The String Theory Wars and What Happened Next
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String theory was a beautiful idea, the best contender for a theory of everything that we have seen so far. Thousands of physicists spend decades trying to work it out. But it didn’t quite go according to plan. String theory became extremely controversial during what's been dubbed the “String Wars” about 20 years ago. Then it kind of disappeared. What happened? What were the string wars? And what are string theorists doing now? That’s what we’ll talk about today.
This video comes with a quiz: quizwithit.com/start_thequiz/...
At 13:41 the guy on the bottom right is Peter Woit, not a second Lee Smolin, sorry about that.
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#science #physics
00:00 Intro
00:49 A dream come true
03:45 The trouble begins
09:39 The string wars
15:06 AdS/CFT
20:19 Up to today
22:54 Summary
23:20 Stay safe with NordVPN
This video comes with a quiz: quizwithit.com/start_thequiz/1709895855140x478935412148797440
I have to refuse to take your quiz until you address my claims all your climate change data has been altered. Therefore all predictions derived from the data is incorrect.
You invest in Francaise De l'Energie and then start wearing more expensive clothes all of a sudden? Poor you, you must be afraid of having potentially made the wrong guess.
DIPOLE ELECTRON FLOOD THEORY replaces all other sub atomic nuclear bit theories. I will take the quiz will you respond? I say protons are made of 1823 dipoles and neutrons are 1824. I have experiments using lasers and venturis that CRUSH fields same as colliders but can squirt a stream of Electron Neutrinos like a hose. dipoleelectronflood.com/the-theory/
String Theory is NOT a THEORY Don't you smart clever physicists have a specific definition of the word "Theory"? Like "well-substantiated" backed by "laws" with the ability to make predictions and test it? I wish you "science communicators" would get your communication straight! Others great exampled We don't know Dark Matter is anything to do with Matter! You guys have observed what appears to be a Gravitational effects.... Just using the word "Dark" is NOT an excuse for "Matter" ditto Dark Energy? The "Force" of Gravity.... Is it actually a force? Have you guys found the mediation particle... The Graviton? How about you smart people have a little get together over a coffee and agree some terms that are clear and not misleading! And don't get me started on "Planets",.... Sticking to a word based on "wandering star" and having to do linguistic gymnastics to make up a group that puts Mercury with Jupiter!
@@mikelivingood7797 Kind of a bizarre "threat". I doubt anyone cares if you take the quiz.
Ironically, the future of String Theory is hanging by a thread.
one could say they strung us all along, spun a great yarn.
You could still get a lot of funding if you know someone who can pull some strings
String theory is still correct, none of this propaganda makes any difference.
@@james6401 JA,JA,JA!...
@@annaclarafenyo8185-An untestable theory isn’t a theory. It’s a mathematical model
To note on the fact that many physicists aren't trained in philosophy of science: When I got my undergrad degree in physics (class of 2019), we were required to take philosophy of science as a core requirement for our physics program. I found out recently that they removed that requirement after much complaint from physics students (apparently mostly because the course required students to write a lot of essays... something i found my colleagues weren't too fond of). It's a shame because philosophy of science is such an important aspect in checking scientists on their claims and their work.
Tertiary education is becoming too money focused, I found a lot of local universities doesn’t teach you hard part because of the complaints from students (lower satisfaction reduces relevant staffs’ benefits). Though I can understand in that short amount of time you have to study all days to get pass, yet somehow I feel university isn’t supposed for everyone. Maybe if something like tafe provides higher quality practical course that are acknowledged by the business owners, it can help the situation. But again a lot of people in uni need to scam moneys to do the research.
Once you realize basically all modern science in the West has eschewed philosophy as an optional + valueless elective, much like selfish + immature students in a school, it makes a whole lot of sense of how things are going!
I remember Leonard Susskind making fun of a philosophers of science in his TED talk a few years ago.
Exactly. Philosophy should be required in all majors because if you don’t know how to ask questions, how can you expect the correct answer?
I agree with them. I hate essays.
I was a PhD student and postdoc in mathematics in the early 00's. My specialty was more computer oriented than physics. I still got caught up in this. At some point I said that a theory that could not make predictions about the real world wasn't actually science. This resulted in me not being offered a tenure track position at the end of my postdoc and I got no other interviews for tenure track positions.
That's brutal, I'm sorry that the academic world is like this. I hope you are still able to do research in your field.
