## Monday, April 17, 2023

### How geometry created modern physics

Here is an elementary new lecture:
How geometry created modern physics – with Yang-Hui He

The Royal Institution

2,019 views Apr 13, 2023 THE ROYAL INSTITUTION

What's the story behind the five axioms of Euclidean geometry - and how is post-Euclidean geometry linked to modern physics?

From geometry’s classical beginnings, via the Renaissance and the Enlightenment, to the present day, Yang-Hui He takes us on a journey through time and space, culminating in our understanding of spacetime itself. In the 19th century, mathematicians such as Carl Gauss and Bernhard Riemann considered what would happen if we relaxed Euclid’s axioms. The result was the explosion of post-Euclidean geometry, which paved the way for Einstein’s theory of relativity and the birth of modern physics.

Here is the Q & A.

It is a nice expository lecture. It makes me wonder if modern Physics would have even been created, if not for Euclid's Elements. He says it is the most read book ever written, next to the Bible.

Historically, I wonder who first realized that XX century Physics was so dependent on geometry. Surely Hermann Weyl understood it a century ago. Einstein did not accept it, and particle physicists of the 1960s were slow to accept it.

Eventually the theorists were taken over by string theorists who want to do everything with geometry.

#### 1 comment:

1. String theorists wanted degrees of freedom they couldn't assign to size-less points with their very poorly assigned math to carry forces. So they extended the points, and Voila, String Theory.

Now respectable scientists and physicists can pretend that indestructible timeless indivisible line segments can be elastic, bend, tangle, vibrate, and loop in one dimension... as if they didn't know what the hell those kind of movements would require structurely and mechanically...namely that one dimensional objects
A.) Don't exist outside of geometric abstraction,
B.) Can't bend in one dimension,
C.) Can't loop in one dimension,
D) Certainly can't vibrate in one dimension
E.) Sure as hell can't interact with other said segments one dimensionally,

and F. (for FAIL apparently)) Can't do any of these things outside of time which would require yet another dimension to be tacked on to the ever so precious one dimensional line segments and their interactions requiring movement in three dimensions.

I'm really not quite certain why physicists don't openly say they believe in magic...Since they evidently employ contradictions and miracles so frequently to make their theories go.