April Post: Scientists of LIGO AMA

This month was full of preparation for my presentation as well as organization. While searching for another source for research check, I found a reddit AMA (Ask Me Anything) that scientists that worked at LIGO created. It was full of very helpful and insightful information. I learned so much from it, and the best part is that they are able to explain what they do in layman terms. It's very understandable.

There are also several intelligent questions that I might have asked if I was there. Very insightful!

Here is the link to the AMA.
http://www.reddit.com/r/science/comments/2vrcdm/science_ama_series_were_scientists_of_the_ligo/

Blog 19: Independent Component 2

LITERAL

(a) Include this statement: “I, Denesh Chandrahasan, affirm that I completed my independent component which represents 30 hours 40 minutes of work.”

(b) Cite your source regarding who or what article or book helped you complete the independent component.

- My most important sources in helping me do this component were:

1. Faesi, Chris. "The Race to Detect Gravitational Waves: Pulsar Timing Arrays." Astrobites. Astrobites, 23 Nov. 2012. Web. 17 Apr. 2015.
2. Feynman, Richard P. QED: The Strange Theory of Light and Matter. Princeton, NJ: Princeton UP, 1985. Print.
3. Vivian, Geoff. "'Listening' to Black Holes Form with Gravity Waves." 'Listening' to Black Holes Form with Gravity Waves. Phys.org, 16 Aug. 2013. Web. 03 Apr. 2015.

The 1st source was very helpful since it introduced the concept of pulsar timing arrays, which led me to studying gravity waves' interference. The 2nd helped me by giving me a strong foundation in how exactly light works in relation to reflection and wavelengths. The last source was the most helpful because it taught me about interference patterns and how black holes can form them.

(c) Update your Independent Component 2 Log (which should be under your Senior Project Hours link)

- Done.

(d) Explain what you completed.    

- Essentially I used my homemade interferometer that I had created and assembled from Independent Component 1 to see if gravity waves have interference (which is explained later). Because producing gravitational waves are extremely hard to detect and would require expensive equipment, I used light as a model for gravitational waves. I created a "double-slit" experiment that demonstrated that gravity waves could have constructive interference. (Read my Senior Project hours Log for the details).

INTERPRETIVE 

Defend your work and explain its significance to your project and how it demonstrates 30 hours of work.   Provide evidence (photos, transcript, art work, videos, etc) of the 30 hours of work.  

- The interferometer is extremely significant to my project since it is literally my first answer to my EQ (What is the best solution for detecting gravitational waves?). I put this interferometer into use by trying to demonstrate that gravitational waves could theoretically have interference patterns. Basically, wave interference is the phenomenon that occurs when two waves meet while traveling along the same medium. This is important to my EQ because in order to detect gravitational waves properly, all my answers (interferometers, pulsar timing arrays, and Weber bars) would have to take this into account.

This demonstrates 30 hours of work since I researched the procedure, brought together some parts, studied videos and models online, actually physically built the setup, used my interferometer, then tested it. 

Pictures

Waves from my bathtub are best example of interference that I found before this experiment. Notice how the waves form a pattern when they hit each other. This is how I predict gravitational waves would occur too.

This is the completed interferometer that I created from independent component 1, luckily nothing broke yet.

The basic materials from home used to create the slit.

Marking the areas that I was going to cut.

Cut small slits in the card stock.

Covered the slits with aluminum.

I used the laser pointer from my interferometer by detaching it from the apparatus. I then shone the laser into the double slits to see if there was any pattern..

What we see is nothing like passing particles through two slits! We see a clear interference pattern! Also, what we are seeing are the multiple "ripples" of the light wave with clear interference patterns where the "ripples" intersect.

APPLIED

How did the component help you understand the foundation of your topic better?  Please include specific examples to illustrate this. 

-  This independent component helped me understand the mysterious gravitational waves because it illustrated how they would interact with one another when they hit. Since gravitational waves are produced by massive bodies such as black holes, it should be natural for them to collide since they are from different sources. My experiment made me use light (since light is also a type of wave) to replicate gravitational waves. The fact that gravitational waves could interference with one another is crucial to existing detectors.

All my answers are various forms of detection, and they would certainly need to know that gravitational waves collide with one another. This information would allow the detectors to be more precise. The real-life examples that are applicable is LIGO. Currently, the most sensitive interferometer is LIGO – the Laser Interferometer Gravitational Wave Observatory. 

Each consists of two light storage arms which are 2 to 4 kilometers in length. These are at 90 degree angles to each other, with the light passing through 1m diameter vacuum tubes running the entire 4 kilometers. A passing gravitational wave will slightly stretch one arm as it shortens the other. This is precisely the motion to which an interferometer is most sensitive.

This component also would support our current model of Physics by proving that gravitational waves can also follow the same behavior as waves (aka light, sound). This is something suggested by Einstein's theory of relativity, but has yet to be proven. Interferometers like I built are simple models of the big ones that can someday detect those waves when 2 black holes collide.

March Post: LIGO Again

This month was very great for me as I heard from many great colleges, and that I got into my dream school - Berkeley! I spent considerable time looking at the physics facilities that they offered.

One of the most famous facilities that I mentioned throughout my lessons as well as planned for my final presentation, is LIGO. I researched the following information of this detector.