I tried to go into academia at my alma mater in the early 10s. However, I didn’t have time to be a lab assistant or a teaching assistant, and I intended to take night classes. Although I had recommendations from the school’s ex-dean and current profs, as soon as the dean found this out, he scolded me for being a spoiled brat and personally rejected me. Instead, I went to Silicon Valley, and the rest is history. Dodged a bullet.
Why did the dean consider you spoiled? Because you couldn't be a lab or teaching assistant? why would that make you spoiled? That sucks, but glad you are doing well without going through academia@@unvexis
Don't be sorry my friend, you have preserve your honesty and your self-respect. I have a news for you that you are vindicated - TOE exists and you can find it in the book - "Theory of Everything in Physics and The Universe"
@@valentinmalinov8424 Take your lunacy elsewhere. You are not my friend.
I love it that "String Theory" is written in Papyrus font. String theory really seems like a relic from the era in which Papyrus font seemed cool.
I'm educated but not a PhD level at math but I've always kept up with what's going on ever since I stole a copy of bhot when I was 12 in 1990. As well as a layman can anyway. It never seemed to hold any water with me and soured me on on the topic for a long time. I'm a software engineer so my education level was (known to me as) woefully lacking but it always seemed like a game of telephone to me where reputation was more important than the work. I felt second hand embarrassment for the whole community that I'd grown to have so much respect for. I still have as much respect but any snowball that rolls long enough is bound to get covered in shit and common sense never allowed me to buy into it. I realize I'm very under qualified to even have an opinion but my love for the cosmos and the excitement of people unlocking it's secrets is probably why I took to programming computers for fun and buying math books to create particle simulations and such in my passtime and since I retired at 35 I've been obsessed with electronic engineering and a regimented guitar practice schedule since I have the time haha. I'm going to go back to school this fall and take ee, I have almost 2 years worth of math credits that carry over. I was going to challenge a bunch of the theory courses but decided against it as I've always loved learning. I don't even have a beer anymore because I find it dulls my curiosity and makes me procrastinate if I'm designing circuits. I'd like to specialize in fpga development as I've always been obsessed with logic and bitwise solutions to tough coding challenges. Some of the best programmers I've ever met were physics grads I tutored in c their first year in university. I used to do people's assignments for free because playing guitar at an advanced level taught me that I had to practice to be good at something. I am a much better musician than programmer these days as I'm so into learning ee theory and donating learning kits to people who ask nothing worse than wanting to learn something and not being able to afford it. We have all these content creators making people think learning anything is trivial these days but do nothing besides collect gear they'll never use when it can give someone a start so if a person is in canada or the us I send them kits tailored to their goals and if they stick with it I buy them better gear. It's made me realize how suspicious people are of good deeds and how laziness can keep them from getting a new oscilloscope. I've had folks beg me for more gear and they couldn't even use ohms law to work out resistors in series or parallel. That's my only catch if they want more than the 400 worth of stuff I've already mailed them. I ramble. Sorry. Mental ilness with full faculties I think may be worse than the bliss of ignorance sometimes. I never lie, even though I can't shut up when im tired haha.
I thought that opposite String Wars was going to be String Trek. That's where String Theory went wrong.
Ha, wish I'd thought of this 😅
@@SabineHossenfelder did you hear about the small string theory experiment that was sent outside the solar system in the 70s? It was called String Trek: Voyager if I recall. Ok I'll leave
The can have conventions and eventually crown a Lord of the String.
String theory is still around but mostly used in the music industry.
String trek to boldly calculate where no physics has been before
12:00 reminded me how some PhD students were telling me that if you want to be quoted, make a mistake. everyone will want to correct you, but that does not matter, because the counter goes up
😂😂😂😂😂😂😂😂
Same for KZhead videos. Make a mistake, everyone hops in the comments and pumps up the stats for you
I heard a story about someone who did that on Reddit. Ask for a solution on something and you get no responses, give an incorrect solution and everyone will jump in to give you the right one
This is Cunningham's law
Well Eric Lerner could tell you about that. But you have to make a big splash. He's been against the Big Bang for years. Mainstream science ignored him. Then he gave "Crisis in cosmology," substance, with predictions after the JWST. His paper was commented on by anyone and everyone. Going as far as to say, ""crank science and conspiracy theory." He really wanted to debate the questions. No one would touch that. Eric is a smart cookie, no one wanted to be embarrassed by the so called "hack. "
Peter Woit was my undergraduate thesis advisor at Columbia. I feel so fortunate to have had that opportunity, and I learned so much! He has an excellent blog called Not Even Wrong.
Great guy. He could have played along with this string stuff and gotten tenure at Columbia or elsewhere. But he chose to stand by his principles.
