Doctor Asks Physics Questions (ft

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I meet with the amazing Dr Rohin Francis in London and did my best to answer his questions about physics.
The second part of this video is here: • Physicist Asks Unhelpf...
You can support us on Patreon: / sabine
0:00 Intro
0:51 Is dark matter just a fudge?
3:25 Is dark matter here?
4:44 Why do physicist constantly build bigger things?
7:29 Is physics done?
9:10 Why is quantizing gravity so hard?
11:02 How long until we see evidence for quantum gravity?
12:03 How do we know there's nothing smaller than quarks?
14:42 What's your favorite particle?
16:12 Can you magnet someone to death?
19:14 Why is life so close to absolute zero?
20:50 How do you think the universe will end?
22:30 How would you die when you go into a black hole?
24:58 Sponsor message
#physics #science #scicom

[@joshieecs]

I see. [writing notes] And Is this "dark matter" in the room with us right now, Sabine?

[@AdrianColley]

You say these neutrinos are all left-handed. Did you have a traumatic experience with a left-handed person when you were a small child, Sabine?

[@martir.7653]

Haha that's so clever

[@YounesLayachi]

Lolololol

[@MedlifeCrisis]

😂😂

[@Fitzliputzli23]

Haha, that's a good one! You made my day!

[@violetfactorial6806]

"Can you magnet someone to death?" "Yeah probably, but it's easier with an electric field."

[@orlock20]

If you can stick them in a microwave oven, electrocute them or get close to a magnetar.

[@ypey1]

This is usefull information

[@joemacleod-iredale2888]

Just bash them with a big magnet…

[@frauleinhohenzollern8442]

"It takes a lot of energy to pull these quarks apart because of the strong nuclear force, which is strong.... as the name suggests"

[@AP-nj1mr]

Arsenic is even easier!

[@MentalEdge]

The idea of experimenters going "I have this measurement, explain" to theorists is hilarious for some reason.

[@AdrianColley]

I always thought the Michelson-Morley experiment had that badass feel. "OK, so we experimentally proved that the speed of light is the same as measured on earth regardless of orbital dynamics. Go figure, eggheads!"

[@YounesLayachi]

Totally

[@kashu7691]

@@AdrianColley even funnier that we gave up and considered it a postulate instead

[@CausticLemons7]

It's like they showed up with a box of parts and told the physicists to put it together without instructions.

[@metinersinarcan92]

@@kashu7691 At the end of the day, you should accept some experiments as postulates. You cannot prove something from nothing.

[@LeoStaley]

This is the kind of Q&A I have wanted for a VERY long time, where experts in one field ask their own personal questions of experts in other fields, and ever since I have discovered both Rohin and Sabine you were both the specific experts I had been wishing for. I can't tell you how wonderful this is to me. I just wish this was a more common kind of educational video format. Another good one might be an engineer and an anthropologist, or a biologist and a climatologist.

[@ChristianHedman]

It's a fun and intersting way of understanding science and scientists. Hopefully one of the science youtubers take on this concept; I think it would be wildly successful.

[@merlepatterson]

Or maybe even a discussion between a high school drop-out and an acclaimed academic genius? What might be learned given this scenario?

[@williamverhoef4349]

@@merlepatterson Or an expert in any field with a non-expert in that field who nevertheless thinks the experts in that field are all wrong. That would be great fun.

[@The268170]

I'd like to see a philosophy guy vs a religious guy too ^.^

[@echelonrank3927]

or a climatologist and a brain scientist. what is corruption is it something inside my brain?

[@domainofscience]

This was very entertaining! Remind me never to get into an MRI machine when Rohin is about.

[@ricardodelzealandia6290]

Map idea for you Dominic - a map of physics theories. There's a lot of them out there and there's correlation in them.

[@rchdigital1295]

He is probably at his best in a cathlab!

[@CAThompson]

@@rchdigital1295 Having had a temporary pacemaker put in at a cath lab, I wouldn't want someone at their worst. 😬😆

[@Linshark]

Luckily you need super-strong magnetic fields to kill someone.

[@adeloulaikb]

P

[@justinahole336]

"...they are a little odd and a weakly interacting..." LOLOLOL!!! That is why I so enjoy Sabina! Awesome!

[@DrDeuteron]

but is she left-handed?

[@gumbilicious1]

Only when you reverse her charge and send her going backward in time

[@concinnity9676]

That was at 14:45, and it had self-effacing charm. Sabine is so smart she knows how to get us geeks to like her more.