One of the most sensitive detectors in human history is NSF's Laser Interferometer Gravitational-wave Observatory (LIGO). Located in two separate facilities nearly a continent apart, the LIGO interferometers can detect vibrations far smaller than an attometer (1,000,000,000,000,000,000th of a meter). More than 900 scientists, engineers and others support the effort — some having been involved for more than twenty years — all contributing to a single goal: detection of gravitational waves, ripples in space-time predicted by Albert Einstein that have yet to be directly detected.

A very helpful video that explains this visually is below.

http://www.space.com/28496-gravitational-wave-detector-ama.html

Blog 18: Fourth Interview Questions

Content: Post 20 open-ended questions you want to ask an expert in the field concerning your senior project. The focus of your questions should be on your answer to your EQ.

1. What are the possible outcomes and benefits of the discovery of gravitational waves?
2. Why is studying the universe and black holes so important when we have a lot of problems here on Earth?
3. Using our current forms of detection, when do you predict the first real evidence of gravitational waves? Why?
4. What would it mean if gravitational waves simply do not exist? 
5. What are the implications if we could never detect gravitational waves in the future?
6. What would be the ideal interferometer to detect gravitational waves? 
7. Do you believe that LIGO could ever detect the waves? 
8. What is the most important data that an interferometer could find to prove that the waves exist?
9. What are the benefits that interferometers have that other forms of detection don't?
10. What exactly is a Pulsar Timing Array in your own words, and how does it essentially work?
11. What would happen to Pulsar Timing Arrays if in fact the gravitational waves do not affect the pulsar pulses?
12. How can we detect the perturbations from the pulsar?
13. Why are Weber Bars so unpopular currently by detection scientists?
14. Could Weber Bars ever work in situations that interferometry could not?
15. Why are some Weber Bars still used?
16. What are your predictions of the use/interaction of gravitational waves?
17. Could we be able to, in a way, "control" gravity particles if this discover is found?
18. Are we getting nearer to detection than before? Or have we barely made progress?
19. What do you think of the supposed detection by BICEP2 last year?
20. What is the best advice you can give me since I am interested in potentially pursuing this career in trying to find gravitational waves?

Blog 17: Third Answer

1.) EQ 

- What is the best solution for detecting gravitational waves?

2.) Answer #3 (Write in a complete sentence like a thesis statement)*

- Weber Bars could detect gravitational waves with their use of heavy aluminum cylinders to see any change in frequency, disregarding "background noise".

3.) 3 details to support the answer (a detail is a fact and an example)

• These massive aluminium cylinders vibrated at a resonance frequency of 1660 hertz and were designed to be set in motion by gravitational waves predicted by Weber. 
• Because these waves were supposed to be so weak, the cylinders had to be massive and the sensors had to be very sensitive.
• These sensors are capable of detecting a change in the cylinders' lengths by about 10⁻¹⁶ meters.

4.) The research source (s) to support your details and answer

- Lindley, David. "A Fleeting Detection of Gravitational Waves." Physics -. American Physical Society, 22 Dec. 2005. Web. 05 Mar. 2015. <http://physics.aps.org/story/v16/st19>

5.) Concluding Sentence

- My 3rd answer differs from my first two since Weber Bars are much more restrictive and crude compared to the others, but can still work given the right conditions.

February Post: Gravitational Waves Might Not Exist?

This month, I found a very interesting article that argued that gravitational waves might not exist after all. If this is true, then my senior project would be greatly affected. Fortunately, this is not concrete evidence to prove that gravitational waves don't exist. However, it did still give me a new and fresh perspective on my esoteric topic. The link is below:

http://phys.org/news/2015-01-planck-gravitational-elusive.html

Essentially the article states:

Despite earlier reports of a possible detection, a joint analysis of data from ESA's Planck satellite and the ground-based BICEP2 and Keck Array experiments has found no conclusive evidence of primordial gravitational waves. "While we haven't found strong evidence of a signal from primordial gravitational waves in the best observations of CMB polarisation that are currently available, this by no means rules out inflation," says Reno Mandolesi, principal investigator of the LFI instrument on Planck at University of Ferrara, Italy.

Blog 16: Answer 2

1.)  What is your EQ?

- My EQ is "What is the best solution for detecting gravitational waves?"
2.)  What is your first answer? (In complete thesis statement format)

- Interferometers could detect gravitational waves with the usage of laser to see changes in space-time.
3.)  What is your second answer? (In complete thesis statement format)

- Pulsar Timing Arrays could detect gravitational waves with their perturbation-seeking-sensors through pulsars.
4.)  List three reasons your answer is true with a real-world application for each.

• The signal from a pulsar can be detected by radio telescopes as a series of regularly spaced pulses, essentially like the ticks of a clock.
• Gravitational waves affect the time it takes the pulses to travel from the pulsar to a telescope on Earth.
• A pulsar timing array uses millisecond pulsars to seek out perturbations due to gravitational waves in measurements of pulse arrival times at a telescope, in other words, to look for deviations in the clock ticks.

5.)  What printed source best supports your answer?

- Feynman, Richard P. QED: The Strange Theory of Light and Matter. Princeton, NJ: Princeton UP, 1985. Print.

6.)  What other source supports your answer?

- Moskowitz, Clara. "Dark Matter Black Holes Could Be Destroying Stars at the Milky Way's Center." Scientific American Global RSS. Scientific American, 10 Nov. 2014. Web. 12 Dec. 2014.
7.)  Tie this together with a concluding thought.

- My new answer differs from the 1st because pulsar timing arrays would scan the universe's space-time instead of looking directly at the waves, like a inteferometer does.