SCIENCE SUMMER PROGRAM INITIATIVE

By Ayush Sharma, in collaboration with Avanti

IMPORTANT

• Email • Clarifications from the last session

IS SPACE CONTRACTION REAL?

• The author unjustifiably stated a difference of Lorentz's view and that of mine concerning the physical facts. The question as to whether length contraction really exists or not is misleading. It doesn't "really" exist, in so far as it doesn't exist for a comoving observer; though it "really" exists, i.e. in such a way that it could be demonstrated in principle by physical means by a non-comoving observer.[18]

• — Albert Einstein, 1911

THEORY OF GENERAL RELATIVITY

HOW EINSTEIN’S BIGGEST ACHIEVEMENT SHAPED THE FABRIC OF SPACE-TIME By Ayush Sharma, in

collaboration with Avanti

NEWTON: THE MAN WHO ESTABLISHED PHYSICS• Sir Isaac Newton– One of the Greatest Intellects ever

born on Earth • Revolutionized the foundations of Physics and

Mathematics• Deduced his formula for Gravitation

NEWTON’S VIEW OF GRAVITY

• Gravitational Force: Dominant. Universal. Large scale Force of the Universe• Shapes structures ranging from planets to super-massive Galaxy

Clusters• Newton didn’t present any understanding of the force itself, but only a

formula!

A WAR BETWEEN GREAT MINDS– EINSTEIN VS NEWTON

• Newtonian Gravity conflicts with Einstein’s Special Relativity • Relativity prohibits anything from going faster than light• Newtonian Gravity has instantaneous gravitational effects

• Lack of Mechanism for Gravity • How does Gravitational force really work?

LENGTH CONTRACTION

• Special Relativity implies that both Space and Time can adjust.• Adjusting of Space implies that distances become smaller

when in motion• To see how and why this happens, consider a moving car, and

try to measure its length.

CONCEPT TEST

• If a person is running really fast along a road, when observed by someone standing, this man would appear—

A. TallerB. ShorterC. ThickerD. Thinner

MEASUREMENTS ON A SPINNING RIDE

• Consider a spinning ride• Consider what happens when taking measurement on this ride? • Leads to Contradiction of Euclidean Geometry!

HOW COULD THIS HAPPEN?How could this violation of such a basic principle happen?

THE ANSWER? – NON-EUCLIDEAN GEOMETRY

CONCEPT TEST

In which of the three kind of geometries, does the circumference of a circle exceeds 2(pi)r?

A. Spherical Geometry (Figure 1)B. Saddle-like Geometry (Figure 2)C. Flat Space Geometry (Figure 3)

VIDEO VISUALIZATION FOR SPACE-TIME

CONCEPT TEST

• An Astronaut in a space-craft is about to take-off from the ground, and he’s standing on a weighing scale. When the craft takes off, the reading on the scale–

A. IncreasesB. DecreasesC. Remains the sameD. Starts to fluctuate (random increase and decrease)

ACTIVITY: CAN YOU SAVE THE EARTH FROM THIS BOMB?

• How to save the Earth from a Gravity Sensitive Bomb? • The bomb goes off if the scale deflects by more than 10% of its

reading• Taking off to Space doesn’t seem like a solution.• What do we Do?

ANSWEROpposing effects from the acceleration of the space-craft and the decrease in Gravity can counteract each other keeping the reading of the scale at the same as that on the ground.

EINSTEIN’S HAPPIEST THOUGHT

• Gravitational force == Acceleration• Why did this make Einstein Happy? • What happened next?

THE FABRIC OF THE COSMOS

• Following Einstein’s insight leads us to a radically different and more elegant picture of Space-Time• Space-Time isn’t just a static arena anymore, instead it’s a

dynamic component of everyday reality, shaped by matter and energy.

RESOLVING THE CONFLICT

• Does General relativity allow for any resolution of the paradox we began with?

SEARCHING FOR RIPPLES IN SPACE-TIME

• Numerous experiments have verified the predictions of GR• Gravitational waves, one of the strange predictions of GR,

remained elusive to experiments until recently. • LIGO: MIT and Caltech joint effort in search of Gravitational

waves

TED TALK BY ALAN ADAMS

QUESTIONS AND DISCUSSION