The background behind you suggests you're taking the social distancing very seriously.

One of my biggest joys while being quarantined here in a hot zone part of California is watching Professor Caroll's "The Biggest Ideas in the Universe". Thank you for sharing your knowledge with the rest of us.

Oh my god that expression at <a href="#" class="seekto" data-time="1580">26:20</a> when Sean calls Emmy Noether “Emily” is just priceless :’) Thanks for not cutting (or more likely failing to cut) that out.

OH MY GOD. I failed out of calculus three times in college. I only stopped because it was ruining my GPA. I wanted to be a physisist since I was 9 years old and tried and tried, but couldn't grok the maths! (I became a computer scientist instead LOL} The theory absorbs like a sponge but the nuts and bolts, I eventually accepted, were simply beyond me. Apparently my professors just were terrible! This video, and the barebones mathmatical theory involved, was an Eureka! moment for me, and youir explaination was just a tangent! Thank you, Sean Carroll! I feel foolish for not seeing the relationships I had at hand, and also a burning rsentment of what counts as an educational system in the United States for failing to actually educate me as me as a young, enthusiastic, student.

A positive effect of quarantine is that we now have a greater number of scientists doing their own podcasts and getting knowledge of complex topics into the general public.

I’d like to think the Many Worlds theory includes a universe in which I understand all this.

"I will not be naming everyone, just the ones with really funny usernames."

ENERGY IS REAL. YOU'RE RIGHT, SEAN. THERE IS NO CALORIC.❤

You are such a great Teacher! I wish you could also do more advanced, full-fledged physics courses in this exact format, with mathematics and all that🙄

Suggestion: maybe a quiz at the end to see and apply what we've learned to help store it??? Like a challenge for us just learning. Thanks.

First question almost made me pass out I was laughing so hard. I would watch and hour of Sean reading usernames with a straight face. PRICELESSLY FUNNY!!

LOL at the cat chaos causing timeline jumps. Only Sean's cats could do this :)

I don't believe I am watching this. Finishing my second glass of wine and laughing hysterically. Fifty years since I graduated from college. The best I got in calculus was Cs and I pretty much forgot everything. Pretty uninspirational teacher. Took Khan Academy High School Calculus BC last year for awhile, so the waters are not so muddy. All that said, I am sort of following and sort of comprehending. Thank you. I bought your book, Something Deeply Hidden, and read the first few pages and I pulled out Laurence Krauss"s book, Fear of Physics and reread a bit today. He also mentions the cow/sphere analogy. Thanks for this.

I've just finished Feynman's six 1964 Messenger Lectures at Cornell, so this series is a great way to reinforce these ideas.

I absolutely love these. Thanks, prof. Keep 'em coming!

I’m loving these. Please keep it up. Thank you.

So happy your subscriber base is growing. Not a measure of how brilliant you are!

Hello from Italy, professor, love what you’re doing with this series of videos!

I’ve been a Patreon supporter of Mindscape since the beginning and a big fan of your work in general. You bet I’m going watch this series!

You're an awesome company in days like these. Thank you so much for sharing your knowledge to a wider audience! Regards from Louise, Sweden.

Thank you so much Sean for the time you put for explanation these fundamental concepts. Awesome timing as well while we are mostly at home.

Thanks for this. Videos and Q&A a great combo

Wow what a series this is turning out to be! Its good to see you've already become very accustomed to presenting your doodles on the ipad, you seemed to be having a lot of fun with it. The whole presentation flowed super smoothly, well done and thank you so much!! I didn't know you were doing Q&A, hopefully I can offer you a few questions relevant to your upcoming topics. Thanks once again for such an amazing presentation, we're all truly humbled by your efforts as one of the worlds leading communicators of science.

carroll is arguably the best guide and explainer, when it comes to the mind-boggling , mind-stretching, contents of today's physics. He explains and even entertains, without oversimplifying and dumbing down the subject.

I'm so glad that I've discovered this series, thank you! :)

Excellent as usual. As much as I enjoyed the initial talk on conservation of P. This Q&A video was even MORE enjoyable. You do have a great gift for teaching. Every time you digress or expand on an explanation of some kind, its like you read my mind and answered the questions I was thinking about!!!!! I have read Feynmans Six easy and not so easy pieces (also read his biographies, etc). You absolutely deserve to be sitting at the great mans desk. Thank you for this video diversion in these crazy times.

