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Why SpaceX Won't Turn Us Into A Multi-planetary Species

Anyone announcing the successful sale of tourist trips around the moon would attract ridicule and...

Rational Suckers

Why do people skip queues, cause traffic jams, and create delays for everyone? Who are these misbehaving ...

Triple Or Bust: Paradox Resolved

A few days ago I discussed the coin toss game ‘triple or bust‘. The game is between Alice and...

Paradox: Triple Or Bust

Today I have a decision problem for you....

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Johannes KoelmanRSS Feed of this column.

I am a Dutchman, currently living in India. Following a PhD in theoretical physics (spin-polarized quantum systems*) I entered a Global Fortune 500 company where I am currently Chief Scientist

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The King of Recreational Math Is No More

The King of Recreational Math Is No More

May 23 2010 | comment(s)

Martin Gardner died yesterday. His memory will live on through some 70+ books and, above all, through his column "MATHEMATICAL GAMES" in Scientific American. During the 25 years that Gardner's column appeared, it was probably for many amongst the SciAm readers the main reason to buy a copy each month.

Via "MATHEMATICAL GAMES" , Martin Gardner made the wonders of math known to the layperson. For an example see this 40 (!) year old column introducing ''The Game of Life" to the masses.

You, Retaliator!

You, Retaliator!

May 16 2010 | comment(s)

The safe deposit in front of you is wide open. Twenty stacks of one-hundred dollar bills stare you in the face. Each stack a hundred bills thick. So many Benjamins. All for Jude, the other remaining contestant. That is... provided you don't touch the money.

You prepared yourself a zillion times. Still it feels like you are placed in an entirely new situation, a nightmare you never considered.
Hubble's 20th: A Taxpayer's Perspective

Hubble's 20th: A Taxpayer's Perspective

Apr 23 2010 | comment(s)

Hip, hip, hooray. The Hubble has reached its twentieth anniversary* and is  still alive and kicking. Congratulations go to NASA and ESA. And to the Hubble itself. Long live the Hubble!

Chances are, that by now you will be able to read more than a few blogs hailing the two decades of the Hubble as mankind's supreme window to the universe. And indeed, the Hubble has provided us with some spectacular pictures of the universe.

Shut Down The LHC? I'd Rather Not Hurt A Fly

Shut Down The LHC? I'd Rather Not Hurt A Fly

Mar 30 2010 | comment(s)

So how dangerous is the Large Hadron Collider? How likely is it that when operated at maximum energy the LHC will create a black hole and wipe out earth? Eric Johnson, assistant professor of law at the University of North Dakota and author of the report The Black Hole Case: The Injunction Against The End Of The World, writes in a recent edition of New Scientist:
It From Bit - Entropic Gravity For Pedestrians

It From Bit - Entropic Gravity For Pedestrians

Mar 26 2010 | comment(s)

Two and a half months since Erik Verlinde submitted his entropic gravity paper, and all of physics and cosmology has turned into entropy. Well, I am exaggerating a bit, and perhaps more than just a bit. Yet, fact is that within two weeks of Erik's publication a steady stream of 'entropic everything' papers has developed at a rate of close to one paper per day. Gravity, Einstein's equations, cosmic expansion, dark energy, primordial inflation, dark mass: it's all entropic. Chaos rules.

Big Bang, Big Bewilderment

Big Bang, Big Bewilderment

Feb 25 2010 | comment(s)

We live in an expanding universe. Distant galaxies move away from us, and these galaxies see us moving away from them. If we reverse time and trace back this expansion, it follows that the universe has evolved from a dense primeval/primordial state.

The big bang concept summarized in three sentences.

Sounds easy?