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Black holes do not exist where space and time do not exist, says new theory

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Re: Black holes do not exist where space and time do not exist, says new theory

#31

Post by Steuard »

PaulHoule wrote: post #27

As a physics PhD I feel like an idiot for accepting the theory of the classical black hole. If you write the equations for the space around a black hole in the straightforward way you see a singularity at the event horizon. You can make a coordinate change that makes this singularity go away, but then you get the classical black hole singularity where there is either an "end of time" or an infinitely dense point or r…

Counterargument to "the Planck scale is blown up to be visible": The expanding universe itself has (or very probably has) stretched by a factor starting to push into "practical infinity" territory since the Big Bang. (As I recall, common models of cosmic inflation require a minimum of 60 "e-foldings" of expansion in the first moments of the universe's existence: a factor of 10^26 or so, not counting the considerable expansion since then.) By that argument, we ought to be dangerously close to "voiding the warranty" on spacetime already, everywhere in the universe.

As far as I know, the notion that curved space can "enlarge the Planck-scale granularity of spacetime" is not a universal feature of quantum gravity theories. It's not even clear to me what that would mean. (I've only seen one or two string theory talks that suggested such a thing, for instance, and most of the experts in the audience seemed fairly convinced that the idea had no compelling basis in our context. I don't recall whether that's a feature of LQG.)

Re: Black holes do not exist where space and time do not exist, says new theory

#32

Post by [deleted] »

PaulHoule wrote: post #27

As a physics PhD I feel like an idiot for accepting the theory of the classical black hole. If you write the equations for the space around a black hole in the straightforward way you see a singularity at the event horizon. You can make a coordinate change that makes this singularity go away, but then you get the classical black hole singularity where there is either an "end of time" or an infinitely dense point or r…

[deleted]

Re: Black holes do not exist where space and time do not exist, says new theory

#34

Post by fargolime »

PaulHoule wrote: post #27

As a physics PhD I feel like an idiot for accepting the theory of the classical black hole. If you write the equations for the space around a black hole in the straightforward way you see a singularity at the event horizon. You can make a coordinate change that makes this singularity go away, but then you get the classical black hole singularity where there is either an "end of time" or an infinitely dense point or r…

As not a physics PhD it seems so much easier to realize that GR's equivalence principle fails at the event horizon, in which case black holes are a mistake of GR. (Let downvotes commence since I must be a crackpot.)

Let a particle be above the horizon and escaping to infinity, as GR allows. By definition of a black hole, a signal can't be sent from below the horizon to the escaping particle. In an inertial frame, signals can be sent between any two points in the frame. Then an inertial frame relative to which the escaping particle is at rest can't extend below the horizon. That's a violation of the equivalence principle, because (we'll call this law of physics K:) inertial frames can wholly contain other inertial frames, and the inner frames can be extended to fill all of the outer frame. But as we've proven, a frame falling through the horizon of a black hole violates law K. An inertial frame relative to which the escaping particle is at rest cannot be extended to fill all of a frame falling through the horizon. Texts on GR tell us that an inertial frame can fall through the horizon, but we've just proven that such frame cannot be inertial without violating the equivalence principle. That principle is the core of GR, so black holes need be rejected as a mistake of the theory.

Black holes are predicted by the Schwarzschild metric. That metric can be tweaked to not predict black holes, while still agreeing with all physical experiments of Schwarzschild geometry to date. In the tweaked metric the escape velocity is always less than the speed of light (including at r Please downvote this major advance of physics if you haven't already.

Re: Black holes do not exist where space and time do not exist, says new theory

#35

Post by Retric »

mrfusion wrote: post #28
filearts wrote: post #3

"In gravity's rainbow, space does not exist below a certain minimum length, and time does not exist below a certain minimum time interval" Does this imply that neither space nor time can go below the given threshold independently? I.e.: could a situation be imagined where time remains above the minimal interval, but space is below? Also, would those answers be different depending on the observer's time / position?

So does discrete space and time also solve zenos paradox? (or was that already solved classically?)

Yes.

But Zenos paradox has a simple solution; Time. It takes k(1) * 1/x time to reach k(2) * 1/x location assuming constant velocity. Basically moving an infinitely small distance takes an infinitely small unit of time.

