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Scope Series 4 RTÉ Two, Thursday, 7.00pm

What is Gravity?

GravityThis week SCOPE is trying to defy gravity by keeping water in an upside down bucket!

The experiment can be simply done by swinging a bucket of water in a circle.

The action of swinging the bucket applies a fictitious centrifugal force to the bucket which is greater than the pull of gravity and hence the water stays in.

SCOPE has decided to push this experiment further and see if the same thing happens if the bucket of water is held by a person on the wing of a plane doing a loop-the-loop!

Gravity is the force that dominates our universe - without it we would not exist. In some parts of the universe there is a battle against the force of gravity.

Gravity is also quite beneficial to us on Earth but if you happened to find yourself living in the vicinity of a dying star or on the edge of a black hole you might not be so happy with your lot.

Gravity is the fundamental force that shapes things in the universe. The German-born Physicist, Dr Albert Einstein, developed a theory of gravitation which concluded that gravitation is a natural phenomenon by which all objects attract each other. One hot research topic for scientists working in the field at the moment is gravitational waves. A gravitational wave is a fluctuation in the curvature of spacetime which propagates as a wave, travelling outward from a moving object or system of objects.

Gravitational radiation is the energy transported by these waves. Millions of dollars are being spent to work out if these theorised waves, as predicted by Einstein, actually exist.  

Dr Paul Callanan, a lecturer in physics and astronomy at University College Cork, is involved in international studies to weigh black holes. Paul's specific area of research is looking for black holes. 

A black hole is a place in the universe where gravity has won and can be described as a region of spacetime from which nothing can escape, not even light! Being millions of miles away makes them very difficult to look at so Paul uses infra-red light in his search. He also examines how black holes affect their neighbours. 

Paul has predicted that the water should stay in the bucket on the plane but factors like wind and petrified presenters might result in a soaking!

For more on Paul’s research check out:

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