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Sat, Oct. 1st, 2005, 12:43 am
disassembly_rsn: Professor Hawking in the USA this November, evidently

Since I haven't seen a mention of it here...

If Google is to be believed, Dr. Hawking will be at the San Jose Center for Performing Arts in San Jose, CA on 7 November, and at the Paramount Theatre in Oakland CA on 10 November.

He'll be in Seattle on November 16th at the Paramount Theatre.

Sun, Sep. 18th, 2005, 05:42 am
quiveringbass: (no subject)

Really, what came first? The chicken or the egg?

Fri, Jul. 8th, 2005, 10:52 pm
sistershima: (no subject)

since this community has not been updated since February...I'll post some newly discovered truths about Mr. Hawking's findings taken from http://www.newscientist.com/article.ns?id=dn6151


Hawking cracks black hole paradox
19:00 14 July 2004
Exclusive from New Scientist Print Edition
Jenny Hogan



After nearly 30 years of arguing that a black hole destroys everything that falls into it, Stephen Hawking is saying he was wrong. It seems that black holes may after all allow information within them to escape. Hawking will present his latest finding at a conference in Ireland next week.

The about-turn might cost Hawking, a physicist at the University of Cambridge, an encyclopaedia because of a bet he made in 1997. More importantly, it might solve one of the long-standing puzzles in modern physics, known as the black hole information paradox.

It was Hawking's own work that created the paradox. In 1976, he calculated that once a black hole forms, it starts losing mass by radiating energy. This "Hawking radiation" contains no information about the matter inside the black hole and once the black hole evaporates, all information is lost.

But this conflicts with the laws of quantum physics, which say that such information can never be completely wiped out. Hawking's argument was that the intense gravitational fields of black holes somehow unravel the laws of quantum physics.

Other physicists have tried to chip away at this paradox. Earlier in 2004, Samir Mathur of Ohio State University in Columbus and his colleagues showed that if a black hole is modelled according to string theory - in which the universe is made of tiny, vibrating strings rather than point-like particles - then the black hole becomes a giant tangle of strings. And the Hawking radiation emitted by this "fuzzball" does contain information about the insides of a black hole (New Scientist print edition, 13 March).

Big reputation
Now, it seems that Hawking too has an answer to the conundrum and the physics community is abuzz with the news. Hawking requested at the last minute that he be allowed to present his findings at the 17th International Conference on General Relativity and Gravitation in Dublin, Ireland.

"He sent a note saying 'I have solved the black hole information paradox and I want to talk about it'," says Curt Cutler, a physicist at the Albert Einstein Institute in Golm, Germany, who is chairing the conference's scientific committee. "I haven't seen a preprint [of the paper]. To be quite honest, I went on Hawking's reputation."

Though Hawking has not yet revealed the detailed maths behind his finding, sketchy details have emerged from a seminar Hawking gave at Cambridge. According to Cambridge colleague Gary Gibbons, an expert on the physics of black holes who was at the seminar, Hawking's black holes, unlike classic black holes, do not have a well-defined event horizon that hides everything within them from the outside world.

In essence, his new black holes now never quite become the kind that gobble up everything. Instead, they keep emitting radiation for a long time, and eventually open up to reveal the information within. "It's possible that what he presented in the seminar is a solution," says Gibbons. "But I think you have to say the jury is still out."

Forever hidden
At the conference, Hawking will have an hour on 21 July to make his case. If he succeeds, then, ironically, he will lose a bet that he and theoretical physicist Kip Thorne of the California Institute of Technology (Caltech) in Pasadena made with John Preskill, also of Caltech.

They argued that "information swallowed by a black hole is forever hidden, and can never be revealed".

"Since Stephen has changed his view and now believes that black holes do not destroy information, I expect him [and Kip] to concede the bet," Preskill told New Scientist. The duo are expected to present Preskill with an encyclopaedia of his choice "from which information can be recovered at will".


this is big news, indeed

Wed, Feb. 23rd, 2005, 11:03 pm
bomb_ars_punani: Newbie, just read A Brief History of Time

I just finished reading A Brief History of Time, and I was blown away. Hawking makes everything sound so simple, the first two chapters covered everything I learned in a year of AP Physics. It's a talent that seems common to the great theoretical physicists-- they deal in such an esoteric field, but they're able to explain it so lucidly. Has anyone here read Michio Kaku? He reminds me of Hawking in that they both explain things with such ease.

Mon, Dec. 6th, 2004, 01:20 pm
aporia_flame: another in. HELp

Hi, this is another kid into the community.
I've got a question in urgent need for a reply.

In e=mc^2 einstein stated that energy can be turned into matter, and matter can be turned into energy. However, if matter colliding with antimatter creates energy, then does that mean that "energy can be turned into matter PLUS antimatter" ?

Thanks

Thu, Nov. 25th, 2004, 09:40 pm
nkc: (no subject)

I'm a bit confused on the string theory. I am not completely familiar with it, and when invited to listen to a conversation/debate over it, I had one colleague talking about how it was ridiculous because as he said, "nothing in the world could ever possibly be random". This was highly refuted by the other colleague for several reasons. Any of your thoughts, (or perhaps a definition for me)? Kindly appreciated.

Sun, Jul. 18th, 2004, 08:55 pm
apa_grapa: long ramble

Hey. This is my first post, and I thought I should enter something because I think this community could be expanded, Stephen is the man!

My bro (21) came home about 2 hours ago and we started talking about the universe (as we often do) and he explained the numerous facts of physics and the known universe that he has lodged in that genius-brain of him, and I learned and discussed my views. Anyway, the main topic was of time and light speed, and a little of the string theory.

Some interesting things I learned: Time is just another dimension and it is possible to travel 100 mph in space, but not time because you are on different axes. Therefore, you could spend 4 days travelling on the space axis, but once you turn back to the time axis, nothing has happened (there are other desriptions of this in greater detail, but interesting nonetheless)
The "perfect clock" would be two perfect mirrors lying horizontal, parallel to each other, about 6 inches from one another, with a photon bouncing up and down. It would go on forever at the same speed. Photonds don't decay. Unfortunatley, this is impossible because we have neither the ability to make two perfectly perfect mirrors, nor the technology to keep track of the photon because it would be travelling at the speed of light. Also, there's no way to get the photon to bounce perfectly vertical either, even one degree off and it would bounce away.
If you travelled at the speed of light around the world and you were able to live, be coherent, you could view the world and they could view you, etc., what would take you an hour to do as you saw yourself, would take a year to watch to those on earth. And what would take a year on earth would take you an hour to watch. Therefore, you would view the world in an hour at super fast speeds, and the world would view you in a year at super slow speeds.
Confused yet?
If the earth were to suddenly stop spinning and rotating, no matter what, we would all die. Because our bodies are also travelling as fast as the earth is moving (don't know the exact number), to suddenly stop would either throw us until we hit something at super fast speeds and die, or because of the g-forces, our bodies would turn to jelly/dust/whatever is gruesome. In any case, we would die.

Sorry if any of this is wrong, it is 5 in the morning and I haven't gone to bed yet. Also, please excuse me if any of this is basic knowledge. I love physics, but haven't taken any classes. I read books, my bro explains it to me, then goes and tells me more than I could ever comprehend in a day.

-Becky

ps: 15 (16 in 2 weeks), CA, junior in the upcoming year, taking physics class in 2005.

Wed, Jun. 16th, 2004, 12:48 pm
iampurgatory: (no subject)

I am a lower division physics student. actually I just failed electricity and magnetism so I am not that well up to speed. i blame the professor, but I still love physics! one thing I have been wondering about is the string theory.

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