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> The theory called asymptotically (as-em-TOT-ick-lee) safe gravity was proposed in 1978 by Steven Weinberg. Would a person interested in an article about quantum gravity not be familiar with the term asymptotically?
Earlier quoted context omitted.
This is how I pronounce it in IPA: /a.sim'to:.ti.kli:/ Why is TOT one syllable?
The weird thing about IPA is that the non-IPA pronunciation you’re replying to seems easier to understand.
I feel exactly the opposite way.
I wish people would use the IPA instead of their absurd ad-hoc systems. I learned IPA at school, and it has served me well.
All the pronunciation systems based on some other language are unreliable and idiosyncratic. And English, with its near-absence of reliable pronunciation/spelling rules, is particularly ill-suited.
Earlier quoted context omitted.
The 'non-kinetic' parts are just geometry, which we already understand and incorporate into general relativity.
Just as there is a huge difference between Maxwell's laws and QED -- the same gap lies with relativity and the graviton. Knowing the gravitational field as full fidelity partial differential equations based on the stress energy tensors is a great achievement. But it alone does not tell the full story as to how that field is mediated. Just as EM is mediated via virtual photons, we wish to know more..
Does it me any sense to say mass repels spacetime? So imagine a spring on the surface of a massive sphere. Imagine that you compress the spring and release it. The spring would compress outwards, the sphere not moving (especially if an another antipodean spring was set up with a compression release cycle occurring at the same time).
What if spacetime was like that spring, constantly being 'pushed' away or repelled from mass as it tries to return to an uncompressed state . The local effects would seemingly be the same, objects would travel the same curved paths through spacetime around the sphere as they would if mass was attractivly warping spacetime. Or perhaps we xould set up the conditions so that was so.
Maybe ive misunderstood, but in most depictions of gravity its a point like a bottom of a well that's sort of stretched the 'rubber sheet' of spacetime. I know it's just an analogy but almost all layman explanations show spacetime elongating as it moves closer to the mass, the elongation depicting the 'warping' of spacetime. It's possible the real maths tells a more accurate story, but to me the more correct mental picture would be to think of circles around the mass spaced at distances where crossing between them takes time=1. For the outside observer it seems time slows as you draw nearer the mass, that would suggest the circles become 'closer' or you'd cross more space per unit time. It would also suggest the outside observer would see you eventually slow to a stop but locally you continue to accelerate along the curved spacetime, so it doesn't seem to violate special relativity.
I'm not sure if mathematically space and time are treated separately, but if they're the same then thinking of mass as repelling spacetime 'outwards' from the surface of the mass seems to still work but might explain on larger scales where some of the expansion of space comes from - i.e. mass repels spacetime but the curvature this creates causes other mass to follow paths through spacetime that appear to make the two masses attract each other.
I get that im no doubt wrong but ive not seen anyone adress this possibility (probably because it wrong!) but id be interested to hear where it breaks down, as i dont see it!
> The theory called asymptotically (as-em-TOT-ick-lee) safe gravity was proposed in 1978 by Steven Weinberg. Would a person interested in an article about quantum gravity not be familiar with the term asymptotically?
> The theory called asymptotically (as-em-TOT-ick-lee) safe gravity was proposed in 1978 by Steven Weinberg. Would a person interested in an article about quantum gravity not be familiar with the term asymptotically?
This is the first time i see this word so I'm thankful.
I think it is relevant to consider gravity from a more abstract standpoint as well by looking at Le Sage's theory and particularly Hyugens' comments. [1] Whether gravity is mediated by a graviton, and the intricacies that QM brings to bear, one interesting idea I took from the above hundreds of years of thought on the subject -- gravity may be a pushing force mediated by constant spherical wave emission (quantized as…
There's no particular need for a special explanation of how particle exchange could produce an attractive force: as unlikely as it seems in classicical physics, it's how the forces (electromagnetic) arise in QED. The exchange of virtual photons can transport momentum any way you like.
Earlier quoted context omitted.
The weird thing about IPA is that the non-IPA pronunciation you’re replying to seems easier to understand.
Only to you. I feel exactly the opposite way. I wish people would use the IPA instead of their absurd ad-hoc systems. I learned IPA at school, and it has served me well. All the pronunciation systems based on some other language are unreliable and idiosyncratic. And English, with its near-absence of reliable pronunciation/spelling rules, is particularly ill-suited.
That's why people use their ad-hoc systems. Because many many many people don't know IPA. It's so far removed from English and uses so many letters that don't occur in English that it's close to being a completely different language.
The word "ɪn·tərˈnæʃ·ə·nəl" may make complete sense to someone who knows IPA but to to the many people who don't, it's complete gibberish.
Earlier quoted context omitted.
That bothered me as well (pronouncing rather than defining)
Particularly as the pronunciation is strange. Strange place to break syllables, and I'm not sure the second vowel is a 'e' in most pronunciations. /a-sim-TOT-i-klee/
Also, the theory is so intuitive and follows such a straightforward logical path from Quantum Mechanics and Relativity, that I would be incredibly surprised if it wasn't the theory closest to actual reality.
> The theory called asymptotically (as-em-TOT-ick-lee) safe gravity was proposed in 1978 by Steven Weinberg. Would a person interested in an article about quantum gravity not be familiar with the term asymptotically?