Andrei Dmitriyevich Linde (Russian: Андре́й Дми́триевич Ли́нде; born March 2, 1948) is a Russian-American theoretical physicist and the Harald Trap Friis Professor of Physics at Stanford University.

He worked at CERN (European Organization for Nuclear Research) since 1989 and moved to the United States in 1990, where he became professor of physics at Stanford University.

In 2014 he received the Kavli Prize in Astrophysics "for pioneering the theory of cosmic inflation", together with Alan Guth and Alexei Starobinsky.

These interactions became different from each other only gradually, after the cosmological phase transitions which happened when the temperature in the expanding Universe's became sufficiently small.

This idea attracted much attention because it could provide a unique solution to many difficult problems of the standard Big Bang theory.

However, as Guth immediately realized, this scenario did not quite work as intended: the decay of the false vacuum would make the universe extremely inhomogeneous.

In 1981, during a seminar by Stephen Hawking on quantum gravity, Linde developed another version of inflationary theory that he called "new inflation".

Most of them arose because of the standard assumption that the early universe initially was very hot, and inflation occurred during the cosmological phase transitions.

In 1982-1983, Steinhardt, Linde and Alexander Vilenkin realized that exponential expansion in the new inflation scenario, once it begins, continues without end in some parts of the universe.

Quantum fluctuations produced during eternal chaotic inflation are so large that they can easily push different parts of the universe from one vacuum state to another, and even change the effective dimensionality of spacetime.

By analyzing the slow-roll inflation mechanism that initially generated the quantum fluctuations, the scientists could estimate the number of resulting universes at 10^10^10^7.

In 2000, Raphael Bousso and Joseph Polchinski proposed using the regime of eternal inflation and transitions between many different vacua in string theory for solving the cosmological constant problem.

[2] Then Michael R. Douglas and his collaborators [clarification needed] estimated that the total number of different stringy vacua can be as large as 10500, or even more, [vague] and Leonard Susskind developed the string theory landscape scenario based on investigation of cosmological phase transitions between different string theory vacua.

[5] In July 2012, Linde was an inaugural awardee of the Breakthrough Prize in Fundamental Physics, the creation of physicist and internet entrepreneur Yuri Milner.

In 2014, he was a co-recipient, with Alan Guth and Alexei Starobinsky, of the Kavli Prize awarded by the Norwegian Academy of Science and Letters.