws of the universe that says “Humans must be able to detect everything that exists because otherwise it wouldn’t make sense.”
It feels entirely possible that we won’t be able to detect dark matter through any conventional means that we currently have.
It’s not about humans. It’s about science. “there is dark matter that doesn’t interact with matter” can as well be “there is magic, and I cannot be proven wrong”.
Dark matter does interact with matter, though: it interacts gravitationally. It just does not interact in other ways (that we know of yet). All you would have to do to disprove the existence of dark matter is to show that some things interact with it gravitationally but others don’t. However, this is not what we see; what we actually see is a whole bunch of separate things that all experience the effect of the existence of dark matter in the same way. It’s effectiveness as an explanation in this regard is exactly what makes it so difficult to dethrone.
This is the same researcher that said the universe is 26.7 billion years old based on the JWST data instead of 13.8.
Happy to see ideas thrown out there to help us understand what dark matter is, but I’m really looking forward to all the random videos that eventually come out explaining why it holds up against a whole bunch of observational evidence while it ignores all the other observational evidence it doesn’t hold up against.
These hypotheses never seem to stand up to rigorous analysis. Still, always welcome the discussion.
Absolutely. On the one hand, having ~26% of the known universe consisting of a substance that we cannot detect directly leaves a lot of questions open. On the other hand; dark matter is postulated because otherwise things like galaxy rotation curves don’t match what we believe they should be from general relativity, and this theory doesn’t seem to address that.
https://en.wikipedia.org/wiki/Bullet_Cluster#Significance_to_dark_matter
Also, light ‘losing energy’ would be a violation of the first law of thermodynamics, unless it loses it ‘to’ somewhere.
Light does actually just lose energy to nowhere in our current understanding of expanding space.
How does this reconcile with the first law of thermodynamics? Or does it just not?
I’m no expert, and I don’t think we know for sure, but it sounds like it might be related to the increase in vacuum energy from the added space. It’s also possible the total amount of net energy in the universe is 0 and conserved
At some point we may have to review some theories though. The idea that light would lose energy over extra long distances at least makes sense unlike some kind of latter that we can’t detect and we can’t figure out why it would either still be there but not more than it is.
This is kind of how time was supposed to be absolute. Einstein never received a Nobel for the theory of relativity because of how suspicious it seemed at the time.
There being a substance that does not interact with light at all doesn’t seem that far fetched to me. There is nothing in the laws of the universe that says “Humans must be able to detect everything that exists because otherwise it wouldn’t make sense.”
It feels entirely possible that we won’t be able to detect dark matter through any conventional means that we currently have.
It’s not about humans. It’s about science. “there is dark matter that doesn’t interact with matter” can as well be “there is magic, and I cannot be proven wrong”.
Dark matter does interact with matter, though: it interacts gravitationally. It just does not interact in other ways (that we know of yet). All you would have to do to disprove the existence of dark matter is to show that some things interact with it gravitationally but others don’t. However, this is not what we see; what we actually see is a whole bunch of separate things that all experience the effect of the existence of dark matter in the same way. It’s effectiveness as an explanation in this regard is exactly what makes it so difficult to dethrone.
Dark matter is exactly like adding a constant to your equation so that it fits the numbers.
If by “constant” you mean “3D distribution that explains not just one equation but lots of separate observations”, then sure, it’s just like that.
This is the same researcher that said the universe is 26.7 billion years old based on the JWST data instead of 13.8.
Happy to see ideas thrown out there to help us understand what dark matter is, but I’m really looking forward to all the random videos that eventually come out explaining why it holds up against a whole bunch of observational evidence while it ignores all the other observational evidence it doesn’t hold up against.