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Einstein's Other Theory of Everything

nautil.us

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Re: Einstein's Other Theory of Everything

#91

Post by pdonis »

greysphere wrote: post #49
sigmoid10 wrote: post #37

Earlier quoted context omitted.

You can plug arbitrary values in, but you can not expect to gain any valid predictions or reasonable physical insight from Coulomb's law as soon as you are no longer dealing with static point charges. That's because B and E are not independent quantities but actually closely intertwined components of the electromagnetic field strength Tensor F. As soon as you start dealing with motion, these components will mix, pres…

In a classical view of 2 particles accelerating towards each other v x r will always be 0 so B will always be 0 even if the particles are accelerating towards each other. I believe all this holds under QFT [1]. Looking further a redefinition E is necessary when including the \beta factor [2]. So that was a mistake on my part - relativity does change the rhs of Coulomb's law. Admittedly the problem as stated (two part…

> In a classical view of 2 particles accelerating towards each other v x r will always be 0

Only if the impact parameter is exactly zero. But that is an extremely unlikely edge case.

Re: Einstein's Other Theory of Everything

#92

Post by pdonis »

tgarrett wrote: post #73
greysphere wrote: post #33

Earlier quoted context omitted.

> You can't just plug numbers into Coulomb's Law for this case, because Coulomb's Law by itself is not relativistically correct. Sorry if this is a bit pedantic, but as someone trying to study this at the moment, I don't see this the same way and I'd like to validate my interpretation: You can just plug numbers into Coulomb's law, that part is correct. But then the problem of infinite velocities comes from interpreti…

Hi greysphere, you are definitely correct that one primary thing preventing velocity of the electron from exceeding than the speed of light is the presence of gamma in the relativistic force law, aka \partial_t (m_e \gamma v ) = q_e(E + v \times B), although the LHS doesn't quite equal \gamma m_e a, since \gamma also depends on v... In general I think it's fine to use Coulomb's law as an approximation in this case be…

> so the electron is now bound to the proton

This is extremely unlikely unless the relative motion is very slow, or, to put it another way, the total center of mass energy is very close to the rest energy of electron + proton, so there is a significant probability amplitude for capture into a bound hydrogen atom.

The post I originally responded to was obviously not considering such a case since it claimed the electron could exceed the speed of light.

Re: Einstein's Other Theory of Everything

#93

Post by doug-moen »

frede wrote: post #84

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. https://www.researchgate.net/publication/383609891_Gravity_M...

I'm cheering them on, but I'm not confident that the technology works, based on the people involved. I don't think the new physics underlying this work are published in a peer-reviewed physics journal.

Here's a page about John Brandenburg, one of the authors: https://rationalwiki.org/wiki/John_Brandenburg>

Re: Einstein's Other Theory of Everything

#94

Post by oneshtein »

cyberax wrote: post #28
raattgift wrote: post #15

Earlier quoted context omitted.

The "balls on a rubber sheet" is a pain because nothing is in free-fall: there are dissipative contact forces between the balls and the rubber sheet. Consequently realistic initial [position, velocity] values for the test ball cannot give you a stable circular orbit around the central mass ball. Venus isn't about to fall into the sun. Now try setting up Earth-Moon or the Jovian-Gallilean systems on the rubber sheet.…

> The "balls on a rubber sheet" is a pain because nothing is in free-fall The balls on a rubber sheet model is actually really great, but not in the way it's typically presented (rolling a ball down the curvature). Instead, just use a pen to draw lines to show the concept of geodesics. Start like this: 1. Imagine that you can move without friction if you stay at the same vertical level. 2. Draw a line on a flat rubbe…

Same level relative to what? This model of gravity requires gravity to work.

Re: Einstein's Other Theory of Everything

#95

Post by oneshtein »

carapace wrote: post #82
photonthug wrote: post #66

Earlier quoted context omitted.

As a sibling points out, it’s not explanatory as much as a visualization. Or if it explains something it’s not gravity itself but a less familiar kind of geometry and a new concept of straightness where sometimes the shortest path is what we’d usually think of as curved. Seems fine. Little chance of understanding gravity until you can grasp the prerequisite concepts you’re going to describe it with. And anyway explai…

Gravity is one of the fundamental forces, there's no recursion in it's definition, indeed we don't "define" it we describe it. The actual description of gravity isn't hard to understand, it's just really strange. There is no good reason to introduce confusing and intrinsically incorrect models.

