PHYSICS, FTW!

PHYSICS, FTW! Dmitri Krioukov, a physicist at UCSD, gets off a $400 traffic ticket by publishing a persuasive paper, “Proof of Innocence”.

Arguing in court, he explained that the officer who issued him a ticket for driving through a red light had his sense of perception deceived by combination of three circumstances which induced a physical phenomena: “if a car stops at a stop sign, an observer, e.g., a police officer, located at a certain distance perpendicular to the car trajectory, must have an illusion that the car does not stop, if the following three conditions are satisfied: (1) The observer measures not the linear but angular speed of the car; (2) The car decelerates and subsequently accelerates relatively fast; and (3) There is a short-time obstruction of the observer’s view of the car by an external object, e.g., another car, at the moment when both cars are near the stop sign.”

I love his concluding sentence, “As a result of this unfortunate coincidence, the O’s perception of reality did not properly reflect reality”. The judge must have been impressed by the graphs in his Popular Physics (free) publication: http://arxiv.org/pdf/1204.0162v1.pdf

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36 Responses to PHYSICS, FTW!

  1. Jim Tipping says:


    I love it. You rock, professor!


  2. lol, As a result of this unfortunate coincidence, the O’s perception of reality did not properly reflect reality. This is often the case, in my limited experience πŸ˜‰

  3. Rajini Rao says:


    He was quite gracious in his paper: “In summary, police officer O made a mistake, confusing the real space time trajectory of car…blah blah physics speak…However, this mistake is fully justified.. more awesome gobbledygook “. Lol.


  4. This makes my entire day πŸ˜€

  5. Rajini Rao says:


    More gems from the paper: “The author/defendant (D.K.) was driving Toyota Yaris (car C1 in the diagram), which is one of the shortest cars available on the market. Its length is l1 = 150 in. (Perhaps only the Smart Cars are shorter?) The exact model of the other car (C2) is unknown, but it was similar in length to Subaru Outback, whose exact length is l2 = 189 in.”

  6. Rich Pollett says:


    Well, his argument worked The judge was convinced, and the officer was convinced as well. His math and physical description swayed the judge, or maybe the judge was simply impressed by the sheer dedication Krioukov poured into avoiding this ticket.

  7. Norman M. says:


    The judge must have felt scientific proof is refreshing.

  8. Rajini Rao says:


    Michael Oliver M. , that is why there are points #1 and 2 preceding the obstruction excuse explanation. πŸ™‚


  9. This is hysterical (and geeky cool too of course), but I would find it even more interesting and impressive if the officer’s perceptions of reality were, in fact, accurate, and the judge was snowed because he didn’t understand the explanation and then assumed it must be true. (Note to non-scientists: understanding science and methodology is important.)

  10. Rajini Rao says:


    Although we may have a sneaky suspicion that O’s perception matched reality, unless this thesis is disproved, it could well be true πŸ™‚

  11. Rich Pollett says:


    Also remember the paper was published on April Fool’s Day.

  12. Rajini Rao says:


    Good Catch, Rich Pollett ! This story is getting better πŸ™‚

  13. Rajini Rao says:


    The published article is from Physics Central, on the arXiv server. I found this exchange on a physics blog, “I noticed that the paper was posted on April Fool’s Day, so it definitely seemed a little fishy. When I spoke with Krioukov over the phone, however, he seemed to provide a few details about the court case that made the story sound quite plausible.”. The LA times published an interview with Krioukov today, so it would certainly be odd for a Fool’s Day prank to be dragged out so long. See: http://latimesblogs.latimes.com/lanow/2012/04/ucsd-scientist-evades-400-traffic-ticket-with-research-paper-.html


    Curiouser and curiouser πŸ™‚

  14. Rajini Rao says:


    Rich Pollett , the paper is also listed on Krioukov’s academic website at UCSD: http://www.caida.org/~dima/pub/index.html

  15. Rich Pollett says:


    The Proof of Innocence. “Physics works!” β€” Walter Lewin πŸ™‚

  16. Rajini Rao says:


    Apparently, Krioukov has a challenge for his readers: “I want to ask the readership to please find the flaw in the argument.” πŸ™‚


    See various hypotheses here: http://physicsbuzz.physicscentral.com/2012/04/physicist-uses-math-to-beat-traffic.html

  17. Rajini Rao says:


    Roman Shcherbakov , seems legit so far, but who knows? These physicists can be tricky πŸ˜‰

  18. Rajini Rao says:


    Good morning, Feisal Kamil .