[@seancidy6008]

@@concinnity9676 She calls out uber geeky scientists who want to build ever more massive colliders. They don't like her.

[@sicfxmusic]

She has lot of internet friends tho, about 350k 😁

[@aryanranka4765]

They said Avengers will be the biggest crossover

[@Mormielo]

They were lying.

[@Foolish188]

The Marvel-DC crossover was pretty big. But I haven't read it, think I heard that Superman can use Mjollnir.

[@AdrianColley]

In this crossover, they specifically aim for the head.

[@tangibleblockofwisdom6386]

SPEAK NOT OF LYCRA MEN IN THESE HALLOWED HALLS

[@mmmk6322]

Wah i didnt expect this collab! This is great!

[@stevenburdick424]

I believe in the Big Crunch.

[@StrongMed]

"Physicists don't just invent something to make their sums work out..." [Einstein inconspicuously kicks his cosmological constant under the sofa.] (In all seriousness though, enjoyed the video - thanks for sharing!)

[@mastershooter64]

String theorists working on M-theory: [Inconspiciously kicks their extra 7 dimensions under the sofa]

[@StrongMed]

​@@mastershooter64 So true! Lol.

[@MemphiStig]

she explained in a recent video that the cosmological constant is a legit and important part of the relativity equations. i was also under the impression it had been dismissed as a mistake, but i'm no physicist, and i have at best a partial understanding of what she's on about sometimes. here's the link, if you care to try to follow it. kzbin.info/www/bejne/mJ3CqHqIm8eWadk

[@StrongMed]

@@MemphiStig Thanks for the link, but I was referring to the fact that when Einstein originally introduced the idea, he had no explanation at all as to its physical nature (not that we really have a good explanation now). Einstein just threw the extra constant into the equations because it resulted in a static universe to which he had an unscientific, philosophical attachment.

[@MemphiStig]

@@StrongMed yes i know. i was too.

[@happyhome41]

This was a most wonderful opportunity to be a fly on the wall, and vicariously enjoyed the interaction of two highly intelligent, articulate, and accomplished people, from different domains.

[@epajarjestys9981]

It was a much better opportunity to be a human being, watching comfortably on the computer from home. Why would you want to be a fly? You would probably understand much less that way.

[@s.r.howell1297]

@@epajarjestys9981 They might have been talking about their favourite flavour of jam.

[@Hexanitrobenzene]

@@epajarjestys9981 "If I could be a fly on a wall" ... is just a saying for " (If) I had an opportunity to see something I can't get access to..." The person was basically admiring the capablity of the Internet to share high quality knowledge from primary sources.

[@epajarjestys9981]

@@Hexanitrobenzene But this makes no sense, because obviously we do have access to this conversation. No need to wish anything absurd for that.

[@SecularEvil]

"Vaccines won't make you ferromagnetic" "So you claim" *cut* lol!

[@oldvlognewtricks]

Arid as fuck 😍

[@Jake.The.Snake.]

17:03 🤣 that was a very clever joke

[@holcus1]

Ali G is back

[@johnbroussard9480]

I thought the Doctor's questions were surprisingly thoughtful and original. His MRI experiences, 3 vs 6 or 7 Tesla magnetic fields, were highly intriguing.

[@WestleySherman]

Peripheral nerve stimulation (PNS) seems to be due to the MRI magnetic fields changing in time, inducing electrical currents. And levitating frogs, or other small (diamagnetic) organisms, is possible in a magnetic field that is unchanging in time but that has a very strong spatial gradient, where the magnetic field goes from very weak to very strong over a very short distance. But it would be interesting to know whether an ultra-strong magnetic field that was unchanging in time and spatially uniform could still cause biological effects, for example, due to Lorentz forces on the ions. At the very least, moving perpendicular to the field lines might result in some heating.

[@georgelionon9050]

@@WestleySherman If you move in a static magnetic field, it's a dynamic one, from your point of view.

[@rh4009]

I expected Sabine to comment on how strong of a field is 7 Tesla in the grand scheme of things. Is this the order of magnitude where you expect chemical reactions would be affected?

[@georgelionon9050]

@@rh4009 No.

