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Submission + - P != NP may finally be proven (newscientist.com)

u19925 writes: If the paper submitted by Vinay Deolalikar turns out to be right, then finally one of the most important theorem of computer science and mathematics is proved. This is one of the Clay Mathematics Institute's seven Millennium Prize problems so the author may be rewarded well for his effort.

Comment Extraordinary claims require extraordinary proof (Score 1) 405

The claim is extra-ordinary but unfortunately the proof is not. It is well known for a long time that the equations of quantum mechanics violates equivalence principle. Precisely for this reason, we don't have satisfactory theory of quantum gravity. So there is nothing new in terms of it. If I interpreted the contents of the paper right, the authors are suggesting a way to create an experiment which can show that m_i and m_g are indeed different, but these experiments have not been performed yet.

Comment Inside black hole is not necessarily exotic (Score 1) 364

Most of the calculations about black hole are based on steady state. However, the time it takes to reach this state is of order of event horizon size divided by speed of light. Larger the black hole, larger the time. Thus if you have a black hole of the size of our visible physical universe, it can take billions of years to reach steady state. During this billions of years, life can go on normally! In fact the equation of universe with omega greater than one (which means that the whole universe would eventually contract and collapse to singularity) are almost same as a black hole with event horizon of the size of the universe.

However, most black holes are much smaller in size and hence are much more exotic. From what I understand, it is impossible to see any events which happened inside the event horizon. Thus you may be able to supply enough charge and angular momentum to remove its event horizon and reveal the interior of the black hole, but that would only let you observe the events that happened after you pass the charge and angular momentum (there is nothing new here, it is known for a long time). Any event that happened inside event horizon is forever lost (from classical point of view). From QM perspective, those events carry signature in Hawking radiation but that has nothing to with changing event horizon by supplying charge and angular momentum.

Comment Re:My Estimate ... (Score 4, Informative) 799

Ok, slightly less mathematical and scientific than you. The article says 10,000+ sq miles surface area slick. Assuming this is 1 molecule thick and assume that each molecule is touching each other and atom size of 1 angstrom and average atomic weight of 9 au, we get total volume of 12 million Ga. Again the article claims this is about 20% of total, so we get total of 60 million Ga. this is about 25 times that of the estimate based on 5000 barrels a day.

Comment Waiting for Recall (Score 0, Troll) 217

Direct AC connection? 110-240V? I don't know about you guys, but I ain't gonna put that damn thing on my lap. This is a laptop. I have spilled coffee, juice, other drinks on my laptops. I don't want 240V shock on my private parts. I let my young kids to use laptop too and certainly wouldn't allow this one to them.

Comment Summary of judgement (Score 1) 330

IANAL, but I actually read the whole document. The appeals court concluded that the summary judgment granting Unix copyright to Novell was wrong and a trial is required. However, if you read the whole judgment, you will get a feeling that the judge is trying to say that SCO has better claims on Unix copyright than Novell (however, the court didn't have authority to make that decision). So if SCO proceeds with the trial there is a good chance that it might win. Will it get funding to pursue the trial? The judge didn't say anything about it and I hope it doesn't.

Comment The loss is all microsoft's (Score 1) 756

The loss is all microsoft's. My company uses Cisco VPN dialer which works on 32 bit Vista but not 64 bit. Year and a half ago, unknowingly, I purchased a new PC with 4 GB RAM and had to return it. I am back to my old PC which already has 2 GB RAM. I am in no mood to buy a new machine if it comes with memory limit which is only 50% more than my 7 year old PC. I will purchase a new PC when my company supports 64 bit Windows (At this point, I am not prepared to totally ditch windows. Too much legacy stuff). If it supported more RAM, I would have purchased a PC 18 months ago and would have been ready to upgrade to Windows-7.

Comment I am a skeptic (Score 1) 355

I strongly doubt you can make UDD in any large amount. The laws of QM dictates that electrons cannot reach closer to nuclei than Bohr's radius and hence they cannot cancel out the p-p electrostatic repulsion. In tiny amount, this may occur if somehow you can manage to create some external forces which adds in a right way, but at large scale, you can't do that. This is as bizarre as cold fusion and I refuse to believe it (I will believe it if they can make 0.01 cubic milli-meter of UDD with a mass of 1 gm and is stable for more than 1 sec).
Security

Submission + - All your passwordsRus

u19925 writes: If this story at c|net is true, then all your passwords are gone. The authors claim that they can recover your keystrokes from 65 feet away by listening to electromagnetic waves. How would you protect against such attacks? Even if you can prevent this in your home by setting a shielded environment, how would you prevent your next door office mate from listening to your keyboards? That means that if you are a senior executive member in your company, a junior staff in a cubicle knows your bank passwords! A hacker can even take a laptop in bank and monitor every keystroke of bank staff. The only consolation here is that if lots of people are typing together, it may be hard to decode. Very soon, we will see a class of "secure keyboards" surfacing in the market.
Announcements

Submission + - Missing element in electric circuits (informationweek.com)

u19925 writes: Engineers at HP have discovered a new element of electric circuit which was predicted in 1971. Most people are familiar with resistors, inductors and capacitors which are three basic passive circuit elements. Using complex mathematics, Leon Chua in 1971 predicted the existence of fourth element which he named memritsor. Until recently, not many people knew how to make one. Senior Fellow R. Stanley Williams at HP has not only shown how to make one but also explains how it can be used in nano-circuitry in this article (Information Week

Comment UMPC? (Score 1) 322

Would Apple get into the business of UMPC/WindowsMobile space by buying PA Semi? They already have a MacOS for Power platform and PA Semi can be used in a small form factor. Other obvious applications could be Apple TV, set top boxes etc. Whatever it is, Apple would want to dive into it with full force to justify a purchase.

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