Einstein

time dilation examples

1) Photon clock: Bouncing of a photon takes longer to get to a moving set of parallel mirrors compared to the starting point. 2) GPS satellites and ISS have a 0.007s time difference over 6 months compared to objects on the Earth.

Properties of Special Relativity

1) time dilation 2) energy to mass equivalency 3) length contraction 4) relativity of simultaneity 5) finite speed in the universe

Albert Einstein (1879-1955)

1. German physicist whose theory of special relativity undermined Newtonian physics. 2. Challenged traditional concepts of time, space, and motion. 3. Contributed to the view that humans live in a universe with uncertainties. 4. Added to the feeling of uncertainty in the postwar world.

mass-energy equivalence

E=mc^2 Energy can be converted to mass or mass can be converted to energy.

general relativity

Gravitational attraction between masses is a result of the nearby masses bending spacetime.

Special Relativity: Spaceship Example

If I have headlights on my spaceship, the light will NOT go the speed of light 300,000,000 m/s + 7700 m/s (the speed of my spaceship).

Einstein's cross

Mirage of stellar objects caused by gravitational lensing.

spacetime

The inseparable, four-dimensional combination of space and time. Can be thought as the fabric of the universe, which is bent and folded by massive objects producing gravity waves.

gravitational lensing

The magnification or distortion (into arcs, rings, or multiple images) of an image caused by light bending through a gravitational field, as predicted by Einstein's general theory of relativity.

relativity of simultaneity

The phenomenon whereby two spatially separated events that are simultaneous according to one observer (i.e. happening at the same time in his/her frame of reference), may occur at two different times according to another observer, provided the second observer is moving relative to the first.

length contraction

The shortening of an object along its direction of motion as its speed approaches the speed of light, as measured by an observer not moving with the object.

time dilation

The slowing of a clock as its speed approaches the speed of light as measured by an observer not moving with the clock. or The slowing of a clock as it approaches a massive object as measured by an observer not moving with the clock.

Special Relativity

Theory explains that the laws of physics are the same at all frames of reference, therefore the speed of light is constant regardless of the motion of the light source.

Speed of light

c = 300,000,000 m/s