I’ve been reading voraciously. Latest books have included “Cicero, selected political speeches”, “Ghandi, an autobiography” and numerous humour, murder mystery and SciFi books.

This thread is about “Einstein’s theory of relativity” by Max Born (1924), which I’ve now started reading.
This book begs a comparison with “Relativity and common sense” by Hermann Bondi (1964).

Both books are aimed at the high school market. There’s mathematics in both, but nothing more difficult than elementary algebra and geometry (similar triangles and Pythagorus). You don’t need either calculus or trigonometry to read either, so both books can be read by Year 11 high school students.

Bondi’s approach is to bounce light waves back and forth. Time dilation comes from changes in frequency of those light waves. Distance is detewrmined using radar. The book derives all of special relativity using only the assumption of a constant value for c, the speed of light. The book requires no familiarity with Newtonian Physics, and stops with special relativity and a proof of E=MC^2 from special relativity. I learnt about special relativity from Bondi’s book.

A slight digression here to the book “Subtle is the lord – the science and life of Albert Einstein” by Abraham Pais (1982) has a terrible title. but is the best introduction to Gneral Relativity that I know. For the maths it helps to know what a partial differential looks like, or you can just skip the maths and enjoy the biography.

Max Born’s book was written 40 years earlier.
It starts very basic. What is length, what is time, geographic latitude and longitude, coordinates. That fills chapter 1.

Ch 2. “the unit of weight today is the weight of a definite piece of platinum held in Paris. This unit, called the pond (p) …”
In chapter 2 he defines force, elastic, action = reaction. He defines velocity, acceleration, and gets as far as uniform circular motion proving that acceleration = v^2/r. Inertia, impulse. He defines mass as impulse divided by velocity. (ie. inertial mass) and mentions momentum and proves that force = mass times acceleration (which he writes in archaic notation as K=mb). Elastic vibration. The equivalence and non-equivalence of weight and mass – a beam balance measures mass wherever you are on the surface of the Earth but a spring balance does not. Conservation of energy. Units of force and mass.

In other words, Born’s book in simple steps moves up from “length is measured in metres, time is measured in seconds” to the laws of Newton.

Ch 3 introduces us to linear motion as viewed by a rotating observer, gravity, Kepler, centrifugal force, Foucalt’s pendulum.

Ch 4 introduces us to optics, waves, the velocity of light.
Unlike Bondi who just assumes that the speed of light is a constant, Born gives the clearest explanation of how we know that speed of light is a constant, by observations of the moons of Jupiter.

By chapter 5, page 146, we get to electrodynamics.

Max Born works slowly, methodically, in easy mathematics and physics all the way up to Special Relativity and finally General Relativity. It’s just like a good textbook, with plenty of worked examples and plenty of figures (all simplified diagrams). It leaves out nothing of importance and includes everything necessary.

So if you want to learn all about relativity without learning calculus or trigonometry first, Max Born’s (1924) “Einstein’s Theory of Relativity” is the way to go. I’m reading the 1962 edition.

Thanks for that.

I haven’t read any physics books for ages. Might get back into it one day but I’m seldom in that sort of mood these days.

Bubblecar said:

Thanks for that.

I haven’t read any physics books for ages. Might get back into it one day but I’m seldom in that sort of mood these days.

Same here, very nice review.

I do read modern physics books from time to time (pop-science level), but I’m tempted to read some older stuff.

Did you get from an on-line library or buy the old-fashioned books?

The Rev Dodgson said:

Bubblecar said:

Thanks for that.

I haven’t read any physics books for ages. Might get back into it one day but I’m seldom in that sort of mood these days.

Same here, very nice review.

I do read modern physics books from time to time (pop-science level), but I’m tempted to read some older stuff.

Did you get from an on-line library or buy the old-fashioned books?

This is a book I inherited when step-dad died. You may be interested to know that stepdad was a civil engineer in NSW main roads, worked in Broken Hill, Wollongong and with the bigwigs in Sydney. You may even have heard of him.

Page 211 of the Max Born book has me questioning the fundamentals of physics all over again (oh dear). The quote is:

“The idea occurs that the electron has, perhaps, no “ordinary” mass at all, but this mass is entirely electromagnetic in origin”.

We know that the photon as no ordinary mass at all, and gets its mass-energy entirely from electromagnetism. But the electron !?

Born goes on the calculate the radius of the electron if all it’s mass comes from the energy of electric charge repulsion. The radius comes to 1.88e-13 cm.

How does that compare with the classical radius of an electron? The current value of the classical radius of the electron is 2.818e-13 cm, good agreement considering that the above calculation was done back in the year 1924.

So if the electron doesn’t have any ordinary mass, what does that tell us about other subatomic particles? The muon, the neutrino.
How does the classical radius of the electron tie in with electron spin?
Can be get a predicted mass for the neutrino in a similar way?

And why doesn’t an electron blow itself apart, having mutual repulsion of the charge but neither ordinary mass nor W, Z particles nor the strong force to tie it together?

The questions keep multiplying.

mollwollfumble said:

The Rev Dodgson said:

Bubblecar said:

Thanks for that.

I haven’t read any physics books for ages. Might get back into it one day but I’m seldom in that sort of mood these days.

Same here, very nice review.

I do read modern physics books from time to time (pop-science level), but I’m tempted to read some older stuff.

Did you get from an on-line library or buy the old-fashioned books?

This is a book I inherited when step-dad died. You may be interested to know that stepdad was a civil engineer in NSW main roads, worked in Broken Hill, Wollongong and with the bigwigs in Sydney. You may even have heard of him.

Quite likely. Can you give us a name?