The One String: One string to rule them all, one string to find them, One string to bring them all and in the darkness bind them.
In the land of anti De-Sitter space where the equivalencies lie
Was never a fan of Laws of the String
typical Calabi-Yau haters.
@@facepalm486 ???
Quite clever
I have a lot of respect for you for getting out when you realized that the theory wasn't panning out.
And we are thankful, that she makes these great videos instead for us now.
To be honest, string theory was always a bit of a stretch.
@@aarondavis8943 🥁
@@aarondavis8943 then it got all tangled up, which was knot funny
Which is ok for a couple of years and a few physicists around the world. But not at the scale it actually happenend.
String theory involved a lot of complex math to make everything fit. It just made me think of epicycle theory of planetary motion, back when the natural philosophers (pre-scientist) thought the Earth was the center of the universe.
Apt comparison…
Earth is the Center of the Universe. The Observable Universe that is.
This is what I was coming to say. Tweaking it constantly to fit feels like epicycles. If it can always be tweaked to fit, it can never be falsified. Where a better theory predicts new things that can be checked experimentally.
exact same observation is made in Lee Smolin's book
So, do we have an ellipse equivalent somewhere in physics that was initially dismissed for being less elegant, but which is far more elegant than string theory with all the fixins? Or has no one heard of it because Galileo is writing pamphlets about how the people doing the actual experiments are lucky to find their own backside with both hands?
Full credit to Lee Smolin and Peter Voit, for shouting out loudly that the String Theory emperor had no clothes. It takes courage to lead a charge against firmly entrenched powers.
I love the dissection of fundamental particles because it seems a little like the time and effort to determine how many angels can dance on the head of a pin.
If someone constantly thinks about AdS/CFT, everything looks like AdS/CFT.
Think I’ll just Sitter this one out.
Nothing looks like AdS/CFT except AdS/CFT. It's a very specific thing that is unimaginably constraining.
@@annaclarafenyo8185 Of course. This is not only the problem of cosmic constant wrong sign of the but also finite versus infinite universe.
If my income depends on everything looking like AdS/CFT you bet your a** that I'll make sure eeeeveerything looks like AdS/CFT.
Maybe ads/cft was the friend we made along the way
It never explained why my running shoes kept untying.
Maybe there's a particle for it
You need higher friction shoe laces. Or you need to tighten them
You could get those curly laces that don't need to be tied to keep your shoes on securely. It's a mistake to assume knots are necessary to explain how to walk.
that's explained in knot theory.
You need flat laces. They have more friction to keep themself under tension. You can also adjust your laces more precisely w/ flat laced.
Sabine throwing shade at Susskind was the icing on the cake for me. And she just keeps going in. Max Planck is now my second favorite scientist. Hossenfelder renewed my faith in honest, rational evaluation. That's what I feel the sciences _should_ be about. For that, she will always be best girl.
A longer video of Sabine, like the good old times! 🎉 Thank you so much for your hard work ❤
Frei nach Harald Lesch: Wenn man mit manchen String-Theoretikern redet und die Probleme der Theorie anspricht kriegt man das Gefühl man redet mit einem Künstler: "Was? Ihnen gefällt mein Kunstwerk nicht? Verlassen Sie sofort mein Atelier!"
Aber auch Harald Lesch und Josef Gaßner tuen alles, um Sabine im deutschen Sprachraum totzuschweigen. Ich nenne das wissenschaftliche Inquisition.
Guter Vergleich!
Absolutely.
They're in love with the 'beauty' of their maths with no interest in reality.
Harald Lesch und Josef Gaßner sorgen aber genauso wie andere dafür, dass Sabine im deutschsprachigen Raum totgeschwiegen wird und keine Anstellung bekommt. Für mich ist das wissenschaftliche Inquisition.
Sabine is so enjoyable. I love how she envisions the entire picture and doesn't ramble off into esoteric minutiae guaranteed to confuse instead of inform...;) As always, her sense of humor permeates "everything" and makes the inscrutable so easy to understand!
Thank you for the quiz. I found it to be really helpful to reinforce what you discussed in the video. 😊
Straight talk! Fantastic to communicate these ideas and controversies to us non specialists.
This is the most comprehensive, accurate, and honest recap of the string theory situation and the state of theoretical physics to date.
There is much more to theoretical physics than string theory. Condensed matter, astrophysics, quantum information etc are examples of huge areas of theoretical physics with almost nothing to do with string theory.
