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Not exactly. Imagine a china mug full of water. You can see the mug and the water being held in by the mug. Now imagine a glass of water. The purest most tran

Not exactly. Imagine a china mug full of water. You can see the mug and the water being held in by the mug. Now imagine a glass of water. The purest most transparent glass ever, with an identical refraction index as the water. You can't see the glass. You just see the water being held together by something. You don't know the glass exists. You 'invent' the glass to explain the behaviour of the water, seeing as you know the how the mug affects the water.

oldandtired 8y ago
The glass is testable though and would quickly be found. Dark matter and dark energy are assumed to exist with no experimental observations occurring. Every experiment has so far failed to show the existence of said entities. One possibility is that we do not have any way to find said entities with any means at our disposal. Another possibility is that they do not exist (just a figment of imagination) and that the theories requiring them are wrong. In that case, one should be looking for other theories that might be a more capable explanation. The question here is to determine when or whether we should stop looking for these entities and maybe move onto another model/theory. The basic assumption of all gravity based theories and models is that the universe is electrically neutral everywhere and that magnetic and electric fields have no possible influence at stellar, interstellar, galactic and intergalactic distances. Whether this assumption is true or not is difficult to gauge since we only have visual observations (at all sorts of frequencies) and cannot actually get out there to make the required measurements. So we have to fall back to what we think is reasonable and work from there.
- SiempreViernes 8y ago
  > The basic assumption of all gravity based theories and models is that the universe is electrically neutral everywhere and that magnetic and electric fields have no possible influence at stellar, interstellar, galactic and intergalactic distances This is impressively inaccurate: plasmas (charged and magnetic fluids) are basically the entirety of stellar evolution and the main part of everything up to galaxy evolution, so we have pretty good limits on the magnetic fields out in the universe. There is also direct measurements of magnetic fields integrated along the line of sight out to cosmological distances, and of course every spectra ever taken has measured the ionization level of the luminous gas.
  - oldandtired 8y ago
    I agree. Yet the models assume that gravity is the only influence for the motion of the galaxies, etc. We can see evidence of other phenomena but.... I have had this discussion with trained working physicists and the general reaction has been that these phenomena are completely insignificant in relation to stellar, interstellar, galactic and intergalactic motion. So where do we stand? If the orders of magnitude difference in strength between electric and magnetic fields and the strength of gravity is over 35. What kinds of effects do we expect with these kinds of differences? Especially when we are looking at plasmas and all sorts of ionisation. I don't know, but it does lead to intriguing questions.
- deleted 8y ago
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oldandtired 8y ago

The glass is testable though and would quickly be found. Dark matter and dark energy are assumed to exist with no experimental observations occurring. Every experiment has so far failed to show the existence of said entities. One possibility is that we do not have any way to find said entities with any means at our disposal. Another possibility is that they do not exist (just a figment of imagination) and that the theories requiring them are wrong. In that case, one should be looking for other theories that might be a more capable explanation. The question here is to determine when or whether we should stop looking for these entities and maybe move onto another model/theory. The basic assumption of all gravity based theories and models is that the universe is electrically neutral everywhere and that magnetic and electric fields have no possible influence at stellar, interstellar, galactic and intergalactic distances. Whether this assumption is true or not is difficult to gauge since we only have visual observations (at all sorts of frequencies) and cannot actually get out there to make the required measurements. So we have to fall back to what we think is reasonable and work from there.

SiempreViernes 8y ago
> The basic assumption of all gravity based theories and models is that the universe is electrically neutral everywhere and that magnetic and electric fields have no possible influence at stellar, interstellar, galactic and intergalactic distances This is impressively inaccurate: plasmas (charged and magnetic fluids) are basically the entirety of stellar evolution and the main part of everything up to galaxy evolution, so we have pretty good limits on the magnetic fields out in the universe. There is also direct measurements of magnetic fields integrated along the line of sight out to cosmological distances, and of course every spectra ever taken has measured the ionization level of the luminous gas.
- oldandtired 8y ago
  I agree. Yet the models assume that gravity is the only influence for the motion of the galaxies, etc. We can see evidence of other phenomena but.... I have had this discussion with trained working physicists and the general reaction has been that these phenomena are completely insignificant in relation to stellar, interstellar, galactic and intergalactic motion. So where do we stand? If the orders of magnitude difference in strength between electric and magnetic fields and the strength of gravity is over 35. What kinds of effects do we expect with these kinds of differences? Especially when we are looking at plasmas and all sorts of ionisation. I don't know, but it does lead to intriguing questions.
deleted 8y ago
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