    I love that site (including the club for luxurious hair in scientists) πŸ™‚ Hey, I did find this paper listed on Discoblog as well: http://blogs.discovermagazine.com/discoblog/

  19. Rajini Rao says:


    Gnotic Pasta , I did win an argument in traffic court over an alleged red light stop. The funny part of the whole thing was when the judge asked the police officer what his side of the story was, the guy said, “She argued with me”! Huh? I could see my husband lol’ing over this (in that case, I would get tickets all the time).

  20. Rajini Rao says:


    What’s the story with Andre Geim?

  21. Rajini Rao says:


    No fair, Gnotic Pasta ! That’s what I was trying to do, except that the officer got it into his head that I had attitude (who, moi?) and gave me a ticket.


    Feisal Kamil , this is what I found: http://www.improbable.com/2010/10/05/geim-becomes-first-nobel-ig-nobel-winner/

  22. Rajini Rao says:


    Wow, I remember the graphene Nobel and the levitating frog IgNobel but never put them together. Thanks, Roman Shcherbakov πŸ™‚

  23. Rajini Rao says:


    What ace, Dan? I won’t tell anyone else πŸ™‚ Feisal Kamil , that’s why we need to see those college pics that you pretend are missing!

  24. Rajini Rao says:


    Ahh, you had on your uniform didn’t you!! πŸ™‚

  25. Rajini Rao says:


    Nicely done! No physics paper needed πŸ™‚

  26. Yohan Wadia says:


    Wish i could do that each time i get caught breaking a signal.. πŸ™‚

  27. Rajini Rao says:


    Tsk, tsk Yohan Wadia . How many times have you broken a traffic law? πŸ™‚

  28. Rajini Rao says:


    Does it involve an afro? πŸ™‚

  29. Yohan Wadia says:


    last time i checked… atleast four times.. but hey.. its Mumbai.. peak traffic hours.. what else can i do?? πŸ˜›


    PS: i would also like to point out that i was caught only once out of the four times πŸ˜€


  30. My solution? Don’t drive cars.


    I lived in a place once where I had to have a car. My home was far enough from my work, but my boyfriend’s was even farther. So when I stayed overnight at his place, I would be in a mad dash to get to work on time so one bleary morning I speeded (a bit).


    I had just happen to read the previous day about how to handle getting speeding tickets which is basically to admit you were speeding and to give no excuses. I did that and then the officer wrote out the ticket very solemnly matching my own solemness. When finished he gave a funny twist to his mouth (think it was a smile) and said, because of your honesty I marked your transgression in the lower speeding zone, therefore lessening the cost of your ticket by half. Trying not to laugh, I thanked him and slowly drove away (at half speed).


  31. I would SO love to live somewhere where I didn’t need a car! Sadly, southern California ain’t it.


  32. Flawless physics but idiosyncratic syntax: “… induced a physical phenomena” (sic).

  33. Rajini Rao says:


    John Condliffe , English is not this author’s native language. I caught several errors in the reading of his paper, even fixed a couple in my quotes above.

  34. Rajini Rao says:


    Thanks to Rhett Allain for linking to this post with very useful animations of this guy’s arguments (and flaws, as well). http://www.wired.com/wiredscience/2012/04/an-analysis-of-the-stopping-car-analysis/


    FYI, Rich Pollett , Roman Shcherbakov , Koen De Paus

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