Joseph Conlon
@JosephPConlon
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Physicist (string theory), writer and poet (Origins:The Cosmos in Verse, @oneworldnews Nov 2024). New College, Oxford; writing represented by The Wylie Agency.
Oxford, UK
Joined October 2015
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By a village cricket green - could there be a more English dedication?
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"I have not thought at all about physics during the entire last month and I don't know if I still understand anything of it"
Heisenberg, in 1925
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As a reminder, the biggest discovery of 20th century biology occurred in a physics laboratory.
Using Physics as your template for how science works makes you stupid about science. Physics is a weird little science with a very simplistic causal structure. It’s fundamental laws are universal. They operate always and everywhere. No other science is like that.
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I can confirm this indeed blows up ones notifications.
But, in case of doubt or misunderstanding, string theory is absolutely the deepest, most consequential and most likely to be true set of ideas about what sits at the intersection of the Standard Model and quantum gravity.
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Skip the lot and read this instead!
If you're curious about quantum mechanics but tired of pop, hand-wavy books, here are 10 serious books that helped me.
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Much toil, many publications and long calculations: but the thing I have written with most reach remains Chapter 7 from my 2015 book Why String Theory? on the enduring intellectual value of string theory.
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No, `theoretical evidence' is like getting the below expression from two different theories and thinking that perhaps this hints at a deep relation between the two.
"Theoretical evidence" is is a term of art in string theory that does not mean evidence in the sense we usually think of it in science. It means "we haven't found a counterexample to this mathematical conjecture so far".
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The undergrad view of theoretical physics is short calculations that are conceptually neat and explain important facts about nature.
This is because undergrads learn physics at a Nobel Prize/week.
Actual researchers know they are lucky to write one such paper in their career.
"Most of the physicists at Harvard and MIT don't even realize that what they're doing is not physics at all, not even science, really."
Brief, provocative, plausible rant by
@alexeyguzey
. I've no idea whether it's accurate.
Do you?
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Or if you haven't time to read it, just buy it.
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A great truth of modern physics which is simple to state, but profound in its implications:
No 'fundamental particle' is fundamental. Instead, we now understand them as excitations of an underlying quantum field.
Particles are excitations.
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Another Fermi question for 1st years:
An earthquake occurs off the coast of Japan. Twelve hours later, waves from it are detected in Los Angeles. How deep is the Pacific ocean? 1/3
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The stupid obscurantist notation which deliberately muddies one of the most important, beautiful and simple (rightly understood) discoveries of the human species: the equations of the Standard Model.
What part of this equation do you not understand? ✍️
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Another Fermi problem. The neutron has a radius of 10^-15 m and is made of one up (charge +2/3) and two down (charge -1/3) quarks. Estimate (a) its mass and (b) its electric dipole moment 1/4
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Thread on string cosmology. Daily additions until the review is out.
22 Jan: Why string cosmology?
1. Cosmology offers highest known energy scales: best(?) chance to probe string theory.
2. Cosmology is all about gravity: thus a chance for quantum gravity theories to add value.
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And, finally, it is out! Several points (1/5)
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Galaxy clusters are amazing objects. Despite the thousands of galaxies, the galaxy mass is less than that of the gas between them. The gas has a density of less than a particle per cubic cm, but a temperature of hundreds of millions of degrees. 1/2
Below is a 3D mass distribution of a galaxy cluster. The 'pinnacles' are the galaxies, sitting on a huge underlying bulge of mass
The vast majority of the mass of the cluster is in the *empty space* between the galaxies
What could possibly explain this measurement 🤔
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Arxiv trailer: great and fun collaboration with great people, on string cosmology in the era between inflation and big bang nucleosynthesis.
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Where does string theory/quantum gravity matter?
Some people think Planck-scale physics is automatically decoupled from observation. Even some particle physicists think Planck-scale physics is automatically decoupled from observation.
But both are wrong (two examples).
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Sometimes Sabine does serious stuff but this is straight click-bait. Putting scare-quotes around something which explains, to high precision, lots of high-quality data (eg CMB) is not good science.
The idea of “dark matter” has been around for a century, but researchers have thus far failed to detect even a single particle of if. What if dark matter exists but it interacts so rarely with our detectors that we will never be able to measure it?
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@postdocforever
Given physics studies systems from single particles to 10^23 particles, from atoms to the universe, the idea that it’s a niche approach which doesn’t generalise is odd (and not historically true)
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My favourite email from Oxford Physics is the one asking the whole department if they knew the origin of a small casing, labelled Uranium with a metal pellet inside, found at the back of a desk drawer in the Nuclear Physics building.
