Stanford University

Einstein’s General Theory of Relativity | Lecture 1

Lecture 1 of Leonard Susskind’s Modern Physics concentrating on General Relativity. Recorded September 22, 2008 at Stanford University.

This Stanford Continuing Studies course is the fourth of a six-quarter sequence of classes exploring the essential theoretical foundations of modern physics. The topics covered in this course focus on classical mechanics. Leonard Susskind is the Felix Bloch Professor of Physics at Stanford University.

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  • the way it all connects is the forces in which it produce, wheather magnetic or electrical or combustion it all is formed and morphed by a spark. a wise man once said time and space is one and the same, as time is of man then man him or herself is of space. 7.8hz is the magnetic frequency of earth but take in deeper and it is of man's consciousness as well.

  • I'd personally say down would be positive not negative, and as you go into the middle of our system you reach a differential proposals of a new possitive. like a framework going positive to negative as distance is reached

  • one question with the cloud of particles. If they are falling equally and will not change position, I agree if no other forces are involved. but is there any instance of this in the natural universe. is there such thing as something with 0 force acting on it? is there anything in the universe that isn't changing position? what if they fell forever what would eventually happen to that cloud of particles? would they end up orbiting or something like that? could this be calculated knowing the exact mass and nuclear forces involved? and has this calculation been done? isn't out galaxy spiralling through space time? how fast are we travelling? is gravity the consequence of the acceleration difference between space time and the speed at which our physical universe is moving with respects to each particle.

  • is it too far-fetched to propose that space-time curvature can be the inverse of the gravitational influence of mass? let's say if mass curves space-time "negatively" can something curve it "positively"? and wouldn't that be a possible cause of dark energy?

  • Lol the questions are astounding, Stanford graduates… wow, they're struggling to grasp high school physics, how did they get in there? just shows that the only difference of students getting into a good university or bad, is how much they bang out, they have no life in high school and revise 24/7 but when it comes to understanding something they don't get it, asking stupid questions, you can tell straight away these are not going to be good physicists after they graduate, they cant think. Susskind is just loosely stating key fundamental concepts that everyone should already know and be confident with, they're questioning him as if this was some new topic they're learning and as if he's wrong , how are they going to cope with general relativity if they cant grasp Newtonian physics? Really bad quality to have when becoming a real life physicist.

  • Personally, my favorites demonstration of the difference between the strength of gravity and electromagnetism is this: Put a paper clip on a table. Pick it up with a small refrigerator magnet. The WHOLE EARTH is pulling it down and this little magnet is out- pulling all that gravity to pull it up.


    Quanta of Energy + Quanta of Energy (E + E) = An Energy Density

    Density of Energy = Density of Matter

    A Density of Matter + Earth's Gravitational Force/Energy of Attraction = Weight.

    Apple & Earth

    ALL Particles of Energy/Matter exert a gravitational field of attraction, and the sum of the energy particles within the apple = its density of matter.

    And the overall density of the apples matter serves to define the strength of the apples surrounding gravitational field.

    Quite simply The Apple is one object and the Earth is another object

    And the gravitational field of each of the two objects Is exerting a a gravitational force of attraction towards the other object.

    Hence an infinitesimal apple relative to the vast size of the Earth appears to be falling towards the Earth, but is in fact being pulled towards the Earth’s surface and towards the Earths molten magnetic core – centre of gravitation.

    However as the Apple cannot pass – is restricted from passing through the Earth’s surface;

    The sum of the force of the Apples gravitational attraction towards the Earth + the sum of the force of the Earths gravitational attraction towards the Apple

    = the sum of the weight of the Apple on the Earth's surface, in essence the same as the attraction between two magnets.

    Quantum Theory is correct, apart from the fact that they Graviton's are not messenger particles but rather they are the "attractant – gravitational" particles that go into the recently discovered Gravitation waves; which appear in two dimensions as waves, which is why they have been interpreted as such, but in three dimensions of space are spirals of energy.

    Which is why when you drop a feather from a height here on Earth, it rotates as it falls.

    And additional it creates the centrifugal force that causes molten drops of lead or steel, to become perfectly spherical ball bearings, during their descent from a great height, towards the Earth’s surface.


    It should be noted and remembered that ""no one!!!"" was aware at the time that AE came up with/published his theory in 1915, in regard to gravity and acceleration, that astronauts and objects become weightless, and float in outer space, even while travelling at great speed in orbit around the Earth. However even this does not serve to explain why he totally contradicted himself in regard to the speed of light and mass?

    In the original text of the theory AE used a lift as his hypothetical acceleration structure with a person in the lift shining a beam of light across the lift.

    Einstein stated in regard to the force of acceleration that, If the lift was taken into outer space and then accelerated, the acceleration of the lift would cause the beam of light shining across the lift to bend under the force of the lifts power of acceleration.

    A beam of light is comprised of trillions of energy particles called Photons, and when you switch on a torch the photons shoot forward like speeding bullets, travelling at a speed of 300, 000 kilometers per second.

    Therefore in order for the torch beam to bend under the power of the lifts acceleration, the atomic mass of the lift and its contents would have to out-accelerate the 300, 000 kilometer speed of the photons of the light beam.

    Which Einstein always maintained was totally impossible.

    So why is it that he contradicts himself in regard to mass and the speed of light?


    Quote Albert Einstein: If the facts do not fit the theory – change the facts

    (""And the Laws of Physics""!)

    Einstein’s Theory of Relativity and Time

    Imagine that you are dreaming and in your dream you are back in your mothers’ womb warm snug and simply floating in space, and as you look around all you can see is a diffuse light.

    What time is it?

    Where are you?

    Who or what are you?

    You are no when; as there are no clocks and therefore no such thing as time:

    You are nowhere, as there are no landmarks or places to be:

    You are no one, because you do not know what you are: You only know that you exist because you think you exist, and as you think you exist, you therefore know you do exist;

    But Time most certainly does not