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Why string theory persists — despite the knotty physics

rod

Oct 22, 2019
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String theory is a powerful idea, unfinished and untested, but one that has persisted for decades despite inauspicious beginnings.

Why string theory persists — despite the knotty physics : Read more
I enjoyed reading this report. A note here from what was said "And as for string theory, it mostly faded into the background. It would be revived in the 1970s, once theorists realized that it could describe more than the strong force and after they found a way to get rid of the tachyon predictions in the theory. The theory still needed extra dimensions, but physicists were able to reduce the number to a more reasonable-sounding 10. And with the realization that those dimensions could be tiny and curled up below the scale at which we could directly observe it, string theory didn't seem to wacky after all. And today, that string theory also remains, still attempting to explain the strong force — and so much more."

My note, here we see 10 extra dimensions vs. the 4 in Special Relativity that was discussed. However, there is another recent report on string theory that shows there could be 1E+200 extra dimensions, The Universe May Be Flooded with a Cobweb Network of Invisible Strings

This report concerned axions.
 
Dec 28, 2019
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It also required the existence of particles that travel faster than the speed of light, called tachyons. That was a major problem for early string theory, since tachyons don't exist, and if they did they would flagrantly violate the incredibly successful special theory of relativity. -- Quote from article

Actually, tachyons don't violate Special Relativity (exactly). Special Relativity only says that nothing with mass can travel AT the speed of light because mass increases with speed and becomes infinite at the speed of light. But the only thing possibly preventing objects with mass from traveling faster than light (once they somehow get to such a speed) is the fact that mass then becomes mathematically imaginary. And whether "imaginary mass" is physically possible or not is a whole different question. It's hard to know what it would be like or even measurable. But tachyons (if they exist) would have imaginary mass, which could account for why they've never been detected. This might also be a case where the ordinary sense of "imaginary" and the mathematical sense of "imaginary" (square root of a negative number) combine!...
 
Jan 15, 2020
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If ya gimmee six or eight extra dimensions for wiggle room, and everybody promises to never ever look at them....I could also be a smart SOB....
 
Jan 15, 2020
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It also required the existence of particles that travel faster than the speed of light, called tachyons. That was a major problem for early string theory, since tachyons don't exist, and if they did they would flagrantly violate the incredibly successful special theory of relativity. -- Quote from article

Actually, tachyons don't violate Special Relativity (exactly). Special Relativity only says that nothing with mass can travel AT the speed of light because mass increases with speed and becomes infinite at the speed of light. But the only thing possibly preventing objects with mass from traveling faster than light (once they somehow get to such a speed) is the fact that mass then becomes mathematically imaginary. And whether "imaginary mass" is physically possible or not is a whole different question. It's hard to know what it would be like or even measurable. But tachyons (if they exist) would have imaginary mass, which could account for why they've never been detected. This might also be a case where the ordinary sense of "imaginary" and the mathematical sense of "imaginary" (square root of a negative number) combine!...
The question of the speed of light as being a limiting speed could be opened.
The decision by BIPM (Bureau international des Poids et des Mesures) to make it a constant of nature might be a little premature.
It has not been measured everywhere in outer space.
Forcing the speed of light to be a constant of nature might introduce unnecessary hardships on
space geometry modelling.
The problem is that nobody is going to measure the speed of light anymore since it is being declared
a constant.
If it is not really a universal constant then it introduces all sorts of complication in experimental and theoretical physics.
 
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