Loop quantum gravity 01

[TheAenima86]

String theory... untestable, unfalsifiable, uncomfirmable... Sounds to me like a superstition. Certainly not a theory. Thank you for standing up to the string theorists. The sooner we let that *hypothesis* die, the sooner we can get back to real science...

[SpiderShane1]

this comment section is nerd-central

[CACBCCCU]

@SpiderShane1

Your comment looks like it's coming from the back-end of jackass central.

[CACBCCCU]

The thought I had that nuclear spin could decrease gravitational couplings between nuclei could relate to conditions much like in a cold neutron gas where the molecules are still randomly colliding, which I suppose can eliminate any frame-dragging based on consistent nuclear spin. Singular mass frame-dragging is a sort of amplification of gravitational impact and afaik, like every other GR effect, it is reproducible using a sufficient number of infinitesimal-energy infinite-wavelength gravitons.

[CACBCCCU]

My idea of incorporating an equal-opposite (matter retroreflectivity) rule in graviton actions mainly differs from GR in that GR's space, in the case of multiple masses, at the low-energy limit, is fundamentally the superposition of the individual effect of each mass. By this view, at the low energy limit, superposition of gravity wells won't work and what seems to be a form of gravitational entanglement emerges.

[CACBCCCU]

I should've left "might" out of the previous comment. It should be "Another reason, apparently also relating to dark matter and the quantum spin question mentioned with the previous one, involves closed/retroreflective graviton couplings." This drops the conventional presumption of areal flux uniformity, which is circular gravity-well symmetry, in favor of a nonuniform flux emphasizing equal-opposite graviton action. My understanding that is this can give a holographic character to matter.

[soulskies]

I have a serious question. Why we start with a continuous manifold with fixed dimension and require diffeomorphism invariance? By this way we give a topology to the space a priori. Can't we start with a set of points and consider all possible topologies? Can't we require invariance of physics under topology changes? Why is locality seen so important in contrast experimentally verified entanglement? Why we fix which point is a neighbor of which point from the very beginning? Thank you:)

[CACBCCCU]

@soulskies "I have a serious question."

Well that's exactly what 500 character youtube comments are for!

Which question?

[soulskies]

@CACBCCCU it is easy the see that there is only one question there: why do we give the space a manifold structure apriori? that's it. By this choice we can define tangent spaces, vectors, forms, tensor etc. However, dıfferentibility and continuity are very strong assumptions that may not by so natural and evident as it may seem. The time will show us whether the Einsteinian way of thinking is right or not.

[CACBCCCU]

@soulskies I don't know. Time dilation doesn't seem to be an experientially-realistic concept if pendula speed up in places where light clocks slow down. I think of that whenever the twins paradox is mentioned. One version has the traveler do all the frame-switching at one point, the turnaround on a dime, near lightspeed no less, and then goes on to explain that this is the step that's key to the traveler not aging as much... I really can't convey how stupid it seems in only 500 characters.

[CACBCCCU]

@soulskies I guess your issue(?) is with GR. Maybe I'm oversimplifying, but if gravity is gravitons then quantizing GR's spacetime makes no sense. The simplest reason for that is because light paths bend and graviton paths shouldn't. Another is that GR quantization implies a spin-2 quantum with no intrinsic quantum wavelength, which I don't think is realistic or matches what's seen out there. Another reason, also relating to dark matter, might involve closed/retroreflective graviton couplings.

[CACBCCCU]

Nuclei spin, though not always with much energy unless excited to do so. Extra spin would affect gravitational couplings between nuclei. I suppose it could reduce the couplings, while GR supposes it would increase them. Anyway, I see applying Newton's 3rd law (gravitational retroreflectivity in matter) as justifying closed loops in gravitational couplings, and despite the lack of anything I'd call extradimensional in any of ithat, it seems to me another way to describe the same thing as LQG.

[CACBCCCU]

The issue of dark matter is officially "off the deep end" with a lamestream media vengeance, it's as politicized as curved space. It's vital to general relativity, like Felix needs Oscar, it's more than about paying the rent.

[CACBCCCU]

Verlinde's interview in "Gravity doesn't exist" seems like the start of a public dialectic on the plusses and minuses of curved space, but maybe that's just my take. YT decided that cosmological-scale space appears, in observable effect, curvier than Einstein could've imagined, but getting to that required tossing out the idea of curved space in favor of gravitons with paths that don't curve. The idea gets scaled beyond typical galaxies in comments under "Macs J0025.4-1222 in 60 Seconds ..."

