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Module: Relativitaet auf dem Pruefstand

Sequence: Start

Slide:

Branching Point: Putting relativity to the test - Was Einstein right ?

Sequence: (1) Time Dilation

Slide: Moving keeps you young

Slide: Time dilation at different speeds

Slide: Test of Time Dilation

Slide: "Race-track" for Ions

Slide: Atoms are very precise clocks

Slide: Laser spectroscopy with fast Ions

Slide: Doppler Effect

Slide: Time dilation confirmed anew

Sequence: (2) equivalence principle

Slide: All Objects Fall the Same Way

Slide: In the Vacuum All Objects Fall With the Same Speed

Slide: Elevator Thought Experiment

Slide: Tests: From Galilei to Newton

Slide: Test Masses of STEP

Slide: STEP: A modern experiment of free fall

Slide: Satellite Test of the Equivalence Principle

Sequence: (3) Shapiro

Slide: Echos from satellites are very late

Slide: The Experiment

Slide: The Cassini Satellite

Sequence: (4) GP-B

Slide: Tops are tilting in the gravitational field of the Earth

Slide:

Slide: Perfect Spheres

Slide: The Gravity Probe B Satellite

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Forward

Atoms are very precise clocks

Atoms absorb and emit light with characteristic frequencies. This is why todays time standards are based on atomic clocks.

If the atoms move with respect to an external observer, a lower frequency is measured. How large the frequency is - that is how fast for emitted light one wave follows another - is a direct measure for the elapsing time in the reference frame of the atom.

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