Re: Black holes do not exist where space and time do not exist, says new theory

#36

Post by TheLoneWolfling »

fargolime wrote: post #34
PaulHoule wrote: post #27

As a physics PhD I feel like an idiot for accepting the theory of the classical black hole. If you write the equations for the space around a black hole in the straightforward way you see a singularity at the event horizon. You can make a coordinate change that makes this singularity go away, but then you get the classical black hole singularity where there is either an "end of time" or an infinitely dense point or r…

As not a physics PhD it seems so much easier to realize that GR's equivalence principle fails at the event horizon, in which case black holes are a mistake of GR. (Let downvotes commence since I must be a crackpot.) Let a particle be above the horizon and escaping to infinity, as GR allows. By definition of a black hole, a signal can't be sent from below the horizon to the escaping particle. In an inertial frame, sig…

Elaborate on said "tweak" to the Schwarzschild metric?

Re: Black holes do not exist where space and time do not exist, says new theory

#37

Post by fargolime »

TheLoneWolfling wrote: post #36
fargolime wrote: post #34

Earlier quoted context omitted.

As not a physics PhD it seems so much easier to realize that GR's equivalence principle fails at the event horizon, in which case black holes are a mistake of GR. (Let downvotes commence since I must be a crackpot.) Let a particle be above the horizon and escaping to infinity, as GR allows. By definition of a black hole, a signal can't be sent from below the horizon to the escaping particle. In an inertial frame, sig…

Elaborate on said "tweak" to the Schwarzschild metric?

See https://finbot.wordpress.com/2010/01/02/toward-a-new-theory/. It's not my blog.

Re: Black holes do not exist where space and time do not exist, says new theory

#38

Post by antognini »

fargolime wrote: post #34
PaulHoule wrote: post #27

As a physics PhD I feel like an idiot for accepting the theory of the classical black hole. If you write the equations for the space around a black hole in the straightforward way you see a singularity at the event horizon. You can make a coordinate change that makes this singularity go away, but then you get the classical black hole singularity where there is either an "end of time" or an infinitely dense point or r…

As not a physics PhD it seems so much easier to realize that GR's equivalence principle fails at the event horizon, in which case black holes are a mistake of GR. (Let downvotes commence since I must be a crackpot.) Let a particle be above the horizon and escaping to infinity, as GR allows. By definition of a black hole, a signal can't be sent from below the horizon to the escaping particle. In an inertial frame, sig…

I don't completely understand the argument you're making, so please correct me if I'm misunderstanding you, but I think I see the problem.

It is true that in an inertial frame you can send a signal between two points. But if you have an inertial frame which is falling into a black hole any signal sent from beneath the event horizon will not reach any other point until that point has also fallen beneath the event horizon.

Remember that the inertial frame is in free fall, so points which are fixed in the inertial frame are moving according to a distant observer.

Re: Black holes do not exist where space and time do not exist, says new theory

#39

Post by fargolime »

antognini wrote: post #38
fargolime wrote: post #34

Earlier quoted context omitted.

As not a physics PhD it seems so much easier to realize that GR's equivalence principle fails at the event horizon, in which case black holes are a mistake of GR. (Let downvotes commence since I must be a crackpot.) Let a particle be above the horizon and escaping to infinity, as GR allows. By definition of a black hole, a signal can't be sent from below the horizon to the escaping particle. In an inertial frame, sig…

I don't completely understand the argument you're making, so please correct me if I'm misunderstanding you, but I think I see the problem. It is true that in an inertial frame you can send a signal between two points. But if you have an inertial frame which is falling into a black hole any signal sent from beneath the event horizon will not reach any other point until that point has also fallen beneath the event hori…

> But if you have an inertial frame which is falling into a black hole any signal sent from beneath the event horizon will not reach any other point until that point has also fallen beneath the event horizon.

Problem is, the escaping particle never falls beneath the horizon. So an inertial frame in which that particle is at rest cannot extend below the horizon at all. That's a violation of law K for a frame falling into a black hole. By violating law K, the latter frame cannot be inertial. Note that law K is about allowing inner frames be extended to fill all of an outer frame.

Let a cloud of particles straddle the horizon. Let all the particles above the horizon be escaping to infinity. According to GR, such cloud must be splitting apart. The particles below the horizon must move inexorably inward, toward the singularity at the center of the black hole, whilst the particles above the horizon move ever outward, away from the black hole. Then a frame falling through the horizon of a black hole cannot be inertial, for in an inertial frame the cloud needn't be splitting apart (since law K applies). For example, in an inertial frame in Earth's atmosphere you can have a cloud of particles in which half the particles are given to be escaping to infinity, and the cloud needn't be splitting apart (just let all the particles escape in formation).

Re: Black holes do not exist where space and time do not exist, says new theory

#40

Post by 0942v8653 »

Florin_Andrei wrote: post #30
RickHull wrote: post #14

Where is it that space does not exist? The headline seems like a contradiction in terms.

Your question, actually, is self-contradictory. "Where" already assumes space.

I believe that was the point. The article title makes the same mistake.
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