Black holes 'important'

2010-09-02 09:24
The University of Chicago's Bob Wald has spoken on black holes in Cape Town. (Duncan Alfreds, News24)

The University of Chicago's Bob Wald has spoken on black holes in Cape Town. (Duncan Alfreds, News24)

Multimedia   ·   User Galleries   ·   News in Pictures Send us your pictures  ·  Send us your stories

  • Astronomy
    Learn about famous astronomers, the solar system, stars, and other aspects of astronomy Was R174.95 Now R148.71
    buy now

Cape Town - A University of Chicago professor studying black holes says they are an important phenomenon and may lead to new understanding of the nature of the "real universe".

"They (black holes) are interesting objects from a fundamental physics point of view and play an important role in astrophysics processes. They help us to understand what's going on in the real universe," Bob Wald told News24 after his lecture at UCT.

A black hole is a region of spacetime where gravity is so strong that nothing - not even light - can escape. They arise in nature as the end products of the complete gravitational collapse of sufficiently massive bodies like stars.

"There are black holes at the centre of most galaxies, and the one at the centre of our galaxy is about four million solar masses," said Wald, who is in SA for the first time, and just recently hiked up Table Mountain.

However, despite being a "perfect absorber of everything", black holes do not swallow up the galaxy because of the speed of bodies around it, much like the Earth doesn't not fall into the sun, despite the latter's gravity.


"Black holes have a finite temperature, despite their gravity. One would think that their temperature should be absolute zero (-273.15°C) but they are subject to quantum effects.

"Given that black holes have a finite temperature, they should evaporate in a finite amount of time," said Wald.

He said that much of the theory around the study of black holes was developed by physicist Stephen Hawking and hopes that observations of black holes will confirm the theory of general relativity.

"I'm still excited by black holes, there's still much to be learned and it might teach one about what's going on. We need to fill in the details of astro-physical processes."

Most remarkable of the theoretical developments is the relationship between certain laws applying to black holes and the ordinary laws of thermodynamics, particularly the fact that - due to quantum processes - black holes "emit" thermal radiation.

Wald said study of physics and cosmology was a popular field of study in the US and attracted good students, illustrating the difference between the industrialised economy and SA as a developing country where there was a chronic shortage of skills.

"The gravitational waves results in about five years excites me - it would be good to confirm the theory. What is needed is a theory that includes general relativity and quantum theory, but there are special difficulties when one tries to formulate a quantum theory of gravity."

- Follow Duncan on Twitter

Read more on:    astronomy

Read News24’s Comments Policy publishes all comments posted on articles provided that they adhere to our Comments Policy. Should you wish to report a comment for editorial review, please do so by clicking the 'Report Comment' button to the right of each comment.

Comment on this story
Add your comment
Comment 0 characters remaining

Inside News24


SAPS waited too long to complain about ad - DA

The DA has told a public hearing that the SA Police Service was "hopelessly out of time" to lodge a complaint against its election advert.


Latest elections multimedia

13 days to elections - news you need to know
11 Julius Malema quotes you'll never forget
DA won't get 30% - Zille
The EFF's ad was banned, see why
  • Thursday Kenilworth - 12:59 PM
    Road name: M5 Northbound
    DELAYS between Ottery Road and Race Course Road
  • Thursday Brackenfell - 12:39 PM
    Road name: Frans Conradie Drive Eastbound
    SLOW TRAFFIC approaching Okovango Road
More traffic reports...

Jobs in Cape Town [change area]

Property [change area]

Travel - Look, Book, Go!

Escape winter, head to Mauritius

Escape winter by spending 7 nights in Mauritius' tropical bliss from R13 215 per person sharing. Includes return flights, airport transfers and accommodation. Book now! - shop online today

24 hour sale- 30% off beauty products

Today only, get 30% on all hair care, skincare, selected cosmetics and fragrances. Offer expires midnight 24 April. While stocks last. Shop now!

Mother’s Day special offers!

Spoil mom with these awesome specials that will warm her heart. Shop now!

Twisp – the smoking alternative

Buy any 2 refills for R250 and save R149. Offer valid while stocks last. Shop now!

25% off bestselling books!

The Real Meal Revolution by Tim Noakes, Jeffrey Archer’s Be Careful What You Wish for, Man’s Search for Meaning by Victor E. Frank and many more titles. Shop now!

Mother’s Day specials on appliances

Browse our range of Mother’s Day appliances to spoil and pamper mom. Offer valid while stocks last. Shop now!

OLX Free Classifieds [change area]

Samsung Galaxy s4

Mobile, Cell Phones in South Africa, Western Cape, Cape Town. Date October 24

Best bargain in big bay

Real Estate, Houses - Apartments for Sale in South Africa, Western Cape, Cape Town. Date October 25

VW Golf 6, 1.6 Trendline (Excellent condition)

Vehicles, Cars in South Africa, Western Cape, Cape Town. Date October 25

Apple iPad 2 White 16GB 9.7" Tablet With WiFi & 3G

Two cameras for FaceTime and HD video recording. The dual-core...

From R5727.00

I'm shopping for:


You may be more sensitive today and can be influenced easily by the energies around you. Try not to be swayed too much by more

There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.