order of Einstein's ideas

[gib65]

In what order did Einstein conceive of the following principles:

 

c is the universal speed limit.

E = mc^2

SR

GR

 

I'm wondering because certain sources tell me that c being the universal speed limit was the very first of Einstein's insights, but I always thought this followed from SR. That is, SR says that as one approaches the speed of light (on a spaceship), time on that ship will "halt" as judged by an observer not on the ship. It follows from this that, because time cannot get any slower than "halted", c must be a universal speed limit.

 

If Einstein came up with the universal speed limit idea first, what was his basis for this?

[RyanJ]

In what order did Einstein conceive of the following principles:

 

c is the universal speed limit.

E = mc^2

SR

GR

 

I'm wondering because certain sources tell me that c being the universal speed limit was the very first of Einstein's insights' date=' but I always thought this followed from SR. That is, SR says that as one approaches the speed of light (on a spaceship), time on that ship will "halt" as judged by an observer not on the ship. It follows from this that, because time cannot get any slower than "halted", c must be a universal speed limit.

 

If Einstein came up with the universal speed limit idea first, what [i']was[/i] his basis for this?

 

Well, at the time of that everything was believed to move realtive to an aether. When this was dissproved by an experiment (I will not bore you the with the deatils of the experiment though...) people were stuck... The Einstein came along and started to think of what would happen near to the speed of light - he them came to the idea that Light has a constant speed and every other reference frame moves relative to light.

 

A good book that explained the above well to me was a book by Kip Thorne (sp?) called "Blackholes and time warps" and it did a very good job at explaining it

 

E = MC²: I have no idea where how came up with this...

 

I think that Special Relativity was devised either from C being constant or the other way arround I'm not really shure

 

General Relativite: This was Einstein's way of combining Special Relativity and gravity and this time was much more complec but was proven in that explained exactly the orbit of Mercury whereas the Newtonian one had failed. I think it was Einstein's unique way of looking at things that inspired him to use a geometrical system to show how gravity bends space and time (Spacetime) and I think it was the only solution as to expain gravity in conjunction with SR.

 

Again I'm not an expert (No-where near) - I'm shure if you Google for Special Relativity, or General Relativity you'll find some more informaiton and I'm also shure the Physics Experts will be able to help you too!

 

Cheers,

 

Ryan Jones

[swansont]

In what order did Einstein conceive of the following principles:

 

c is the universal speed limit.

E = mc^2

SR

GR

 

I'm wondering because certain sources tell me that c being the universal speed limit was the very first of Einstein's insights' date=' but I always thought this followed from SR. That is, SR says that as one approaches the speed of light (on a spaceship), time on that ship will "halt" as judged by an observer not on the ship. It follows from this that, because time cannot get any slower than "halted", c must be a universal speed limit.

 

If Einstein came up with the universal speed limit idea first, what [i']was[/i] his basis for this?

 

As was implied by RyanJ, c as a speed limit is a conclusion of relativity, not a starting point. c is a constant in all inertial frames, and that was a part of electrodynamics (Maxwell's equations require it for EM waves). Einstein applied it to kinematics, and time dilation and length contraction are the results. The solutions diverge at v=c, and the solutions for v>c are unphysical, hence the conclusion is that c is the speed limit for massive bodies.

[[Tycho?]]

As was implied by RyanJ, c as a speed limit is a conclusion of relativity, not a starting point. c is a constant in all inertial frames, and that was a part of electrodynamics (Maxwell's equations require it for EM waves). Einstein applied it to kinematics, and time dilation and length contraction are the results. The solutions diverge at v=c, and the solutions for v>c are unphysical, hence the conclusion is that c is the speed limit for massive bodies.

 

c as a constant is a conclusion of SR? How can that be, since c as a constant to all observers is one of the postulates of SR. How would you write the theory without that as a postulate?

 

E=mc^2 is a result of special relativity, he wrote a paper on it the same year as the SR paper.

 

GR was 10 years after SR, basically adds gravity to SR.

[gib65]

'']c as a constant is a conclusion of SR? How can that be, since c as a constant to all observers is one of the postulates of SR. How would you write the theory without that as a postulate?

 

That's not what Swansont said. He said that c as a speed limit is the conclusion, but c as a constant is a postulate.

[[Tycho?]]

That's not what Swansont said. He said that c as a speed limit is the conclusion, but c as a constant is a postulate.

 

Whoops, failed to distinguish between the two.