We’re thinking at the wrong things

Written on 20 May 2016, 02:44pm

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It seems like we, humans, have the strange ability to worry about little things and to procrastinate or ignore the big, important ones. NN Taleb explains this in his essay ‘The Black Swan’:

What are our minds made for? It looks as if we have the wrong user’s manual. Our minds do not seem made to think and introspect; if they were, things would be easier for us today, but then we would not be here today and I would not have been here to talk about it—my counterfactual, introspective, and hard-thinking ancestor would have been eaten by a lion while his nonthinking but faster-reacting cousin would have run for cover. Consider that thinking is time-consuming and generally a great waste of energy, that our predecessors spent more than a hundred million years as nonthinking mammals and that in the blip in our history during which we have used our brain we have used it on subjects too peripheral to matter. Evidence shows that we do much less thinking than we believe we do—except, of course, when we think about it.
Nassim Nicholas Taleb: The Black Swan – The Impact of the Highly Improbable

Exhibit A: Superbugs

Superbugs will kill someone every three seconds by 2050 unless the world acts now, a hugely influential report says.
A global revolution in the use of antimicrobials is needed, according to a government backed report.
Lord Jim O’Neill, who led the Review on Antimicrobial Resistance, said a campaign was needed to stop people treating antibiotics like sweets.
It is the first recommendation in the global plan for preventing medicine “being cast back into the dark ages”.
The report has received a mixed response with some concerned that it does not go far enough.
Superbugs, resistant to antimicrobials, are estimated to account for 700,000 deaths each year.
But modelling up to the year 2050, by Rand Europe and auditors KPMG, suggests 10 million people could die each year – equivalent to one every three seconds.
BBC: Global antibiotics ‘revolution’ needed

Exhibit B: Climate change

In spite of reports, evidence, climate refugees and general consensus in the science world that climate change is starting to affect our lifes, there are still top level politicians arguing that everything is just ‘peer-pressure’ and that ‘everybody is a scientist’:

Ex-Alaska governor promotes Climate Hustle film and calls for intervention to stop the ‘peer pressure’ as world leaders agree global warming is a serious threat.
The former vice-presidential nominee admitted she did not believe scientists about anything any more – and appealed to presidential contenders to intervene, somehow.
The Guardian – Climate change denier Sarah Palin: ‘Bill Nye is as much a scientist as I am’

As a side note, there is a nice response to the statement above.
But unfortunately, we’re doing very little to fight climate change. Hopefully it won’t be too late.

Exhibit C: Colonizing other worlds

I don’t think the human race will survive the next thousand years, unless we spread into space (Stephen Hawking)
We should do it soon, because colonizing other worlds is our best chance to hedge our bets and improve the survival prospects of our species. Sooner or later something will get us if we stay on one planet. (Princeton professor J. Richard Gott)
In the long run a single-planet species will not survive (Nasa Administrator Michael Griffin)

Apparently, in this case at least, someone is thinking big. There is hope 🙂

black swan

Weekly links

Written on 5 October 2015, 02:43pm

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Inaugurating a new post type – a collection of links to interesting articles/stories. Aimed to be updated weekly 🙂

“If a gravitational wave were to pass through you now, this ripple in spacetime would stretch you taller and thinner, then squash you shorter and fatter. The reason you wouldn’t notice is because your height would be altered by less than the width of a proton (a fraction of the size of an atom).”
Cosmos Magazine – Einstein’s gravitational waves remain elusive

Every picture ever made during the Apollo moon missions has been made available on Flickr through the Project Apollo Archive.
Washington Post – Over 9,000 Apollo moon mission pictures are now online

“All of these feature were built for one reason — a self driving future combined with an entire self-driving mobility platform. The Model X was built to be either the ultimate self-driving taxi, or the ultimate human/self-driving rental car — or both.”
Gavin Sheridan – Elon Musk’s sleight of hand

Time dilation

Written on 7 August 2015, 02:47pm

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The passing of time can be altered by 2 factors, gravity and velocity.
Increase in both gravity or velocity will slow down time.
1. Gravity: Everything likes to live where it will age the most slowly, and gravity pulls it there (Kip Thorne – the Science of Interstellar)
2. Velocity: A space traveler approaching the speed of light will age slower than another one staying on the earth (Twin paradox).
What does this mean?

On the ISS, time runs slower because of the high speed

Altitude: about 400km
Orbital speed: 8km/s
Time dilation: 0.01 seconds slower every year
The smaller gravity pull from the Earth accelerates the time, but not enough to compensate for the velocity of 8km/s which slows down time. So in the end, an astronaut spending 6 months on the ISS will be about 0.005 seconds younger.

[On the ISS] Velocity has increased for the astronauts, slowing down their time, whereas gravity has decreased, speeding up time (the astronauts are experiencing less gravity than on Earth). Nevertheless, the ISS astronaut crew ultimately end up with “slower” time because the two opposing effects are not equally strong. The velocity time dilation is making a bigger difference, and slowing down time. The (time-speeding up) effects of low-gravity would not cancel out these (time-slowing down) effects of velocity unless the ISS orbited much farther from Earth.

On the GPS satellites, time runs faster because of the decrease of gravity

Altitude: 20.000km
Orbital speed: 4km/s
Time dilation due to velocity: 7 microseconds per day
Time dilation due to less gravity: 45 microseconds per day

The combination of these two relativistic effects means that the clocks on-board each satellite should tick faster than identical clocks on the ground by about 38 microseconds per day (45-7=38)! This sounds small, but the high-precision required of the GPS system requires nanosecond accuracy, and 38 microseconds is 38,000 nanoseconds. If these effects were not properly taken into account, a navigational fix based on the GPS constellation would be false after only 2 minutes.
The engineers who designed the GPS system included these relativistic effects when they designed and deployed the system.
GPS and relativity
[Contrary to popular belief, GPS satellites are not in geosynchronous or geostationary orbits). The satellite orbits are distributed so that at least 4 satellites are always visible from any point on the Earth at any given instant (with up to 12 visible at one time)]

Inspired by: The Science of ‘Interstellar’ Explained (Infographic)