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Sun, Apr. 20th, 2014, 03:00 pm
snopes_dot_com: Tiger Beat

Have Japanese scientists successfully cloned a saber-tooth tiger?

Fri, Apr. 18th, 2014, 03:00 pm
snopes_dot_com: 100% Beef

Does McDonald's buy their meat from a company called '100% Beef,' which allows them to legally but deceptively claim they use 100% beef in their hamburgers?

Fri, Apr. 18th, 2014, 03:25 pm
computcomplexit: Announcements

Time for a short rundown of announcements.

  • STOC will be held May 31-June 3 in New York City. Early registration and hotel deadline is April 30. Student travel support requests due by this Monday.
  • The newly renamed ACM Conference on Economics and Computation (EC '14) will be held in Palo Alto June 8-12. Early registration deadline is May 15. Hotel deadline is May 19th but the organizers suggest booking early because Stanford graduation is June 13.
  • The Conference on Computational Complexity will be held June 11-13 in Vancouver. Local arrangements information will be posted when available.
  • The ACM Transactions on Algorithms is searching for a new Editor-in-Chief. Nominations due May 16.
  • Several of the ACM Awards have been announced. Robert Blumofe and Charles Leiserson will receive the Paris Kanellakis Theory and Practice Award for their "contributions to robust parallel and distributed computing."
  • Belated congratulations to new Sloan Fellows Nina Balcan, Nayantara Bhatnagar, Sharon Goldberg, Sasha Sherstov, David Steurer and Paul Valiant.

Fri, Apr. 18th, 2014, 09:45 am
daily_wtf: Error'd: Social Insecurity Number

"Adding an account on, it asks for the last 4 digits of my SSN and for the first 3 digits," John A. wrote, "Seriously? There are only 100 combinations left to guess the full SSN!"...

Fri, Apr. 18th, 2014, 03:00 pm
snopes_dot_com: Amazing Catch

Video shows a ball girl making an amazing catch at a minor league baseball game.

Fri, Apr. 18th, 2014, 03:00 pm
snopes_dot_com: Fargo

Was the kidnapping and murder plot of the film 'Fargo' based on a true story?

Thu, Apr. 17th, 2014, 03:00 pm
snopes_dot_com: Jews Ordered to Register in Ukraine

Have Jews in eastern Ukraine been ordered to register with the government or else face loss of citizenship and deportation?

Thu, Apr. 17th, 2014, 03:00 pm
snopes_dot_com: Easter Lore and Superstitions

A compendium of superstitions and lore associated with Easter.

Thu, Apr. 17th, 2014, 03:00 pm
snopes_dot_com: Fare Warning

Has congress has introduced a bill requiring military veterans to inform their neighbors about their combat service?

Thu, Apr. 17th, 2014, 03:00 pm
snopes_dot_com: Self Service

Has the American Psychiatric Association classified the taking of 'selfies' as a mental disorder?

Thu, Apr. 17th, 2014, 12:13 pm
computcomplexit: Should you reveal a P = NP algorithm?

A reader asks
What would you do if you could prove that P=NP with a time-complexity of n2 or better... moreover, would you publish it?  
There are all these statements of the good that could come of it. But how would the government react in its present state? Would it ever see the light of day? How would a person be treated if they just gave it away on the internet? Could a person be labeled a threat to national security for giving it away?
 I consider this a completely hypothetical and unlikely scenario. If you think this applies to you, make sure you truly have a working algorithm. Code it up and mint yourself some bitcoins, but not enough to notice. If you can't use your algorithm to mint a bitcoin, you don't have a working algorithm.

The next step is up to you. I believe that the positives of P v NP, like their use in curing diseases for example, greatly outweigh the negatives. I would first warn the Internet companies (like was done for heartbleed) so they can modify their systems. Then I would just publish the algorithm. Once the genie is out of the bottle everyone can use it and the government wouldn't be able to hide it.

If you can find an algorithm so can others so you should just take the credit or someone else will discover it. I don't see how one can get into trouble for revealing an algorithm you created. But you shouldn't take legal advice from this blog.

Once again though no one will take you seriously unless you really have a working algorithm. If you just tell Google you have an algorithm for NP-complete problem they will just ignore you. If you hand them their private keys then they will listen.

Thu, Apr. 17th, 2014, 10:00 am
daily_wtf: Coded Smorgasbord: Sweet Mysteries of Life

When you read a lot of bad code, you start to get a sense of why the code exists. Often, it’s ignorance- of the language, of the functional requirements, of basic logic. Sometimes, it’s...