[CACBCCCU]

Going back to Euclid should be the "radical conceptual change in our concepts of space and time" he's talking about. "Going back to Euclid" is what I'd call taking gravitons seriously and so chucking the notion that just as light is curved (gravitational bending), space is curved. Suppose the ~100KLY (~10+21m) radius of Hoag's ring is set by multiplying proton radius by the E/G force-ratio between protons (~10-15m x ~10+36)=~10+21m. GR offers no clue about such cosmologically-quantized gravity.

[CACBCCCU]

Quantum gravity will never be compatible with General Relativity. It's sad that anyone even tries to make it work. Now people are trying to quantize space-time, all because someone with certain associations supposedly thought it was a great idea, in the modern age, to have actions lacking mediative quanta (aka curved space) and then politicize it. Could be the privileged class enjoys being obviously wrong, as it's another excuse to arbitrarily show their power.

[socratus1]

The formula of Gravity’s creation : h*f = kT logW 1 The formula E= h*f explained the energetic reason of Gravity 2 The formula E= kT logW explained the material reason of Gravity 3 This formula describes the possibility of realization of macro state from micro state. This formula explains the conditions of gravitation, the beginning conditions of star formation h*f = kT logW , h*f > kT logW , h*f < kT logW This local gravity area is Debye : Q(d) = h*f (max) / k

[aldebarankanon]

Thanks for the upload!

[bloodhive]

thanks for the upload

[iheartsteezeskiing]

5:34

[junior1984able]

String Theory Bitches!

[JarJar88forever]

Your thoughts make this real.

[CaptnHampton22]

ughhhhh

[visualkei72]

ohhhh.... what?

[smutery]

theory is cool, crappy video tho

[yourcommentsuck]

wtf is this guy talking about

[Calculusman08]

@yourcommentsuck If you don't know, go somewhere else haha.

[yourcommentsuck]

@Calculusman08 no,you....har har........I thought it was a miley vid

[Calculusman08]

@yourcommentsuck Miley? As in Miley Cyrus? haha you fail. Loop Quantum.... anything? Has nothing to do with her.

[Rob21091]

nice video though if he could only speak a bit more fluid would be better

[TheRavingRandomist]

@Rob21091 italian is very beautiful / because it is poor in phonems / if the italian ventures aboard / this advantage morphes into a disadvantage / same for the japanese btw / english is a hodge-podge language / a messy mess for many foreingners / italian/LATIN would be the better choice / for The De Facto Lingua Franca / so try to be clement towards the DeFectos / in CR's pronounciation ;-)

[nickharvey7]

Nice Video!

But could it be that Time has symmetry and geometry? Newton believed Time was a thing in itself and connected to motion and Einstein believed there was something missing from quantum mechanics. In my video The Paradox of Schrodingers Cat an artist view it is Time that is the Hidden Variable.

[NoSz4]

to much stuttering

[Brotramel]

@NoSz4 English is not his first language.

[gravytrain84]

He sounds like Latka, "Thank You Very Much". lmao

[minotarr]

Much better than string theory imao.

[matt247ryan]

set the whole thing wobbling on a five brane and project it out for a phd in string theory

[ninfan777]

How can anyone set throught this guys lecture. "discribe the uhh elementry uhh uhh degrees uhh of free-uhh-dom of a quantum uhh field uhh uhh theory when there is no uhh uhh background uhh uhh uhh space-time. " Don't get me wrong, I love learning about quantum gravity. But how can anyone learn from this guy I don't know.

[dkt80]

Thank you for posting this. Carlo Rovelli is a hero of mine :-)

[ExNihiloJimmy]

I love all this stuff

[usjaksri]

Rovelli ...the Best

[egroeg42]

string theory rulessssssssssssssssssssssssss­sss

[dmylwnas]

Follow the link provided by Steve to view the full video of the lecture. The quality is quite good too. Thank you Steve for this great upload!

[frippp66]

"The clarity is devastating, but where is the ambiguity? The ambiguity is in the cardboard box under the stairs." - Monty Python

[warthog212]

damn u steve i wanted to go to bed... ah well sleep can wait :)