Explore the mysteries of quantum mechanics, black holes, strings, branes, supersymmetry, and extra dimensions.
In this engaging and concise introduction to the main ideas in string theory, Steven Gubser gives a quick tour of the basic laws of physics as we understand them today. And then, he demonstrates how string theory seeks to go beyond them.
Steven S. Gubser is a professor of physics at Princeton University. His research focuses on theoretical particle physics, especially string theory, and the AdS/CFT correspondence. He is a widely cited scholar in these and other related areas.
After receiving a Ph.D. in 1998 from Princeton, Gubser did postdoctoral research at Harvard University before taking a position as an assistant professor at Princeton. In 2001, he moved to the California Institute of Technology but returned again to Princeton in 2002.
As a high schooler, he was the first American to win the International Physics Olympiad, in 1989. He was also a silver medalist at the 1990 International Chemistry Olympiad.
Any of a number of theories in particle physics that treat elementary particles (seesubatomic particle) as infinitesimal one-dimensional stringlike objects rather than dimensionless points in space-time. Different vibrations of the strings correspond to different particles. Introduced in the early 1970s in attempts to describe the strong force, string theories became popular in the 1980s when it was shown that they might provide a fully self-consistent quantum field theory that could describe gravitation as well as the weak, strong, and electromagnetic forces. The development of a unified quantum field theory is a major goal in theoretical particle physics, but inclusion of gravity usually leads to difficult problems with infinite quantities in the calculations. The most self-consistent string theories propose 11 dimensions; 4 correspond to the 3 ordinary spatial dimensions and time, while the rest are curled up and not perceptible.
- Hallelujah !! String Theory !!
Science has always been a source of heresy.
Lee Smolin wrote:
I have written this book in the hope that it will contribute
to an honest and useful discussion among experts and
lay readers alike.
/ ‘ The trouble with Physics’. Page XVIII. /
I will take Smolin’s proposition and try to explain my
amateur’s thoughts about that was called ‘String theory’.
Three years ago I posted an article ‘ The Special Theory
of Relativity’ I wrote:
‘ String theory acts in 11- D space.
But if we don't know what 1+1 = 2 is
how can we know what 5+4 = 9 is?
And if we don't know what 4-D negative Mincowski space
is how can we understand 11-D space ( String theory) ?’
I wrote: . . . .
‘If I were a king, I would publish a law:
every physicist who takes part in the creation
of 4D space and higher is to be awarded a medal
"To the winner over common sense".
Because they have won us using the
absurd ideas of Minkowski and Kaluza. ‘
This was a reason that I refused to read any information
about ‘String theory’.
And later on different forums I posted emails, trying
to explain, that the point is only a shadow of real particle,
that it is impossible to understand Physics and Nature
thinking of particle as a point.
I wrote: In 1915 Einstein connected Mass with Geometry.
Maybe now, in 2010, somebody will try to understand the
interaction between an elementary particle and geometry.
If physicists think about a particle as a " mathematical point"
the result can be only paradoxical. And I am sure if somebody
takes into consideration the geometrical form of particle
the paradoxes in Physics will disappear.
Travelling in Scotland, by chance, in a secondhand shop
I bought a book: ‘ The trouble with Physics’ by Lee Smolin.
This book changed my opinion about ‘String theory’.
Now I say: Hallelujah ! Hallelujah ! Why? Because
‘… particles could not be seen as points, which is how
they always been seen before. Instead, they were ‘stringlike’,
existing only in a single dimension, and could be stretched, . .
And . . . they vibrated.’ / Page 103. / ‘ . . the idea of particles
as vibrations of strings was the missing link that could work
powerfully to resolve many open problems.’ / Page 124./
It is nice. It is pleasant to read this idea.
So, the string particle is a dynamic particle. And the string can
have different geometric forms: ‘String can be both closed and
open. A closed string is a loop. An open string is a line;
it has ends’. / Page 106./ And now few physicists try to connect
forces, movement and geometry of the quantum particle together.
Hallelujah ! It is a progress. It is a step to truth.
Now I say: the truth is hidden in the ‘ String theory ’.
But there are many string theories. And the growing catalogue
of string theories evokes trouble. Because one theory is better
than the other one, but at the same time each new theory brings
new problems. Maybe therefore Lee Smolin wrote:
‘ . . . at least one big idea is missing.
How do we find that missing idea?’ / Page 308. /
Interesting: What was missed by ‘ the brightest and
best- educated scientists’ who worked very hard doing
many complicated calculations ?
New particle? New D ? New force? New idea?
Where did they have an error?
I will try to understand this situation.