> Gravity is one of the fundamental forces

until we crack it.

Re: Einstein's Other Theory of Everything

#96

Post by NooneAtAll3 »

wruza wrote: post #83
bmitc wrote: post #60

Earlier quoted context omitted.

It's not trying to explain gravity. It's trying to visualize it.

I think it’s a good model because it poses the same question: an object is in a field gradient of otherwise forceless space, so what ? In 0g a mass on a rubber sheet won’t attract an object, so why would real gravity “lines” attract an object that doesn’t try to move across it? There’s no supergravity for “gravity sheet” to work either. Afaiu, the answer is that moving through time in a gravitational gradient makes y…

in 0g, object that does not leave contact with the curved (by-whatever-means) rubber sheet will behave the same way

"using gravity" in the experiment is convenience of the experiment - gravity is freely abundant to use, both as a source of curvature and source of "making objects not leave the sheet"

if you want to hold the sheet by yourself, and hold the objects to the sheet by yourself - you are free to do it, enjoying your victory of "not using gravity"

but the point is not in the means, but in the end - create curvature, keep contact

Re: Einstein's Other Theory of Everything

#97

Post by XorNot »

pdonis wrote: post #89
XorNot wrote: post #35

Earlier quoted context omitted.

You can't just reject evidence like this though: electrons orbiting protons don't emit synchrotron radiation. So whatever else you want to the prize, you have to be able to reproduce this result.

> electrons orbiting protons don't emit synchrotron radiation Not in atoms, no. But I mentioned scattering, which is a different scenario.

And I have absolutely no idea what you think this explains. Which is the point of physics you know: to convey actionable concepts about the behavior of experiments. Not be cryptic and vague.

Re: Einstein's Other Theory of Everything

#98

Post by bmitc »

breck wrote: post #86
bmitc wrote: post #62

Earlier quoted context omitted.

That's not a great comparison. Einstein had already turned physics on its head and kickstarted several foundational paradigms in 1905, when he was only 25-26 years old.

Fair enough. I think Linus might be a good comparison. Linux in his 20's, which turned world on its had, but it masterpiece Git at age ~36.

I don't fetishize physicists by any means, but Linux and Git are nerdy pursuits that caught on somehow, mainly as a revolt against paid software. Git is pretty bad at times, terrible UX, tons of edge cases, and treats the world as if its made from text.

Einstein set forth some of the most foundational and tested theories ever.

Re: Einstein's Other Theory of Everything

#99

Post by XorNot »

IAmGraydon wrote: post #32
tux3 wrote: post #26

Earlier quoted context omitted.

A problem with trying to use concepts like this and asking "what if?" is that it's reasonning and trying to extrapolate from an analogy It's one thing to use analogies to guide your intuition, but physical theories are written in the language of math, and not the language of analogies! You don't have to use QM to describe protons and electrons at a fine level, but it is very hard to do otherwise, because whatever new…

Well said. I think Einstein himself used the same kind of analogous thinking to guide his intuition, and wouldn’t have been nearly as successful as he was without allowing himself this sort of unbounded thinking. In the end, however, he proved these intuitions true or false with the light of math.

Einstein followed where the results lead - his primary breakthrough was assuming no wave-propagation medium was necessary, and accepting an absurd result on it's face by exploring the mathematical consequence (namely: speed of light is constant, as a result the passage of time can vary, there is no medium through which light propagates unlike all other known wave phenomena).

You have grown up with a set of different analogies based on more modern theories: which is to say, you're letting the tail wag the dog: we have those analogies to explain physics to laymen, but the analogies don't inform the physics.

Re: Einstein's Other Theory of Everything

#100

Post by oneshtein »

cyberax wrote: post #18
phkahler wrote: post #17

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. 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…

> An electron falling (electrostatically) toward a proton will reach the speed of light at some point. Only in Newton's mechanics. With special relativity, it'll approach the lightspeed. > 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". It doesn't. To an outside observer, the obje…

Even in Newton's mechanic, electron cannot accelerate further after reaching speed of light propagation in the medium. When electron exceeds speed of light it a medium (because of change in medium, for example), it produces Cherenkov radiation.
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