70 years on - where would the world be without Hirohito

 No, that is not correct under UK (British) law. Let me clarify the actual position and then answer the Einstein part.

UK copyright duration (as of 2025)Copyright in the United Kingdom (and the rest of the European Union) for literary, dramatic, musical, and artistic works (which includes scientific papers) lasts for:70 years after the author’s death (post mortem auctoris, or pma).

• This has been the rule in the UK since 1 January 1996 (when the EU “70 years pma” term was harmonised).
• Before 1996 it was 50 years pma, but the longer term was applied retrospectively to works still in copyright in 1995.

There is no requirement in UK or EU law that a work must have been “commercially exploited” or that a business must have “generated understanding of the original text” for copyright to continue. Once created and fixed, copyright exists automatically for the full term regardless of whether the work is published, used commercially, or falls into obscurity.Special cases:

• Typographical arrangements (the publisher’s layout of a published edition) have a shorter term: 25 years from first publication.
• Crown copyright or parliamentary copyright can have different rules (usually 50 years), but this does not apply to Einstein’s papers.

Einstein’s papers and E=mc² (1905 and later)Albert Einstein died on 18 April 1955.Under current UK/EU law:

• Copyright in his scientific papers expires 70 years after his death, i.e. on 31 December 2025 (the end of the 70th calendar year).
• After midnight on 1 January 2026, all of Einstein’s writings (including the 1905 Annus Mirabilis papers, his later works, letters, etc.) will enter the public domain in the UK, EU, and all other life+70 countries.

Current status (December 2025):

• In the UK and EU: still technically under copyright for a few more weeks.
• In the United States: Einstein’s 1905 papers have been public domain since 1995 at the latest (pre-1929 publication = public domain in the US, or at the latest 95 years from publication for later papers).
• In life+50 countries (e.g. some parts of Africa, Asia): already public domain for decades.
• In life+70 countries (UK, EU, Australia, Canada now also life+70, etc.): still copyrighted until the end of 2025.

So in a few weeks (January 2026), all of Einstein’s papers, including the original E=mc² paper (“Ist die Trägheit eines Körpers von seinem Energieinhalt abhängig?”, Annalen der Physik, 1905), will be fully public domain worldwide in practically every major jurisdiction.They are not “open source” in the software sense (that term doesn’t really apply), but they are about to become completely free of copyright restrictions everywhere that matters.