Paul Halpern
@phalpern.bsky.social
Physicist and Science Writer. Author of eighteen books, most recently The Allure of the Multiverse: Extra Dimensions, Other Worlds, and Parallel Universes
Pinned
Paul Halpern
@phalpern.bsky.social
· Nov 25
A holiday gift for those who have it all
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
'I think and think for months, for years. Ninety-nine times the conclusion is false. The hundredth time I am right.'
-Albert Einstein,
From 'The Einstein Theory of Living,' New York Times, March 12, 1944: nyti.ms/2BfmRlD
-Albert Einstein,
From 'The Einstein Theory of Living,' New York Times, March 12, 1944: nyti.ms/2BfmRlD
December 27, 2025 at 5:16 PM
'I think and think for months, for years. Ninety-nine times the conclusion is false. The hundredth time I am right.'
-Albert Einstein,
From 'The Einstein Theory of Living,' New York Times, March 12, 1944: nyti.ms/2BfmRlD
-Albert Einstein,
From 'The Einstein Theory of Living,' New York Times, March 12, 1944: nyti.ms/2BfmRlD
The Horn Antenna in Holmdel, New Jersey
Using that instrument, Arno Penzias and Robert Wilson accidentally discovered the persistent radio hiss that had a profile consistent with relic radiation from the Big Bang, cooled down over billions of years.
#histSTM
Using that instrument, Arno Penzias and Robert Wilson accidentally discovered the persistent radio hiss that had a profile consistent with relic radiation from the Big Bang, cooled down over billions of years.
#histSTM
December 27, 2025 at 5:14 PM
The Horn Antenna in Holmdel, New Jersey
Using that instrument, Arno Penzias and Robert Wilson accidentally discovered the persistent radio hiss that had a profile consistent with relic radiation from the Big Bang, cooled down over billions of years.
#histSTM
Using that instrument, Arno Penzias and Robert Wilson accidentally discovered the persistent radio hiss that had a profile consistent with relic radiation from the Big Bang, cooled down over billions of years.
#histSTM
One is never too old to master a new creative endeavour.
Wolfgang Amadeus Mozart waited until he was 5 years old until he had the age and experience needed for musical composition.
Wolfgang Amadeus Mozart waited until he was 5 years old until he had the age and experience needed for musical composition.
December 27, 2025 at 5:12 PM
One is never too old to master a new creative endeavour.
Wolfgang Amadeus Mozart waited until he was 5 years old until he had the age and experience needed for musical composition.
Wolfgang Amadeus Mozart waited until he was 5 years old until he had the age and experience needed for musical composition.
Reposted by Paul Halpern
A holiday gift for those who have it all
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
November 25, 2025 at 12:36 PM
A holiday gift for those who have it all
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
Reposted by Paul Halpern
Richard Feynman on String Theory:
'I have noticed when I was younger that a lot of old men in the field couldn’t understand new ideas very well...
I’m an old man now, and these are new ideas, and they look crazy to me, and they look like they’re on the wrong track.'
#Physics #Feynman #Science
'I have noticed when I was younger that a lot of old men in the field couldn’t understand new ideas very well...
I’m an old man now, and these are new ideas, and they look crazy to me, and they look like they’re on the wrong track.'
#Physics #Feynman #Science
November 25, 2025 at 12:38 PM
Reposted by Paul Halpern
'The universe does not exist "out there" independent of us. We are inescapably involved in bringing about that which appears to be happening. We are not only observers. We are participators. In some strange sense this is a participatory universe.'
-John Archibald Wheeler
#science #physics
-John Archibald Wheeler
#science #physics
June 25, 2025 at 10:56 PM
Reposted by Paul Halpern
I swore an oath to the Constitution in 1986. I've upheld it through 25 years of service and every day since I retired.
If Trump's trying to intimidate me, it won’t work. I’ve given too much to our country to be silenced by bullies who care more about power than the Constitution.
If Trump's trying to intimidate me, it won’t work. I’ve given too much to our country to be silenced by bullies who care more about power than the Constitution.
November 24, 2025 at 8:27 PM
I swore an oath to the Constitution in 1986. I've upheld it through 25 years of service and every day since I retired.
If Trump's trying to intimidate me, it won’t work. I’ve given too much to our country to be silenced by bullies who care more about power than the Constitution.
If Trump's trying to intimidate me, it won’t work. I’ve given too much to our country to be silenced by bullies who care more about power than the Constitution.