Wed, Apr. 16th, 2014, 03:00 pm
snopes_dot_com: Poll Patrol

Has the Miami-Dade County Elections Department implemented a policy to close the bathrooms at all polling facilities?

Wed, Apr. 16th, 2014, 03:00 pm
snopes_dot_com: Drano Bottle Bombs

Warning about neighborhood residents finding unexploded 'bottle bombs' in their yards.

Wed, Apr. 16th, 2014, 03:00 pm
snopes_dot_com: Black List

Has actor Leonardo DiCaprio been tapped to portray Martin Luther King in an upcoming film?

Wed, Apr. 16th, 2014, 10:30 am
daily_wtf: Secure Development

Steven's multi-billion dollar tech firm spared no expense in providing him two computers. One was stuffed in a broom closet down the hall; he used it for email, Internet access, and other...

Tue, Apr. 15th, 2014, 03:00 pm
snopes_dot_com: Medicare at Age 76

Under Obamacare, must patients 76 and older must be admitted to the hospital by their primary care physicians in order to be covered by Medicare?

Tue, Apr. 15th, 2014, 03:00 pm
snopes_dot_com: Collapsing Currency

Will the U.S. dollar officially collapse on 1 July 2014 due to the implementation of H.R. 2847?

Tue, Apr. 15th, 2014, 03:00 pm
snopes_dot_com: Declaration of Non-Dependents

In the 1987 tax year, seven million people previously claimed as dependents on income tax returns suddenly disappeared. Where did they go?

Tue, Apr. 15th, 2014, 10:00 am
daily_wtf: CodeSOD: I Had My Reasons

Trevor spent a huge amount of time writing a 2,000,000+ PHP/JavaScript/HTML system for an e-commerce company. Like a few other I'm-Special geniuses in our field, he believed that he could do it...

Mon, Apr. 14th, 2014, 03:00 pm
snopes_dot_com: Ranch Stash

Are Senator Harry Reid and a Chinese company building a solar plant behind a standoff between federal agents and a Nevada rancher?

Mon, Apr. 14th, 2014, 03:00 pm
snopes_dot_com: Monsanto Corn

Warning about studies that have supposedly demonstrated Monsanto-developed corn contains toxins that cause organ failure in rats and adverse effects in pregnant women.

Mon, Apr. 14th, 2014, 03:00 pm
snopes_dot_com: Ringing Labelle

Was singer Patti Labelle arrested after attacking Aretha Franklin at an Atlanta concert?

Mon, Apr. 14th, 2014, 03:00 pm
snopes_dot_com: No Sale

Is the federal government preventing Volkswagen's XL1 model car from being sold in the U.S. because the vehicle is too fuel-efficient?

Mon, Apr. 14th, 2014, 10:15 am
daily_wtf: All Your RAM Are Belong to Us

Back around the turn of the century, governments were a different place to work at. The public trough, while not as fat as it had been, was still capable of providing funding for boondoggles handed...

Mon, Apr. 14th, 2014, 02:40 am
computcomplexit: Factorization in coNP- in other domains?

I had on an exam in my grad complexity course to show that the following set is in coNP

FACT = { (n,m) : there is a factor y of n with 2 \le y \le m }

The answer I was looking for was to write FACTbar (the complement) as

FACTbar = { (n,m) | (\exists p_1,...,p_L) where L \le log n
for all i \le L we have m < p_i \le n and p_i is prime (the p_i are not necc distinct)
n =p_1 p_2 ... p_L
INTUITION: Find the unique factorization and note that the none of the primes are < m
To prove this work you seem to need to use the Unique Factorization theorem and you need
that PRIMES is in NP (the fact that its in P does not help).

A student who I will call Jesse (since that is his name) didn't think to complement the set  so instead he wrote the following CORRECT answer

FACT = { (n,m) | n is NOT PRIME and forall p_1,p_2,...,p_L  where 2\le L\le log n
for all i \le L,  m< p_i \le n-1 , (p_i prime but not necc distinct).
n \ne p_1 p_2 ... p_L
(I doubt this proof that FACT is in coNP is new.)
INTUITION: show that all possible ways to multiply together numbers larger than m do not yield n,
hence n must have a factor \le m.

Here is what strikes me- Jesse's proof does not seem to use Unique Factorization.  Hence it can be used in other domains(?). Even those that do not have Unique Factorization (e.g. Z[\sqrt{-5}]. Let D= Z[\alpha_1,...,\alpha_k] where the alpha_i are algebraic. If n\in D then let N(n) be the absolute value of the sum of the coefficients (we might want to use the product of n with all of its conjugates instead, but lets not for now).

