Black Holes - Roger Blandford (SETI Talks)

SETI Talks Archive: http://seti.org/talks

Black holes are popularly associated with death and destruction (excluding romances dealing with the redemptive properties of wormholes). However, their conventional astrophysical role is now seen as regenerative and they play a major role in the formation and evolution of galaxies stars and, arguably, organic molecules. Some possible ways in which they may impact the research of the SETI Institute will be discussed and ways in which they may have played a role in the history of our solar system will be briefly discussed.

Category:

Science & Technology

Tags:

• seti institute
• seti
• black holes
• roger blanford
• stanford
• kavli institute

[Typho0n86]

@1.06.35, that a black hole will evaporate if you wait a long time 10^56~ why cant they say that the big bang came from a black hole!!!!! its all there!!!!!!!!!!

[setiinstitute]

@Typho0n86 Hi Typhoon, yes Lee Smolin has this idea as part of his Fecund Universe theory. You may want to google Lee Smolin to check it out, it's an interesting idea about evolutionary universes - not much proof to it, but interesting.

[bdogshredder]

@cipher2 It aaaa, umm , KILLS me! I can't watch it.

[cipher2]

Can you count how many times he says uhh, ahh and uum? If you can than you also possess the ability to count the stars in the universe or the grains of sand on the beaches of earth....uh um ahhh, uh uh, um. Never understood why intellectuals need so many filler words.

[Typho0n86]

@ 26.44 never to return.. what about a big bang??

[retepvosnul]

@dgumbrecht You are right, the upper limit for neutron stars is the Tolman-Oppenheimer-Volkoff limit. Different sources give different numbers, but it ranges from 1.5 to 3 solar masses. So indeed Oppenheimer, in a way gave us reason to believe this is not possible. My bad.

[dgumbrecht]

@retepvosnul

From my understanding of the Chandrasekhar limit, it applies only to the upper mass limit for a white dwarf star. As neutron stars consist of an entirely different form of matter than white dwarves, perhaps Oppenheimer did the physics for neutron star collapse.

This is speculation on my part, as I don't know the relevant science from Oppenheimer.

[retepvosnul]

"two neurton stars of 1.4 solar masses combined trying to become a 2.8 solar mass neutron star.. Can not do that, Oppenheimer told us that".

Is that right ? I thought Shandrasakar told us that, hence the Shandrasakar limit of 1.4

[tomy4you]

@impis8

what do you mean by speculation?

For instance Prof. Reinhard Genzel, Director of the Max Plank Institute was observing the centre of Milky Way for nearly (or over) 10 years and discovered super-massive black hole there, for which he was awarded the Shaw prize (2008). Start reading on this. It used to be speculation (early XX) but it's been now becoming common knowledge...

[johnjaksic61]

@sbergman27

Correctly put and very enjoyable lecture.