If I were professor I would great super – super 55D for
explaining everything. But I am a peasant and the best way
for me is to take the simplest reference frame – the Euclidean
space ( 2D) . And maybe (who knows ?) Newton was right
saying: ‘ Truth is ever to be found in simplicity,
and not in the multiplicity and confusion of things.’
Now I will put a virtual- ideal particle in this 2D.
The 2D is a thin and flat homogeneous space, so my particle
also must be thin and flat and very symmetrical.
Can it be a very thin and tiny limited line- string?
No. In my opinion even this very thin and tiny line
under good microscope will be looked as a rectangle.
Can it be a very thin and tiny limited loop?
No. The geometrical form of a loop is too complex,
needs supplementary forces to create it.
Can it be a very thin and tiny limited circle?
From all geometrical forms the circle is the most symmetrical.
The surface of a circle takes up the minimal area it can and
I will write it by formula: C/D= pi= 3.14. (!)
But I can put many particles there, for example,
Avogadro’s number of particles: N(a). (!)
What is my next step?
If I were a physicist I would say that 2D must have some
physical parameters like: volume (V), temperature (T)
and density (P). Yes, it seems the idea is right.
Then, volume (V) is zero,
temperature (T) is zero
but . . but density (P) cannot be zero if 2D is a real space
then its density can approximately be zero.
What can I do with these three parameters?
I have only one possibility, to write the simplest formula:
VP/T=R (Clapeyron formula !)
What is R? R is some kind of physical state of my 2D.
And if I divide the whole space R by Avogadro’s
numbers of particles then I have a formula R/ N(a) = k,
then k ( as a Boltzmann constant) is some kind of
physical state of one single virtual- ideal particle. (!)
But all creators of Quantum theory said that this space,
as a whole, must have some kind of background energy (E).
And its value must be enormous.
But the background mass of every Avogadro’s particles
in 2D has approximately zero mass, it is approximately
So, if I divide enormous energy (E) by approximately
massless (M) then the potential energy/ mass of every single
virtual- ideal particle ( according Einstein and Dirac) is
E/M=c^2 (potential energy/mass E/M=c^2 ! )
( I don’t know why physicists call E/M= c^2 ‘rest mass’
and never say potential energy/mass E/M=c^2 .)
In potential state my particle doesn’t move,
so its impulse is h = 0.
I have virtual- ideal- massless particle which has
geometrical and physical parameters:
C/D= pi= 3.14 . . . . , R/ N(a) = k, E/M=c^2, h=0.
All my virtual- ideal- massless particles are possible to call
‘ bosons’ or ‘antiparticles’ . These bosons are approximately
massless but have huge potential energy/mass E/M=c^2 .
But I have no fermions, no electric charge, no tachyons,
no time, no mass, no movement at this picture.
Smolin wrote: ‘ – the missing element – must have been
one of the earliest triumphs of abstract thinking.’/page 102/
Where was ‘the earliest triumphs of abstract thinking.’?
In the hope to understand Smolin’s thought I will draw
historical scheme: Quantum Theory ---->
----> Thermodynamics ----> Theory of gases ----> Ideal Gas.
So, ‘the earliest triumphs of abstract thinking.’ was connected
with idea of an ‘Ideal Gas’. From Ideal Gas our trouble with
physics begins. I think the ‘Ideal Gas’ cannot be an abstract
hypothesis. In my opinion the ‘Ideal Gas’ must be a real model
of vacuum: T=0K . We can use all laws of ‘Ideal Gas’ for
explaining the situation in Vacuum: T=0K.
Now, thinking logically, I must explain all the effects of
motions. And. . . and I cannot say it better than Newton:
‘For the basic problem of philosophy seems to be to discover
the forces of nature from the phenomena of motions
and then to demonstrate the other phenomena from these forces.’
How can one single virtual- ideal particle start its movement?
At first, it will be right to think about some simple kind of
movement, for example: my particle will move in straight line
along 2D surface from some point A to the point B.
What is possible to say now?
According to the Michelson-Morley experiment my particle
must move with constant speed: c=1 and its speed is independent.
Its speed doesn’t depend on any other object or subject, it means
the reason of its speed is hidden in itself, it is its inner impulse.
This impulse doesn’t come from any formulas or equations.
And when Planck introduced this inner impulse(h) to physicists,
he took it from heaven, from ceiling. Sorry. Sorry.
I must write: Planck introduced this inner impulse (h) intuitively.
I must write: Planck introduced his unit (h) phenomenologically.
At any way, having Planck’s inner impulse (unit h=1) my
particle flies with speed c=1. We call it photon now.
Photon’s movement from some point A to the point B
doesn’t change the flat and homogeneous 2D surface.
Of course, my photon must be careful, because in some local
place some sun’s gravitation can catch and change its trajectory
I hope it will be lucky to escape from the sun’s gravity love.