FACT = { (n,m) : n\in D, m\in NATURALS, there is a factor y in D of n with 2 \le N(y) \le m}

Is this in NP? Not obvious (to me) --- how many such y's are there.

Is this the set we care about? That is, if we knew this set is in P would factoring be in P? Not obv (to me).

I suspect FACT is in NP, though perhaps with a diff definition of N( ). What about FACTbar?
I think Jesse's approach works there, though might need  diff bound then log L.

I am (CLEARLY) not an expert here and I suspect a lot of this is known, so my real point is
that a students diff answer then you had in mind can be inspiring. And in fact I am inspired to
read Factorization: Unique and Otherwise by Weintraub which is one of many books I've been
meaning to read for a while.

Sat, Apr. 12th, 2014, 03:00 pm
snopes_dot_com: Divorce Court

Did the Hobby Lobby chain fire an employee for divorcing her husband without company approval?

Fri, Apr. 11th, 2014, 03:00 pm
snopes_dot_com: Five Million E.T. Pieces

Legend has it that in 1983, Atari disposed of millions of unsold 'E.T.' game cartridges in an Alamogordo landfill. Is that really what the company buried out in the New Mexico desert, or was it something else?

Fri, Apr. 11th, 2014, 10:05 am
scott_aaronson: Is There Anything Beyond Quantum Computing?

So I’ve written an article about the above question for PBS’s website—a sort of tl;dr version of my 2005 survey paper NP-Complete Problems and Physical Reality, but updated with new material about the simulation of quantum field theories and about AdS/CFT.  Go over there, read the article (it’s free), then come back here to talk about it if you like.  Thanks so much to Kate Becker for commissioning the article.

In other news, there’s a profile of me at MIT News (called “The Complexonaut”) that some people might find amusing.

Oh, and anyone who thinks the main reason to care about quantum computing is that, if our civilization ever manages to surmount the profound scientific and technological obstacles to building a scalable quantum computer, then that little padlock icon on your web browser would no longer represent ironclad security?  Ha ha.  Yeah, it turns out that, besides factoring integers, you can also break OpenSSL by (for example) exploiting a memory bug in C.  The main reason to care about quantum computing is, and has always been, science.

Fri, Apr. 11th, 2014, 09:45 am
daily_wtf: Error'd: Visit Scenic NON-STATIC METHOD

"I was hoping to take a trip to Hong Kong, but NON-STATIC METHOD seems to be a good value," writes Ryan.


"I had a feeling that this new laptop might run hot," Kelly L. wrote, "but I wasn't...

Thu, Apr. 10th, 2014, 03:00 pm
snopes_dot_com: Smoking Bedbugs

Are schoolkids really smoking and injecting crushed bedbugs to get high from a hallucinogenic substance they contain?

Thu, Apr. 10th, 2014, 03:00 pm
snopes_dot_com: Black Hole

Are Kansas legislators considering a bill that would force the Fox science show 'COSMOS' off the air in that state?

Thu, Apr. 10th, 2014, 10:15 am
daily_wtf: Best of Email: (Un)Helpful Support, An Epic Opportunity, and more!,-An-Epic-Opportunity,-and-more!.aspx

Don't forget, The Daily WTF loves terrible emails. If you have some to share, mail in your mail!

Perfectly Safe to Open This (from Alex)

"I mean, to some extent I'm happy to receive offers, but...

Wed, Apr. 9th, 2014, 09:24 pm
computcomplexit: Favorite Theorems: Extended Formulations

The first couple of favorite theorems took place at the beginning of the last decade, but recent years have brought exciting results as well, such as the limitations of using linear programs to solve hard problems.
It all started with a paper by E.R. "Ted" Swart (the Deolalikar of the 80's) that claimed to show P = NP by giving a polynomial-time algorithm for Traveling Salesman based on linear programming. Yannakakis put the nail in that technique by showing that no symmetric linear program formulation can solve the traveling salesman problem. The TSP problem expressed as a linear program has many facets (multi-dimensional faces) but one could possibly have a higher dimensional polytope with a smaller number of facets that could project down to the TSP polytope. Yannakakis showed that these higher dimensional symmetric polytopes must still have many facets by showing an equivalence between the smallest number of facets and the monotone dimension of a slack matrix of the polytope describing the TSP.