[@johnbroussard9480]

At what magnetic field strength would biochemical effects be noticeable? Perhaps there is no easy answer as the current field interaction with biological matter is not well known. Wouldn't be the first time new technology had deleterious effects on humans. ( Xrays, alpha radiation, microwave radars.) However I am no Luddite. MRI scanners are wonderful machines. Now that we are entering the age where they are used to connect exterior stimuli to subsequent localized brain activity, it would be handy to know what Tesla strength effects this brain activity as well. I'm sure many researchers have had similar thoughts.

[@KNemo1999]

"Physicists don't make up things to make their sums work out." Einstein's cosmological constant has left the chat.

[@tissuepaper9962]

*Max Planck quantizing energy as an absolute last resort to fix the ultraviolet catastrophe be like*

[@KNemo1999]

@@tissuepaper9962 :)

[@AdrianColley]

"... any more."

[@mjmulenga3]

Max Planck has left the chat.

[@tellmemoreplease9231]

Good Point, Well Said

[@DrDeuteron]

If dark matter is a fudge, we need to call it Dark Chocolate Matter (DCM).

[@thePronto]

Thanks, now I have to go buy a cake! Ideally a Schwartzvalder Kirche Kuche, if I can find one.

[@PMA65537]

@@thePronto church or cherry?

[@thePronto]

@@PMA65537 kirsche... lol

[@AdrianColley]

@@thePronto If you get a really big one, you can call it a Schwartzschild Kuche.

[@thePronto]

@@AdrianColley turns out there is such a thing, but I want to eat the cake, not have the cake eat me.

[@thefountainpendesk]

The collab no one asked for but we didn't know we needed

[@fudgesauce]

One answer I've heard to Rohin's question at 19:19 -- "why is life so close to absolute zero" -- is this: it is at the scale of cells around room temperature where various forces have comparable absolute energies. Eg, thermal energy, chemical bonds, electrostatic forces, charge transfer are similar. In different regimes one force or another dominates and the resulting systems would be too simple to host the complexity required for life to exist. "Cell Biology by the Numbers" by Ron Milo and Rob Phillips. There is a diagram on p. 159 which shows how these various force scale converge to the same neighborhood where life as we know it happens.

[@PMA65537]

After getting my physics & theoretical physics BSc in the last century I applied for some medical physics roles (that in fact I never got and did something else). At one hospital for interview I was told you must never tell any doctors anything wrong (simplified is ok but not wrong) because they will remember it for life.

[@hobermaas4166]

A more accurate quote would be : prepare yourself to reiterate the same thing ad nauseam because doctors only remember what's clinically useful. You'd think most of us have eidetic memory, but that would be wrong ; we preserve the clinically useful information, everything else goes into the working memory churner.

[@pshehan1]

When I was a Post Doc from Australia in Syracuse NY, my friend who was a scientist like me but was in charge of an MRI scanner told me that when lecturing to medical students he would put a rubber tube in a lab coat pocket to mimic a stethoscope so they would pay attention. "Doctors know squat" he said. Not entirely fair as i have helped supervise medical doctors doing masters or PhD's but they take some time to adjust to the fact that the answers are not in the text books. Research is about figuring out what the question should be, and there is no guarantee about the answer, or whether you can find one. One said to me, "Give me a tough night in casualty any day." They work out in the end.

[@georgesheffield1580]

I have found this out trying to teach to medical personnel , the issue of continous learning and refining knowledge .

[@thePronto]

"Is dark matter just a fudge." He wanted to say: "Are cosmologists completely clueless about almost everything in the cosmos, and wouldn't they have been happier (and richer) by becoming cardiologists?" EDIT for all those triggered by this comment: Please read this in Rohin's voice per 'Medlife Crisis'

[@manco828]

Cardiologists hate runners.

[@Bharat-qe8pp]

Don't go to doctor if you ever fell ill . Don't hate any occupation or job. Doctors are like second god

[@clairegetscrafty]

That's such an accurately Rohin-esque reply!! 😂😂

[@CAThompson]

@@Bharat-qe8pp That's stupid - I am not dead because of medical doctors. I would be if I followed your advice.

[@brawnstein]

@gustav champoski That is the thing, we do know a lot about dark matter given the fact that it does not interact with light and we have a lot of evidence for it.

[@dominic.h.3363]

"Why is life so close to absolute zero?" - This is what I've been wondering for many years, but never found someone explaining it!

[@ThatCrazyKid0007]

Basically thermodynamics and entropy.

[@smallsim2663]

Live is "cool" 😄

[@dominic.h.3363]

@@ThatCrazyKid0007 Many of the explanations I've gotten are just rephrasing the question and forget to put a question mark after their own "explanation". "Because a lot of the chemistry is not happening at higher temperatures." The question still stands. Why?

