Quantum Mechanics

Five Main Ideas of Quantum Mechanics:

1. Energy is not continuous, but comes in small but discrete units.

2. The elementary particles behave both like particles and like waves.

3. The movement of these particles is inherently random.

4. It is physically impossible to know both the position and the momentum of a particle at the same time. The more precisely one is known, the less precise the measurement of the other is.

5. The atomic world is nothing like the world we live in.

1. Energy is not continuous, but comes in small but discrete units.

E=hv h = Planck’s ConstantPlanck's length: Quantum of

length (about 10-35 meter)Planck's time: Quantum of time (about 10-43 sec),

Max Planck

2. Particle Wave Duality

At the quantum level all particles behave like both particles and waves.

4. Heisenberg Uncertainty Principle: The position and velocity of a particle cannot be known simultaneously.

Double slit experimentWerner Heisenberg

The movement of these particles is inherently

random.

Making an observation collapses the wave function of the particle from all possibilities to the one observed.

Schrödinger’s Cat

Erwin Schrödinger

Many Worlds

Every time an observation is made that collapses the wave function, all possible outcomes happen in parallel universes.

Schrödinger’s Cat is both dead and alive.

HUGH EVERETT, III

The Problem:Quantum Mechanics and Relativity do not

agree.Quantum explains E/M, Strong and Weak

Nuclear forcesRelativity Explains Gravity

String Theory (“M” Theory)

Search for a theory that works everywhere and explains everything.

Everything in the universe (or all of the universes) are simply made of tiny vibrating strands (strings) of energy.

These strings vibrate in 10 or possibly 11 dimensions.

Edward Witten

Calabi–Yau manifold

Calabi–Yau manifolds are important in superstring theory. In the most conventional superstring models, ten conjectural dimensions in string theory are supposed to come as four of which we are aware, and these manifolds carrying six additional dimensional fibers.