Sabine Hossenfelder

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19h

FQXi - Foundational Questions Institute

fqxi.org

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No One Should Have Sole Authority to Launch a Nuclear Attack

scientificamerican.com

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New mineral discovered in Hekla volcano in Iceland

sciencenordic.com

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If The Universe Is Expanding, Then Why Aren't We?

forbes.com

Leszek Dziędziewicki: +Noah Friedman spacetime density? Where exactly this concept came from?
Presence of mass in spacetime affects geometry ( curvature ) of spacetime. In presence of mass path of moving object is the projection of a geodesic of the curved 4-D spacetime geometry onto 3-D space. That is what we describe as an effect of gravity.
Yes - two particles moving through space at same velocity ( that makes them at rest in relation to each other ) experience same elapsed time as long as gravity is same for both

Marco Pereira: Hi Sabine,

I read your posting about Bullet Galaxies. My theory provides another explanation for the Bullet Nature which makes it common and not the exception for very early Universe.

https://www.quora.com/If-you-had-an-endless-vertical-tunnel-that-had-no-air-in-it-and-a-black-hole-at-the-bottom-would-a-ball-fall-at-the-speed-of-light

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Here is the article:
http://www.worldscientificnews.com/wp-content/uploads/2017/07/WSN-82-2017-1-96-1.pdf

It rebuts General Relativity, 4D Spacetime, L-CDM, Inflation, Theory, Dark Matter, Dark Energy and show evidence of a Hyperspherical topology directly from the SDSS BOSS dataset.

Below is the map of the Current Universe
https://www.youtube.com/watch?v=ytuEctnD334

And below is the proposed Cosmogenesis (Big Pop and Many-Bangs Cosmogenesis).
https://www.youtube.com/watch?v=r54AQc2BR5c&t=6s

Below are selected postings:
hypergeometricaluniverse.quora.com - Selected Postings

Please feel free to ask questions or provide comments.

Matthew Rapaport: I'm unsure here if +Sabine Hossenfelder is saying we must separate space from time to grasp expansion of space or the other way around? They must be separable in some sense because the "flow of time" (metaphor) is constant everywhere. Why? Because the speed of light is constant everywhere (that at least is the assumption we all work with). A photon (moving at light speed through space) experiences (big metaphor) no time. As Andrew Thomas points out, everything in spacetime is moving at c. If you move slower in space, you move faster in time and vice versa. The total spacetime velocity is constant.

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Quantum tunneling takes time, new study shows

sciencenews.org

Matt McIrvin: This article leaves me more confused after reading it than I was beforehand. Are they asserting a violation of quantum mechanics? Are they asserting that the conventional theory violates relativity? (Schrödinger theory does, of course, but it wouldn't be the appropriate theory to use if the time scale is sufficiently short.)

Greg Roelofs: +Matt McIrvin My reading of it is that, despite having a wave function spread out across both the energetically allowed and forbidden regions (loosely speaking, at small radii and large radii, respectively), tunneling does not amount to the electron suddenly deciding that it's "more present" on the far side of the energy barrier, i.e., there's no instantaneous travel from small radii to large radii. The speed of light remains the speed limit even where quantum weirdness is involved.

(That's obviously a very fuzzy and simplified explanation; among other things, the wave function isn't static in time. And I might be entirely wrong in the other parts, too, so...grain of salt, eh? :-) )

Matt McIrvin: ...One of the things I remember puzzling about the hardest in relativistic quantum field theory was the relationship between causality and the single-particle propagator (the effect of a source that operates at one spot at a certain point in time). In classical theories it seems like one ought to restrict the other, but in QFT, not so much.

Even in relativistic theories, the propagator has support outside the light cone. What does that mean? Is the emitted particle traveling faster than light?

Feynman's one-sentence explanation was that you could have, say, virtual particle-antiparticle pairs spontaneously arising some distance away and the source happening to absorb the antiparticle, instead of creating a particle. So you end up with a particle that seems too far away to have been emitted. But it's hard to think about.

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Outraged about the Google diversity memo? I want you to think about it.
Chairs. [ Image: Verco ] That leaked internal memo from James Damore at Google ? The one that says one shouldn’t expect employees in all professions to reflect the demographics of the whole population? Well, that was a pretty dumb thing to write. But not be...