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Another fun Fermi question for 1st years: What is the maximum size of a raindrop? 1/3
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@_merajhasan
The idea of phase transitions is a physics idea about complex systems which provides an excellent conceptual framework for e.g understanding political change.
More social scientists should understand these.
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This is some weird intellectual inferiority complex.
Opinions on string theory get stronger with decreasing knowledge about the subject (and what on earth is ‘applied quantum mechanics’)
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Physics mischief! Which is the only particle that someone successfully named after themself?
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Yesterday I had a wonderful and rare experience in the physics department.
Someone asked if I was a student.
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Now that the moment of his death has passed, a (slightly delicate) thread on Peter Higgs, football and contributions to physics. As everyone knows, Peter Higgs is famous for the proposal of the Higgs boson, discovered at CERN in 2012. Why bring football into this? 1/6
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And I say to you, there is more joy in heaven over one academic dean who repents than over ninety-nine academic deans who need no repentance.
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What theoretical evidence looks like, for the smart-alecks who lob paper aeroplanes at the math teacher
For those at the back who haven't been paying attention: there is no such thing as "theoretical evidence".
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Reflecting that one of the great virtues of learning quantum mechanics is seeing how strange and complex truth can be, as a vaccine against all the many ideologues with simple pat theories of the world.
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Another Fermi question: estimate the size and mass of the Earth.
I often use this as a week 1 question, and tell students to use as little technology as possible.....
....which doesn't stop answers involving aeroplanes, satellites and the like.
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Another 1st year Fermi question: find the surface tension of water.
(In the raindrop question I generally allow them to just use this number)
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If Heisenberg didn't know what a matrix was, Born took a week of intensive thought to recognise one...
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I’ll be polite and describe this as ignorant.
The astro example he gives is almost exactly equivalent to what any new collider is guaranteed to do.
Particle physics has a problem. While astronomers know that a bigger telescope will find interesting stuff, even if it just involves getting spectra of things we have only been able to image before, there is no guarantee that a bigger particle accelerator will find *anything*.
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How weak is the gravitational force?
With your little finger and its electromagnetic nerve impulses, you can pick up a pen *against the combined downward gravitational pull of THE ENTIRE EARTH*, one thousand billion billion tonnes of it acting together to oppose you.
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(insert here) = quality journals.
Having been in my field for 20 years I can't think of a single piece of important work published in either Nature or Science.
@PhysRevLett
has some good stuff but also publishes a lot of the worst papers, hype written for cites.
But Eric, we already did that. We have ‘a small number of high quality journals, with strong editors’ embedded in a vaster sea of lower impact factor journals with weaker editors. E.G.
@Nature
@ScienceMagazine
@PhysRevLett
++embedded in a sea of (insert here). No need to reinvent
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Important to keep in mind: the mainstream is almost always wrong.
(If you doubt this, look back to mainstream views of >50 years ago, and see how much survives)
That’s because getting at truth is a bloody hard business.
Important to keep in mind: Contrarians are almost always wrong.
They’re worth listening to for the very rare case when they aren’t.
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Another Fermi problem: estimate the length scale of quantum gravity.
This is a good problem with beginning first years, because it seems so ridiculous that they can think about it, but it provides an entry into dimensional analysis. 1/2
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The biggest objection to the monarchy, it seems, is that it only works in practice but not in principle.
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Academic careers are built on three elements:
1. Talent/ability at something (important to know one's own relative strengths)
2. Hard work / effort
3. Good luck/good timing (in being around 'hot' topics)
A high score on two of these three is necessary.
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Some people always misunderstand this, but my book is a defense of string theory as by far the deepest and most intellectually serious approach to quantum gravity.
The more you learn of it, the less sceptical you become.
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It's listed on Amazon so I guess it is now public news.
I have a poetry book coming out; the early universe told in verse.
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Everything is physics.
Academics, if you are not actively bringing the second law of thermodynamics and your lived experience of it into your teaching, you give a false sense of the human condition.
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When this paper first appeared, I was confident it would get 50 citations and hopeful it would get one hundred (and also thought the scenario would be killed within a year)
Vijay Balasubramanian, Per Berglund, Joseph P. Conlon and Fernando Quevedo's 2005 JHEP article
"Systematics of moduli stabilisation in Calabi-Yau flux compactifications"
reaches 1,000 citations.
