Stephen Hawking theorizes solution to black hole information paradox

[gary]

Rachel Feltman, in a article in today's Washington Post, reports on a new theory on black holes presented by Stephen Hawking at the
KTH Royal Institute in Stockholm.

Originally Posted by Rachel Feltman, Washington Post, August 25th 2015

On Tuesday, he explained his new theory: "I propose that the information is stored not in the interior of the black hole as one might expect, but in its boundary, the event horizon," Hawking said. The event horizon is the sort of shell around a black hole, past which all matter will be drawn into the dense object's powerful embrace.

According to Hawking's idea, the particles that enter a black hole leave traces of their information on the event horizon. When particles come back out — in a phenomenon called Hawking Radiation — they carry some of that information back out, preserving it. Technically, anyway.

"The information is stored in a super translation of the horizon that the ingoing particles [from the source star] cause," he explained, for those of you who like a little more physics lingo. "The information about ingoing particles is returned, but in a chaotic and useless form. For all practical purposes the info is lost."

At Monday's public lecture, he explained this jumbled return of information was like burning an encyclopedia: You wouldn't technically lose any information if you kept all of the ashes in one place, but you'd have a hard time looking up the capital of Minnesota.

Article here -
http://www.washingtonpost.com/news/s...t-black-holes/

[AlexN]

Thanks Gary.

[xelasnave]

Thanks Gary.
I wonder if he speculating to entertain or if he has a theory.
The reporter mentioned theory and later idea.
I wonder how information exists does anyone know.
It seems a strange idea.
Does anyone know more about this new idea?

[AlexN]

The idea in my opinion seems sound enough. The mass and the energy that passes the event horizon has to go somewhere. We are fairly certain at least some of this is ejected as heat (hawking radiation) energy in (for argument sake, an astronaut) energy out (heat radiation) but as the article states. The energy released would not be coherent to any measure.

[bojan]

Originally Posted by gary

.... According to Hawking's idea, the particles that enter a black hole leave traces of their information on the event horizon....

This feels actually quite intuitive..
Any object falling towards BH will reach c at the event horizon.. so time for that object (from the point of view of the external observer) will stop, and object (or what's left of it afer spagetization) will appear as being "pasted" on the "surface" defined by event horizon.. the information will stay there for ever as far as the outsde world is concerned..

[xelasnave]

Hi Bojan
As you know I can't do the math however from my modest understanding of the matter I doubt if anything would being travelling at C.
The event horizon is I think a boundary where escape velocity would have to be greater than C, at least this means nothing can leave not even light.
However I doubt if that allows us to conclude incoming matter will reach C at that boundary, the event horizon.
It is my understanding that to reach C matter even of a miniscule mass would require infinite energy.
Do you know if the equations support your view that an object would reach C at the event horizon.
If less than C will an object experience time dilation such that it will appear to remain stationary to an observer.

[AlexN]

Not only will it require infinite energy but it will gain infinite mass (thusly requiring infinite energy to accelerate any faster) will it not? If so then where does this mass go. If a 5m solar mass black hole devours a 2m solar mass black hole will the resulting black hole be 7 million solar masses (or close to that amount less the mass of the particles belched out as hawking radiation)

I am of course simply babbling right now as my understanding of black hole physics is infantile at best. (currently reading and working through "gravity from the ground up")

[bojan]

Object will not "experience" or feel time dilation itself.. but we observers will see the time for object slows and eventually stops, when the object reaches event horizon.
As for speed of fall into BH.. imagine the opposite: If object starts to move from event horizon away from BH with c (ok - ALMOST c..) the gravity of BH will slow it down, until it stops infinitely far away (We also have to imagine that in this universe there are no other objects).
The escape velocity for BH at the event horizon is c

[Mark_Heli (Mark)]

Is this really a new theory? It sounds like the holographic principle proposed by Gerard t'Hooft and Leonard Susskind.

Maybe I am missing something, but what is new in what Stephen is proposing?

[xelasnave]

I imagine say an object approaching a black hole this way.
Presumably it would and drawn into an orbit spiralling in in ever decreasing orbits.

Would an object perform like that. Wouldn't the high speed throw it out of orbit well before it got in an orbit close to the event horizon.
Sorry I am missing something and I blame my brain

[xelasnave]

Wouldn't there be an orbit outside the event horizon where matter would have to convert to energy which would be the way I think it may work.
All matter would have to change to energy to cross the event horizon.

[xelasnave]

And that energy must follow decreasing orbits once past the event horizon so spaghettifacation would be horizontal.
Matter can only approach a black hole by decreasing orbits.
Wouldn't frame drag5ging predict this?

[AlexN]

An orbit would be involved and as you say an ever decaying orbit until the gravitational force tore the matter into pieces. How would it convert to energy. Say in the case of a planet. I would imagine it would tear apart, then the resulting parts would spread out and out untill the planet was no more than countless atoms spinning faster and faster riding the accretion disc into the event horizon.. Any thoughts on what from there.

And yes in all the simulations I have run creating extreme gravity in a small area and sending particles at it almost always resulted in the particles being flung out into the universe or falling directly in. Depending on the vector at which the particle comes into contact with the gravitational field of the black hole some were caught into a highly eccentric elliptical orbit.


I might make it my personal mission to calculate the orbital velocity and period at a close range to a black hole.

[xelasnave]

The implication would be a sprial of energy going a C
It is hard to imagine any photons escaping

[xelasnave]

And entry could only be from an orbit on the equator.
A direct drop would seem on probability impossible.
No but rare and unusual.
A direct hit of matter probably could not happen.
I know I am probably wrong.
But in bring wrong I will learn more.

[xelasnave]

Alex may I ask what or rather how do you run your simulations.
Do you have program if so could you tell me how it works. Does it use GR?

[AlexN]

Its a software called Triana, its available through Cambridge University Press and was included with the purchase the book I am currently working through "Gravity from the Ground up" by Bernard Schultz

[xelasnave]

Looks interesting from the book site.
I can only use my imagination but it suggests above.
Whatever heads to a black hole must assume an orbit as I imagine it.
But I think any simulation on a computer may well show such orbits are inevitable.
I don't know but I can't stop thinking about it.

[bojan]

I managed to download Triana:
http://triana.cs.cf.ac.uk/triana-release/

This looks like a powerful system simulation app, similar to mathlab, but with many various tools (algorithms) included.

AlexN, are you willing to share with us a BH model you used in your simulations?

[xelasnave]

I have found that only 44 per cent of mass is converted to energy when matter encounters the black hole.
I have lost the link where I read that.