econintersect.com
       
  

FREE NEWSLETTER: Econintersect sends a nightly newsletter highlighting news events of the day, and providing a summary of new articles posted on the website. Econintersect will not sell or pass your email address to others per our privacy policy. You can cancel this subscription at any time by selecting the unsubscribing link in the footer of each email.



posted on 30 August 2015

Is Hawking Any Closer To Solving The Puzzle Of Black Holes?

from The Conversation, The Conversation

-- this post authored by Geraint Lewis, University of Sydney

Stephen Hawking said something! And again the international media is all a'buzz.

The physics community is a little more muted, but after hearing the pronouncements of the famous theoretical physicist, of supertranslations and horizons, like those listening to Douglas Adams's Deep Thought, you might be wonder what the actual questions is.

We don't have to go far as a little over a year ago I wrote about Hawking's previous proposed solution to the same problem, namely the paradox of information and black holes.

All about the information

As a quick reminder, the core issue is the apparent forgetfulness of black holes. Black holes can swallow anything that comes too close, squashing all matter into the apparently point-like singularity on the way.

Only a few properties of the infalling material are remembered, imprinted on the black hole's gravitational field, namely the mass, the charge and the angular momentum. All other properties appear to be promptly forgotten; neglecting spin and charge, all black holes of the same mass are identical, whether they were built of collapsing stars or from an immense number of tennis balls.

This "no hair" of black holes, telling us that they can only remember the mass, spin and charge of infalling objects, has been known for half a century.

But as I noted previously, the other pillar of modern science, quantum mechanics cares deeply about information, and to lose information is not simply careless, it downright forbidden. And somehow black holes should remember the quantum details of all the material that ever fell in.

This is especially important given Hawking's key insight into black holes, namely that they can evaporate, leaking a feeble radiation due to quantum mechanical interactions in their vicinity. This featureless radiation robs the black holes of mass, diminishing its gravitational field until it vanishes in a a final puff.

But after it has completely evaporate, where did all that quantum information go? The potential solutions and counter solutions to this have given us the black hole wars, were key researchers have argued about different ways that information could escape.

Latest salvo

Hawking's latest pronouncement is the next salvo in the war, changing his view that the information is somehow stored and is eventually released when the black hole in the final stage of evaporation.

The new solution involves supertranslations, something that I have yet to get my head properly around. But it seems to rely on the well known fact that an "image" of infalling matter seems to get imprinted onto the "surface" of a black hole.

Eternal ghosts

A quick explanation. Imagine you drop a green iguana into a black hole (no iguanas were hurt during the writing of this article). Initially, as you watch, you see the iguana happily wriggling about as it falls. But as it gets closer, the light reaching your eyes has had to struggle out of the ever increasing gravitational field, and this struggle has robbed the light of some energy, and the iguana starts to change colour, from green to red.

Due to the effects of relativity, the strong gravitational field also influences clock rates, and the iguana's wriggling slows.

As it continues to fall, the effects of relativity grow, and eventually it crosses a point of no return, the Event Horizon, and any light from the iguana is also destined to head to wards the black hole centre.

But just before it crossed the Event Horizon, there was the last light from the iguana's skin. This light is heading outwards at the speed of light, but is held in place by the immense gravity. This last light remains as a final image of the infalling iguana, an iguana that no longer exists.

There's the information, sort of

Back to Hawking! It seems that such images can be treated as records of all of the things that fell in, a record of their quantum information (I am waving my hands a little as I type this). And this information gets encoded into the radiation leaking from the black hole, steadily carrying it away as it evaporates.

The process, however, seems to scramble the radiation, making it effectively useless (meaning an awful lot of detective work is required to piece together the details of what actually fell in). The information is seemingly saved and lost at the same time! Paradox solved.

Is this the last shot in the Black Hole wars? I seriously doubt it. This is an idea, one of many, that has been proposed, and a paper detailing the actual process has yet to appear.