Not much happened since the 80's until Fiorini et al. generalized the Yannakakis result to give exponential lower bounds on the number of facets of general non-symmetric extensions of the polytope for traveling salesman. They combine Yannakakis' techniques with some communication lower bounds due to Alexander Razborov. Their approach was inspired by quantum computing ideas but in the end they had a more conventional proof.

Last fall Rothvoß showed even stronger exponential lower bounds for the matching polytope through a "substantial modification" of Razborov's work. Since matching is in P, Rothvoß showed that there are polynomial-time computable problems that can be formulated, but not succinctly formulated, as linear programs.

There has also been recent work showing lower bounds approximating clique via linear programs.

Ankur Moitra gave an excellent talk at the recent Dagstuhl giving an overview of these results and the techniques involved. The next step: Show lower bounds for semidefinite programs.

Wed, Apr. 9th, 2014, 03:00 pm
snopes_dot_com: 25 Hottest Urban Legends

The Top 25 hottest Urban Legends currently circulating.

Wed, Apr. 9th, 2014, 03:00 pm
snopes_dot_com: Drug Score

Is the NCAA investigating the use of 'skill enhancing drugs' by the 2014 champion UConn Huskies men's basketball team?

Wed, Apr. 9th, 2014, 03:00 pm
snopes_dot_com: Namesake

Account of a pregnant woman who named her child after the rescuer who died while saving her and others at the World Trade Center on 9/11.

Wed, Apr. 9th, 2014, 10:15 am
daily_wtf: CodeSOD: Exceptional Date Formatting

The Java-based application that Dan M. supports does something that is frequently accomplished by applications the world over - based on the value of a passed string containing a valid date, convert...

Tue, Apr. 8th, 2014, 10:35 pm
bradideas: Robocar Prize in India, New Vislab car

I read a lot of feeds, and there are now scores of stories about robocars every week. Almost every day a new publication gives a summary of things. Here, I want to focus on things that are truly new, rather than being comprehensive.

Mahindra “Rise” Prize

The large Indian company Mahindra has announced a $700,000 Rise prize for robocar development for India’s rather special driving challenges. Prizes have been a tremendous boost to robocar development and DARPA’s contests changed the landscape entirely. Yet after the urban challenge, DARPA declared their work was done and stopped, and in spite of various efforts to build a different prize at the X-Prize foundation, the right prize has never been clear. China has annual prizes and has done so for several years, but they get little coverage outside of China.

An Indian prize has merit because driving in India is very much different, and vastly more chaotic than most of the west. As such, western and east Asian companies are unlikely to spend a lot of effort trying to solve the special Indian problems first. It makes sense to spur Indian development, and of course there is no shortage of technical skill in India.

Many people imagine that India’s roads are so chaotic that a computer could never drive on them. There is great chaos, but it’s important to note that it’s slow chaos, not fast chaos. Being slow makes it much easier to be safe. Safety is the hard part of the problem. Figuring out just what is happening, playing subtle games of chicken — these are not trivial, but they can be solved, if the law allows it.

I say if the law allows it because Indians often pay little heed to the traffic law. A vehicle programmed to strictly obey the law will probably fail there without major changes. But the law might be rewritten to allow a robot to drive the way humans drive there, and be on an open footing. The main challenge is games of chicken. In the end, a robot will yield in a game of chicken and humans will know that and exploit it. If this makes it impossible for the robot to advance, it might be programmed to “yield without injury” in a game of chicken. This would mean randomly claiming territory from time to time, and if somebody else refuses to yield, letting them hit you, gently. The robot would use its knowledge of physics to keep the impact low enough speed to cause minor fender damage but not harm people. If at fault, the maker of the robot would have to pay, but this price in damage to property may be worthwhile if it makes the technology workable.

The reason it would make things workable is that once drivers understood that, at random, the robot will not yield (especially if it has the right-of-way) and you’re going to hit it. Yes, they might pay for the damage (if you had the right of way) but frankly that’s a big pain for most people to deal with. People might attempt insurance fraud and deliberately be hit, but they will be recorded in 3D, so they had better be sure they do it right, and don’t do it more than once.

Of course, the cars will have to yield to pedestrians, cylists and in India, cows. But so does everybody else. And if you just jump in front of a car to make it hit the brakes, it will be recording video of you, so smile.

New Vislab Car

I’ve written before about Vislab at the University of Parma. Vislab are champions of using computer vision to solve the driving problem, though their current vehicles also make use of LIDAR, and in fact they generally agree with the trade-offs I describe in my article contrasting LIDAR and cameras.