@@raghavdeshpande3415 string theory looks like a major bust…like the Ptolemaic description of the solar system.
What happened to loop quantum gravity?
Eric Weinstein did it better
No it’s not, lmfao. 😂
"Whatever happened to string theory?" It purported to explain everything. And then folks found out it could explain anything.
One key fits all kind of idea
@@k9876k yep. Made it worthless/unfalsifiable 😆
@@k9876k String theory is The One Ring To Bind Them.
I finally understand why string theory isn't talk about as much anymore, I thought I was living under a rock to not hear about it. lol
This is a fantastic exposition with a very detailed look at how an idea, when explored fully, went from science to science fiction.
It rather went from science fiction to pseudoscience. 😀 Sadly, with billions of invested public money. There was a rather historical break in theoretical physics, when serious old-school quantum field theorists rather suddenly got out of fashion, when Regge-theory, S-matrix theory, pomerons, strings and the like entered the scene and took over for some years, with people such as Chew, Frautschi, and others. At that time, "axiomatic QFT" was thought to be "dead" and S-matrix-theory was thought to be the only game in town. If I'm not mistaken, String Theory and Superstring Theory somehow emerged from that.
This is the best synopsis of String Theory I have come across in the last 10 years.
lol it’s a lie. String Theory is almost completely untested. Foolish physicists made ultra-convenient easily-testable predictions in the 90s/00s, which LHC falsified. There are plenty of valid “inconvenient” string models that reproduce GR and QFT, and predict essentially no proton decay or superpartners. The 10^500 claim is also false, and proves Sabine doesn’t care about truth.
If only Peter Woit had gotten NordVPN, he wouldn't have had his identity stolen by Lee Smolin...
That was there on purpose
@@LuisSierra42 why
@@hamud7708 I was being sarcastic
@@LuisSierra42 Yes, but why?
because there was a mistake in the video, and the photos of both of them were labeled "Lee smolin" @@Lovin_It
Love your content!!! Youve inspired me to attempt to get more hands on with physics and try to understand more of the advanced mathematics involved
String Theory is an example of a theory so nice, so elegant, so absolutely beautiful, that it could only be bullshit, and yet so many people still hold it in high regard despite its failings. Truly a tragic tale.
Wittgenstein wrote “Philosophy is a battle against the bewitchment of our intelligence by means of language.” I say “Physics is a battle against the bewitchment of our understanding by mathematics.”
Love it.
We use language to make poetry about universe. Quantum physicists just try to use math instead in their poetry
Wittgenstein was right but then without language philosophy (including science) can say nothing.
@@SoulDelSol That's because math is a language
Huh, I'm no expert but on my first read through I interpreted "by means of language" to be referring to the cause of bewitchment, not the tool by which we battle it.
A always learn something from Sabine's videos, but this one is truly epic. It reviews forty years of high-energy theoretical physics and tells it in a comprehensible form. It is the first draft of a history of contemporary high-energy physics, right here.
epic, really!
Thank you, Sabine! It's always great to listen to your content.
I’m new to Sabine’s videos but these are simply brilliant. The ability to reduce complex (to put it mildly) topics to terms a Luddite like me can fractionally understand is such an impressive skill…and they’re fantastically funny in places too! Bravo and thank you 🙌
Sabine says “But what do I know, I’m just a random KZheadr“. Hardly. A relatively young researcher, with an H - index of 32 and an i10 - index of 70, she is a productive, well-respected physicist. In 2022 alone I counted seven publications in various journals, including Nature Physics (!), and four more in 2023. We’re so lucky to be able to listen to her whenever we want!
Exactly, 2024 she published a new scientific paper on arxiv about the statistical relevance of DM and MOND together with two colleagues. But she has no payed job anymore. She's remarkable busy and she's a brave heart and a beautiful mind.
...she was joking 🙂
@@Bramps66She was joking, that´s right, but there´s a bit of salt in it, cause here in her homeland, she doesn´t get a payed job anymore. It´s a kind of scientific inquisition.
There is nothing that says that a random sample can't be well above average. She is definitely not the average KZheadr but if you are lucky you maybe have picked her at random.
@@larslindgren3846She´s simply great and she still does scientific research on physics on her own account.
String Theory is the fan fiction of physics.
lol
And CERN is the biggest, most expensive cock ring ever made.
Given that for the majority of human history, the majority of fiction was basically fanfiction that budded off and grew, I don't know if calling it "fanfiction" is a correct analogy. If anything, it's the Twilight of physics, because there was an era where it was all the rage and now the branch it's on is dying.