[@alwaysdisputin9930]

@@dominic.h.3363 isn't it just that above 100 deg C particles become so energetic that it rips apart all molecules?

[@CAThompson]

@@alwaysdisputin9930 Not at all. Boiling water is 100 degrees C, so the molecules just seperate into steam.

[@SeanKennardRN]

I would gladly spend the rest of my life listening to (and learning from) Sabine. What a time to be alive✨

[@patrickfitzgerald2861]

". . . if you lack imagination, you make it bigger. . ." Sledgehammer Sabine hits the nail on the head yet again! 🥰

[@AdrianColley]

I like how you imaginatively made your hammer metaphor bigger.

[@patrickfitzgerald2861]

@@AdrianColley Peter Gabriel helped me out with this one. 🔨 😎

[@DrDeuteron]

Nice, but I would prefer a Chubbyemu collab: Physicist tried to unify gravity and quantum mechanics by adding extra dimensions: _This is what happened next_

[@sermon1984]

Me too

[@dryan89]

Sabine, I love your clear no nonsense approach to physics communication, very refreshing. Thank you for the quality content.

[@triberium_]

I love it, two professionals asking each other about their profession! Shows you that someone educated on one subject could not be as educated in another.

[@LelandReview]

You know how true that is. My youngest brother nearly died from a infected wisdom tooth. And the issue came because he went to the hospital to get his face swelling diagnosed. It looked like he had bad case of the mumps. But Dr's at the hospital knew next to nothing about teeth. After a year bedridden in hospital on IV i convinced him to go see a expert dentist. They found the infected tooth under the gum line. Pulled it and he was back to normal in couple days. I asked my dentist how could this happen. He said Dentists and Dr's rarely learn about each others field of study. We need more polymaths.

[@zoltanposfai3451]

"Can you magnet someone to death?" "Sure thing! Just find a large enough magnet and drop it on someone." Neutrinos are my favourite particles too. (Not only because I had involvement in related research.) They have still so many mysteries that will influence our entire view on the Universe (and any sort of all-in model). We may have answers lurking there for black matter and quantum gravity.

[@fudgesauce]

I love that this prestigious institution, with its walls of books to give weight to the claim, has a broken shelf. It appears repeatedly, but to pick one moment, at 19:23 it is the bookshelf right in front of Rohin.

[@ypey1]

Too much dark matter

[@peterfireflylund]

There are little pegs that support the shelves and there holes in the vertical sides of the book cases. I think somebody put two pegs in the wrong holes under the left side of that particular shelf.

[@TiagoMorbusSa]

Such a fantastic collaboration, thank you!!! 👏👏👏

[@hbarringer254]

Very insightful, thank you Sabina and Rohan. Would love to hear some more questions answered! Fantastic

[@baterickpatman]

Thank you guys so much for doing these two videos, I was already big fans of each of you individually, what a pleasant surprise when I saw this pop up :)

[@avermaak12]

Just love these videos! Sabine is so awesome and a true bare knuckle scientist, speaking frankly and making the subject so accessible. Love these videos

[@echelonrank3927]

shes smokin'

[@hominessapientes]

Thanks a lot for your videos. These two are no exception - both great videos, and also glad to have found Rohin's channel through you.

[@ODSD_EXCITEMENT]

Very much appreciate the calmness and freeing disposition you have and project regarding such specialized and complex subjects. Thanks for sharing. I'm learning so much about topics I love and want to know more about.

[@9snaga]

Fantastic collaboration. Both channels I have followed for a while.

[@waynesaban2607]

I REALLY enjoyed this, as the Physician asked some questions that I have often wondered about. I was also somewhat pleased that I anticipated some of Sabine’s answers, largely because I have watched so many of her videos. Lol. Please do more of these.

[@bumblebaa2327]

Hossenfeld's explanations are wonderful! Also her ability to skip over things and keep the main thread of thought going. "Then what happens next, because of quantum-things, is …"

[@cryptocrush-823]

This is a very cool concept! I love to hear 2 very different ppl, from 2 very different professions asking each other questions about their professions. Thanks for sharing!

[@OrafuDa]

Very very good! Dr. Francis is asking very interesting questions, and Dr. Hossenfelder is very good at answering them! This is a blast, and very informative! Thank you!

[@brianbutton6346]

Larry Niven made a short story relating to the last question on this interview, Neutron Star. It was a pretty awesome treatment about the challenge of dealing with a strong gravity differential.