They have a new vehicle called DEEVA which features 20 cameras and 4 lasers. Like so many “not Google” projects, they have made a focus on embedding the sensors to make them not stand out from the vehicle. This continues to surprise me, because I have very high confidence that the first customers of robocars will be very keen that they not look like ordinary cars. They will want the car to stand out and tell everybody, “Hey, look, I have a robocar!” The shape of the Prius helped its sales, as well as its drag coefficient.

This is not to say there aren’t people who, when asked, will say they don’t want the car to look too strange, or who say, looking at various sensor-adorned cars, that these are clearly just lab efforts and not something coming soon to roads near you. But the real answer is neither ugly sensors nor hidden sensors, but distinctive sensors with a design flair.

More interesting is what they can do with all those cameras, and what performance levels they can reach.

I will also note that car uses QNX as its OS. QNX was created by friend I went to school with in Waterloo, and they’re now a unit of RIM/Blackberry (also created by classmates of mine.) Go UW!

Tue, Apr. 8th, 2014, 03:00 pm
snopes_dot_com: Heartbleed

The discovery of a major bug known as 'Heartbleed' has prompted web sites to encourage users to change the passwords for all of their online accounts immediately.

Tue, Apr. 8th, 2014, 03:00 pm
snopes_dot_com: Free Cone Day

Ben and Jerry's outlets are offering free ice cream on 8 April 2014.

Tue, Apr. 8th, 2014, 03:00 pm
snopes_dot_com: Pizza Spy

FBI agents holed up in a psychiatric hospital attempt to order pizzas from an incredulous delivery man.

Tue, Apr. 8th, 2014, 03:00 pm
snopes_dot_com: FDIC You

After a bank failure, does the FDIC have 99 years to pay back insured deposits?

Tue, Apr. 8th, 2014, 10:15 am
daily_wtf: Nursing the Plan Along

In the ancient time of 2008, people were still using Lotus Notes. Rumor has it that some still do, even today. Danny worked for an IBM partner which was a “full service” provider. It was...

Mon, Apr. 7th, 2014, 03:00 pm
snopes_dot_com: Bi-Bi Bieber

Has pop star Justin Bieber admitted on Twitter to being bisexual?

Mon, Apr. 7th, 2014, 03:00 pm
snopes_dot_com: Sale of the Century

Did George Zimmerman sell his painting of Trayvon Martin for $30,000 at an online auction?

Mon, Apr. 7th, 2014, 03:00 pm
snopes_dot_com: Remove Jesus Please

Photograph purportedly shows a school essay rejected because the student chose 'Jesus Christ' as her hero.

Mon, Apr. 7th, 2014, 03:00 pm
snopes_dot_com: Crest 3D White Toothpaste

Warning about Crest 3D White brand toothpaste causing plastic balls to become embedded in users' gums.

Mon, Apr. 7th, 2014, 03:00 pm
snopes_dot_com: Dwayne Johnson Death Hoax

Another clickjacking scam disguised as a celebrity death announcement: Dwayne Johnson is not dead.

Mon, Apr. 7th, 2014, 12:50 pm
computcomplexit: How free is Randomness?

Matthew Green had a great post on the topic how do you know a random number generator is working.  Gee, I just look at the sequence and see if it LOOKS random. Probably not the best idea. Actually people often found pattersn where there aren't any.

Reminds me of a the following apocryphal story which would have to have taken place before everyone had a computer: A teacher assigns the class a HW assignment to flip a coin 600 times and record H's and T's. He warns them that if they just try to come up with a random sequence without flipping he will know. Sure enough, a few of them had sequences with NO runs of 6 or more H's or T's. He knows they are faked. One of the students fessed up that yes, he just wrote down H's and T's in a way that looked random. But another student claims that he DID flip the coins, but when he saw a sequence of 6 H's in a row he changed it since he THOUGHT the teacher would spot it and THINK it wasn't random.

Is randomness a free resource? Papers in Complexity Theory strive to find good RNG's while papers in Crypto claim they already exist. Who is right?

Faulty RNG's are surely a problem for crypto protocols. But are they a problem for randomized algorithms? People really do use randomized algorithms to test primes. What other algorithms do people in the real world routinely use randomness for? (Not counting crypto protocols).Is it ever a problem?

I believe there are stories where a faulty RNG led to a crypto system being broken.

Are there stories where a faulty RNG led to a randomized algorithm being wrong?

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