An alternative to the “ball on rubber sheet” model of gravity is “twisting a lump out of a sheet of silly putty.” You get the same curvature without relying on gravity to serve as a model of gravity (which always bothered me a bit)<p>For clarity, here’s what I mean: if you flatten out some silly putty (or pizza dough should work) then pinch and twist together some of the sheet into a lump, that pulls along the surrounding putty. So, if you drew lines on the putty then pulled it into lumps, you’d see the distortion to the lines.
It's too commonly argued Einstein didn't produce anything after GR. This article is a welcome correction. The same collaboration produced the EPR paradox - a real achievement which taught us a great deal about quantum theory.
I'm surprised Sabine doesn't mention the way fermions are treated in Loop Quantum Gravity [1][2]. My understanding is they are treated as "non-local" or open loops of gravitational force, and thus entry and exit points in space-time. This makes them conceptually similar to the "wormhole model" of matter that Einstein and Rosen originally described.<p>[1] <a href="https://arxiv.org/pdf/gr-qc/9404010" rel="nofollow">https://arxiv.org/pdf/gr-qc/9404010</a><p>[2] <a href="https://arxiv.org/pdf/1012.4719" rel="nofollow">https://arxiv.org/pdf/1012.4719</a>
Physicists didnt abandon this idea, Wheeler's geometrodynamics was all about the concept of geometry being relevant for more than grabity.<p>As it happens with so many cool ideas it did not germinate something useful.
If mass/energy were interconvertible with space, if the former were some curled form of the latter, could you explain dark energy as the uncurling of mass/energy into ordinary space?
As a physics student, I feel compelled to point out, to any readers who might now go read Hossenfelders other articles, that many of her views are generally not shared by a majority of physicists today.<p>She is a real physicist and not a kook, but she has been criticized for presenting her views (e.g. superdeterminism) as having much more acceptance than they actually do. She ignores and misrepresents counter-arguments regularly. Her ideas about, e.g. the explanatory power of entanglement wrt processions of moons around (IIRC) Jupiter are certainly well outside what I’d describe as regular astrophysics.<p>The golden standard of science communication was set by Sagan, and he always carefully pointed out when he was expressing a personal opinion, as opposed to one shared by the majority. Sabine Hossenfelder is no Sagan.<p>So proceed with caution. :)
An electron falling (electrostatically) toward a proton will reach the speed of light at some point. This is of course the same distance where inside it would need an escape velocity greater than c. So that's an event horizon due to a different force.<p>Some claim matter falling into a black hole never really does from the point of view of an outside observer. I've seen weird sounding descriptions like it "spreads out over the surface". What if electron orbitals are some kind of equivalent to that?<p>When I ask these (admittedly naive) questions, physicists will usually say something like "oh you have to treat that with quantum mechanics". But why? Isn't trying to resolve it using more conventional means (including concepts from relativity) a good idea? I feel like it's not right to reject one approach simply because nobody has figured out how to make it work while another does. That's different from showing that it can't work. Or have such approaches somehow been categorically proven inviable?
This recent presentation from Kepler Airospace claims that Einstein was on the right track and a goes even further, stating that gravity can be manipulated through EM. I've graduated in Physics but not quite sure what to make of it.<p><a href="https://www.researchgate.net/publication/383609891_Gravity_Modification_Experiment_Description_and_Results_presented_at_APEC_Propulsion_Conference_83124" rel="nofollow">https://www.researchgate.net/publication/383609891_Gravity_M...</a>
> Einstein finished his masterwork, the theory of general relativity, in 1915. He was 37 years old<p>Interestingly if you look at the most popular programming languages they were created by someone 37.5 years old, on average [0].<p>[0] <a href="https://pldb.io/blog/ageAtCreation.html" rel="nofollow">https://pldb.io/blog/ageAtCreation.html</a>
so, Higgs gives mass, and the mass curves the space to produce what the see as gravitation. I think there are some questions here to the Higgs at it seems it has some special relation to the spacetime.<p>And that
<a href="https://en.wikipedia.org/wiki/Black_hole_electron" rel="nofollow">https://en.wikipedia.org/wiki/Black_hole_electron</a><p>"...the angular momentum and charge of the electron are too large for a black hole of the electron's mass: a Kerr–Newman object with such a large angular momentum and charge would instead be "super-extremal", displaying a naked singularity, meaning a singularity not shielded by an event horizon."<p>And 2 singularities having worm-hole connection is the entanglement.
Einsteins later work led only recently to the following exciting conjecture:<p><a href="https://en.wikipedia.org/wiki/ER_%3D_EPR" rel="nofollow">https://en.wikipedia.org/wiki/ER_%3D_EPR</a><p>Unfortunately the author doesn't seem to know about this idea.
Well that’s very interesting because one of the latest ideas getting traction on solving the information paradox is exactly this — that black holes are connected to each other and the outside space by wormholes.<p>Check out the current Scientific American special publication.
naively, i'd wonder if the time properties of black holes could be used to effect local super-massive gravitational effects on entangled particles here.<p>e.g. they figured out how to entangle the electron and proton of a hydrogen atom with a complementary particle that is being pulled into a black hole, like if there were a way to entangle or entrain a local atom with hawking radiation from a black hole, where as the effect of entanglement, the local atom adopted the dialated time/gravity of its remote counterpart in the black hole. the effect would be that states of matter which only existed on the ephemeral femtosecond scale here would be stabilizied for longer time periods because its "clock" had been slowed down by its adopted clock entanglement via hawking radiation in a kind of black-hole-time.<p>maybe better for a movie script or fiction, but people who think of these things reason them through logically before doing the math as well.
Nothing has satisfied me between why gravity and magnetism are not the same thing. A ferrous material where the electron poles can be aligned show high forces. Most things are totally misaligned, which I believe creates gravity. No explanation on stackexchange or anything else convinces me. Most of the arguments feel egotistical to me.