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Daniel Ellsberg On WikiLeaks, Google and Facebook 87

angry tapir writes "The Silicon Valley companies that store our personal data have a growing responsibility to protect it from government snooping, according to Daniel Ellsberg, the man who leaked the Pentagon Papers. Discussing the growing role of Internet companies in the public sphere, Ellsberg said companies such as Google, Facebook and Twitter need to take a stand and push back on excessive requests for personal data." Ellsberg spoke as part of a panel at an event from the Churchill Club, which included Clay Shirky, Jonathan Zittrain and others discussing the WikiLeaks situation.

Comment Re:A wise man once said.... (Score 1) 389

“What makes us human”is by definition everything that we are, which includes both our impulses and our ability to control our impulses, and everything else besides.

“What makes us human as opposed to animal” is the question you seem to be answering, and it is invalid, because "human" is an element of "animal".

Iphone

Apple Releases IOS 4.3 Beta To Developers 101

m2pc writes "Apple has just released iOS 4.3 beta to developers. New features include: Developer access to AirPlay API, Four and Five-finger gestures, and the return of the hardware orientation lock for iPad, a feature that upset many when Apple suddenly removed this feature with no software option to re-enable it. Also interesting to note is the lack of mention of the Mobile Hotspot feature rumored to be included in 4.3 for all iOS devices by the Verizon announcement yesterday."

Comment Re:Interesting (Score 1) 140

Heh - true.

It's interesting to note how small they have to be, though: according to wikipedia, to radiate more than the it absorbs from the cosmic miscrowave background, the BH would have to be lighter than the moon. In other words, since the microwave background is always decreasing, all stellar-remnant BHs in the universe have always been, and are still (and for the next N times the age of the universe, will remain) increasing in size.

Comment Re:Interesting (Score 1) 140

I misunderstood the parent to my post –sorry. My response was elaborating on the first AC who pointed out gman003's misconception – trying to add some figures.

I think a lot of people have heard that "block holes gradually evaporate", without having read any further, making the erroneous assumption about the timeframes involved is understandable.

In fact:

  1. large black holes evaporate so slowly they are likely to be the most long-lived objects in the universe
  2. at the current background radiation level of the universe, even small black holes absorb much more radiation than they emit, and are therefore growing at the present time
  3. quasars are enormous black holes –many millions of solar masses –and are therefore calculated to be emitting radiation ("evaporating") so slowly as to result in a mathematical absurdity.

Comment Re:Interesting (Score 1) 140

Oh my apologies. To be fair, your post was ambiguous. I thought you were saying the black hole isn't consuming matter, therefore it was evaporating faster. In fact you were suggesting it is merely inactive, which is another reason the OP’s conclusion is erroneous. I hope the OP found what I wrote informative, anyway.

Comment Re:Interesting (Score 5, Interesting) 140

Nope, even then. You need to read up a little about the timeframes here.

The evaporation of black holes according to Hawking radiation is an unimaginably, incomprehensibly, comically slow process. So slow, that in this universe, the passive absorption of the cosmic microwave background is sufficient to render it irrelevant –the black hole still absorbs background photons at a greater rate than it generates radiation:

A stellar black hole of one solar mass has a Hawking temperature of about 100 nanokelvins. This is far less than the 2.7 K temperature of the cosmic microwave background. Stellar mass (and larger) black holes receive more mass from the cosmic microwave background than they emit through Hawking radiation and will thus grow instead of shrink. To have a Hawking temperature larger than 2.7 K (and be able to evaporate), a black hole needs to be lighter than the Moon (and therefore a diameter of less than a tenth of a millimeter). (wikipedia.org)

Elsewhere I have seen the figure of 10^61 times the age of the universe for the evaporation (and this is in a black-body condition: no matter absorbed whatsoever) of a BH of merely 30 solar masses. Recall we are talking about a Quasar: something hundreds of millions of solar masses and up. These things have lifetimes so vast as to render even the word "astronomical" meaninglessly trifling. Think numbers of years with more digits than you could write in your lifetime.

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