# Einstein and Lorentz

I am hoping someone can help me with something. I want to go into the field of temporal physics and I was wondering if someone could help me understand why Einstein's E=mc2 isn't combined with Lorentz's factor ϒ=1/√1-(v2/c2) to further prove the light-speed barrier?

## Answers and Replies

Nugatory
Mentor
I was wondering if someone could help me understand why Einstein's E=mc2 isn't combined with Lorentz's factor ϒ=1/√1-(v2/c2) to further prove the light-speed barrier?

Both of these relationships are derived from the same underlying assumptions (the two postulates of special relativity - Google for "On the electrodynamics of moving bodies" to find Einstein's 1905 paper on SR) as the light-speed limit. Thus, using them to "further prove" the lightspeed limit doesn't tell us anything new; it just shows that the assumptions that lead to the light-speed limit lead to the light-speed limit.

ChrisVer
Gold Member
Also the relation $E=mc^2$ is already given at a certain Reference fram (the rest frame of the object of mass $m$ ). So how would you put a gamma factor?

T
Both of these relationships are derived from the same underlying assumptions (the two postulates of special relativity - Google for "On the electrodynamics of moving bodies" to find Einstein's 1905 paper on SR) as the light-speed limit. Thus, using them to "further prove" the lightspeed limit doesn't tell us anything new; it just shows that the assumptions that lead to the light-speed limit lead to the light-speed limit.
Thank you for the reference, Nugatory. Also, could you recomend any books or sights that are credited and discus the possibility of Tachyons?

Khashishi
Science Advisor
Jorlack, you are right. One way of writing the energy equation is
##E=\gamma m c^2##
The common equation ##E=mc^2## is only valid for particles at rest, when ##\gamma = 1##.

Jorlack, you are right. One way of writing the energy equation is
##E=\gamma m c^2##
The common equation ##E=mc^2## is only valid for particles at rest, when ##\gamma = 1##.
##\gamma = 1## when the velocity of the said object or particle is 0. Therefore the Lorentz factor would equal ##1/1## or simply, 1.