Thursday 30 April 2009

The Leap to a Quantum State


Hello Reader and welcome to the first segment of 3 all about Quantum Mechanics. Due to the science being so strange, I will cover as much as possible and to make sure you can grasp at least a little of what’s going on.

I will start off with this: We all have heard of Sir Isaac Newton and his Laws of Motion. You may not know the laws but you have heard his name associated with such phrases, I am sure. Newton was the one who came up with the concept of Gravity. And the ever so famous Action, reaction phrase... that was Newton’s Third Law!

Well it turns out; this is fine and dandy for macro scale. Objects that can be seen with the human eye, you, me, space shuttles, cannons, etcetera. But when we get to the micro scale, atoms, this is not right at all. Sub atomic particles move differently. This is where quantum mechanics starts playing a role in science.



In order to understand the next part, you must imagine what a wave looks like. That’s right, go back to High School Trigonometry and try to remember what a sine wave looks like. This is how light travels... in wave form.



Through experiments, it was determined that electrons when separate from the atom, also travelled in a wave. Now isn’t that strange? On a large scale, a bunch of atoms move using Newtonian Mechanics, but if you look at individual particles and sub-atomic particles, they act as waves. They even interfere like waves!


This is known as the particle wave duality. So one question that is out there is can light act like matter? We have not seen light (photon) act like a real particle with mass, but we have seen interactions between sub-atomic particles and a photon. This is what happens when humans perceive light and colour. A certain wavelength of an object is not absorbed and released. This wavelength is what we see. This is due to electrons gaining energy from a photon and then releasing it.

Electrons are weird little buggers. In an atom, the concept taught in High School is that they travel in circles around an atom. This is quite untrue. Instead, their positions are quite unclear. What is known, due to Schrödinger’s wave equations, is that there are probability “clouds” in which an electron could occupy in space and time. They do not stay in one place but “teleport” to another space in the probability cloud. This uncertainty gave rise to Heisenberg’s Principle of Uncertainty. He states that the position multiplied by the momentum of the object has to be larger than a constant. Thus, if one is item is very well know (say the momentum, which is mass x velocity), then the position of the electron cannot be well known.
A reason we cannot detect this is because the sophistication of our technology. A lot of out optical devises uses either photons or electrons to detect object positions. If a photon is what makes an electron excited and do not know the initial characteristics (velocity and position), the conditions cannot be deduced. Hitting an electron with an electron is also quite hard. But doing this does not help, seeming the wave feature of the electron allows it to be random in itself.

That is it for the basics of Quantum Mechanics. As always comments are encouraged.

Monday 20 April 2009

Coming Soon

Hello Reader,

I am excited for my next post(s). I have planned the next three around different aspects of Quantum Mechanics. I will be talking about Quantum Mechanics in general, then moving on to Quantum Computers and then finishing off wih Entanglement. I am currently doing the research for you because I don't know everything in this field. To be warned, Quantum Mechanics is very confusing and will be trying to simplify it for you, the Reader. As well, not everything is know about this subject matter, knowledge is very limited in the field so I am going to try to do this as thorough as possible.

The post won't be next week (probably) due to exam time. I will try to post the first one up before my flight to Fort MacMurray.

Good Day/Evening/Night to you.

As a side: Please comment on posts. I really want to know if there are readers out there. If no one posts comments, I may stop indefinatley. As always, suggeustions are welcome as well. I will cover many areas. I know recently I have done/will be doing physics, but I am will to do other topics as well.

Thank You Reader,
Keith

Thursday 16 April 2009

A flair for Flares

This post is going to take you, Reader, to an interesting side of physics! Astrophysics is quite a fun thing to think about, if you aren’t a rocket scientist. And to be clear, my specialty is NOT Astrophysics. I am going to discuss Solar Flares. Below is an image of the magnetic fields of both the Sun and the Earth.

In order to understand solar flares though, I will go over some things to make things a bit clearer.

The first thing to know about the Sun is that it is made up of Hydrogen atoms that fuse to make Helium atoms. This creates the heat that we feel on those warm sunny days (yes, summer is right around the corner, as they say). The energy of the hydrogen molecules are so significant that the 1 proton and electron from each atom will form into a new atom. This energy is called the Heat of Fusion. The temperature of the surface of the Sun is about 5725 C.

Our Sun has 3 layers to it, the core, the surface and the radiation zone. The radiation zone is very dense. Here the electromagnetic waves are produced and the radiation can stay in this zone for millions of years. Simply put, the energy can be in a wide range of wavelengths, from x-rays (large) or Gamma Rays (small).

So what is a solar flare? It’s an extra burst of energy that gets emitted from the Sun. This sends a “wave” of radiation (UV, x-ray and Gamma) outward. These are pretty dangerous wavelengths.

So why don’t we feel it? Actually, we kind of do. Cancer is a mutation in cells genetics. This can be due to many different agents. The most prominent reagent for skin cancer is UV radiation... from the Sun. The UV index actual flexuate, due to these solar flares and you get the advisory to put on sun screen.

Another aspect that is in movies including in the new cinematic entertainment, Knowing, is wireless interference. In movies, when a solar flare occurs, it creates interference waves for all technology that uses radio waves (electromagnetic waves). As established above, Radio waves ARE emitted from the Sun. It usually affects what is known as long range radio waves. These are the x-rays, and waves that have wavelengths in decimetres. We can thank the Ionosphere for this; it cuts “blocks” the larger wavelengths from getting through. Our cell phones have an average wavelength of approximately 26 centimetres or 2.6 decimetres. Thus, a solar flare is ABLE to interfere with our cell phone signal.

But these flares occur very often. During an “active” Sun phase, the Sun could produce a solar flare every few hours. When the Sun is inactive, solar flares can be produced once a week.

Flares occur when the outer “atmosphere” of the Sun has a burst of stored magnetic energy. It’s like a water balloon; the magnetic energy fills up in a concentrated area and then bursts releasing electromagnetic waves and lot of heat.