Albert Einstein published his Special Theory of Relativity in 1905, which established that the laws of physics are the same in all non-accelerating frames of reference, and that the speed of light in a vacuum is independent of the observer's motion. This introduced fundamental changes to how space and time were viewed. After further developing his theory over 10 years to include acceleration, Einstein published his theory of general relativity in 1915, establishing that gravity is a distortion of spacetime caused by massive objects. The theories of special and general relativity form the basis of modern physics.

1. 24 February 2020
Theory of Relativity
Group 1:
Al-Mustapha M Nasidi
Fatima Zannah Mustapha
Aisha Aminu
Nuhu Ezra
Abdulsamad Idris Ishaq

2. 2
Introduction
 In 1905, Albert Einstein
changed our perception of the
world forever.
 He published the paper "On
the Electrodynamics of Moving
Bodies".
 In this, he presented what is
now called the Special Theory
of Relativity.
Ann.Physik 17
(1905), 891-921.
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3.  The theory of special relativity explains how space
and time are linked for objects that are moving at a
consistent speed in a straight line. One of its most
famous aspects concerns objects moving at the
speed of light.
 Simply put, as an object approaches the speed of
light, its mass becomes infinite and it is unable to go
any faster than light travels. This cosmic speed limit
has been a subject of much discussion in physics,
and even in science fiction, as people think about
how to travel across vast distances.
Pune, 1 October 2005 3

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The Special Theory of Relativity
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 The theory of special relativity was developed
by Albert Einstein in 1905, and it forms part of
the basis of modern physics. After finishing
his work in special relativity, Einstein spent a
decade pondering what would happen if one
introduced acceleration. This formed the
basis of his general relativity, published in
1915.

5. 524 February 2020
 In 1905, Albert Einstein determined that the
laws of physics are the same for all non-
accelerating observers, and that the speed of
light in a vacuum was independent of the
motion of all observers. This was the theory
of special relativity. It introduced a new
framework for all of physics and proposed
new concepts of space and time.

6. 624 February 2020
 Einstein then spent 10 years trying to include
acceleration in the theory and published his
theory of general relativity in 1915. In it, he
determined that massive objects cause a
distortion in space-time, which is felt as
gravity.

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 Einstein started with a simple observation
involving a magnet and a conductor in relative
motion.

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 He noted that in both cases, an identical
electric current is induced on the conductor.
 It is not the case that the moving object
always induces a current on the stationary
one (that would be "reciprocity" rather than
"relativity").
 From this, he argued that only relative motion
is physically meaningful: hence the laws of
physics are the same in all (inertial) frames of
reference.
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 Next he added a startling corollary. The
speed of light, being of fundamental
importance in physics, must be the same in
all reference frames.
 He realised that this was "apparently
irreconcilable" with requiring that the laws of
physics are the same in all frames, but then
showed that it was perfectly consistent.
 And as a consequence, the concept of ether
would turn out to be "superfluous".
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“The laws of physics are the same
in all inertial frames.“
“The speed of light is constant in
all frames."
The Postulates of the Special Theory of Relativity
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Influence on Modern Physics
 Today, fundamental physics is formulated in
the language of Relativistic Quantum Field
Theory.
 This (difficult!) subject combines the
postulates of Special Relativity with those of
Quantum Mechanics.
 The result is the "Standard Model" of particle
physics, that in principle explains every
interaction in nature not involving gravity.
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 What can we learn from Einstein’s style of
research?
 He was motivated by logic, clarity and
physical meaning. And he had no great love
for mathematics.
 But it would be wrong to deduce that he was
strongly experiment-driven. Indeed, he said:
"A theory can be proved by experiment; but
no path leads from experiment to the birth
of a theory.”