Reposted by Paul Halpern
The President doesn't want you standing up and speaking out against him, so he's coming after me to intimidate all of us.
But I won't back down — and neither should you.
But I won't back down — and neither should you.
November 26, 2025 at 7:51 PM
The President doesn't want you standing up and speaking out against him, so he's coming after me to intimidate all of us.
But I won't back down — and neither should you.
But I won't back down — and neither should you.
Reposted by Paul Halpern
Reposted by Paul Halpern
'I rarely think in words at all. A thought comes, and I may try to express it in words afterwards.'
-Albert Einstein
(From a conversation with psychologist Max Wertheimer in 1916)
#Einstein #science #physics #ScienceSky
-Albert Einstein
(From a conversation with psychologist Max Wertheimer in 1916)
#Einstein #science #physics #ScienceSky
June 5, 2025 at 1:49 PM
'I rarely think in words at all. A thought comes, and I may try to express it in words afterwards.'
-Albert Einstein
(From a conversation with psychologist Max Wertheimer in 1916)
#Einstein #science #physics #ScienceSky
-Albert Einstein
(From a conversation with psychologist Max Wertheimer in 1916)
#Einstein #science #physics #ScienceSky
Reposted by Paul Halpern
Today is UK publication day for my new book *Discordance: The Troubled History of the Hubble Constant* To celebrate, I’m posting an essay on the trailblazing women who transformed our understanding of the universe. open.substack.com/pub/jimbaggo...
The Harvard Computers
The trailblazing women who transformed our understanding of the universe
open.substack.com
October 23, 2025 at 7:14 AM
Today is UK publication day for my new book *Discordance: The Troubled History of the Hubble Constant* To celebrate, I’m posting an essay on the trailblazing women who transformed our understanding of the universe. open.substack.com/pub/jimbaggo...
Reposted by Paul Halpern
"Baggott’s book is a masterpiece that combines depth with clarity and comprehensiveness with readability,” says renowned historian of physics Helge Kragh in his review of my new book ‘Discordance’. 😳 www.nature.com/articles/d41...
Why we still don’t understand the Universe — even after a century of dispute
Despite huge breakthroughs, astronomers still can’t agree on what the cosmos is made of, much less how it came to be. A fresh account delves into the reasons.
www.nature.com
October 20, 2025 at 7:36 PM
"Baggott’s book is a masterpiece that combines depth with clarity and comprehensiveness with readability,” says renowned historian of physics Helge Kragh in his review of my new book ‘Discordance’. 😳 www.nature.com/articles/d41...
Reposted by Paul Halpern
Tributes at Bryn Mawr College to the brilliant mathematician Emmy Noether, who spent her final years there. Noether revolutionized the methods of modern physics by identifying continuous symmetry groups with conservation laws. The third image is her grave marker.
#Science #Mathematics #Physics
#Science #Mathematics #Physics
November 12, 2025 at 11:57 AM
Tributes at Bryn Mawr College to the brilliant mathematician Emmy Noether, who spent her final years there. Noether revolutionized the methods of modern physics by identifying continuous symmetry groups with conservation laws. The third image is her grave marker.
#Science #Mathematics #Physics
#Science #Mathematics #Physics
Reposted by Paul Halpern
Annual holiday tradition:
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
November 20, 2025 at 8:45 PM
Annual holiday tradition:
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
Reposted by Paul Halpern
'Strange is our situation here upon earth.
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
November 20, 2025 at 8:51 PM
'Strange is our situation here upon earth.
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
Reposted by Paul Halpern
Pair it with a good Martini for a Christmas you won't forget.
Great book.
Great book.
November 25, 2025 at 7:11 PM
Pair it with a good Martini for a Christmas you won't forget.
Great book.
Great book.
Richard Feynman on String Theory:
'I have noticed when I was younger that a lot of old men in the field couldn’t understand new ideas very well...
I’m an old man now, and these are new ideas, and they look crazy to me, and they look like they’re on the wrong track.'
#Physics #Feynman #Science
'I have noticed when I was younger that a lot of old men in the field couldn’t understand new ideas very well...
I’m an old man now, and these are new ideas, and they look crazy to me, and they look like they’re on the wrong track.'
#Physics #Feynman #Science
November 25, 2025 at 12:38 PM
A holiday gift for those who have it all
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
November 25, 2025 at 12:36 PM
A holiday gift for those who have it all
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
The Allure of the Multiverse
An extraordinary voyage into the history of parallel universes, higher dimensions, and time travel in speculative science and imaginative fiction.
