STRING THEORY

1
String Theory

• By Cadet W

2
What is it?

• String theory is a theory combining the theory of
  relativity, created by Albert Einstein and the
  theory of quantum mechanics, created by Gustav
  Kirchhoff, Josef Stefan and many others. There is
  a lot of controversy going on about the theory
  among the worlds greatest scientists.

3
QUANTUM OR RELATIVITY?

• Quantum mechanics (top) is the study of small
  things, electrons, quarks, gluons and things of
  that nature.
• General relativity is the study of planets and
  galaxies, it states space is a kind of fabric
  everything floats on.
• Special relativity is the study of the speed of
  light and other forces, it explains the Lorenz
  contraction and time dilation.

4
LORENTZ CONTRACTION AND TIME DILATION

• The Lorentz contraction is the contracting or
  shortening of an object as its velocity
  increases. This can be proven mathematically and
  is an actual law of physics.
• Time dilation is time slowing down for an object
  as it approaches the speed of light this has also
  been proven and is a law of physics.

5
WHATS THE PROBLEM?

• The problem is when you add them together you get
  gibberish, thats were string theory comes in, it
  combines both theories to make a sort of super
  theory that makes sense mathematically. Thats
  were strings came in.

6
NO, REALLY WHAT IS IT?

• String theory states that all things are made out
  of miniscule strings either open or closed that
  vibrate different ways to create different
  sub-atomic particles and even gravitons, the
  particles that are supposed to make gravity. The
  strings are also supposed to make up the fabric
  of space.

These are all subatomic particles all are proven
to exist except the graviton
7
DIMENSIONS

• The curious feature of superstrings, is that they
  can only vibrate in 10 dimensions. This is, in
  fact, one of the reasons why it can unify the
  known forces of the universe in 10 dimensions
  there is "more room" to accommodate both
  Einstein's theory of gravity as well as
  sub-atomic physics. In some sense, previous
  attempts at unifying the forces of nature failed
  because a standard four dimensional theory is
  "too small" to jam all the forces into one
  mathematical framework. The four dimensional
  theory being x,y and z axis and the dimension of
  time.

8
EXAMPLE

• To visualize higher dimensions, consider a
  Japanese tea garden, where carp spend their
  entire lives swimming on the bottom of a shallow
  pond. The carp are only vaguely aware of a world
  beyond the surface. To a carp "scientist," the
  universe only consists of two dimensions, length
  and width. There is no such thing as "height." In
  fact, they are incapable of imagining a third
  dimension beyond the pond. The word "up" has no
  meaning for them. (Imagine their distress if we
  were to suddenly lift them out of their two
  dimensional universe into "hyperspace," i.e. Our
  world!)

9
ANOTHER EXAMPLE

• If it rains, the surface of their pond
  becomes rippled. Although the third dimension is
  beyond their comprehension, they can clearly see
  the waves traveling on the pond's surface.
  Likewise, although we earthlings cannot "see"
  these higher dimensions, we can see their ripples
  when they vibrate. According to this theory,
  "light" is nothing but vibrations rippling along
  the 5th dimension. By adding higher dimensions,
  we can easily accommodate more and more forces,
  including the nuclear forces. In a nutshell the
  more dimensions we have, the more forces we can
  accommodate.

10
CRITICISM

• One persistent criticism of this theory is that
  we do not see these higher dimensions in the
  laboratory. At present, every event in the
  universe, from the tiniest sub-atomic decay to
  exploding galaxies, can be described by 4 numbers
  (length, width, depth, and time), not 10 numbers.
  To answer this criticism, many physicists believe
  (but cannot yet prove) that the universe at the
  instant of the big bang was in fact fully 10
  dimensional. Only after the instant of creation
  did 6 of the 10 dimensions "curled up" into a
  ball too tiny to observe.

11
FURTHER STUDIES

• Currently Stephen Hawking and other theoretical
  physicists are working on making the theory
  easier to understand mathematically and
  logically, also attempting to prove that this is
  the theory maybe by creating a microscope
  powerful enough to see the strings.

12
THE END