@@VelvetCondomsother notable fiction have had the exact same life cycle as twilight - initial huge popularity and then a never ending series of retrospectives (and likely historical analysis way down the line). In fact twilight has had a significant impact on more modern fiction in general and continues to do so even now, with the tropes it popularised. the sheer cultural impact it has had means itll never truly die, because like it or not, it is a significant part of literary history now. You could say the same thing about string theory, of course
The dominance of string theory also had to do with the fact that it's cheaper for universities to hire string theorists than experimentalist physicists and they could pump out papers faster, making it easier to rise up the academic ladder. Since more of them were hired, they had the numbers to drown out everyone else, dominate votes, and shape “mainstream” academic culture. Academics is still a human setting & trends emerge from the social dynamics.
Thank you Sabine for this excellent video again ! One of my very close friends is a well known french astrophysicist, he spent 20+ years of his life working on the string theory and he recently gave up. He can't officially talk much about his demise since he's still being paid by the CERN (and the pressure of his colleagues, his students...) but he's definitely against the project of the next "super collider". He doesn't believe that making the protons any faster will give us any satisfactory observations and doesn't believe anymore in the idea of super symetry. I'm not part of the the "scientific community" so it's easier for him to "confess" about his mistakes as a young professor and it takes a lot of courage to admit he's probably been wrong all those years... A bientôt.
I kind of had a feeling that string theory was wrong when I’d watch machio kaku and Brian Greene talk about it and only ever talk about how beautiful it is and never about how it explains experimental results
Sabine, I have a MSc and was lucky to work with academic scientists with PhDs and have come to believe that academicians are not preoccupied by truth per say but only about what they can say about it. They spend the first half of their carreers destroying existing theories and establishing new ones, and the latter half defending their theories against all newcomers.
_per se_
It is just normal animal behavior. Physicists are animals like you and me, not "winged angel heads"
Philosophy is the construction of _frameworks_ for describing reality. This leaves the field open to a lot of grifters. What makes science special among all the philosophies is that is can make extraordinarily accurate and testable predictions. If it can't, it gets tossed in the bin. Proponents of string theory protected their theory by constant alteration every time they failed at a prediction but that can only hold back the tide for so long.
@@aarondavis8943bcz most of history string theory was not physics. It is mathematical physics field, meaning study mathematical problems inspired by physical systems. As I know, nobody really cared much about application of it to physical problems last 40 years. But in popular media it is shown as physical theory, meanwhile professionals don't treat it like this since 80s.
Like everyone else they want money. Also, sometimes power plus they feel a need to be popular. Basically, the human condition.
This video hurts my brain, but I'm okay with that. It's fascinating to see how different theories gel with the evidence we find around us. 🙂 Thanks again, Sabine!
Always interesting and thought-provoking discussions here.
This video is helpful for a thread on ResearchGate that I got myself stuck in, a while ago. Also, nice Lee Smolin reference - his books are always fun to read and make me wish the Perimeter Institute had a Writers in Residence program for a poet and a fiction author to eavesdrop on conversations there. (Because Smolin et al. are just so good at analogies and images based on turning sophisticated physics into valid sentential logic).
String 'theory' is the very definition/paradigm of shifting goalposts...
I heavily missed this kind of videos, dear Sabine ❤ personally I like them better than the daily short ones.
Agreed. The daily ones felt like I was being spammed. Edit: used past tense because I unsubscribed.
This was a particularly good long video.
Ditto!!!
tbh thanks for making this video i find them very enjoyable and interesting at how things actually work behind the scenes with it all
I really do not know why people dislike this woman, she is the best. Love your explanations and your name, Sabine.
I purchased Peter Woits book the year it came out and it’s an excellent read. The title “not even wrong” a favourite putdown of Wolfgang Pauli meaning something that is not testable like Russell’s teapot.
A few years ago I met a guy who had almost finished his PhD on string theory, but suddenly quit and switched to a PhD in labour economics. He didn't explain when I asked why. It's funny, that was before I knew anything about string theory and its failures, but I already guessed that something suspicious is going on. Now I know why :)
interesting, because one of the hardest problem in political economy is finding the mathematical solution to explain price formation in the markets. The problem is so incredibly difficult that probably we have not the right math instruments just to tackle it. Marx tried to solve it (he was a good mathematician) and failed, but who succeeded in progress a very little bit was piero sraffa, an italian economist who adopted some marxian concepts, obviously rejected by the great majority of bourgeoise academic world. But he refused to introduce the real deal, the concept of labour exploitation by the owner of the means of production, because capitalist economics would be shattered to the foundations. In my opinion, official physical theories like strings, discarding alternative theories to the quantistic model, are just fake like official bourgeoise economy theories, which discard communist labour exploitation theories alternative to austrian school, keynesism, monetarism, etc.