[@CAAnmoldeepsingh]

You've got to be kidding me, my fav med youtuber and physics youtuber coming together.....lovin it.....💓

[@rudetuesday]

I really enjoyed the variety and level of questions and answers in the pair of videos, and will watch at least a couple more times. Thanks for making them.

[@ShamanicKnight]

Wow! This was great... Really loved listening to this discussion. Thoughtful questions - and, as expected from the great Sabine, great answers... Brilliant!

[@modolief]

Thanks for the collaborative video, this seems like a great concept.

[@ruinenlust_]

the dog in your yt banner is a very good boy

[@mynvs-]

​@@ruinenlust_ you have an incredible good boy detector

[@dugger0]

You are my favorite physicist. Your sense of humor cracks me up every time. I hope my daughter can grow up to be like you.

[@IwoIwanov]

Fantastic format. Superb conversation. Keep it up.

[@alexz7914]

I am so happy to discover this channel and this turned up in my recommendations. Such an interesting and educative discussion. Thank you.

[@piernikowyloodek]

OMG! What an ICONIC DUO!

[@WackyAmoebatrons]

"We're gonna need a bigger collider" -- Roy Scheider in "Jaws", sort of :-)

[@10-AMPM-01]

19:17 I'm glad I'm not the only one that has noticed the strange warm tingle when you're in a high power MRI. It makes me very uncomfortable, ionizing my liquids like that.

[@rayoflight62]

Truly exceptional. Thanks to both of you!

[@etmax1]

Red blood cells can be either diamagnetic or paramagnetic depending on whether the haemoglobin is bound to CO2 or O2. These 2 are amongst my most revered specialists in their field, it's good to see them collaborating.

[@michaeldalton1874]

I LOVE it when KZbinrs colab! SOOO FUN!!! 😁

[@mitesh8utube]

This is the first collab I watched on YT, ever. I ignore collab videos as a general principle. But these two are most no-nonsense youtubers I know.

[@PlanckRelic]

Your content is always interesting, but the flow and tenor of this conversational style makes it the best video of yours I've seen so far.

[@isabelab6851]

Fabulous video,! Thank you!

[@nestorlovesguitar]

"Next time a patient asks me something I don't know the answer to I'll just answer 'because of quantum things'" LOL

[@user-wu8yq1rb9t]

Wow one day and two videos, and this one is different. *Great*

[@peterb9481]

I am a fan of both of you and both channels. Was great to see you teaming up, interesting to see more the lay person asking questions and the expert answers.

[@edmundkempersdartboard173]

I love the dismissive chuckle when she says "string theorists." 😀

[@HkFinn83]

Inferiority complex.

[@catharsis21]

Program swaps are IN! Good job!

[@dangaines405]

Great format for the interview. And great questions! Thanks.

[@cordatusscire344]

Fantastic presentation, and great conversation!

[@almcdonald8676]

Hahaha of all the crazy team ups I didn’t expect!

[@kingfisher1638]

wow great crossover

[@rudolfsykora3505]

This is so cool, watching bouth of you independently and now you interview each other, thank you for being here with us

[@jonathanjollimore4794]

Thank you for all the help still A LOT unanswered questions not done yet

[@kendoolin]

The standard model could be humanity's greatest achievement. I would call it the f**king awesome model but I love how physicists simply call it the standard model.

[@davidmcc8727]

But the standard model contains parameters which do not arise naturally from the model

[@juanausensi499]

@@davidmcc8727 True, but still it is our greatest achievement for now.

[@scptime1188]

@@juanausensi499 Second greatest achievement would either be general relativity or the unification of special relativity and quantum physics.

[@silentwilly2983]

Rohin's question about absolute zero makes me feel good, it's clearly not my fault that people act so cold towards me...😂😂😂

[@lucasmano8187]

Loved this interview!

[@vinicius.schmidt]

Both of my favorite youtubers! Thanks for this!

[@m1lkweed]

"Maternity Universe" The captions feel autogenerated but youtube disagrees

[@janerussell3472]

What Sabine didn't say: "Banging particles together at higher and higher energies, until the very fabric of space-time rips, is a game for scientists who never grew up."

[@stevearmstrong7023]

Great video Sabine - love this concept - you should do this more.

