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Showing posts with label physics. Show all posts
Showing posts with label physics. Show all posts

Wednesday, March 31, 2010

And it didn’t end the world by making a giant black hole!

In the 1970s, three physicists, Peter Higgs, Robert Brout and François Englert, sat down and tried to figure out how the universe began. It had just been discovered that magnetism, electricity, light and some radioactivity were all different expressions of the same force know as the electroweak force, but in order for this theory to work, the particles carrying the force must have no mass (they know this because they did fancy-pants math). Particle physics proves that these particles do have mass, so Brout, Higgs and Englert came up with the idea that maybe all particles had no mass right after the Big Bang. As the universe cooled, an invisible force (Higgs field) formed with these non-mass particles (Higgs boson). Any particle that came in contact with these forces gained a mass. The longer they interacted, the more massive they got. If they never interacted, they never got a mass. In theory this works great, but scientists have still never seen the Higgs boson (aka: the God Particle) – well, not yet…

I don’t know about you, but that hurts my head when I try to understand it. I’ll throw it out there again, I am not a physicist. That means I am really not a particle physicist. But in the wake of the huge news yesterday (and a request from a friend), I want to talk about the European Organization for Nuclear Research’s (CERN) Large Hadron Collider.


The Large Hadron Collider (LHC) is a $10 billion piece of equipment that is 17 miles around (spanning the border of France and Switzerland), roughly 300 feet underground and operating at -271.3°C (that is just a little bit above absolute zero – the temperature at which molecular movement is theorized to stop). This machine is the product of thousands of scientists, all hoping it will uncover the answers to some of physics craziest questions: what is the “God Particle”, why is there no more anti-matter, what is dark matter, are there other dimensions in the universe, and how did the Big Bang work?

This is all highly theoretical science and it is very easy to get lost in the jargon and complex physics. I want to just give you a basic idea of what is actually going on.

The LHC is a giant ring comprised of two tubes. Each tube contains a single beam of particles traveling (each tube in an opposite direction) nearly at the speed of light (0.999999991 times the speed of light) in a freezing cold, ultrahigh vacuum. The particles (Hadrons) used are protons and iron ions (charged iron) because of their size, charge and ability to prevent decay and loss of energy as they travel. The beams are guided along the track by powerful magnets: 1232 dipole magnets (15 meters long) bend the beams and 392 quadrupole magnets (5–7 meters long) to focus the beams. Each magnet is super cooled with liquid nitrogen and liquid helium.

The two tubes intersect at 4 places along the track, allowing for collisions. The energy released from a head on collision between two beams is equal to the sum of both beams. Basically, when these two beams smash into one another at such high speeds, they release so much energy that temperatures can reach more than 100,000 times hotter than the sun!

There are 6 experiments (6 socialized machines) constantly recording data from each collision. These are intense machines. Some are over 7 stories tall and can still record time to the billionth of a second and distance to the millionths of a meter. With over 600 million proton collisions a second, about 15 petabytes (15 million gigabytes) of data gets generated a day! Obviously they have some impressive computer systems to back all of this equipment up with.

Yesterday the science world was amazed when, for the first time, beams of protons were hurled around the LHC, smashed into one another and released an energy of 3.5 trillion electron volts (7 times higher than ever created before)! Trust me, that’s AMAZING!

All that sounds great and is super exciting, but what does this mean for the everyday person? Nothing really. But this is still some awesome stuff to learn!

Tuesday, February 23, 2010

I don't care what people say, I still love the sport!

In honor of the Olympics I am going to talk about one of the major natural phenomena that almost all of the winter athletes have to take into account: friction.

Friction is a force resisting motion of solids, liquid layers and elements in contact. Basically, friction is the force opposite of motion. When you think of friction, you are probably thinking about kinetic friction. This is the friction created by two objects when moving relative to each other. A specific type of kinetic friction is fluid friction. This is when a solid object moves over/through a liquid of gas. Friction is created because of charge particles.

Flashback: Every object is comprised of little tiny itsy bitsy molecules that have charges.
Molecules have a nucleus with a positive charge (protons are positive and neutrons are charge neutral) and the nucleus is surrounded by negatively charged electrons. Most molecules end up have an overall net charge of zero, but charges can change.

When two objects move past one another, their charged particles are passing one another. You should know that two opposite charges do not like one another. When charged particles are forced past other charged particles, resistance (friction) and heat (thermal energy) is created. Need a visual? Rub your hands together. They don’t just slid past one another easily (friction) and they will start to warm up (thermal energy).

That was a nice little intro into friction, but trust me, after taking physics you will learn there is a LOT more to friction (actually, I feel like I say that in almost every post – I guess just know I am giving you very basic foundations of scientific knowledge in these posts). Now I want to apply it to one of my favorite winter sports: curling.

In curling, a person pushes their stone down the ice in hopes of knocking the opponents stones out of the way and landing closest to the center of the target - very simple concept, but lots of physics to think about.

After the stone is released, friction between the stone and the ice will cause the stone to gradually slow until it stops. To reduce this friction, the ice of curling matches is not smooth. It is sprayed with water to create a surface with lots of tiny ice bumps. This reduces the amount of ice surface area the curling stone will come in contact with and thereby reduces the amount of friction the stone will encounter. Sweeping the path in front of the stone creates friction and the thermal energy (heat) actually smoothes and softens the ice a little (about 1.5 degrees) to help guide the curling stone. Until very recently people thought the ice being swept in front of the stone actually melted – thermal imaging cameras destroyed that theory a few months ago. The sweeping actually only softens the ice.


Researchers were hired by the Canadian government to study the physics of curling (they released the data above) and I would love to tell you more of the results they found, but the Canadian government has them under confidentiality contracts until June 2010. Canada really wants gold this year!

Here is a link to a video with footage of the thermal imaging cameras: http://www.cbc.ca/technology/story/2010/02/05/f-tech-physics-curling.html?ref=rss