@@zdenekburian1366 hello, are you an economist?
but how he can switch from physics straight into economics?
@@xmedian003x9they're both applications of mathematical models. There's nothing difficult in economics if you know physics
@@xmedian003x9 not in an academic sense, I study the scientific critique of political economy, that is, dialectical materialist theories, such as libertarian communism or anarchism, which are in antithesis to the innumerable, contradictory and false theories of bourgeois political economy which have always shaped the governments of all capitalist countries, today in their decadent imperialist phase, and which have brought us to the current disastrous geopolitical situation
We love you Sabine! You are great and you are doing the best thing you could do for science. Your video is not ‘too much’ at all. It’s exactly what we expect of you. And that is to be an honest and reliable - reporter and scientist. Thank you for your work on this channel and we hope you will make much more out of this particular subject. There are many of us loosing hope and feeling lost after facing the corrupt hindrances of our system. Your kind of history is not seldom at all, nor is it limited to academia. Maybe the majority of honest free thinkers doesn’t get any chance in this world. And maybe your destiny is to represent that reality, more than it is to make a scientific breakthrough. Maybe, right now, the human world is more in need of honest public speakers than scientific breakthroughs…
This is why philosophical education of researchers is extremely important. Most never read even elementary books about discovery and how to lead or fit into a research program but focus on hard skills (that often are also wrong). The most useful book, that should probably made mandatory to every starting PhD student, would be Proofs and Refutations from Lakatos. It is an eye opening short fun read that can be applied directly to any research
Thank you Sabine for another professional and informative physics video
For decades I've suspected that string theory was just a self-licking ice cream cone. I still do, but now I know it's maths-flavored ice cream.
With infinite flavors too😊
Yes, it was always a math-induced theory.
I think that if Sabine released a video next week saying that string-theory is correct, I suspect you would say you've been suspecting it to be correct for decades too. 🥴
@@VindensSagaalthough people do make similar comments either way, it's a mistake to think these are the same people
@@VindensSaga nah. Extraordinary claims require extra evidence. And string theory has a huge deficit of evidence to make up for.
Thank you Sabine, for a coherent and lucid explanation of a complex subject. Non-scientists like me are grateful!
Fantastic. Thank you for the clear explanation. I never understood why people kept working on this when it obviously was not testable.
"just one more collider bro. i promise bro just one more collider and we'll find all the particles bro. it's just a bigger collider bro. please just one more. one more collider and we'll figure out dark matter bro. bro cmon just give me 22 billion dollars and we'll solve physics i promise bro..."
Being an undergraduate in the mid-1970s it really seemed that following on from QCD and all that a ToE was just around the corner. It’s been a disappointment 50 years later that it has eluded us… 😢
We’re not as smart as we like to think.
Because we went horribly wrong at some point and that point preceded string theory. I wish there was funding and will to retest and critically (with true open mind, with "every single holy cow of physics can be slaughtered" attitude) re-examine all hypotheses and experiment results from last 120 years (from Planck onwards). And also re-do the experiments.
There are plenty of disappointments to go around in physics and engineering. I worked as an aerospace engineer in the 1960s, the Golden Age of space exploration on Gemini, Apollo Applications, Skylab, Space Shuttle. My degrees are in applied physics. Apollo 17 occurred in Dec 1972. I've been waiting over 50 years for the next humans on the Moon. That may occur within the next 3 or 4 years and I may still be around to witness that event. The big difference between my experience and that of the string theorists is that we actually did what we set out to do.
@@rays2506 I would like to borrow the words of Peter Thiel. ``We have been so distracted by advances in information technology that we have failed to notice that progress in physics and engineering has stalled``
I'm a simple engineer but enjoy physics. I was enamoured by String Theory in the 90's and particularly liked the idea of multiple dimentions. I felt (emphasis of the word felt) that it was possible that just as the 4th dimention confers mass to volume that a 5th (6th, 7th...) dimention could confer gravity to mass.
"the 4th dimention confers mass to volume" ??
the jokes in this hit harder than they should, whether it's all her or her with an editor, the funny moments just hit harder for some reaosn
14:12 Oops. Seem to have 2 Lee Smolins
Yes, sorry, I saw this too late. Put a note in the info.
