Presentation on detection of gravitational waves for students

1. Dr. Sunetra Dhere
Assistant Professor in Physics
S. H. Kelkar College, Devgad, Dist. Sindhudurg
sunetradhere@gmail.com

2. General Theory of Relativity
• Einstein published GTR in 1916
• Predicted existence of gravitational
waves
• First direct detection of gravitational
waves on September 14, 2015 @
LIGO & VIRGO
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3. Space-time fabric
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4. Gravitational Waves
• Generated by acceleration (or
deceleration) of massive objects in the
cosmos.
• Different nature than electromagnetic
waves.
• Follow the inverse square law.
• Travel with speed of light (3×108 m/s).
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5. Black hole
• End stage of a massive star
• Dense, compact, possesses extremely
high gravitational field
• Light cannot escape the gravity of
black hole
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8. Source of detected gravitational waves
• Black holes, 29 and 36 times our sun,
spinning around and merged.
• The 3 times mass of our sun was
converted into energy in 0.2 s.
• The energy was in the form of
gravitational waves.
• Black hole of mass of 62 times our sun
was formed.
• The event took place 1.3 billion years
ago!
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University, Goa

9. Source of detected gravitational waves
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10. Laser interferometer gravitational-wave
observatory (LIGO)
The most sensitive instrument ever built!
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11. LIGO works on principle of
interference
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12. Neutrino
astronomy
Higher education
Outreach
LIGO scientific
collaboration
IndiGO
LIGO-India
Gamma-ray
astronomy
Radio astronomy
X-ray/ UV astronomy
General relativity
Theoretical physics
Quantum gravity
Precision measurements
& fundamental tests
Quantum metrology
Laser physics
Vacuum technologies
Optical engineering
Sensor technologies
Control systems
Grid & cloud
computing
LIGO India: Avenues
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13. Reference
• Ripples from the past, R. RAMACHANDRAN, FRONTLINE (The Hindu),
March 02, 2016
• Images are from online resources and used for educational purpose only
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