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There is another possible explanation instead of dark matter and that is electric charge and currents (plasma flows). Electric force is many orders of magnitud

There is another possible explanation instead of dark matter and that is electric charge and currents (plasma flows). Electric force is many orders of magnitude stronger than gravity. So, if the objects in the universe are charged, the repelling force between them could account for the expansion acceleration in a very simple way.

simonh 10y ago
Except that electrical/magnetic forces are vastly more powerful than gravitational forces. Any such force that's noticeable at the cosmic scale would be powerful enough at the object scale (star, planet, even galaxy) to tear them apart or cause them to collapse. Lets suppose the Earth and the Sun were both positively charged sufficiently that their repulsive force was enough to noticeably affect the orbit of the Earth. For that to be true, the repulsive forces due to the positive charge on earth itself would have to be so great that it would blast the planet to fragments.
- davrosthedalek 10y ago
  I don't think this is true. Let's assume every matter is our solar system is actually not neutral, but slightly positively charged. For Sun-Earth, let's say this reduces the effective force by 1%. Since both Coulomb and gravitational attraction has the same power law, this fixes the change everywhere, or in other words, you could absorb the change into the gravitational constant. Same goes for making everything 1% less dense.
  - adekok 10y ago
    That's not how physics works. We've measured the charge of base particles, we know their charge to 8 decimal places. (e.g. for electrons). There is simply no way for the force of electromagnetism to be different at the scale of solar systems. Even MOND is a tiny modification to Newtons laws, and only a modification in extreme circumstances.
    - davrosthedalek 10y ago
      I think you misunderstood my post. My parent post argued that a mass-proportional charge imbalance big enough to cause a measurable change in gravitation would have catastrophic consequences for planets. Indeed, this is not true, the effects on the planet are of the same scale, i.e. ridiculously small. Of course, as I wrote, both laws follow the same power-law, so this can not solve the dark matter problem. Indeed you can absorb it in the gravitational constant. I also did not suggest that electromagnetism should be different at the scale of solar systems. A test of the charge equivalence of protons and electrons to 8 digits is by far not good enough to rule this out. You have to probe the proton charge to ~1E-20 for a 1% change of the gravitational effect. This is beyond the reach even for atomic level measurements. More interesting are the bounds on charge conservation.
drjesusphd 10y ago
Dark matter is not the same as dark energy.
- vorg 10y ago
  Dark matter did include dark energy for a while, according to the article... > starting from the 1980s, the new cosmological dogma was that dark matter constituted a staggering 95 percent of all matter in the universe. That lasted, well, right until the bomb hit us in 1998. It turned out that the expansion of the universe is accelerating, not decelerating like all of us originally thought. Any form of genuine matter, dark or not, should have slowed down acceleration. And so a whole new type of entity was invented: Dark energy. Now the accepted cosmology is that the universe is made up of 70 percent dark energy, 25 percent dark matter, and 5 percent regular matter. But dark energy is just a quick fix, the same as dark matter is. That makes it sound like dark energy is an offshoot of dark matter, a different type of dark matter that explains an accelerating expansion instead of the extra gravitational effects.
adekok 10y ago
> the repelling force between them could account for the expansion acceleration in a very simple way. The electromagnetic force still follows the inverse square law. So if objects in the universe are charged, the effects end up being similar to the force of gravity. i.e. it's still an inverse square law, and it's still linearly related to the observable mass. The only way something else is happening is if you use either the dark matter / energy theories, or MOND. The shorter explanation is that it's naive to think that "off the cuff" ideas from amateurs are better than ideas from experts in the field who have devoted decades of their life to the subject.
SagelyGuru 10y ago
Anyway, thank you for the predictable downvotes. At least I know how Galileo felt when downvoted for his non-standard explanation. "And still it turns!" I am afraid that I remain similarly unconvinced by appeals to the authority of the "experts in the field". At least "the experts" in Galileo's days did not keep inventing new invisible things, except for the angels on the point of a needle. This made their theory more stable and, some may say, more credible, than dark matter.

simonh 10y ago

Except that electrical/magnetic forces are vastly more powerful than gravitational forces. Any such force that's noticeable at the cosmic scale would be powerful enough at the object scale (star, planet, even galaxy) to tear them apart or cause them to collapse. Lets suppose the Earth and the Sun were both positively charged sufficiently that their repulsive force was enough to noticeably affect the orbit of the Earth. For that to be true, the repulsive forces due to the positive charge on earth itself would have to be so great that it would blast the planet to fragments.

davrosthedalek 10y ago
I don't think this is true. Let's assume every matter is our solar system is actually not neutral, but slightly positively charged. For Sun-Earth, let's say this reduces the effective force by 1%. Since both Coulomb and gravitational attraction has the same power law, this fixes the change everywhere, or in other words, you could absorb the change into the gravitational constant. Same goes for making everything 1% less dense.
- adekok 10y ago
  That's not how physics works. We've measured the charge of base particles, we know their charge to 8 decimal places. (e.g. for electrons). There is simply no way for the force of electromagnetism to be different at the scale of solar systems. Even MOND is a tiny modification to Newtons laws, and only a modification in extreme circumstances.
  - davrosthedalek 10y ago
    I think you misunderstood my post. My parent post argued that a mass-proportional charge imbalance big enough to cause a measurable change in gravitation would have catastrophic consequences for planets. Indeed, this is not true, the effects on the planet are of the same scale, i.e. ridiculously small. Of course, as I wrote, both laws follow the same power-law, so this can not solve the dark matter problem. Indeed you can absorb it in the gravitational constant. I also did not suggest that electromagnetism should be different at the scale of solar systems. A test of the charge equivalence of protons and electrons to 8 digits is by far not good enough to rule this out. You have to probe the proton charge to ~1E-20 for a 1% change of the gravitational effect. This is beyond the reach even for atomic level measurements. More interesting are the bounds on charge conservation.

drjesusphd 10y ago

Dark matter is not the same as dark energy.

vorg 10y ago
Dark matter did include dark energy for a while, according to the article... > starting from the 1980s, the new cosmological dogma was that dark matter constituted a staggering 95 percent of all matter in the universe. That lasted, well, right until the bomb hit us in 1998. It turned out that the expansion of the universe is accelerating, not decelerating like all of us originally thought. Any form of genuine matter, dark or not, should have slowed down acceleration. And so a whole new type of entity was invented: Dark energy. Now the accepted cosmology is that the universe is made up of 70 percent dark energy, 25 percent dark matter, and 5 percent regular matter. But dark energy is just a quick fix, the same as dark matter is. That makes it sound like dark energy is an offshoot of dark matter, a different type of dark matter that explains an accelerating expansion instead of the extra gravitational effects.

adekok 10y ago

> the repelling force between them could account for the expansion acceleration in a very simple way. The electromagnetic force still follows the inverse square law. So if objects in the universe are charged, the effects end up being similar to the force of gravity. i.e. it's still an inverse square law, and it's still linearly related to the observable mass. The only way something else is happening is if you use either the dark matter / energy theories, or MOND. The shorter explanation is that it's naive to think that "off the cuff" ideas from amateurs are better than ideas from experts in the field who have devoted decades of their life to the subject.

SagelyGuru 10y ago

Anyway, thank you for the predictable downvotes. At least I know how Galileo felt when downvoted for his non-standard explanation. "And still it turns!" I am afraid that I remain similarly unconvinced by appeals to the authority of the "experts in the field". At least "the experts" in Galileo's days did not keep inventing new invisible things, except for the angels on the point of a needle. This made their theory more stable and, some may say, more credible, than dark matter.