Available at:
amazon.com/Allure-Multi...
hachettebookgroup.com/titles/paul-...
Reposted by Paul Halpern
The Allure of the Multiverse
Expand your mind with a fantastic voyage into the strange history of parallel universes, higher dimensions, and time travel—from mystic musings to quantum conjectures and hidden realms beyond cosmic frontiers
www.amazon.com/Allure-Multi...
Expand your mind with a fantastic voyage into the strange history of parallel universes, higher dimensions, and time travel—from mystic musings to quantum conjectures and hidden realms beyond cosmic frontiers
www.amazon.com/Allure-Multi...
November 12, 2024 at 5:51 PM
The Allure of the Multiverse
Expand your mind with a fantastic voyage into the strange history of parallel universes, higher dimensions, and time travel—from mystic musings to quantum conjectures and hidden realms beyond cosmic frontiers
www.amazon.com/Allure-Multi...
Expand your mind with a fantastic voyage into the strange history of parallel universes, higher dimensions, and time travel—from mystic musings to quantum conjectures and hidden realms beyond cosmic frontiers
www.amazon.com/Allure-Multi...
'Strange is our situation here upon earth.
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
November 20, 2025 at 8:51 PM
'Strange is our situation here upon earth.
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
Each of us comes for a short visit, not knowing why, yet sometimes seeming to divine a purpose..
There is one thing we do know: that man is here for the sake of other men.. upon whose well-being our own happiness depends.'
-Albert Einstein
#ScienceSky
Richard Feynman and Julian Schwinger, two of the recipients of the 1965 Nobel Prize in Physics and both New Yorkers, were intellectual rivals
Schwinger would assert that he never used Feynman diagrams
Feynman would pretend to students that he couldn't pronounce Schwinger's name
#ScienceSky
Schwinger would assert that he never used Feynman diagrams
Feynman would pretend to students that he couldn't pronounce Schwinger's name
#ScienceSky
November 20, 2025 at 8:47 PM
Richard Feynman and Julian Schwinger, two of the recipients of the 1965 Nobel Prize in Physics and both New Yorkers, were intellectual rivals
Schwinger would assert that he never used Feynman diagrams
Feynman would pretend to students that he couldn't pronounce Schwinger's name
#ScienceSky
Schwinger would assert that he never used Feynman diagrams
Feynman would pretend to students that he couldn't pronounce Schwinger's name
#ScienceSky
Annual holiday tradition:
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
November 20, 2025 at 8:45 PM
Annual holiday tradition:
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
Thanksgiving Turkey Feynman Diagram, drawn by particle physicist Yuhsin Tsai:
quantumdiaries.org/2009/11/26/t...
#HappyThanksgiving #LHC #physics
Reposted by Paul Halpern
One of Albert Einstein's best friends in his later years was mathematician Kurt Gödel, who found a strange rotating universe model that allowed for backward time travel, and presented it to him on his birthday.
Note that the idea was purely hypothetical, and has no known connection with reality.
Note that the idea was purely hypothetical, and has no known connection with reality.
November 16, 2024 at 10:22 PM
One of Albert Einstein's best friends in his later years was mathematician Kurt Gödel, who found a strange rotating universe model that allowed for backward time travel, and presented it to him on his birthday.
Note that the idea was purely hypothetical, and has no known connection with reality.
Note that the idea was purely hypothetical, and has no known connection with reality.
Tributes at Bryn Mawr College to the brilliant mathematician Emmy Noether, who spent her final years there. Noether revolutionized the methods of modern physics by identifying continuous symmetry groups with conservation laws. The third image is her grave marker.
#Science #Mathematics #Physics
#Science #Mathematics #Physics
November 12, 2025 at 11:57 AM
Tributes at Bryn Mawr College to the brilliant mathematician Emmy Noether, who spent her final years there. Noether revolutionized the methods of modern physics by identifying continuous symmetry groups with conservation laws. The third image is her grave marker.
#Science #Mathematics #Physics
#Science #Mathematics #Physics
Reposted by Paul Halpern
'The existence and validity of human rights are not written in the stars..
A large part of history is therefore replete with the struggle for those rights.. in which a final victory can never be won.
But to tire in that struggle would mean the ruin of society'
-Albert Einstein
#Einstein #Science
A large part of history is therefore replete with the struggle for those rights.. in which a final victory can never be won.
But to tire in that struggle would mean the ruin of society'
-Albert Einstein
#Einstein #Science
October 13, 2025 at 2:14 PM