Christie’s is to auction a series of letters from Albert Einstein’s to Michele Esso, his closest friend.

The two met while studying in Zurich in the late 1800s and would later work together at the patent office in Bern (where Einstein had his Eureka moment). 

Besso and Einstein became friends at university in the late 1800s 

Besso is also listed as Einstein’s sole collaborator on his ground-breaking first four papers.

The star lot is a letter dated July 29, 1953 that relates to the concept of “Time’s Arrow”. It’s valued at £80,000-120,000 ($101,776-152,664).

Einstein explains that our concept of the flow of time has no bearing on reality and that the big bang occurred independently of it.

He writes: “I think that it is the same in all cases, i.e. that time's arrow is absolutely bound to thermodynamic conditions.

“If the fundamental series of events [of the universe] depended on time's arrow, then the appearance of a thermodynamic equilibrium would be absolutely incomprehensible'.”

A lot of the letters address similarly weighty concepts, but others are concerned with the day to day minutiae of relationships, family and Jewish life.

A letter of condolence to Besso’s family from March 21, 1955, valued at £30,000-50,000 ($38,166-63,610), rounds off the correspondence.

It finishes on a profoundly uplifting sentiment: “Now he has again preceded me a little in parting from this strange world.

“This has no importance. For people like us who believe in physics, the separation between past, present and future has only the importance of an admittedly tenacious illusion”.

An increasing number of Einstein letters are hitting the market as demand pushes prices up.

Earlier this week a letter to his friend David Bohm referencing his lack of faith in God sold for $84,000 – more than four times its $20,000 estimate.  

We have a signed letter from Albert Einstein for sale.

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