Physics is highly mathematical and as such, can indeed be "tested" (i.e. proven) to be consistent with mathematical laws. This is fairly straightforward (for suitably mathematically literate people). The real issues are: 1. can the theory make testable predictions that can be verified by observation? e.g. string theory has had issues with this. 2. what does "mean"? e.g. negative mass, spooky action at a distance, spa…
1. OpenGL makes good predictions. Why not to switch to OpenGL terms when talking about physics?
Because physicists would find it totally unsuitable for their requirements?
Inertia isn't "resistance to change". It's defined by Newton's second law, F = ma . Force and acceleration are directional vectors, and mass is scalar. In the form of the equation favored by my high school physics teacher, a = F/m , we see that when a force is exerted on an object with positive mass, the object will accelerate in the same direction as the force, in inverse proportion to its own mass. But it's very ea…
Thanks, that's obviously a much better way to think about it. However, you're wrong in at least the typical physics definition of inertia found in dictionaries is in fact, "resistance of change (velocity, acceleration, momentum)." In that same framework, the maths definition of inertia is also momentum = mv and a google search confirms this. What would negative momentum even look like? Because that's not just movemen…
You're talking about relativistic mass, but that isn't a commonly used concept anymore. Today it is indeed the norm to think of "mass" as being the mass at rest. Massless particles are really massless and have momentum without having mass.
In which case, we seem back to having two things distorting spacetime. Could mass just be the momentum of massless particles going in really small circles such that you can pack them together and call them matter?
Energy distorts spacetime. Mass only distorts spacetime because it is a form of energy. Light is also a form of energy.
> If you have an infinite space of particle parameters and a series of tests keeps eliminating large swaths of this space, at some point it feels like you're playing a god of inbetweens game a la creationists arguing using gaps in the fossil record. Or you're getting closer to finding out what the real parameters are? If you eliminate all possibilities and have to make up some new parameters, sure, that feels like yo…
> Or you're getting closer to finding out what the real parameters are? By that metric, epicycles were rock-solid.
> "They are mentioned" No, they were not mentioned. If they were, you would be quoting it. > '"2013: ΛCDM provides an excellent fit to the improved CMB data" As I've said, that's the "item 3" from the 5 item list, and it's ultimately confirmed by ESA's Planck satellite results in 2013. That is a strong confirmation.' You have to read the entire quote. This "fit" was a post-diction, not a pre-diction: "in order to obt…
What is your support for that claim? Can you quote other sources? I can quote my sources: Here are documented two independent approaches in estimating baryonic density: one is calculations based on the Big Bang Nucleosynthesis D/H ratio and another one is the values measured by the satellites observing the SMB. Note the two decades of similar values using both approaches: https://lambda.gsfc.nasa.gov/education/graphi…
My model was the following. Take the classical rubber sheet, place two marbles on it, then stretch the rubber sheet. The marbles are unbound and therefore expand away from each other with the expanding rubber sheet. Now connect the two marbles with a spring and again stretch the rubber sheet. The rubber sheet expands everywhere just as before but now the spring prevents the marbles from being pulled apart and makes t…
Your italicized paragraph is a good clue. I started a reply which was getting too long and technical, with the aim of looking at three prongs. Post-Newtonian elements are at work, and it is easy to fool oneself thinking of the underlying one: metric gravitation and how it manifests within extended objects. (It does ; we can see that from the figure of the Earth and its internal structure, and from other roundish cele…
After reading the Karen Masters link and your first response a few times, I think I am starting to understand what you want to point out. If the universe were empty and expanding, then some light non-interacting test dust would indeed get pulled apart everywhere and at all length scales. But when we add matter and let it collapse, the collapsing matter kind of pulls spacetime with it as it collapses and may eventually reach a kind of equilibrium where the effects of the expansion and the collapsing matter cancel out locally leading to a non-expanding region. If this is kind of correct, I have a very wrong model of the effect of mass on spacetime and have to rewatch Susskind's lectures on general relativity.
I'm curious about the idea of "allow[ing] negative masses to not only exist, but to be created continuously." Given the law (in the scientific sense) that matter/energy cannot be created or destroyed, on a scale of 1 to FTL travel, how crazy is this idea?
I thought it was less a law and more of an observation.
> "They are mentioned" No, they were not mentioned. If they were, you would be quoting it. > '"2013: ΛCDM provides an excellent fit to the improved CMB data" As I've said, that's the "item 3" from the 5 item list, and it's ultimately confirmed by ESA's Planck satellite results in 2013. That is a strong confirmation.' You have to read the entire quote. This "fit" was a post-diction, not a pre-diction: "in order to obt…
What is your support for that claim? Can you quote other sources? I can quote my sources: Here are documented two independent approaches in estimating baryonic density: one is calculations based on the Big Bang Nucleosynthesis D/H ratio and another one is the values measured by the satellites observing the SMB. Note the two decades of similar values using both approaches: https://lambda.gsfc.nasa.gov/education/graphi…
>"I do disagree with the assertion that I often see, and remains a widespread misconception among scientists, that MOND does not do a good job of explaining cosmic phenomena. I’ve been through all that, and it is simply incorrect to say dark matter is always better outside of galaxies. Sure, it has shortcomings, but often dark matter only appears to be better because it declines to make a comparably testable prediction. Clusters of galaxies are a great example: MOND is off by a factor of 2 in mass (20% in velocity). Dark matter makes no prediction. Anything over the luminous mass is OK. The rest is dark. It doesn’t matter if that’s a factor of 2 or 5 (the modern value) or 6 (the cosmic value) or ~100 (Zwicky’s value). Being a factor of 2 off only sounds bad because there is a definite prediction! With dark matter we don’t care what that factor is because we have no prediction – at least, not one that can not be fudged."
1. OpenGL makes good predictions. Why not to switch to OpenGL terms when talking about physics?
Because physicists would find it totally unsuitable for their requirements?
Why match is better for that? To compute prediction, you will need to use computer and compiler, so it better to talk directly in these terms because of (1) (see above).
In which case, we seem back to having two things distorting spacetime. Could mass just be the momentum of massless particles going in really small circles such that you can pack them together and call them matter?
What you described sounds like a geon. https://en.wikipedia.org/wiki/Geon_(physics)
Oh, cool, yep. I didn't know that's what they are. I have basically been wondering if all matter is variations of those.
