علاش الصين لا تأتي؟

هاد الفيديو كا يجاوب على الدليل العقلي اللي قدمو الشيخ بندر الخيبري حول حركة الأرض وهل هي ثابتة أم في حركة.
Spoiler Alert
هاد الفكرة كا ترجع للعالم اليوناني القديم أرسطو ووضح الخطأ ديالها العالم غاليليو في بدايات الثورة العلمية.

Hi, this is Najib,

this video is about a Cheikh

claiming that the Earth is fix and not moving.

Why, because,

if the Earth was moving,

and a plane wanted to go from Ashariqa (KSA) to China;

if this plane kept static in the sky,

it is China that would come to it !
(as earth is turning)

let’s watch the video:

(Cheikh) “So the earth is static,
not moving

The logical arguments, God bless you,

we go to the Ashariqa airport,

we want to go to China,

on the plane,

clear?

stay focused:

this is earth, if you say that it is spinning,

if we take off from Ashariqa,

in an international frlight to China,

the earth is spinning, right?

Ok, if the plane stopped in the sky,

wouldn’t China come to it !?

Right or not,

China would come or not !?

Now if earth is spinning this way
(like the cup of water in his hands),

whatever the plane is doing to reach china
it will never catch it,

as China would be also following the earth
in its spinning movement.

So how would you reach China !?

(Najib) The video is longer than that,

and contained another type of arguments,

mixing up Science and religious texts.

And this is a whole issue,

but in this video,

I would like to tackle this particular part of his video.

And by the way I take the opportunity to
congratulate the Cheikh for his methodology !

The cheikh is using Nature observation,

to extract general rules of Nature.

This is at the core of Natural Sciences.

The idea this Cheikh is putting here
belongs the greek scientist Aristotle,

who lived in the fourth century BC,

and was among the natural scientist and philosophers
with the highest influence on the old world.

(map showing Alexander The great empire,
Aristotle’s student, expanding)

And it is completely normal that his ideas end up
in muslim scholars’ texts in the middle ages,

which have probably been used by our Cheikh.

Aristotle said that it is impossible
for the Earth to be spinning,

Why ?

because if it was doing so,

and if we consider someone throwing an arrow vertically,

than the arrow wouldn't be back to the same place because,
Earth would have moved in between.

The idea sounds reasonable,

and we can’t blame aristotle,

nor the old muslim scholars

or not even this Cheikh to think about it.

But the question is:

is this idea corresponding to the reality of our world?

Aristotle ideas remained accepted for
centuries all around the region,

and the first one to challenge it
and verify it was Galileo.

Galileo lived in the 17th century, in Italy.

He explained the error done by Aristotle in
a book he wrote in the late days of his life,

the book sparked a revolution in natural science.

The book was named “Discourses and Mathematical Demonstrations
Relating to Two New Sciences”.

Or simply put: “Two New Sciences”.

In this book, Galileo described the following experiment:

if we are on a moving ship

and went up to the top of the mast

to let down a pebble from above.

If Aristotle was right,

the pebble shouldn’t fall vertically to the bottom of the mast,

but should be left behind while the boat is moving forward.

Let’s figure out this by ourselves !

Today we have a ship that moves way faster
than boats of Italy in that period.

This ship is named:

...

the car !

I’m on the highway now driving at 120km/h,

if Aristotle was right,

this pebble, if thrown from the roof of the car,

while falling, the back of the car should “catch up with it”.

The pebble should either end up on the back seats,
or even break the rear windows of the car.

Let’s try !

The pebble is falling vertically in the car,

this proves that Aristotle was wrong.

Galileo proved this in detail using the concept of reference frame.

The reference frame is the place where we situate rigorously
a phenomenon before studying its mechanics.

In the reference frame of the car,

this pebble is static,

its speed is zero,

while earth and the trees outside are moving
with the speed of 120km/h in the opposite way.

While for a tree outside:

BOTH the car and the pebble are moving with a speed of 120km/h

If my car was convertible,

I would have been able to throw my pebble up higher in the air,

the movement of the pebble in the reference frame
of the car would still be vertical,

while in the reference frame of the tree,

the pebble would have a horizontale movement with a 120km/h velocity,

Seem from the latter reference frame,

its movement resembles that of a projectile,

going up and then reaching the car back.

The error made by Aristotle,

is that he was not fixing the reference frame
where he was studying the movement.

As soon as we have a clear idea
in which reference frame we are talking,

things become clear.

The plane of our Cheikh is like a butterfly,

going from the front seat (Ashariqa),

to the back seat (China).

In the reference frame of the car,

the rear seat is fix,

it is not “coming” to the butterfly.

In the reference frame of the tree,

the butterfly has already a velocity of 120km/h,

decreasing a little bit while the butterfly os going to the rear seat.

All of this is true since the car has a constant velocity.

In this case, we say that the reference frame
of the car is a Galilean reference frame.

If the velocity of the car suddenly changed,

for example if I push on my breaks,

it is no longer a Galilean reference frame,

and the poor butterfly will hit the front window.

If Earth did the same (suddenly stopped rotating),

the american scientist Neil deGrasse Tyson
explains in this video what would happen.

I can tell you that it wouldn’t be a happy event.

Now the conclusion I can draw from this story,

is that our intuition can sometimes lead us in mistake,

just like it did to Aristotle.

Intuition sometimes works, sometimes not.

The only way to figure out is to do the experiment,

just like Galileo did.

If the experimental result is not agreeing
with our initial idea,

we should accept changing our point view.

This is the scientific method !

The scientific method,

with readiness to change one’s mind in its core principles,

in which Arab scholars and philosophers played
a key role to make it precise and rigorous,

would later spark the scientific revolution in Europe,

the same scientific revolution that is still
happening all over the world.

This is it, happy experimenting, and good bye.