Friday, March 21, 2014

Discoveries in Physics: Making a Big Bang in History

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To say that there have been significant discoveries in quantum physics recently is an understatement. The discoveries made in the past two years have been life changing, and it is an exciting time to be witness to human advancement. The discovery of gravitational waves this week was probably the biggest scientific discovery of our lifetime, and it follows the second biggest: the Higgs Boson.


Particle physics is essential to discovering the way that the universe formed and what makes everything around us what it is. Why is everyone so excited about these discoveries and how will it impact our lives?

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The Higgs Boson

Everything that we know is made up of subatomic particles. Things we see are made up of molecules, which are made of atoms, which are made of electrons, neutrons, and protons, which are made up of the particles, forces, and interactions described in the “Standard Model.” The Higgs Boson is what gives particles mass. It explains why we can touch everything around us without passing through it.


The Standard Model of Particle Physics was developed in the 1970s by a group of scientists around the world. The discovery of the Higgs Boson validated parts of the standard model. This discovery has guided physicists to new theories and disproved others. The video below describes the standard model and the experiment to find it beautifully.






Discovering the Higgs Boson required an experiment 40 years in the making. One of the most expensive and well thought out experimental setups in history, the Large Hadron Collider was used by a group of over 3,000 scientists to look for the Higgs Boson. It consists of a particle collider that spans a 17-mile loop underneath the Swiss-French border near Geneva.  Particle Fever is a film out in theaters now, and follows the scientists that worked on the Hadron Collider involved in in their discovery. I saw it last weekend and would highly recommend it to scientists and non-scientists alike. It explains the discovery and documents its importance flawlessly. I even got a little teary eyed when they announced the discovery, which is depicted in the photo below. 

Source:  Peter Higgs celebrating the announcement that they found the Higgs Boson at a CERN meeting

Gravitational Waves


Nearly 100 years ago, Albert Einstein came up with the theory of relativity. The theory states that the force we know as gravity is actually a warping of spacetime, a fusion of space and time. Imagine spacetime as a large sheet of gelatin-like material that jiggles when disturbed. He predicted that a violent event could trigger a waves or ripples in spacetime. This was a pretty out of this universe (pun intended) way to think 100 years ago. These waves are referred to as gravitational waves, and we have never been able to measure them before now.

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The Big Bang or Inflation Theory describes the “violent” event that causes these waves. It states that the universe expanded at a rate faster than the speed of light when it began. In order for anything to travel at a speed faster than light, infinite energy is required, or time travel. Something moving through spacetime is a possible way to travel at such speeds. According to inflation theory, the universe started from a single particle and expanded to its enormous size in  0.0000000000000000000000000000000000001 seconds. This Nature article explains gravitational waves in detail. 

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Until this week, gravitational waves had never been detected to prove this theory valid. Physicists successfully measured gravitational waves at the south pole using a telescope called Background Imaging of Cosmic Extragalactic Polarization 2 (BICEP2). When observing the microwave radiation left over from the Big Bang, they noticed that background radiation they were observing was polarized, meaning that it was traveling in waves that were all moving in a few specific directions, not random ones.

For more details on the experiment and inflation theory, this article in Time does a great job of breaking it down. One of the physicists that co-authored the discovery, Dr. Randol Aikin, did an AMA on Reddit and explains the process, what it means, and what is life is like. The full paper in available in Science is also available here

Source:  BICEP2 instrument at the South Pole Telescope facility    

How do these discoveries benefit non-physicists?

Both of these discoveries are results of basic science. My post on science research funding goes over the ways that basic science benefits our economy and why it is important to continue investing in it. Many people are probably asking why these breakthrough discoveries in quantum physics are so important to us and how they might benefit society.

The real answer is that nobody knows. The technological impacts that will be made as a result of these discoveries are far in the future and there is no way to know what they will be. To quote David Kaplan in the film Particle Fever when asked what the economic benefit is of finding the Higgs Boson: “It could mean nothing, other than just understanding everything.” The same is true for the discovery of gravitational waves, and whatever may precede that discovery (fingers crossed for dark matter).

The practical uses of this understanding can take decades to emerge, but they are typically life changing. Examples from other history changing discoveries are abundant. As a result of quantum mechanics, we have developed microchips, cellular phones, computers, lasers, and many other technologies. The discovery of radio waves revolutionized the way we communicate. Data produced from doing the experiment to find the Higgs Boson has already led to advances in computing, including the development of cloud computing.

This has been one of the most historic weeks in science to date, and in the last three years we have made leaps and bounds in our understanding of the universe. I am excited to find out what the next historic discovery will be. Here’s to being witnesses to these great times in physics exploration! 



Thanks for reading, and cheers to your brain!

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