Outraged about the Google diversity memo? I want you to think about it.

backreaction.blogspot.com

Matthew Rapaport: This also about where (at Google facility) and when (company time) he wrote it. This at least as I understand it, perhaps I am wrong? Is a technical quibble but on his own time and equipment (personal blog, etc) is "free speech" on company time and equipment it is not

Filippo Salustri: +Travis Bird I would argue that some kind of progressive consequences would have been more reasonable. We (or at least I) don't know what, if anything, Google may have done about him in the past, so it's hard to know for sure what the actual situation is. On the premise that talking to people can significantly alter one's biases about those people, then I would hope they tried some kind of remediation first.

Filippo Salustri: Thanks Sabine for remaining calm and rational about this. You're absolutely right: no progress will be made on equity as long as the participants are, basically, screaming like children. You're also right that that change will happen slowly - too slow for some. But too fast for others. At least for now. Forcing change too quickly will likely cause even more trouble.
However, the rate of change isn't linear, and if constant gentle pressure is maintained, I suspect it will eventually cascade, and the rate of change will increase on its own.

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Self-tuning brings wireless power closer to reality
Cables under my desk. One of the unlikelier fights I picked while blogging was with an MIT group that aimed to wirelessly power devices – by tunneling: “If you bring another resonant object with the same frequency close enough to these tails then it turns o...

Self-tuning brings wireless power closer to reality

backreaction.blogspot.com

Olaf Fichtner: Oh dear, radio amateurs at MIT must be committing suicide out of embarrassment when they hear what people at their school propose.

This is something every radio amateur can quickly set up at home - and can equally quickly show that "energy leaves the 'system'".

This is embarrassing...

Matthew Rapaport: Ingenious paper indeed! But you are right that implementation will be too far off for your (otherwise worthy) Nobel prize :) Meanwhile I think we are already bathing in enough microwaves (cell towers) and magnetic resonance (high voltage A.C.) thank you! :)

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Math journal editors resign to start rival open-access journal

insidehighered.com

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New paper claims string theory can be tested with Bose-Einstein-Condensates
Fluorescence image of Bose-Einstein-Condensate. Image Credits: Stefan Kuhr and Immanuel Bloch, MPQ String theory is infamously detached from experiment. But in a new paper a group of Mexicans put forward a proposal to change that String theory phenomenology...

New paper claims string theory can be tested with Bose-Einstein-Condensates

backreaction.blogspot.com

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Penrose claims LIGO noise is evidence for Cyclic Cosmology
One man’s noise is another man’s signal. Noise is the physicists’ biggest enemy. Unless you are a theorist whose pet idea masquerades as noise. Then you are best friends with noise. Like Roger Penrose. Correlated "noise" in LIGO gravitational wave signals: ...

Penrose claims LIGO noise is evidence for Cyclic Cosmology

backreaction.blogspot.com

Andrés Santiago Pérez-Bergquist: Aperiodic tilings are really cool, but I stopped paying any attention to Roger Penrose after trying to read The Emperor's New Mind, which claims to prove AI is impossible but instead starts with the premise that AI is impossible because humans are special and goes down a rabbit hole of arguing that human consciousness is due to unknown quantum effects inside of microtubules, because there's no other known place it could be hiding, and never even presents an argument why that couldn't be replicated in a machine intelligence, too.

John Valentine: Drive-by comments:
1) Subtracting signals won't eliminate all the noise. Each detector could help eliminate more noise, but never everything.
2) "conformally invariant" would need the quantized stuff to decay into homogenous fields. That's not how I understand stuff works. Further, a paradox: there would need to be a fluctuation in that field, for there to be any further complexity arising as a new universe. This also needs a leap of faith about self-generating systems.
3) There's no harm in airing thought experiments, provided they are disclosed as such.

Matthew Rapaport: +Andrés Santiago Pérez-Bergquist Physicists love to speculate. But you are right. Even if Penrose is right about micro tubules (not saying he is) that would not mean the effect could not be duplicated any other way. I think there is a distinction to be made between AI and "artificial consciousness" but since you are both talking about the latter, your distinction is still a good one. But Penrose's physics speculations are more authoritative (he knows the math after all) than his speculations about philosophy of mind...

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