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C C
Sep 10, 2017 07:24 AM
(This post was last modified: Sep 10, 2017 07:29 AM by C C.)
https://www.wired.com/story/how-to-solve...n-physics/
EXCERPT: [...] Take a look at the complexity of reality around us. Traditionally, particle physicists explain nature using a handful of particles and their interactions. But condensed matter physicists ask: What about an everyday glass of water? Describing its surface ripples in terms of the motions of the roughly 10^24 individual water molecules—let alone their elementary particles—would be foolish. Instead of the impenetrable complexities at small scales (the “garbage”) faced by traditional particle physicists, condensed matter physicists use the emergent laws, the “beauty” of hydrodynamics and thermodynamics. In fact, when we take the number of molecules to infinity (the equivalent of maximal garbage from a reductionist point of view), these laws of nature become crisp mathematical statements.
While many scientists praise the phenomenally successful reductionist approach of the past centuries, John Wheeler, the influential Princeton University physicist whose work touched on topics from nuclear physics to black holes, expressed an interesting alternative. [...] Wheeler pointed out an important feature of emergent laws: Their approximate nature allows for a certain flexibility that can accommodate future evolution. In many ways, thermodynamics is the gold standard of an emergent law, describing the collective behavior of a large number of particles, irrespective of many microscopic details.
[...] Remarkably, modern insights about the most formidable challenge in theoretical physics—the push to develop a quantum theory of gravity—employ both the reductionist and emergent perspectives. Traditional approaches to quantum gravity, such as perturbative string theory, try to find a fully consistent microscopic description of all particles and forces. Such a “final theory” necessarily includes a theory of gravitons, the elementary particles of the gravitational field. For example, in string theory, the graviton is formed from a string that vibrates in a particular way. One of the early successes of string theory was a scheme to compute the behavior of such gravitons. However, this is only a partial answer. Einstein taught us that gravity has a much wider scope: It addresses the structure of space and time. In a quantum-mechanical description, space and time would lose their meaning at ultrashort distances and time scales, raising the question of what replaces those fundamental concepts....
MORE: https://www.wired.com/story/how-to-solve...n-physics/
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Zinjanthropos
Sep 10, 2017 12:21 PM
(This post was last modified: Sep 10, 2017 12:31 PM by Zinjanthropos.)
My questions CC to string theorists is why do the strings vibrate continuously(or do they) and/or what set them off in the first place? If string theory is correct then wouldn't that question need to be answered? If they have an idea, can you fill us in?
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C C
Sep 10, 2017 03:38 PM
(This post was last modified: Sep 10, 2017 03:45 PM by C C.)
(Sep 10, 2017 12:21 PM)Zinjanthropos Wrote: My questions CC to string theorists is why do the strings vibrate continuously(or do they) and/or what set them off in the first place? If string theory is correct then wouldn't that question need to be answered? If they have an idea, can you fill us in?
As Planck-scale entities with one dimension, having tension, and subject uncertainty-wise to always possessing some residual motion... Oscillation is thus part of their very nature. The lowest energy level of a string will still be non-zero and proportional to its tension, realizing itself as the "wriggling".
Even the most abstract concoctions of physicists (conceptual) usually if not always find themselves correspondingly depicted as something more intuitive extracted from human experience (i.e., spatial shape, alignment, change / action, etc).
CNRS: "Mathematics operates in two complementary ways. In the 'visual' one the meaning of a theorem is perceived instantly on a geometric figure. The 'written' one leans on language, on algebra; it operates in time." --A Theory Roughness - A conversation with Benoit Masdelbrot ... edge.org ... Dec 19, 2004
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Zinjanthropos
Sep 10, 2017 03:57 PM
(Sep 10, 2017 03:38 PM)C C Wrote: (Sep 10, 2017 12:21 PM)Zinjanthropos Wrote: My questions CC to string theorists is why do the strings vibrate continuously(or do they) and/or what set them off in the first place? If string theory is correct then wouldn't that question need to be answered? If they have an idea, can you fill us in?
As Planck-scale entities with one dimension, having tension, and subject uncertainty-wise to always possessing some residual motion... Oscillation is thus part of their very nature. The lowest energy level of a string will still be non-zero and proportional to its tension, realizing itself as the "wriggling".
Thanks CC. So I take it that the 'tension' varies from string to string or that there are only so many(tensions)?
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Secular Sanity
Sep 10, 2017 04:25 PM
(This post was last modified: Sep 10, 2017 04:27 PM by Secular Sanity.)
(Sep 10, 2017 03:57 PM)Zinjanthropos Wrote: So I take it that the 'tension' varies from string to string or that there are only so many(tensions)?
Different vibrational states of the same string would appear to be different types of particles. In string theories, strings vibrating at different frequencies constitute the multiple fundamental particles found in the current Standard Model of particle physics.
According to string theory, absolutely everything in the universe—all of the particles that make up matter and forces—is comprised of tiny vibrating fundamental strings. Moreover, every one of these strings is identical. The only difference between one string and another, whether it's a heavy particle that is part of an atom or a massless particle that carries light, is its resonant pattern, or how it vibrates.