There's definitely only one Lee Smolins. Great respect for an amazing mind 👍
Presumably, if you have some kind of supersymmetry going on, there would be multiple Lee Smolins.
But can you ever have enough Lee Smolins? 😉
@@7rich79Well only if the mass of the second one was much greater than the Standard Smolin.
You missed the one underlying reason why string theory took off in the first place.... quantisation. One of the most elegant possible explanations for why energy packets only occur at distinct levels is that they're actually harmonics. Pluck a guitar screen and pipe the output into an oscilloscope and you'll see frequencies at distinct levels, same idea.
Indeed, that was very appealing…
Good old guitar screens 😅
yeah the entire point of string theory was to change 0 dimensional point particles into 1 dimensional strings, that way the mass would be more evenly distributed and the infinities that come from quantizing gravity into 0 dimensional particles get avoided.
I think in the video though she explained how one of the string vibrations naturally gave rise to the graviton. Which is quantized gravity in its simplest hypothetical explanation.
Late sixties, guitars... LSD?
Thank you! I always wondered why many people rather called it a "string hypothesis" and what the chieves problems were. This was a perfect summary for a layman!
I really love this channel, seriously I appreciate you so much more than any educational institution.
Poor michio kaku! He must be devastated!
This was an absolutely brilliant episode. You're an absolutely great science communicator Sabine, and I suspect a great person as well.
Yeah she's my girlfriend and can confirm she is great 😊
I cannot understand even 10% of Sabine’s essay, but I love having the opportunity to listen to her explanations anyway 🙂.
String Theory went from "Theory of Everything" to "Theory of Nothing".
It's so helpful that Sabine keeps the physics distinct from the philosophy and the metaphysical ontology, whilst also giving us her perspective rather than simply conveying a prevailing consensus. I would love to read a history of physics by Sabine in this style.
It was a great brief summary of the history of string theory, and the fact that it is dead now.
@@blucat4 Hm, And what do you think is alive in physics? the budget?!
A history of any topic by Sabine would be compelling, with her razor sharp intelligence and delightful humour revealing the facts.
Thank you for explaining physics, I have wondered why I haven’t heard about string theory for a long time now. Now I understand.
I love your long form videos thank you sabine
Very minor point: At 13:29 you show a picture of Peter Woit (lower right) that is labeled "Lee Smolin." (I went to graduate school with Peter, where he became disillusioned with physics and decided to focus on computers at an early enough time, allowing him to stick in the math dept at Columbia for all these decades without actually being a professor for much of it.)
It's fortunate that we don't live in a Universe that A) has a negative cosmological constant, and B) the ADS CFT conjecture is incorrect (somehow). If the cosmological constant was negative, it might have taken us a _lot_ longer to find out why the conjecture was wrong, needing to find some other line of evidence that falsifies it.
Yes, you know, I've been wondering why string theorists don't just argue that the measurement for the CC is wrong and it's really negative. That would have been much more convincing.
There's perhaps another line of thought among some theorists: That the Cosmological Constant is really negative, but due to some additional "quintessence" -kind of field it appears to be slightly positive. 😊 @@SabineHossenfelder
@@SabineHossenfelder Moreover, the inflation of atoms is not observed in any experiment. Hubble and James Webb Space Telescope pose the question of the causes of the Big Bang, without proving the expansion of the Universe in any way. As a Physicist, you have to be honest, to signify the meaning or sign cosmological constant, within the framework of the unproven big bang, prematurely.
I really enjoy the context provided in this video. As a layperson attempting to expand their knowledge, it's difficult to know how seriously to take the foundational work of some of these theories. Thank you for laying it all out for us.
Having such explanations about the reality of String Theory in France is so difficult… Thanks Sabine !
Not to be shallow and easily distracted, but I loved the look of this video. The warm pink/blue background, the black dress, the lighting, your hairstyle, the fonts--it was all especially soothing to the eye. Keep it up!
7:47 Mathematically rich is scientist for “job security.”
Hi Sabine, I love your videos. From 13:25 to 13:58 the picture of Peter Woit is labelled Lee Smolin.
I'm glad you posted it, and glad I watched it.
One future physicist to another, gazing up at the sky: "Ah, the Murray Gell-Mann Memorial Nebula. We'll never get funding like that again." -- anon.
Thank you Dr. Sabine for keeping us updated about the latest and most debated topics in the field of science!
Gnädige Frau, - We cannot thank you enough for all the heavy lifting you do, and have done, in efforts to push back against the fantasy(ies) that have invaded/overrun some disciplines of the sciences.