Thank you so much, from Italy on lockdown I appreciate the chance to learn such interesting things. I got to understand and love physics from you.

Your stuff is amazing dude i love listening and getting my mind melted 😂🙏 keep it up!

Your sighing at the wave function really shows how much you are willing to respect your other colleagues in the field. Its almost like you are doing your best to acknowledge their POV although you've done so much to educate so many about a much more expansive POV that identifies the wave function as the fundamental underlying reality. Its kind of nice, it demonstrates the type of humanity you have.

This is wonderful, I'm watching it again.

First, I was being lazy to tap in the video after watching this time line, but after tapping on it, It was like.... Why this video ended! Sir! I learnt a lot today and I am Very Very much Happy that I watched the video which clears all the basic doubts! Thanks! ♥️🙏Love from India!

I've followed the podcast since the beginning. I'm not smart enough to understand 100% of the stuff that comes out of your mouth but I'm still enamoured by the physics. You make me second guess the thoughts in my head that tell me my lack of math and science means I shouldn't or can't learn more. You broaden my understanding, thank you.

To a motivated learner , these videoes are of great help 👏

I like how you answered the Galileo, Newton, Ibn Sina question. Specifically the history Galileo experienced in Italy 🇮🇹! Great work!

Great stuff. just what I need while at home..

Thanks for this series. I am enjoying it a lot !

Keep em coming. Love your lectures

"Is the Universe a closed system? All the evidence we have says yes." Roger Penrose: "Hold my crumpet."

Great idea ti share with us your knowledge and excelent teaching abilities during this selfquaranteen time. I enjoy it very much

Excellent. Thank you.

First? maybe. keep up the good work, i really enjoy this

Fantastic , Thanks Sean

Good to see you in a pod cast Sean

OMG! liked before watching.

Thanks for answering my question!

Thank you so much Sean!

Keep it up! This is great.

I just watched your first video, and loved listening to your understanding and explanations. you did make one comment in the q&a where you said that the photons energy will not be conserved as it is stretched through the expansion of the universe. You said that the energy goes down as the wavelength stretches, which is true, except that the actual energy in the photon does not change. if the energy in the photon changed the photon could not be moving at the speed of light. As it is moving at the speed of light the photon experiences no time. From the point that it left Galaxy X 13 billion years ago the photon has experienced no time, and no change, until it reaches our detectors here on Earth. But as we are moving away from it now at near the speed of light, because of the expansion of space, the energy seems to be lower as it is red shifted, but it is only our relative movement that makes that light seemed lower energy. If we were moving towards that same light source, it would seem much higher energy to our precepton. I don't know enough about this to know that I'm right, I am assuming that I have to be wrong at how I perceive this, otherwise everyone else is looking at this the wrong way. Thank you thank you thank you again for putting the time in to these lectures. I have watched many of them and decided I needed to start at the beginning if I really want to understand these big ideas.

This is gold. Needs more subs!

Good morning Professor Carroll, Thank you so much for publishing such amazing content, in time like these it's great to see physics being divulged in such a simple cohesive and yet exciting way! Let me just begin by saying that I am a huge fan of yours. From your books to your podcasts and talks I have been following your work for quite some time now. I am currently trying to contact you because I just ended my BS Eng from case western reserve university in Engineering Physics and I have to say I am a bit lost on what path I should take next. I have a deep passion for physics, more in particular I like to question reality. A question I would like to answer is whether or not there is a unit of space time and if the Planck length truly is the ultimate unit of space time. Do you think that philosophy of physics might be a good path to answer such questions? Or do you think theoretical physics would be more appropriate? I know experimentally we don’t have a way to currently prove this, as we would need a particle accelerator immensely large to try and study the physics at such scales. I hope to hear from you soon Professor, Best wishes, and I look forward to more of your content in the Biggest Ideas in the Universe!

great !!!! thanks Sean!!!!!

Thanks Sean !

🙈🙉 thank you for this free education, The intellects are the true rock stars!

Enjoyed it

please continue this style vid

Very slick!

Learning much stuff....Thank you....

wow ! thank you very much !

You're a lovely person!

Freelanceteach vibes. Love it

Hi Prof Carroll, I just wondered if you have also been watching Brian Greene's "Your Daily Equation" ? I merely ask as a fan of both you and Prof. Greene. Thanks for this great new series BTW.