#topcites
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The story of string theory from 1968 to 1973, as a possible theory for the strong interactions, is fascinating. See Matt, or my book, or both :)
Did you hear
#physicists
simulated a baby
#wormhole
in a lab? Well, it's even MORE TRUE that
#StringTheory
and
#ExtraDimensions
were discovered in the '60s. Think I'm joking? I'm not. To learn what's true/false in the wormhole story, start with this.
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@Mate_Kapovic
This makes no sense to me. There are lots of slightly obscure English words I don’t know and may use incorrectly. If I confuse a jib-boom with a bowsprit I am using the language incorrectly.
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The Middle East: I'm not going to post about what should happen over the next day(s), or my (non)-experience of military rules of engagement, dealing with terrorists or hostage situations.
But I will talk about something relevant in my area, SESAME. 1/7
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The referee's wrong as a factual statement, but physics is about experiment (or rather, data). My biggest worry about string theory is the number of people in the subject who do think that experiment is a dirty word, and the declining fraction who are identifiably *physicists*.
I share quotes from grant referee reports, so you all can see how the anti-fundamental science philosophy has entered academia:
"String vacua, AdS/CFT correspondence and other theoretical approaches of this sort, are not aligned with what physics is all about, experiments."
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Excellent 5-year position in theoretical physics for early career researchers (PhD after August 2022) at All Souls in Oxford. Note early deadline of September 6th
Similar positions available in Mathematics, Classics, Modern Languages, Politics
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A short thread on nothing: one of the subtlest concepts in all physics.
What, or where, is nothing?
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Having been over every line > 50 times and having read every line out loud > 10 times, the final read before the book goes to the printers.
@OneworldNews
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My own experience of research, across my career, is that 90% of progress occurs in 10% of the time (i.e. most of the time I am either stuck or unclear what to do). It's not and never has been a comfortable situation, but at least time has made it familiar.
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The swampland (and its conjectures) has revolutionised string phenomenology and particle theory....
...in a similar way that flying cars have revolutionised commuting.
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Quantum mechanical emission lines tell us about the gas makeup — and, on top of this, there is also the unknown dark matter.
Overall rough mass fractions: about 5% in galaxies, 15% in intracluster has, about 80% dark matter
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Pleased to see
@QuantaMagazine
take back some of this. Although the researchers take most of the responsibility, Quanta also needs more diversity in who they talk to, to escape subfield social bubbles where everyone cheers on everyone else.
The researchers behind the new work — some of the best-respected physicists in the world — frequently and consistently described their work to us as “creating a wormhole.” Independent researchers not directly connected to the research also described it as such. (6/10)
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When I've attended poetry readings, part of me feels they could do with more Russian physicists in the audience.
i.e. a bit less of 'Wow! So moving! Simply wonderful!' and a bit more of 'That 4th line is awkward and doesn't scan, while your second poem made no sense to me.'
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My book Origins: The Cosmos in Verse appears Nov 7th
@OneworldNews
: the early universe as never before, a modern creation epic.
If you review poetry/pop science/literary non-fiction etc and would like a review copy, please drop me a note by email/DM.
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5-year positions for early career researchers (here = PhD viva after 1st Aug 2022) in Theoretical Physics (or Mathematics, or Archaeology, Classics, Modern Languages, Politics -- 1 for each subject).
Deadline 6th September
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Courtesy of DALL-E, 'young physicist in the swampland'. I don't know where it is sourcing the bow-tie and braces from...
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Me trying to negotiate a path between the Scylla of N=(2,0) theory in 6d and the Charybdis of Swampland Spectacular Signatures Today!
String theory is often critiqued for being divorced from reality. It predicts not one universe, but 10^500 of them. But theorist
@JosephPConlon
says the attacks are unjust.
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This, by
@CamilleRalphs_
, is good. And funny, serious in an unserious sort of way, if that makes sense.
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The oddness of this is that it is precisely the Strings conference Frenkel spoke at, and it’s heavily IAS-centric themes, that represents the strongest institutional obstacle to studying the physics of this universe.
Here one can look for guidance to the sages of the past, such as Richard Feynman. They liked mathematical models but never lost sight of the big prize: understanding the physics of THIS Universe. And I think that's still a good guiding principle for today's physicists. 5/5
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SESAME is almost the only place in the world where Iran and Israel participate as common members of a single entity.
And with it, it speaks for what physics (and science) can do for peace. 4/7
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The good thing about single-authored papers is that you get to indulge yourself without collaborators to restrain you.