My photon can have other possibility to move. This second
possibility was discover by Goudsmit and Uhlenbeck
in 1925. They said the elementary particle can rotate
around its diameter using its own angular inner impulse:
h * = h /2pi. So, when photon rotates around its diameter
it looks like a string ( open string) and this string vibrates.
My god, that is a strange technical terminology the physicists
use: ‘ vibrate, vibration’.
If I were a physicist I would say no ‘ vibrate, vibration’ but
‘ frequency’, ‘the particle rotates with high frequency’.
The frequency is a key to every particle, by frequency we know
the radiation spectrum of various kinds of waves.
Now I can say: then my photon starts to curl its rotation
goes with enormous frequency, faster than constant speed
of photon. Now its speed is c>1. We call it ‘tachyon’.
The tachyon’s spinning creates electric charge and
electrical waves and now we call it ‘electron’ or ‘fermions’.
So, in my opinion, virtual- ideal particle, photon, tachyon
and electron are only different names of one and the same
particle – quantum of light.
The frequency of every string particle can change.
( The various states of vibration . . . Page 103.)
The geometrical form of string can change.
( When they gained energy, they stretched; when they
gave up energy, they contracted - Page 103.)
Thanks to rotating movement the ‘massless’ of particles
increased and it became real observed particle.
Stop ! !!
I have missed here something important.
What have I missed?
( When they gained energy, they stretched; when they
gave up energy, they contracted - Page 103.)
What does it mean? What did Smolin want to say?
How can I understand this process ?
. . . . . . . . . . .
My particle is a circle. When this circle started to curl around
itself its form changed. Now it has volume and looks like a sphere.
What is the law between particle’s volume and energy?
I think: big volume – low energy, small volume – high energy.
The more speed / impulse ----> the more particle (as a volume)
compress ----> the more energy .
And when the speed decrease – - the energy decrease too –
but the volume of particle will increase.
My particle behaves like ‘a spring circle’ (!)
This spring circle can curl into small sphere which must
have volume and therefore can be describe as a
‘stringlike particle with vibrations’ only approximately .
You don’t believe me?
Well, then I ask you: before the particle started to curl
what form did it have?
Quantum of light has potential energy (- E=Mc^2 ).
When it starts to curl around its diameter the potential energy
(- E=Mc^2 ) is hidden and we can observe its electronic
energy ( E=h*f).
But there is situation when this hidden potential energy goes
out and we can see its great active power ( + E=Mc^2 )
looking the destroyed cities of Hiroshima and Nagasaki.
And maybe the particle’s transformation from one state into
the other was legalized as ‘ The Law of mass/energy
conservation and transformation’.
Different geometrical forms of string particle
( open - closed ), different frequencies of string particle are
reason of different radiation (from ultraviolet to infrared ),
are also reason of new situation in 2D.
Now the surface of my 2D in local area is changed.
On one hand it is electromagnetic field now,
on the other hand the spinning electron
changed the temperature of the surface in local area.
Now this local area has Debye temperature: Q(d)= h*f(max) / k.
Maybe in this space a grain of gravity theory is hidden.
It is no bad idea to ask question:
what are physical parameters of your new super D?
It is possible to understand many things using 2D.
The missing ‘big idea’ in ‘String theory’ is hidden in the
simple question: ‘ What was the form of particle before
it started to curl?’
I ‘mix bosons with fermions’ (page 105) without using
any supersymmetry. And I have:
a) In potential state the impulse of particle is h = 0. ( boson)
b) Having Planck’s inner impulse (unit h=1) my
particle moves straight with constant speed c=1. ( photon)
c) Having Goudsmit / Uhlenbeck inner angular impulse
h * = h /2pi. the particle rotates around its diameter.
( electron/ tachyon/ fermion).
Maybe the different conditions of (h) is the key to all
Maybe this process can explain ‘the dualism of particle.’
Maybe this interpretation can explain where the energy comes from.
Maybe . . . . .
Maybe it is time to end now.
I reread my article. It is not bad, not bad for amateur,
who thinks about philosophy of physics for 28 years.
Of course, my interpretation is only scheme. And if
I were a physicist I would make from this scheme a theory:
‘ Elementary particle as a spring circle’.
But as a peasant I can only hope that maybe somebody
from Smolin’s ‘few . . . most talented and accomplished
physicists’ will do it. Who knows? Why do I doubt?
Because I read Smolin’s opinion: ‘ Not that every scientist
is a seeker, most are not.’ (!) Ce la vie !
Now I must go to my farm, to my garden.
I want to plant some trees and flowers today.
All the best.
Israel Sadovnik Socratus