Resonance in Strings
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C C
Sep 10, 2017 05:12 PM
(Sep 10, 2017 03:57 PM)Zinjanthropos Wrote: So I take it that the 'tension' varies from string to string or that there are only so many(tensions)?
I'm opportunistically putting this passage here purely to have it online. Note that it's in regard to what more or less might be considered the region of mainstream canon (which can be a multi-colored ball of yarn itself). Since there are also theories in superstring literature for tensionless strings (i.e., statements which can be made about strings that are universal are limited).
James E. Lidsey: The attractive feature of this picture is that it enables us to view all particles in terms of the same fundamental object -- the superstring. Although there are many different particles in the universe, the superstring theory tells us that they are all related to one another in a very fundamenal way. The characteristics of the superstring, such as tension and energy of vibration, can vary, and these variations manifest themselves as particles with different properties.
Another appealing feature of the supersring theory is that particle interactions are naturally explained by pieces of string splitting apart and joining together. For example, consider a particle decaying into two lighter particles. This can be viewed as a piece of string splitting into two smaller pieces. The reverse reaction, in which two particles combine, arises when two separate pieces of string meet and 'tie the knot'.
This picture of particles as strings is very appealing. We should emphasize, however, that the superstring concept is just a theory at this stage. Although it is a very compelling idea, there is no direct observational evidence to suggest that it is necessarily correct. --The Bigger Bang ... 2002
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Zinjanthropos
Sep 10, 2017 05:48 PM
(This post was last modified: Sep 10, 2017 05:50 PM by Zinjanthropos.)
(Sep 10, 2017 04:25 PM)Secular Sanity Wrote: (Sep 10, 2017 03:57 PM)Zinjanthropos Wrote: So I take it that the 'tension' varies from string to string or that there are only so many(tensions)?
Different vibrational states of the same string would appear to be different types of particles. In string theories, strings vibrating at different frequencies constitute the multiple fundamental particles found in the current Standard Model of particle physics.
According to string theory, absolutely everything in the universe—all of the particles that make up matter and forces—is comprised of tiny vibrating fundamental strings. Moreover, every one of these strings is identical. The only difference between one string and another, whether it's a heavy particle that is part of an atom or a massless particle that carries light, is its resonant pattern, or how it vibrates.
Resonance in Strings
I understood that much. Just wanted to know why they vibrated. Believe it or not I've read the Elegant Universe but obviously I may need to read it a few more times. Physics not my cup of tea but near the top of my favorite's list as far as most interesting goes.
Now if the matter in the universe is composed of vibrating strings then should there be a universal hum evident? If Earth was completely silent would there be a noticeable hum here since there are jillions of particles flying around at all times?
Also, wouldn't even the tiniest of vibrating particles create waves? If they do then what medium would these waves pass through? Are string waves the real deal or been detected? Is it possible that a vibrating string cannot produce a wave? I'm thinking strings must be able to because as matter they are also a wave? I take it that strings needs to pass through a field just to gain rest mass, no? I find this all too confusing at the moment. I need some serious straightening out on this.
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C C
Sep 11, 2017 03:56 PM
(This post was last modified: Sep 11, 2017 03:59 PM by C C.)
(Sep 10, 2017 05:48 PM)Zinjanthropos Wrote: Now if the matter in the universe is composed of vibrating strings then should there be a universal hum evident? If Earth was completely silent would there be a noticeable hum here since there are jillions of particles flying around at all times?
Also, wouldn't even the tiniest of vibrating particles create waves? If they do then what medium would these waves pass through? Are string waves the real deal or been detected? Is it possible that a vibrating string cannot produce a wave? I'm thinking strings must be able to because as matter they are also a wave? I take it that strings needs to pass through a field just to gain rest mass, no? I find this all too confusing at the moment. I need some serious straightening out on this.
Superstrings would be more basic than (or the origin of) the boson particles that mediate forces and serve as the quanta of fields. Their vibrations along with other dimensional factors would yield the appearance at our scale of the particles, atoms, and molecules of an atmosphere that carries sound. I.e., the result of the "hum" of a string would be a specific fermion or boson particle; even if the oscillations could magically be a sound, the latter would seemingly or potentially be too incredibly high for an organism to detect.
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Zinjanthropos
Sep 11, 2017 06:53 PM
(Sep 11, 2017 03:56 PM)C C Wrote: Superstrings would be more basic than (or the origin of) the boson particles that mediate forces and serve as the quanta of fields. Their vibrations along with other dimensional factors would yield the appearance at our scale of the particles, atoms, and molecules of an atmosphere that carries sound. I.e., the result of the "hum" of a string would be a specific fermion or boson particle; even if the oscillations could magically be a sound, the latter would seemingly or potentially be too incredibly high for an organism to detect.
Could this vibration of the strings that make up the particles have something to do with wave/particle duality?
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