They Shook the Earth!

It happened that I encountered some people who were obsessed with questions about jumping together.  The favorite scenario was about gathering all the people on earth and then asked them to jump together.  They wanted to know whether the earth would be moved by such momentum.  Some went further and thought that the rotation of the earth, or even the orbit of its revolution around the sun would be affected.

We tended to brush such question off by some common sense arguments.  It was impossible to gather so many people together.  They needed to be in a relatively small area so as to focus the momentum and not to have the forces cancelled out each other.  Not only that those people needed to synchronize in jumping up, it would be more important for them to land at the same time.  The list could go on forever without attacking the question head on.

However, some scientists, maybe influenced by the famous thought experiments of Einstein, took the question seriously.  Randall Munroe in his blog (what-if.xkcd.com) and then his book (What If?: Serious Scientific Answers to Absurd Hypothetical Questions) defined the question: What would happen if everyone on earth stood as close to each other as they could and jumped, everyone landing on the ground at the same instant?  In a site which claimed to fight ignorance since 1973 (straighdope.com), a similar question was post as early as 1986, and it involved Chinese: If every man, woman, and child in China each stood on a chair, and everyone jumped off their chair at exactly the same time, would the earth be thrown off its axis?  In scienceblog.com, a blogger did some calculation taking into account the mass of the earth, the mass of all the people on earth, the gravitational field, the height that people jumped, velocity of the earth, action and reaction forces.  As I did not understand the calculation, I could only tell you the simplified result was that there would not be any detectable effect.  The main reason was that the mass of the earth outweighed the mass of the total population by a factor of over ten trillion.

Randall Munroe chose to go into more details of the jumping experiment.  He assumed that all people really gathered in Rhode Island, as he figured that it needed an area the size of Rhode Island to accommodate all the people on earth.  He came to the same conclusion that the earth would not be moved, though he added that there would be a loud sound resulted from the synchronized landing of so many people.  Then came his further analysis.  There would be no signals for mobile phones.  The people found it very difficult to leave either by plane, by train or by car.  People did not speak a common language.  There were insufficient food and water supply.

In October 2016, 19 doctors planned to shake the earth.  They formed an alliance and got started to take part in the Medical Subsector Election of the Election Committee.  They formulated a seemingly unrealistic goal of getting all 19 members into the Election Committee.  They vowed to change the Chief Executive and to change the system of election of the Chief Executive and Members of the Legislative Council.  Their causes were shared by pro-democratics of other subsectors.  There was actually a bigger alliance which aimed at getting more than 300 votes in the Chief Executive election.  At the same time, there was a shared common platform among the majority of all candidates for the election: the Chief Executive had to be changed.

Then, at 3:30pm December 9, 2016, the earth stopped spinning for a fraction of a split second.  While Hong Kong people were gloomy about their fate, the Chief Executive, CY, announced that he would not go for another 5 years.  Before those guys started to jump, their mere gathering had shown power.  Statistics clearly showed that the coming Election Committee would not favor the present Chief Executive to continue his heroic acts.  CY got his red light.

I felt the earth shaking on December 12, 2016 when the results of the Election Committee were announced.  All the 19 doctors were elected.  And they were not alone.  Whole cabinets were elected in many other subsectors for the bigger alliance.  Having the whole cabinet elected was quite historical in elections of the medical profession.  The 19 doctors were different in weight.  Their abilities to jump differed.  They even did not synchronize to start jumping.  However, most importantly, they were able to land together perfectly and delivered their unified force.  They had clear and admirable causes.  They had strategies, energy and discipline to execute.  Voters were moved by their enthusiasm.  All the members got similar number of over 3000 votes.  This clearly reflected that voters supported the team as a whole.

At the same time, when they landed, they delivered a unified and resonating voice.  It was clearly heard.

They really shook the earth!

(Source: HKMA News December 2016)