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@martinmbauer
I think basically yes; e.g. Klebanov-Strassler is a standard example of a solution describing a confining gauge theory, i.e. one which is not globally AdS and does run with energy scales. So you don't need strict AdS/strict CFT to use the correspondence,
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This then becomes a trigonometry problem to find the radius of the earth: and then assuming uniform density (any density between water and iron is fine) - they get a mass for the Earth.
Also a good chance to correct false history about e.g. mediaeval flat earth beliefs. 3/3
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As recognised in all the best books on string theory
@WhyStringTheory
The hard part is figuring out what kind of problems you are best suited for
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@Mate_Kapovic
If I say the 4th planet is Jupiter because I mistake it with Mars then yes that’s wrong.
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But when the opportunity fell for him in the mid-1960s, he took it gloriously: and for that, thank you Peter and you will always be remembered. The analogy is not quite perfect, but you are to UK physics what Sir Geoff Hurst was to football. 6/6
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Physics has no battalions and no heavy armour -- but it does offer an image of what can be possible in a better world.
And so as a physicist, while I will sometime comment on politics, one of the best things I can do for peace is to continue to post Fermi problems. 7/7
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It’s not going to be me, but over the next few years someone should live tweet, a hundred years on, day by day, the discovery of quantum mechanics.
ESPECIALLY when Heisenberg writes that he hasn’t thought about physics for 3 months and is unsure whether he still understands it.
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The difficulty is that one person's bullshit is another one's ambergris.
The scientific community should be much less tolerant of bullshit than it is. Collegiality is not an excuse.
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And if you want a verse treatment of her life and discoveries, see my upcoming book Origins: The Cosmos in Verse
Cecilia Payne-Gaposchkin at the desk, Harvard College Observatory, c. 1920s.
Payne was the first person to determine that stars are primarily made of hydrogen and helium. In 1925, she became the first person to receive an astronomy Ph.D. from Harvard.
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@nattyover
For the same reason we don't say the LHC creates quantum black holes and experimentalists study their Hawking radiation: via holography, heavy ion collisions are dual to black holes in some gravity theory.
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The theorist’s viva nightmare:
Maths questions 😂
Theoretical physics 👍
Astronomy😳
Resolving power of a Fabry-Perot interferometer 😟
Resolving power of a microscope 🥵
So, Mr Heisenberg, do you even know how a battery works?🥶
Wien gave him an E grade and wanted to fail him!
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This question is a good introduction to surface tension and how different sources of energy scale in different ways with volume.
Through surface tension, it can also lead into discussions of nuclei and nuclear fission, neutron stars and black hole mergers and GW emission. 3/3
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Whenever I read about students moving into /abandoning a subject based on comments from faculty, I feel a temporary weight of impossible responsibility for every throw-away / uninformed / misinterpreted thing I have ever said to a student.
And then I move on :)
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What are the single words, where the fact that someone understands the word tells you a lot about them?
example: Hagoromo
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This sort of stuff gives string theory a bad name.
Only Quanta Magazine would think of asking Cumrun Vafa for a quote on cosmological observations using BAO and supernovae.
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This one is quite open-ended and can go in various directions, but the idea is to get students using dimensional analysis and thinking about what can determine the speed of water waves (and also about the physical differences between ocean waves and ripples on a pond). 2/3
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Short reflection on politics and physics.
In 1905, Henry Campbell-Bannerman became the most powerful man in the world while Albert Einstein was an unknown patent clerk.
Who changed the world the most? Who is now unknown?
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Physics (and science) is one of the great unifying languages of the world; it brings together people from all backgrounds and can act as a bridge across barriers of nationality, religion and culture. 5/7
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Just done a telephone interview with a journalist on whether film characters can pass through wormholes/hyperspace and their relationship to extra dimensions in string theory.
What can possibly go wrong?
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@ChrisLangan6
It’s brilliant - called Why String Theory - best book I ever wrote on the subject.
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Son watching TV after school. A paper from Classical and Quantum Gravity appears. WTF, thinketh I. Paper involves ‘warp bubbles’ which apparently relate to the Ascension of Christ and the Pyramids. But, physicists, be not afraid, for
@michiokaku
was interviewed to explain it all.
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Finishing a PhD/1st postdoc in strings / particle physics / astoparticle / other areas too!
Like research but also enjoy outreach and want to combine the two?
Think of the below, and think of applying with Oxford.
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Estimating the electric dipole moment is fun, as the measured answer is zero to a level ten billion times smaller than the estimate. This then leads to a fun introduction to the strong CP problem. 4/4
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