When it does, it will be digested by the community of researchers working in this seemingly esoteric corner of physics, and arguments and counterarguments are likely to fly. There will be talks at conferences, discussions over coffee, and arguments in corridors, the usual way that science proceeds.

But the general public is unlikely to hear anything until we have our next "Hawking says something" story.

The ConversationGeraint Lewis is Professor of Astrophysics at University of Sydney

This article was originally published on The Conversation. Read the original article.

>>>>> Scroll down to view and make comments <<<<<<

Click here for Historical News Post Listing










Make a Comment

Econintersect wants your comments, data and opinion on the articles posted.  As the internet is a "war zone" of trolls, hackers and spammers - Econintersect must balance its defences against ease of commenting.  We have joined with Livefyre to manage our comment streams.

To comment, using Livefyre just click the "Sign In" button at the top-left corner of the comment box below. You can create a commenting account using your favorite social network such as Twitter, Facebook, Google+, LinkedIn or Open ID - or open a Livefyre account using your email address.



You can also comment using Facebook directly using he comment block below.





Econintersect Contributors


search_box

Print this page or create a PDF file of this page
Print Friendly and PDF


The growing use of ad blocking software is creating a shortfall in covering our fixed expenses. Please consider a donation to Econintersect to allow continuing output of quality and balanced financial and economic news and analysis.


Take a look at what is going on inside of Econintersect.com
Main Home
Analysis Blog
Joan Robinson’s Critique of Marginal Utility Theory
The Truth About Trade Agreements - and Why We Need Them
News Blog
Goals Come With A Hefty Price Tag At The Emirates
Facebook Strongest On Home Ground
Defence Budgets Are Surging In The Baltic States
It's Been A Turbulent Start, But Juno Is Now Delivering Spectacular Insights Into Jupiter
The World's Most Reputable Cities
What We Read Today 07 December 2016
October 2016 Consumer Credit Headlines Say Year-Over-Year Growth Rate Declined
Disabled Veteran And His Service Dog Get Job At Hardware Store
October 2016 JOLTS Job Openings Rate Shows Insignificant Year-over-Year Growth
Do Rises In Oil Prices Mean Rises In Food Prices?
Are Mobile Phone Payments Secure?
Infographic Of The Day: 12 Reasons To Let Your Employees Play Games
Early Headlines: Asia Stocks Up, Oil Down, House Has Stopgap $ Bill, Trump Sold All Stock, Euro Holding On, May Doubles Down, India Economy Struggles, Oz GDP Contraction And More
Investing Blog
Trumpsternomics And Economic Growth
The Real 401k Plan Manager 07 May 2016
Opinion Blog
Italy Confronts The European Elite
The US Government Needs To Spend More
Precious Metals Blog
Silver Prices Rebounded Today: Where They Are Headed
Live Markets
07Dec2016 Market Close: Wall Street Records New Highs, Health-Care Stocks Tumble, Crude Prices Stall At $50 Handle, New Fears Of A Correction Are Looming
Amazon Books & More






.... and keep up with economic news using our dynamic economic newspapers with the largest international coverage on the internet
Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government



Crowdfunding ....






























 navigate econintersect.com

Blogs

Analysis Blog
News Blog
Investing Blog
Opinion Blog
Precious Metals Blog
Markets Blog
Video of the Day
Weather

Newspapers

Asia / Pacific
Europe
Middle East / Africa
Americas
USA Government
     

RSS Feeds / Social Media

Combined Econintersect Feed
Google+
Facebook
Twitter
Digg

Free Newsletter

Marketplace - Books & More

Economic Forecast

Content Contribution

Contact

About

  Top Economics Site

Investing.com Contributor TalkMarkets Contributor Finance Blogs Free PageRank Checker Active Search Results Google+

This Web Page by Steven Hansen ---- Copyright 2010 - 2016 Econintersect LLC - all rights reserved