What the heck. Thanks Sir. Great, absolutely great

Great!

I hope you do an episode on mass, in particular the origin of mass as arising from the containment of massless particles (see PBS Spacetime “The True Nature of Matter and Mass”). I’d like to see this analogy extended into curved spacetimes so we can see how such a construction of massless particles experiences gravity and “feels heavy,” and if possible, how it could create curved spacetime/gravity.

the barion thing reminds me of cellular automata, where you have to input 1 cell for the system to start

I'm glad you talked about Baryogenesis and some less common conservation concepts, I honestly thought that you would skip it (like most physics explanation videos do). I'd rather you risk losing some of the more new people than just assuming that your whole audience can't understand. I like the concept of hanging some slightly difficult concepts out there in the hopes that it will inspire people to look deeper and understand those concept.

I love your cat anecdotes.

I don't know what it is, but I get way less out of these videos than I do from Sean explaining things, or discussing them, with another person present.

Thank you Prof. Carroll! This series are much appreciated for people like me that don't have the means to go to a university and learn from the best. I have a question. What about Hawking radiation, wouldn't that violate conservation of energy in some way?

thank you for this, einstein was before media, hawking couldnt talk, the world really needs to hear whats going on inside your brain, this mite be the most important thing on the internet

A question on the conservation of momentum: Do two particles exist in the same reference frame at the same time - whatever "same time" can mean? ie, does a particle continue at a constant velocity because inertial frames are distinct and an interaction is required to destroy a particle in one frame and create some in other frames?

I have heard your interviews in closer truth, as an athiest i would love to hear your videos and agree with the concepts

Good morning! If energy decays due to expansion, is there a relationship b/w dark energy & the vacuum energy?

I prefer this

Does anybody know if Sean Carroll ever does public speeches with meet and greets? That would be the thrill of a lifetime! I will always refer to the wide eye slight lift of the forehead stripped of facial twitches blank canvas with the glistening twinkle of humor in the eye as the Sean Carol effect, I’ve tried so hard to do it. One day I’ll get it down

<a href="#" class="seekto" data-time="2120">35:20</a> Would it be possible to have the decrease in photon energy and increase in vacuum energy to cancel each other out and keep the energy conserved?

<a href="#" class="seekto" data-time="2111">35:11</a> This is such a good explanation. Thanks for this. So this is also an explanation of not only e=mc2 but E = h · c / λ the difference always made me scratch my head because photons don't have mass from what little I understand and therefore could never really grasp how e=mc2 could be applied to them. So this energy then is turned into in some subtle way "vacuum energy" as you say - how is this explained in quantum field theory? Vacuum energy is just the neutral state of some discrete space/time field and somehow photons by losing all their energy or more accurately -> frequency & they become "flat" and disperse throughout the entire known universe all at once contributing to a greater sum of vacuum energy? lol. I think I'm stretching my brain too far but I greatly appreciate the videos, I'm really trying to educate myself recently - I have a long way to go!! (at least 23 episode :P )

I think a lot of the misconceptions in theoretical physics and cosmic philosophy are a result of us trying to use digital math to quantify an analog cosmos. Every quantum interaction is just fields interacting, and they don't have numbers associated with them. What is required is a fundamental change in how we view math. Numbers and equations are not the path to precision. We need interferometric waveform math, and I think the path to that is quantum computing. We have to design a system we can't possibly understand (even the engineers and physicists) It's like trying to conceptualize a fourth special dimension. We can't possibly fathom a fourth axis at 90° simultaneously to all of the 3 dimensions we experience.

Around the 20 minute mark, he discusses whether or not Galileo might have known about Ibn Sina or at least that Ibn Sina said that without effects like those from air resistance, an object would continue moving. I learned that Galileo used ramps so that he could more accurately time rolling balls by slowing them down. I now wonder if he also knew that he was minimizing the effect of air resistance. If he did, that might indicate at least knowing what Ibn Sina thought. I also wonder if Galileo had any guesses about if and how air resistance varies with speed.

THX

Question about black holes If from our perspective anything aproaching the event horizon of a BH slows down in time how can we see a BH grow. And how can we see two BHs merge. The only thing we "should" see is seeing those object freeze in time as they aproach the event horizon.

