* 1939 – Albert Einstein and Leó Szilárd write a letter to Franklin D. Roosevelt, urging him to begin the Manhattan Project to develop a nuclear weapon.

Left: just before the appearance of a Bose – Einstein condensate.

A Bose – Einstein condensate ( BEC ) is a state of matter of a dilute gas of weakly interacting bosons confined in an external potential and cooled to temperatures very near to absolute zero.

This state of matter was first predicted by Satyendra Nath Bose and Albert Einstein in 1924 – 25.

A record cold temperature of 450 ± 80 pK in a Bose – Einstein condensate ( BEC ) of sodium atoms was achieved in 2003 by researchers at MIT.

It can also be found in Fermi – Dirac statistics ( for particles of half-integer spin ) and Bose – Einstein statistics ( for particles of integer spin ).

At very low temperatures in the vicinity of absolute zero, matter exhibits many unusual properties, including superconductivity, superfluidity, and Bose – Einstein condensation.

Note that the above formula is only applicable to classical ideal gases and not Bose – Einstein or Fermi gases.

His half-brother was Charles Einstein ( 1926 – 2007 ), a writer for such television programs as Playhouse 90 and Lou Grant.

In the classical limit, i. e. at large values of or at small density of states — when wave functions of particles practically do not overlap — both the Bose – Einstein or Fermi – Dirac distribution become the Boltzmann distribution.

Velocity-distribution data of a gas of rubidium atoms, confirming the discovery of a new phase of matter, the Bose – Einstein condensate.

Left: just before the appearance of a Bose – Einstein condensate.

A Bose – Einstein condensate ( BEC ) is a state of matter of a dilute gas of bosons cooled to temperatures very near absolute zero ( or ).

This state of matter was first predicted by Satyendra Nath Bose and Albert Einstein in 1924 – 25.

The result of the efforts of Bose and Einstein is the concept of a Bose gas, governed by Bose – Einstein statistics, which describes the statistical distribution of identical particles with integer spin, now known as bosons.

EPR ( Einstein – Podolsky – Rosen ) paradox

* Bohr – Einstein debates

* Penrose, Roger: " Singularities and time-asymmetry ", Chapter 12 in General Relativity: An Einstein Centenary Survey ( Hawking and Israel, editors ), ( 1979 ), see especially section 12. 3. 2, pp. 617 – 629 ( ISBN 0-521-22285-0 )

Nearly simultaneously David Hilbert published " The Foundations of Physics ", an axiomatic derivation of the field equations ( see Einstein – Hilbert action ).

* Einstein – Hilbert action

* Einstein – Hilbert equations

Albert Einstein and his colleagues Boris Podolsky and Nathan Rosen ( known collectively as EPR ) designed a thought experiment intended to reveal what they believed to be inadequacies of quantum mechanics.

", authored by Einstein, Podolsky and Rosen in 1935, condensed the philosophical discussion into a physical argument.

Though the EPR paper has often been taken as an exact expression of Einstein's views, it was primarily authored by Podolsky, based on discussions at the Institute for Advanced Study with Einstein and Rosen.

Einstein, Podolsky and Rosen asked how can the second particle " know " to have precisely defined momentum but uncertain position?

However, the principle of locality appeals powerfully to physical intuition, and Einstein, Podolsky and Rosen were unwilling to abandon it.

Bell, On the Einstein – Poldolsky – Rosen paradox, Physics 1 195-200 ( 1964 ).

* A. Einstein, B. Podolsky, and N. Rosen, Can quantum-mechanical description of physical reality be considered complete?

* Selleri, F. ( 1988 ) Quantum Mechanics Versus Local Realism: The Einstein – Podolsky – Rosen Paradox.

* The Einstein – Podolsky – Rosen Argument in Quantum Theory ; 1. 2 The argument in the text ; http :// plato. stanford. edu / entries / qt-epr /# 1. 2

* Stanford Encyclopedia of Philosophy: " The Einstein – Podolsky – Rosen Argument in Quantum Theory " by Arthur Fine.

Research into quantum entanglement was initiated by a 1935 paper by Albert Einstein, Boris Podolsky, and Nathan Rosen describing the EPR paradox and several papers by Erwin Schrödinger shortly thereafter.

The counterintuitive predictions of quantum mechanics about strongly correlated systems were first discussed by Albert Einstein in 1935, in a joint paper with Boris Podolsky and Nathan Rosen.

In this study, they formulated the EPR paradox ( Einstein, Podolsky, Rosen Paradox ), a thought experiment that attempted to show that quantum mechanical theory was incomplete.

Schrödinger intended his thought experiment as a discussion of the EPR article — named after its authors Einstein, Podolsky, and Rosen — in 1935.

Lorentzian wormholes known as Schwarzschild wormholes or Einstein – Rosen bridges are connections between areas of space that can be modeled as vacuum solutions to the Einstein field equations, and which are now understood to be intrinsic parts of the maximally extended version of the Schwarzschild metric describing an eternal black hole with no charge and no rotation.

In this spacetime, it is possible to come up with coordinate systems such that if you pick a hypersurface of constant time ( a set of points that all have the same time coordinate, such that every point on the surface has a space-like separation, giving what is called a ' space-like surface ') and draw an " embedding diagram " depicting the curvature of space at that time, the embedding diagram will look like a tube connecting the two exterior regions, known as an " Einstein – Rosen bridge ".

The analysis of the radial geodesic motion of a massive particle into an Einstein – Rosen bridge shows that the proper time of the particle extends to infinity.

Timelike and null geodesics in the gravitational field of a Schwarzschild wormhole are complete because the expansion scalar in the Raychaudhuri equation has a discontinuity at the event horizon, and because an Einstein – Rosen bridge is represented by the Kruskal diagram in which the two antipodal future event horizons are identified.

These results suggest that all observed astrophysical black holes may be Einstein – Rosen bridges, each with a new universe inside that formed simultaneously with the black hole.

In the Einstein – Cartan – Sciama – Kibble theory of gravity, however, it forms a regular Einstein – Rosen bridge.

Instead, the collapsing matter on the other side of the event horizon reaches an enormous but finite density and rebounds, forming a regular Einstein – Rosen bridge.

In the Einstein – Cartan theory, however, it forms a regular Einstein-Rosen bridge ( wormhole ) with a new, growing universe on the other side of the event horizon.