I was a pet De-Sitter and a dog De-Walker for a long time! Loved the animals!
Hugely appreciate "whatever happened to X?" content. It's something that tends to be missing from the news, as generally there's no big event, and things just sort of fizzle out.
Nothing can better convince a person of the validity of his hypothesis than the fact that writing papers on it brings him funds for his research.
The famous Upton Sinclair quote comes to mind: "It is difficult to get a man to understand something when his salary depends upon his not understanding it."
I love your KZhead channel. There used to be physics programmes on the BBC, eg. Horizon and Brian Cox's programmes. However, there has been nothing for years. I like the way you explain things .
What I miss in this video is the role of string theory in possible insights into the quantum nature of space via holography; see e.g. Mark van Raamsdonk.
Thank you Sabina. Your review/analysis of this theory's past with specific names, dates etc. answered all the questions I've had about String theory over the past few years
The text font used in "string wars" was a nice touch...
Yes. 😎
Great video. I remember being at a university dinner in Cambridge about 20 years ago and being told that useful results from string theory were only a matter of time. The question is how useful?
I loved the PBS bit about the deal with gravity, that maybe its not a fundamental force but can be thought of as a form of entropy. As it seems so illusive in Quantum mechanics
I've been curious for a long time why String Theroy didn't go anywhere. This's a very informative video. Thank you, Sabine!
Wow, Sabine-- You came, not to praise string theory, but to bury it. And appropriately dressed for a funeral.
Thank you Sabine, very good summary. I read Lee Smolin's book "The trouble with physics" a very good read. He explained how human physicists are in the sense of falling into group think. Scientists are not as objective as they like to think they are! I also read that Roger Penrose described String Theory as "not a theory of physics but a theory of mathematics" So it has use as an elegant mathematical tool but that maybe its limit.
Very technical, but I stayed awake the whole time, though my brain was in a different universe 😃 Thank you for sharing this concept of string theory and it’s conflicting theories. Well, I’m glad you didn’t achieve tenure, so that I can learn something outside the field of phisics
This is a victory lap for Sabine. But face it - no one still cranking out string theory funding proposals was going to say it.
A serious dead end for lot of physicists.
Nothing is as hard to disprove is an interesting idea that brilliant people find plausible
Hard to disprove is the wrong term, since its never been proven.
I sure philosophers / sociologists of science will have interesting things to say about the string wars in due course.
It's not an "interesting idea", it's a complete theory, and it's likely the only possibility for quantum gravity.
Spot on, my friend. Spot on.
@@RockBrentwood I can't understand this comment. Oppenheim? Except being none at all? No quantum gravity? That's silly rhetoric.
I work on super symmetry at CERN. There are many ways to motivate it that are unrelated to strength theory
Hi Sabine, I love your stuff. I'm afraid you miss-labeled a photo of Mr Woit around 13:30...
Just a note, it should be "What ever happened" rather than "Whatever happened". The "ever" serves as an intensifier for the "what" in "what happened", where "whatever" is an unrelated word. Confusingly, there's also the similar-sounding phrase "whatever happens", which means "no matter what happens".
The Whatever Wars.
@@audiodead7302 I mean, "Whatever happened" is valid too, but it means something different. "Whatever happened to Dan, we must press on" = "No matter what happened, we must". If you're asking "What happened to X", it's unambiguously "What ever happened to X" and not "Whatever happened to X".
Mistakes happen. Context goes a long way to straighten them out.
The “whatever” is possible in an Anti-DeSitter space.
At least grammar makes sense.
Thanks Sabine, I couldn't agree more. It's why I left physics for a PhD in a different field that might, unexpectedly, get us closer to an understanding of everything
Don't leave us hanging. Which field did you choose? What about it do you think will help us understand everything?
@@Frostbiker Machine learning at a faculty with brain, behavior, and language researchers under one roof, two years ago
I’d suggest economics. Funding is the greatest limit on human understanding.
@@troglokev This isn't some use AI to accelerate science play, it really is about finding certain answers.
@@Frostbiker missed the second part of your question, but it boils down to: Thermodynamics Information theory Continuity is compression Automata Emergent behaviour But it takes too much articulation as to what the common and missing factor of understanding in all this.
Excellent summary, thanks!
My physics teacher in secondary always took the piss out of string theory. Said it can’t be a theory if it’s unfalsifiable because it requires higher dimensions we know no way to measure. I always argued with him to be a contrarian but I think he was probably right. It’s abstract maths twisted around as much as possible to fit what we see.