[@jamielondon6436]

This was super helpful, because you managed to keep the answers/explanations do a level that he - and thus I - could understand! Please, feel free to do more of these. :-)

[@clayz1]

I’m so glad that that other people have the same questions about dark matter. Especially from educated people (I’m 1970’s high school and some classes). I always think we are in a thought cul-de-sac. I do not, however, think that I’m more than a basic idiot compared to the educated. Sabine is a whole lot of learning fun.

[@mbrackeva]

If you acknowledge your limits and care to listen to people who "know better" then you're far from being an idiot.

[@xCorvus7x]

17:14 In response to Rohin's interruption you look shocked, as if you weren't sure whether he's joking (which, I assume, the two of you have resolved in the cut at that point).

[@thorr18BEM]

He's always joking.

[@KeithCooper-Albuquerque]

Having two of my favorite KZbinrs in one place is awesome! Thanks so much, Sabine!

[@davicruzpestana7329]

Wow, really loved this video format. Sabine just has such an beatifull way of explaining. Really loved the question at 12:03

[@pridefulobserver3807]

"The perfect crossover does not ex..."

[@CAThompson]

* Batman slaps Robin *

[@BB-cf9gx]

Sabine: ie dark matter. "If it exits..." Well yes that remains the unanswered question.

[@TheSpoonwood]

loved this! thank you

[@MeppyMan]

I didn’t know I need this crossover until today. Thank you both!

[@KKzkas]

Naive question: Why ugly shoes? Is it some kind of sublimation of too high IQs?

[@clairegetscrafty]

Hahaha! No, if lack of fashion sense was a sign of intelligence I'd be a proper genius!! Given Dr. Francis's hair (possibly messy from a helmet) with those particular boots, my assumption is that he rode his motorbike in.

[@CAThompson]

I used to wear weird sneakers a lot. Gurl is representing weirdos everywhere.

[@eljcd]

Somebody doesn't suffer from bunions here...

[@paulgoogol2652]

High heels are ugly. She wears normal shoes.

[@CAThompson]

@@paulgoogol2652 High heels look amazing if they are good shoes but they're hard to walk in.

[@ThePicManiac]

Great questions from dr. Rohin, thank you

[@F1.4the-moment]

Just come from his video. You’re both awesome, and I’m awestruck by this meeting of two great educators. 🤩

[@kjrunia]

Loved this, and not just because you're explaining physics as well as ever, but you're also demonstrating how to communicate what is deep and technical stuff. I also appreciate immensely how you're avoiding all the flashy metaphors just to sound cool but actually point out the areas where physicsts tend to hype where no hype is warranted other than just to come off as being the cool mad genius. You're even pointing out where other physicists would disagree with your viewpoints. All in all, thank you, Dr Hossenfelder.

[@carstenbjrneboe5774]

Brilliant, really enjoyed this 😊

[@mickruban3567]

Really enjoyed both videos. Thanks.

[@erdnaerramal]

Really like that concept. thanks !

[@johnneat3381]

this was amazing!!! i had an awesome time listening to u both

[@blair2798]

Fascinating interchange. Very enjoyable and understandable.

[@kenczepelka6314]

Sabine is my favorite popular scientist. Videos like this just add to the fun. The questions in this video were thoughtfully asked and thoughtfully answered. Great to see this kind of interaction. Thanks Sabine for adding so much to this world!

[@samheasmanwhite]

This was really cool! There were actually some pretty good questions and even for the layman questions your answers really led towards the most interesting parts of the science. I hope you do some more of these, but definitely go with your gut on whether it will lead to something interesting.

[@MCsCreations]

Pretty interesting conversation indeed! 😃 Thanks a lot! Both of you! Stay safe there with your families! 🖖😊

[@GigiofGigi]

Thank you Sabine! Very cool different style of video

[@Zhoomz]

Ooh, I've actually been wanting to see a Q&A actually! Awesome surprise to see

[@clacclackerson3678]

Two of my absolute faves in one video, thanks!

[@woufff_]

Very interesting and very well answered, thanks Sabine

[@BrianPseivaD]

Such an amazing scientific mind, keep making videos they are amazing!

[@malinkifox2011]

Glad I discovered your channel. I’ve been watching everything on Sean Carroll and this is an awesome addition to new views from another expert!

[@Ryu-oj9wz]

Amazing , a talk between my favourite intellects , can't imagine anything better ✨

[@PaulJonesy]

This was great, thank you.

[@stephenpuryear]

It wasn't very long ago that no one understood what function the heart performed- Harveys approach to an answer was actually brilliant. Great channel!