I wish I had found this series in time to ask about the relationship of kinetic energy (1/2mv^2) and E=mc^2. Except for the “1/2” term the two fórmulas are identical. Since light is a velocity and since it’s the maximum velocity, is E=mc^2 not related to the kinetic energy of a mass moving at c? Years after my two basic college physics electives, I thought I had some breakthrough understanding the intuitiveness of E=mc^2 when I first realized the similarity of the two formulas. But, I had forgotten the 1/2 term. Sadly, I realized after college so I couldn’t just ask my teachers in class the next day.

<a href="#" class="seekto" data-time="1890">31:30</a> RE: the discussion of photons losing energy as space expands... Is it possible that the energy lost by the photon is somehow transferred to space itself (and this conserved)? If so, could this process be at least a contributor to the non-zero vacuum energy? Edit: “thus conserved” not “this conserved”

T.O.E thesis: The collapsed wave of probability functioning similarly at unsame scales has a different appearance. Our sensory set reaches limitation of expected capacity at a different perceptual domains. In the same~ way, a planar observer of offset signwaves will see intersection at alternate opposite inflection points; where to a third-dimentional viewer, intersection within the same offset spiral-form waves never appears...

Could you talk a bit more about: If energy in an expanding universe is NOT conserved how (does it work) / why is the cosmological constant still fixed per cm of space and remains so, even as the universe expands? - Is the conserved / not conserved energy in the expanding universe related to the many worlds interpretation? Something like: the total amount of energy remains constant just not in our particular universe? Kind Regards and thank you so much for doing this. Henry B. - Stockholm, Sweden.

Take two rocks separated by some distance at time t=0. The universe expands until time t'=1, and now the distance between them is greater. The gravitational potential energy between those rocks should be greater now due to the increased separation. Shouldn't the same apply to galaxies? What am I missing?

A conservation of the one (energy) but not the other (mass) would violate the energy-mass equivalence. In fact a hot cup of coffee has more mass than a cold cup of coffee, even though the total mass of any particle is equal in both cases. "Mass" is not bound to the particles alone, but to the closed system "cup of coffee". And for closed systems the conservation of mass is still valid.

Good ass episode!

i think I need to watch this vid at least 3 times to get the flow of the lecture...

If you spaced heavy objects throughout the known universe would it bend the universe enough to win? I guess I'm asking is the constant dependent on the amount of stuff?

We know as a fact that the universe is expanding , which affects the space . And if space time is one thing in itself it should be affecting time too, right ? If that is true how does that happen ? And can we perceive this effect here on Earth ?

Nice

<a href="#" class="seekto" data-time="600">10:00</a> the statement at bottom is correct , but above he says the momentum is accumulated as it travels at constant speed ie the longer it travels for the more kinetic energy. I’m pretty sure this is wrong. Or am I wrong ?

Hi Sean!

Does particle physics distinguish between a closed system and an isolated system?

I've always struggled wiht the concept of expanding space. I know how to say the words but I don't understand the concept at all. How would we know space is expanding? Any physical ruler would exist within space and would expand along with the space. Does "speed" have meaning in expanding space? What about "distance"? It's so easy to say "expanding space" but I find it almost entirely unimaginable. Can anyone point me to somehwere helpful?

I enjoyed this video. I do have a question though..... what?

always wondered if it wouldn't save a lot of confusion among beginning physics students to write Einstein's infamy as dE/dm = c^2. Makes it rather obvious that the gain in mass in fission equates to excess energy which must manifest elsewhere in the system

Where could we find an antiparticle for every particle in our universe? Just considering that time were going both directions simultaneously, every neutron in our universe's time direction would be its corresponding antineutron in the reverse time direction. Every proton, its antiproton. And so on. Total baryonic number in both time directions: 0. Total leptonic number in both time directions: 0. A nice symmetry, two universes in one (the antiuniverse would however decrease entropy in its own time direction.... but "past" the big bang instant, and I mean "past in the reverse time direction," it would increase entropy as it goes longer and longer past that instant, whereas it would be our universe's particles that would decrease entropy before the big bang in our time direction. Not sure if this all makes sense. . . . Could time really be both directions at once? Semantics are not really helping in such a situation, "at once" meaning "at every one instant" in this case.

at <a href="#" class="seekto" data-time="498">8:18</a> - <a href="#" class="seekto" data-time="529">8:49</a> - perfect place to mention that Work = mad = force * distance?