Unit 7

THE SOLAR SYSTEM & BEYOND:THE PHYSICS OF THE UNIVERSE

EARTH

SOLAR SYSTEM

• how physicist measure the universe and what tools

• theoretical and experimental• the what’s, the why’s and the how’s of the

universe

THE THEORY OF

RELATIVITY

ALBERT EINSTEIN

• proposed a theory that revolutionized at how we look at the universe

• He published his Special Theory of Relativity in 1905

Special Theory of Relativity

E= mc²E= energym= mass

C= constant

Two years later……-Einstein worked on the second part of his theory, the General Theory of Relativity-he proposed a new model for the gravitational force of the universe.

An object in outer space will warp the dimension of space time. A body near this object will move in accordance to the shape of the wrapping which is conical.

The cone becomes more pronounced as the body becomes more massive. Eventually if the body is massive enough, the body will wrapped the spacetime grid such that the body will be crunched inside the cone to produce a singularity.

If this happens, a Black hole is created.

The Special Theory of Relativity

• Einstein predict in this theory that the ultimate constant in the universe.

• represented by the symbol C• speed of the light is measured exactly today• it is the speed that is observed no to change• uniformity of the light was conceived

GALILEO GALILEI• suggested this fact in the

17th century• unification of Maxwell’s

electro magnetic theory• substantial fractions of

the speed of the light, the calculations of length, time and other quantities become erroneos

HENDRIK LORENTZ

• introduced a factor (now known as the gamma factor) that will subsequently be proven experimentally

• the factor was introduced

If v<<c, then the factor 1 - v²/c² is approximately equal to one. Hence, y=1 for velocities that we encounter every day and this

factor is negligible and everything will be reduced to the original equations of Newton.

v= velocity of the bodyc= curse is the speed of

light

Length ContractionThe consequence of the introduction of the Lorentz factor or the Lorentz transform is that for body moving at a substantial fraction of the speed of life, its length is shortened when it is observed by an observer outside its reference frame (we will call it “an outside observer”)

Time Dilationanother consequence is that for an outside observer, the time of the moving body will run slower

The ultimate consequence of the special theory of relativity is that there is a speed limit in a universe

matter in any event cannot approach the speed of light

Several Consequences that the General Theory of Relativity has to offer: