Think of the smallest particles we know about, such as atoms, protons, neutrons, and electrons. These are the building blocks of all living things and are the smallest parts of matter and energy. When studying them, mathematics is the key to really understanding how these small parts of the world work together on a larger scale.

Quantum Physics has been defined by its history and the various theories this molecular study has spawn.

Other theories, such as the photoelectric effect, was the beginning of a run of experiments and hypothesis that challenged the classic wave theory. Over time, these hypotheses and experiments have built the foundation of data that is the basis for quantum physics or quantum mechanics.

The experiments discussed include the Double Slit Experiment and how it effects the Classic Wave Theory. At the same time, these experiments gave scientists the chance to observe effects that would contribute to the theories that are now part of quantum physics. Other theories highlighted within these pages include the Photoelectric Effect, the Compton Effect, and even the uncertainty principle.

The problematic issue with a fully unified field theory is Einstein’s theory of general relativity best explains gravity. But the other three fundamental interactions and their quantum mechanical nature are best explained with the Standard Model. The curvature of space-time, which is fundamental when discussing relativity, leads to snags in the Standard Model’s quantum physics depictions.

A few theories that attempt to unify the model with Relativity include: Quantum Gravity – Generally is posed that a theoretical entity or a graviton, which is a virtual particle to represent the force of gravity. This is what differentiates quantum gravity from other theories within the world of unified theory. Some theories are classified as quantum gravity , but lack a graviton. String Theory – Imagine building a model using nothing but one-dimensional filaments and eliminating more traditional particles. These filaments vibrate at specific frequencies. The formulas resulting from this theory calculate more than 4 dimensions, but the dimensions are bent according to the Planck length. Loop Quantum Gravity – This theory seeks to express the modern theory of gravity in a quantized format. The method comprises viewing space and time as broken into discrete chunks. It is viewed by many as the well-developed alternative theory to the top two in this list. Theory of Everything – This theory is a theoretical all-encompassing framework of physics explaining and linking together all physical aspects of the universe. Supersymmetry – A theory of particle physics, is a type of space-time symmetry connecting two basic elementary particles classes. The first are bosons, which have an integer-valued spin. The other is fermions, which have a half-integer spin. A particle from each group associates with each other, creating a superpartner, with a spin differing by a half-integer. Perfectly unbroken supersymmetry, in theory, means that each pair of superpartners shares the same mass and internal quantum numbers, in addition to their spin.

As these theories show, the idea of one unifying theory has been difficult to prove and hard to identify. Unified field theory is highly academic, and to date, there is not any concrete evidence that unifying gravity with all the other forces is even possible. Historically, other forces have been combined, and many physicists are willing to devote their lives, careers, and reputations attempting to show that gravity can also be expressed quantum mechanically. The magnitudes of such a discovery, of course, cannot be fully identified until experimental evidence proves a viable theory.

The Earth and the Universe, in particular matter and energy that are their building blocks, are governed according to the various laws of physics. No matter where we go or what we do, these physical laws are always in force and remain absolute. These physical processes govern how matter and energy can be transformed and its behavior in various situations where they interact with other elements or forces. Beyond the physical aspects of the world, we can see, there is another microscopic world operating under its own set of laws, also governing the behavior of matter and energy. Scientists describe this set of laws in a group of theories known as Quantum Physics, or the study of how matter and energy behave on the atomic, nuclear and even smaller microscopic levels.

So what makes Quantum Physics so special within the broader scope of Physics itself? To answer that, it’s important to remember that Quantum Physics uses math to explain how energy and matter behave. In other sciences, the observation of an experiment or a phenomenon does not influence the processes taking place. With Quantum Physics, observation does influence the processes, because the equations are developed to explain what was observed. As the next few theories display, it’s the scientists’ observations that guide the overall development and the adjustments of the mathematical equations that are the brains of Quantum Physics.

Closing the gap between several quantum physics theories is the superstrings theory or the theory of everything because this theory ties so many different aspects of Quantum Physics together. But how did it come about? First, let’s explore some of the theories and how their gaps allowed for the superstrings theory to be born.

It all starts with light. Electromagnetic fields are defined by mathematics. Then with the discovery of electrons, particle physics was born. As a result of quantum mechanics, both the equations and the observations, particles were divided into two classes, bosons, and fermions. Only one fermion can occupy a certain state at a certain time, thus making them the particles of matter. Thus solids cannot pass through each other. The Pauli Repulsion explains this inability of matter to share the same space as forces can.

Throughout the development of quantum mechanics, evidence grew up that indicated light always traveled at one fixed speed, no matter the direction. Einstein developed a Special Theory of Relativity to describe this discovery. This theory, along with other developments of quantum physics, resulted in the rich subject known as relativistic quantum field theory. This is the foundation of what physicists use to define the actions of subatomic particles.







Einstein was a busy scientist though. His special theory encompassed Newton’s theory of gravitation. When he did that, he defined the General Theory of Relativity and the mathematics of differential geometry into the world of physics.

Relativistic quantum field theory works when we neglect gravity because it is so weak. Particle theory also seems to work best when scientists pretend that gravity doesn’t exist. General relativity has given scientists greater insight into orbits of planets, creation, and lives of stars, even black holes. But this theory works only when scientists essentially pretend the Universe is classical and describing nature doesn’t require quantum physics.

String theory began as an explanation for the relationship between spin and mass for hadron particles, which include a proton and a neutron. While another better explanation was found, string theory found a home in helping to bring the particle and gravity communities together.

Particles in this theory are rising due to excitations of a string, but included in these particles are one with zero mass and two units of spin. If a quantum theory of gravity existed, then the particle carrying gravitational force would include the zero mass and two units of spin. This particle has been called a graviton. Early string theorists proposed that their theory shouldn’t be applied to hadronic particles, but to quantum gravity.

In string theory, the strings are colliding in a small and finite distance. The zero distance behavior means that scientists can now combine gravity and quantum mechanics. This theory allows scientists to talk about string excitation carrying gravitational force. Within this theory, there were questions that the researchers and scientists could not answer. Our discussion will cover several types of string theories and how they have recently been combined under the M-theory.

This would seem to be a most remarkable aspect of nature, and a discovery resulting from the application of quantum theory. Bell’s work, which should apply to any fundamental theory of nature (i.e., not just quantum theory), could turn out to be one of the most important theoretical ideas of this century.

In spite of much enthusiasm in the last decade, there now appear to be certain loopholes in experiments like Aspect’s, based on the statistical analysis of hundreds of measurements. These loopholes have reverted the proof of Bell’s theorem to that of an open question. Einstein and the EPR paradox still lives! Much research is going on worldwide on this question, as noted from the web page recently downloaded from the Internet.

Quantum Theory and the New Millennium

The famous exchange depicted in the photo on this page does not represent Einstein’s most serious challenge to Bohr’s interpretation of quantum theory. Schrödinger’s waves and Heisenberg’s uncertainty principle do work! But the EPR paradox is another matter.

The string theory not only helped overcome some hurdles within physics, but it also inspired young people to learn this complex math to study the quantum theory of interacting strings. So how can we describe these strings?

It’s all in a guitar string. One that was tuned through stretching the string and providing tension. When it’s plucked, it produces a variety of musical notes or excitation modes. Put elementary particles in the place of musical notes, and we have the excitation nodes of elementary strings. The string must be stretched with tension to get them into an excited state. But these strings aren’t tied to a guitar but float in space. Still, they have tension. But for a theory to work with quantum gravity, the average string should be near the length scale, otherwise called the Planck Length.